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781.
Maciorkowska E Roszko I Kowalczuk O Kaczmarski M Chyczewski L Kemona A 《Folia histochemica et cytobiologica / Polish Academy of Sciences, Polish Histochemical and Cytochemical Society》2007,45(3):215-219
The frequency of Helicobacter pylori infection in population can depend on the organism resistance, genetic condition, and bacterial strains virulence. A vacA gene, of mosaic structure, which encodes vacuolating cytotoxin is one of the known genes of H. pylori. The existence of several different genotypes of s and m regions enables the formation of numerous combinations of vacA gene genome. The studies on vacA genotype revealed that the frequency of occurrence of H. pylori containing s1 or s2, as well as m1 and m2 alleles varies in different parts of the world. The aim of the studies performed in the group of children and adults was to evaluate the prevalence of particular vacA gene alleles distribution in the population of the Podlasie province. The allele s1, which occurred in 84.3% of the examined group (86.8% in children and 81.3% in adults), turned out to be the most frequently observed of the signal encoding region. Statistically significant differences in s1 and s2 alleles distribution in relation to a dwelling place were not detected. The allele m2 (42.1% in children and 59% in adults) was the allele of midregion, most frequently occurring in our studies. The allele m2 was observed more often in H. pylori strains in the inhabitants from the urban areas (data statistically significant). 相似文献
782.
Walczak-Jedrzejowska R Slowikowska-Hilczer J Marchlewsk K Oszukowska E Kula K 《Folia histochemica et cytobiologica / Polish Academy of Sciences, Polish Histochemical and Cytochemical Society》2007,45(Z1):S59-S64
During establishment of spermatogenesis at the prepubertal age, an early germ cells apoptotic wave occurs likely aimed to remove abnormal germ cells and to maintain a proper cell number ratio between maturating germ cells and Sertoli cells. Here we assessed Sertoli and germ cell apoptosis in relation to morphological parameters of Sertoli cell maturation in neonatal rats under the influence of testosterone, estradiol and FSH given alone or in combinations. From postnatal day (PND) 5th to 15th male rats were daily injected with: 1) 2.5 mg of testosterone propionate (TP), or 2) 12.5 microg of 17beta-estradiol benzoate (EB), or 3) TP+EB, or 4) 7.5 IU of human purified FSH (hFSH), or 5) hFSH+EB or solvents (control-C). Autopsy was performed on PND 16th. Sertoli cell nuclei area and incidence of seminiferous tubule lumen formation (LF) were taken as markers of Sertoli cell maturation. Sertoli and germ cell apoptosis was assessed using TUNEL method. In comparison with C, the area of Sertoli cell nuclei was significantly reduced after EB (25.7+/-2.0 vs. 30.9+/-1.6 microm2 for C, p<0.001) and increased after hFSH+EB (33.1+/-2.3 microm2, p<0.05). Incidence of LF was completely arrested by steroid hormone treatments given separately, significantly inhibited after TP+EB (median: 0.0%, vs. 2.0% for C p<0.05) and significantly enhanced after hFSH+EB (median: 51.0%, p<0.001). hFSH alone did not influence LF. Incidence of TUNEL positive Sertoli cells significantly increased after EB (median: 2.9% vs. 0.5% for C, p<0.05) or TP+EB (median: 2.2%, p<0.01) and was not affected by other treatments. Incidence of TUNEL positive germ cells increased significantly after EB alone (median: 4.4% vs. 2.5%, for C, p<0.01 ) and was significantly decreased by hFSH+EB (median: 0.5%, p<0.01). CONCLUSIONS: 1) Administration of testosterone or estradiol to immature rats inhibits Sertoli cell maturation. 2) Estradiol stimulates Sertoli and germ cell apoptosis while testosterone has no effect. 3) Testosterone eliminates estradiol--induced germ cell apoptosis when both hormones act in concert. 4) FSH in concert with estradiol, but neither one of the hormone alone, accelerate Sertoli cell differentiation and effectively inhibit germ cell apoptosis. 5) During seminiferous tubule maturation testosterone and the synergistic action of FSH with estradiol support germ cell survival while estradiol alone has an inhibitory, pro-apoptotic effect. 相似文献
783.
Błachut-Okrasińska E Bojarska E Stepiński J Antosiewicz JM 《Biophysical chemistry》2007,129(2-3):289-297
The kinetics of binding of five analogues of the 5'-mRNA cap, differing in size and electric charge, to the eukaryotic initiation factor eIF4E, at 20 degrees C, pH 7.2, and ionic strength of 150 mM, were measured, after mixing solutions of comparable concentrations of the reagents, in a stopped-flow spectrofluorimeter. The registered stopped-flow signals were fitted using an efficient software package, called Dyna Fit, based on a numerical solution of the kinetic rate equations for assumed reaction mechanisms. One-, two-, and three-step binding models were considered. The quality of fits for these models were compared using two statistical criteria: Akaike's Information Criterion and Bayesian Information Criterion. Based on resulting probabilities of the models, it was concluded that for all investigated ligands a one-step binding model has essentially no support in the experimental observations. Our conclusions were also analysed from the perspective of kinetic transients obtained for cap-eIF4E systems under the so called pseudo-first order reaction condition, which result in the linear correlation of the observed association rate constant with ligand concentration. The existence of such a linear correlation is usually considered as proof of a one-step binding mechanism. The kinetic and optical parameters, derived from fitting a two-step cap-binding model with the DynaFit, were used to simulate kinetic transients under pseudo-first order reaction conditions. It appeared that the observed association rate constants derived from these simulated transients are also linearly correlated with the ligand concentration. This indicated that these linear dependencies are not sufficient to conclude a one-step binding. 相似文献
784.
Hairpin structure within the 3'UTR of DNA polymerase beta mRNA acts as a post-transcriptional regulatory element and interacts with Hax-1
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785.
Olszanecka-Glinianowicz M Zahorska-Markiewicz B Kocełak P Janowska J Semik-Grabarczyk E 《Endokrynologia Polska》2007,58(5):422-425
INTRODUCTION: The aim of the present study was to examine the response of plasma orexin and ghrelin to the oral glucose tolerance test (OGTT) in obese women without additional disease. MATERIAL AND METHODS: The study group comprised 15 obese women aged 30.4+/-9.7 years of mean BMI 34.7+/-3.8 kg/m(2). The measurements were performed after an overnight fast and 30, 60 and 120 minutes after the oral administration of 75 grams of glucose. Serum concentrations of ghrelin and orexin A were measured by an enzyme-linked immunosorbent assay (ELISA) kit. Serum concentrations of insulin were measured by radioimmunoassay (RIA). Plasma glucose was determined by an enzymatic procedure. Body composition was determined by impedance analysis using Bodystat. RESULTS: We observed no significant differences between serum concentrations of ghrelin and orexin during OGTT. No correlations were found between serum ghrelin and orexin concentrations and serum insulin and glucose concentrations in any of the measurements. CONCLUSION: Oral glucose administration did not change serum concentrations of ghrelin and orexin A in obese women without additional disease. 相似文献
786.
Korzonek-Szlacheta I Wielkoszyński T Stanek A Swietochowska E Karpe J Sieroń A 《Endokrynologia Polska》2007,58(1):27-32
INTRODUCTION: The study was undertaken to determine blood serum concentrations of selected steroid hormones (estradiol--E(2), testosterone--T, dehydroepiandrosterone sulfate--DHEA-S) and luteinizing hormone (LH) in professional footballers subjected to whole body cryotherapy. MATERIAL AND METHODS: Twenty-two clinically healthy males, mean age 26.7 years, were studied. The subjects underwent ten sessions of whole body cryotherapy in Wroclaw-type chamber, with kinesitherapy following each session. Blood samples were collected before and two days after the treatment and the results were analyzed statistically. RESULTS: After the treatment there was a significant decrease in the concentrations of T (6.01 vs. 4.80 ng/mL, p < 0.01) and E(2) (102.3 vs. 47.5 pg/mL, p < 0.00001), but no DHEA-S and LH. The T/E(2) ratio showed a significant increase form 72.2 to 136.5 (p < 0.01). CONCLUSIONS: Whole body cryotherapy leads to a significant decrease in serum T and E(2), with no effect on LH and DHEAS levels. As a results of cryotherapy, the T/E(2) ratio was significant increased. The changes observed are probably due to cryotherapy-induced alternation in the blood supply to the skin and subcutaneous tissue, as well as to modulation of the activity of aromatase which is responsible for conversion of testosterone and androstenedione to estrogens. 相似文献
787.
788.
Simultaneous LC/ESI‐MS Separation Method for the Enantioseparation of Some New Anticonvulsant Drugs
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A sensitive and specific method for the simultaneous determination of the enantiomeric purity of 2,6‐dimethylphenoxyacetyl derivatives as trans or cis racemic and enantiomeric forms with 2‐ or 4‐aminocyclohexanol moiety ( 1 , 2 , 3 , 6 ) and their amine analogs ( 8 , 9 ) was developed. The compounds studied are known for their anticonvulsant activity and the most interesting pharmacological results were those for (±)‐trans‐2‐(2,6‐dimethylphenoxy)‐N‐(2‐hydroxycyclohexyl)acetamide ( 1 ) as well as (±)‐trans‐2‐[(2,6‐dimethylphenoxy)ethyl]aminocyclohexanol ( 8 ). The analytical method for determining the enantiomeric purity of the compounds studied is based on direct separation of the analytes using a chiral stationary phase (Chiralpak AS column). The mass spectrometric analysis was done on a coupled liquid chromatograph–mass spectrometer system with an electrospray ionization source (LC/ESI‐MS). For the compounds 1 , 8 , and 9 , the method allows an excellent separation of enantiomers, with a resolution higher than 3.2, and a tailing factor of less than 1.67 with a final enantiomer purity better than 97.5%. Chirality 26:144–149, 2014. © 2014 Wiley Periodicals, Inc. 相似文献
789.
Justyna Czech-Kowalska Julita Latka-Grot Dorota Bulsiewicz Maciej Jaworski Pawel Pludowski Grazyna Wygledowska Bogdan Chazan Beata Pawlus Anna Zochowska Maria K. Borszewska-Kornacka Elzbieta Karczmarewicz Edyta Czekuc-Kryskiewicz Anna Dobrzanska 《PloS one》2014,9(9)
Objective
The optimal vitamin D intake for nursing women is controversial. Deterioration, at least in bone mass, is reported during lactation. This study evaluated whether vitamin D supplementation during lactation enhances the maternal and infant’s vitamin D status, bone mass and body composition.Design and Methods
After term delivery, 174 healthy mothers were randomized to receive 1200 IU/d (800 IU/d+400 IU/d from multivitamins) or 400 IU/d (placebo+400 IU/d from multivitamins) of cholecalciferol for 6 months while breastfeeding. All infants received 400 IU/d of cholecalciferol. Serum 25-hydroxyvitamin D [25(OH)D], iPTH, calcium, urinary calcium, and densitometry were performed in mother-offspring pairs after delivery, and at 3 and 6 months later.Results
A total of 137 (79%) (n = 70; 1200 IU/d, n = 67; 400 IU/d) completed the study. 25(OH)D was similar in both groups at baseline (13.7 ng/ml vs. 16.1 ng/ml; P = 0.09) and at 3 months (25.7 ng/ml vs. 24.5 ng/ml; P = 0.09), but appeared higher in the 1200 IU/d group at 6 months of supplementation (25.6 ng/ml vs. 23.1 ng/ml; P = 0.009). The prevalence of 25(OH)D <20 ng/ml was comparable between groups at baseline (71% vs. 64%, P = 0.36) but lower in the 1200 IU/d group after 3 months (9% vs. 25%, P = 0.009) and 6 months (14% vs. 30%, P = 0.03). Maternal and infants’ iPTH, calciuria, bone mass and body composition as well as infants’ 25(OH)D levels were not significantly different between groups during the study. Significant negative correlations were noted between maternal 25(OH)D and fat mass (R = −0.49, P = 0.00001), android fat mass (R = −0.53, P = 0.00001), and gynoid fat mass (R = −0.43, P = 0.00001) after 6 months of supplementation.Conclusions
Vitamin D supplementation at a dose of 400 IU/d was not sufficient to maintain 25(OH)D >20 ng/ml in nursing women, while 1200 IU/d appeared more effective, but had no effect on breastfed offspring vitamin D status, or changes in the bone mass and the body composition observed in both during breastfeeding.Trial Registration
ClinicalTrials.gov NCT01506557相似文献790.
Joanna Kowalska Anna Wypijewska?del?Nogal Zbigniew M. Darzynkiewicz Janina Buck Corina Nicola Andreas N. Kuhn Maciej Lukaszewicz Joanna Zuberek Malwina Strenkowska Marcin Ziemniak Maciej Maciejczyk Elzbieta Bojarska Robert E. Rhoads Edward Darzynkiewicz Ugur Sahin Jacek Jemielity 《Nucleic acids research》2014,42(16):10245-10264
Modified mRNA cap analogs aid in the study of mRNA-related processes and may enable creation of novel therapeutic interventions. We report the synthesis and properties of 11 dinucleotide cap analogs bearing a single boranophosphate modification at either the α-, β- or γ-position of the 5′,5′-triphosphate chain. The compounds can potentially serve either as inhibitors of translation in cancer cells or reagents for increasing expression of therapeutic proteins in vivo from exogenous mRNAs. The BH3-analogs were tested as substrates and binding partners for two major cytoplasmic cap-binding proteins, DcpS, a decapping pyrophosphatase, and eIF4E, a translation initiation factor. The susceptibility to DcpS was different between BH3-analogs and the corresponding analogs containing S instead of BH3 (S-analogs). Depending on its placement, the boranophosphate group weakened the interaction with DcpS but stabilized the interaction with eIF4E. The first of the properties makes the BH3-analogs more stable and the second, more potent as inhibitors of protein biosynthesis. Protein expression in dendritic cells was 2.2- and 1.7-fold higher for mRNAs capped with m27,2′-OGppBH3pG D1 and m27,2′-OGppBH3pG D2, respectively, than for in vitro transcribed mRNA capped with m27,3′-OGpppG. Higher expression of cancer antigens would make mRNAs containing m27,2′-OGppBH3pG D1 and m27,2′-OGppBH3pG D2 favorable for anticancer immunization. 相似文献