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B Szafrańska

Publications and source records attributed to B Szafrańska.

11 recordsLinked to original sources

Ferroelectric ordering in imidazolium perchlorate.

Imidazolium perchlorate has been synthesized and studied over a wide range of temperatures by differential scanning calorimetry, x-ray diffraction, proton magnetic resonance, optical observation, and dielectric spectroscopy. Polymorphic solid-solid phase transitions have been disclosed at 487, 373, and 247 K. The crystal structure at 298 K has been determined as trigonal, space group R3m, Z=1 with a=5.484(1) A and alpha=95.18(2) degrees. The imidazolium cations are strongly disordered, while the perchlorate ions are well ordered. At 385 K the crystal structure remains trigonal, space group R3m, a=5.554(1) A and alpha=95.30(2) degrees . Both ionic sublattices are orientationally disordered. Temperature evolution of the molecular dynamics of the imidazolium cation has been characterized. In spite of a high cationic disorder, dielectric measurements have revealed the polar properties of the crystal. It appears to be a new ferroelectric compound with the Curie point at 373 K. The spontaneous polarization originates predominantly from the behavior of slightly distorted perchlorate anion.

Journal Article↗

Length polymorphism of PCR-amplified genomic fragments of the Pregnancy-Associated Glycoprotein (PAG) gene family in the pig and some other domestic and wild mammals.

Porcine pregnancy-associated glycoprotein genes (pPAG) are known as a multigene family, in which five members have been cloned and sequences of their cDNAs identified. Porcine PAG1 and pPAG3 genes, belonging to the pPAG1-like subfamily, both encode enzymatically inactive precursors. In contrast, cDNAs of pPAG2, pPAG4 and pPAG6 represent the pPAG2-like gene subfamily, encoding enzymatically active precursors. The objective of this study was to investigate the polymorphism of both pPAG-like gene subfamilies in the pig in comparison to other domestic species, including cattle, sheep and goat (Artiodactyla), their wild relatives (red deer and wild pig) and horse (Perissodactyla). This is the first paper indicating the polymorphism of the pPAG gene family, examined by lengths of amplified genomic fragments (PCR). Obtained PCR products were analysed in relation to five characterised cDNAs of pPAGs (pPAG1-like and/or pPAG2-like subfamilies) and according to one recognised structural exon-intron organisation of the pPAG2 gene, among at least eight pPAG2-like genes expected in the porcine genome. The highest polymorphism frequency of both pPAG1- and pPAG2-like gene subfamilies was found in the second region, exons 5 and 6 (with intron E). The length of PCR-amplified genomic fragments was approximately: 1043, 700, 600 and 193 bp. A high polymorphism frequency was found in the 3'-terminal fragment, corresponding to exons 7-9 (with introns G and H), more frequent the pPAG2-like gene subfamily. The length of PCR-amplified genomic fragments was approximately: 733, 650 and 356 bp. In contrast, PAG polymorphism was not detected in another region, encompassing exons 2-4 (with introns B and C). The length of PCR-amplified genomic fragments was approximately 279 bp in all examined genomes. In conclusion, amplification of various regions of the PAG gene family presents a relatively inexpensive PCR method of animal pre-selection with different genotypes. Such a pre-selection of animals is helpful for further gene number inquiry of the PAG gene family in each animal, then in related generations. The obtained results provide a useful background for a genetic marker preparation (by Southern analysis of the PAG family) that will presumably enable an economical early selection of young animals for effective reproduction.

Journal Article↗

[Risk factors for atherosclerosis in offspring of parents with primary hypertriglyceridemia].

High triglycerides and low fibrinolysis activity are considered as a significant predictors for atherosclerosis. The aim of our study was: 1-to compare these risk factors levels in children with positive family history of hypertriglyceridemia (HTG) with children from healthy families and 2-to assess the association between triglyceride and fibrinolysis activity in offspring (y) and parental risk factors (xl ... xn) for atherosclerosis. The study population consisted of: I Group 15 children 7-12 years old and their parents from HTG families and II Group 26 control children 5-12 years old from healthy families. Triglyceride (TG), total cholesterol, cholesterol esters, LDL-Ch, HDL-Ch, HDL2Ch, apolipoprotein AI and BII, fibrinogen plasma level were determined. Plasminogen activator inhibitor (PAI-1) and fibrinolysis activity and (ELT) were determined. We found significant differences in clinical examinations (higher blood pressure and ECG disturbances more frequently), HDL-Ch and HDL2-Ch plasma level was lower in children with positive family history than in control children. Multiple regression analysis of parental variables demonstrated, that children's TG and ELT are strongly determined by parental lipids and haemostasis parameters in children with positive family history of HTG.

Adult↗

[Effect of dietetic recommendations on the level of some lipid and hemostatic parameters in offspring of parents with risk factors for coronary heart disease].

Atherosclerosis, the precursor of coronary heart disease may originate in childhood. The atherogenic potential of food is related to its cholesterol and saturated-fat content. The study population consisted of children from CHD-parents under the age 12 years with plasma total cholesterol > 170 mg/dl, LDL-Ch > 90 mg/dl and ApoB > 70 mg/dl. All the patients were advised a 6 month diet following National Program of Cholesterol Prevention recommendation. Plasma, TCh, LDL-Ch, ApoB, TG, Ch-esters saturated/unsaturated ratio and platelet factor 4 concentration decreased, LCAT activity and Ch-esters unsaturated increased during study period. We observed interesting correlation between: PF4 and ApoB, PF4 and LDL-Ch and PF4 and HDL-ECh 18:3. Our data show, that proper diet can modify risk factors of CHD in children with family history of CHD.

Apolipoproteins B↗

Effect of LH and prolactin on steroid secretion by perifused luteal tissue from pregnant gilts with induced hypoprolactinemia or after passive immunoneutralization of LH.

The study was performed using luteal tissue obtained from 24 pregnant gilts. Group I was treated with bromocriptine (BR) from 37th to 42nd day of gestation. Group II was treated with homologous anti-pLH serum from 37th to 42nd day of pregnancy. Group III was given BR from 67th to 72nd day of gestation. Group IV received anti-pLH serum from 67th to 72nd day of pregnancy. The effect of exogenous LH or prolactin (100 ng/ml) on secretion of progesterone (P4) and estradiol (E2) by luteal tissue was studied using perifusion technique. Prolactin caused a significant (P < 0.05) increase in P4 secretion by luteal tissue from gilts in groups I and IV. Both LH and prolactin decreased (P < 0.05) estradiol secretion by luteal tissue obtained from gilts from group IV. Luteinizing hormone stimulated (P < 0.05) P4 and E2 secretion by luteal tissue from gilts from groups IV and II, respectively. The results demonstrate that both LH and prolactin have a regulatory role in steroid secretion by luteal tissue of gilts in the mid- and late periods of pregnancy.

Animals↗

Nutrition-endocrine interrelationships in the lactating and weaned sow.

Previous studies had identified the effects of nutrient restriction on delayed occurrence of estrus when body condition is low at farrowing or levels of intake fall below 2.5 kg (8.35 Mcal ME/h/d) during lactation. It appears that the failure via the GnRH pulse generator to stimulate sufficient LH pulsatility to trigger steroidogenesis may play a major role in the lack of reinitiation of cyclicity. Base-line concentrations, because of their variability between individual animals, may not be a major factor in predicting the time to return to estrus. Prolactin appears to be definitely antigonadotropic during lactation but may be involved in folliculogenesis effects during the postweaning period. Previous results would indicate that metabolic factors in concert with the major reproductive hormones play a key role in reestablishing the cycle postweaning. To achieve a greater understanding of the complexities of these two systems--nutrition and reproduction-greater emphasis must be placed on more precisely regulating the integral factors modulating the return to cyclic behavior.

Animals↗

[Changes in the visual system of children with subacute sclerosing panencephalitis].

The results of ophthalmological examinations were compared in 20 children aged 6 to 13 years with SSPE. The examinations in the first phase of the disease demonstrated fundus changes with presence of choked disc in 4 cases, papilloedema in 4 cases, uveitis in 1 case, retrobulbar optic neuritis in 1 case (in this case ophthalmological changes developed 4 months prior to the onset of typical neurological sings.

Adolescent↗

[Pseudotumor cerebri in children].

The authors observed 6 cases of brain pseudotumours in children aged from 3 to 15 years. All patients had been referred with the diagnosis of brain tumour, with headaches, eye fundus changes fundus changes. Some children had nystagmus, squint, vomiting and dizziness. One child had pharyngitis, two had sinusitis. Contrast brain examinations gave normal results. Diet with salt and fluid restriction and oedema-reducing drugs (glycerol, mannitol, decadron) were used. In all patients the neurological and ophthalmological signs regressed within 3 to 12 weeks.

Adolescent↗

Effect of bromocriptine administration during mid-pregnancy on the ovary function in the pig.

Plasma concentrations of prolactin, luteinizing hormone (LH), progesterone, estradiol-17 beta and androgens testosterone with dihydrotestosterone were determined in pregnant gilts (n = 6) administered bromocriptine (BR) from 37-42 days of pregnancy. Blood samples were daily taken at 2h-intervals from day 34 to 45 of pregnancy. BR treatment reduced (p less than 0.001) prolactin secretion from 14.8 +/- 0.9 ng/ml to 8.6 +/- 1.1 and 5.5 +/- 0.7 during the initial 1-3 and 4-6 days of treatment, respectively. Following cessation of BR treatment prolactin returned to the pre-treatment concentrations (14.5 +/- 1.0). BR did not alter LH during the first 3 days of treatment but decreased LH on days 4-6 (1.5 +/- 0.1 vs 2.1 +/- 0.2, p less than 0.05). Bromocriptine evoked a 20% increase (p less than 0.05) in estradiol-17 beta during days 1-3 following onset of treatment, however it suppressed androgen concentrations from 10.7 +/- 1.2 to 5.6 +/- 0.4 pg/ml in the same period. Suppression of prolactin from day 37-42 with a concurrent decrease of LH from day 40-42 of gestation did not affect maintenance of pregnancy and surprisingly was associated with a temporary elevation of progesterone. We conclude that prolactin has no luteotrophic properties during midpregnancy in gilts.

Animals↗

Effect of bromocriptine administration on maintenance of late pregnancy in the pig.

Plasma concentrations of prolactin, luteinizing hormone (LH) and progesterone were determined in pregnant gilts (n = 6) administered bromocriptine from 67-72 days of pregnancy. Blood samples were taken daily at 2 h intervals from 60 to 80 days of pregnancy. Bromocriptine treatment reduced prolactin from 9.7 +/- 1.4 before to 1.9 +/- 0.6 ng/ml during the treatment (p less than or equal to 0.05) and then returned to the pre-treatment concentrations (10.5 +/- 2.0) following cessation of bromocriptine. Bromocriptine increased LH from 1.4 +/- 0.2 before treatment to 2.9 +/- 0.5 ng/ml (p less than or equal to 0.01) during administration and maintained elevated (3.0 +/- 0.7) in the post-treatment period (p less than or equal to 0.05). Administration of bromocriptine did not alter progesterone concentration in plasma (7.5 +/- 1.2; 7.2 +/- 1.6 and 6.6 +/- 1.6 ng/ml in pretreatment, treatment and post-treatment periods, respectively). This study shows that decrease of prolactin level by bromocriptine treatment does not cause depletion of progesterone secretion in late pregnant pigs.

Animals↗

Active and passive immunization against luteinizing hormone in pigs.

Active immunization of four adult pigs with highly purified porcine luteinizing hormone (pLH)--using method of multiside intradermal injections--has been performed and resulted in the production of specific antibodies. Immunization caused prolongation of estrous cycle to 47-49 days in two gilts and to 26 days in the other ones. Obtained anti-pLH pig serum was administered intravenously to 40 day pregnant gilt during 5 days (10 ml of serum, twice daily). Blood plasma progesterone (P4) concentrations decreased significantly from 8-13 to 2-4 ng/ml after two days of infusion and remained at this level for the next 5 days. Administration of this anti-pLH pig serum to gilt in the luteal phase of the estrous cycle caused the inhibition P4 to undetectable amounts. The different results were found after the passive immunization of 40 day pregnant gilt with rabbit anti-pLH globulin preparation (5 days, equivalent to 3 ml of original undiluted serum, twice daily). Although after two days of infusion P4 concentration decreased, in the next days P4 level slowly increased to pretreatment concentrations. The data suggest the possibility of specific anti-pLH antibody production in pigs by using active immunization, and the repeated utilization of such obtained antiserum in the same species for the inhibition of corpus luteum (CL) function.

Animals↗