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101.
Staszkiewicz J Skowronski MT Kaminski T Siawrys G Krazinski BE Kusmider M Przala J Okrasa S 《Animal reproduction science》2007,101(1-2):97-112
Previous studies have demonstrated the presence of endogenous opioid peptides (EOP) in the ovary and suggested their implication in local interactions within ovarian structures. Nevertheless, data pertaining to the expression of genes, coding for the opioid precursors, in ovarian cells are still rudimentary and not available for the pig. The study was undertaken to test whether genes of the opioid precursors - proopiomelanocortin (POMC), proenkephalin (PENK) and prodynorphin (PDYN) - are expressed in non-treated and gonadotropin-treated theca and granulosa cells isolated from ovarian follicles of the pig. The cells were isolated from small (days 15-16 of the estrous cycle) and large (days 19-20) porcine follicles. Dispersed cells were cultured in Eagle's medium under the water saturated atmosphere of 95% air and 5% CO(2), in the presence or absence of respective gonadotropin; theca cells with LH (100 ng/ml) and granulosa cells with FSH (100 ng/ml). Following 24h-incubation, the cells were harvested and the total RNA was isolated. The expression of genes coding for opioid precursors was estimated by the semi-quantitative RT-PCR technique involving co-amplification of the target cDNA (POMC, PENK or PDYN) and control cDNA (beta-actin or 18S rRNA). Specificities of PCR products were confirmed by Southern analysis and sequencing. In theca cells the expression of opioid precursors appeared to be gonadotropin-dependent except for PENK in the cells isolated from large follicles. In turn, granulosa cells exhibited the expression of POMC and PENK genes independently on treatment with FSH. This gonadotropin induced the expression of PDYN gene in granulosa cells isolated from small and large follicles and significantly increased POMC mRNA content in the cells from the large ones. The present studies indicate that porcine follicular cells (especially granulosa cells) may produce opioid peptides and that gonadotropins may modulate gene expression of their precursors in these cells. Moreover, our results support a participation of opioid peptides in the local regulations within ovarian follicle. 相似文献
102.
Stawerska R Smyczyńska J Hilczer M Kowalska E Lewiński A Karasek M 《Endokrynologia Polska》2007,58(4):282-290
INTRODUCTION: Prolactin (Prl) is secreted in a circadian pattern, although no method of interpreting it has yet been established. The aim of the study was to assess Prl secretion in children on the basis of the Prl circadian profile and to establish principles for the interpretation of the results obtained by this method. MATERIAL AND METHODS: The analysis comprised 41 healthy short children (25 boys); aged 5.2-16.3 years, in whom hormonal disorders and chronic diseases had been excluded. The children were divided into prepubertal or pubertal subgroups. Serum Prl concentrations were measured every 3 hours for 24 hours. To assess the rhythm the parameters of macroscopic analysis were calculated and receiver operating characteristic (ROC) analysis was performed. The group for comparison consisted of 30 children aged 8.9-17.2 years with hyperprolactinaemia. RESULTS: In each subgroup significantly higher Prl concentrations were observed at night than by day. No statistical differences were noticed between the groups regarding Prl concentrations at particular time points or parameter values during circadian Prl rhythm evaluation. In the group analysed weak correlations were found between age and Prl peak and trough levels. On the basis of ROC analysis criteria for the existence of normal circadian Prl rhythm in children were established. CONCLUSIONS: 1. The presence of normal circadian Prl rhythm is observed if at least one of the following three criteria is fulfilled: amplitude >1.8779; X(n)/X(d) ratio >1.685; regression index <-0.4107. 2. No interpretation in relation to sex, age and stage of puberty is necessary for the circadian prolactin secretion rhythm in children. 相似文献
103.
The conversion of and toxic effects exerted by several mono- and dihalogenated C1 and C2 compounds on cultures of Xanthobacter autotrophicus GJ10 growing on 1,2-dichloroethane were investigated. Bromochloromethane, dibromomethane and 1-bromo-2-chloroethane were
utilized by strain GJ10 in batch culture as a cosubstrate and sole carbon source. The rate of degradation of dihalomethanes
by whole cells was lower than that of 1,2-dichloroethane, but a significant increase of the rate of dihalomethane biodegradation
was observed when methanol or ethanol were added as a cosubstrate. Products of the degradation of several tested compounds
by haloalkane dehalogenase were analyzed and a new metabolic pathway based on hydrolytic conversion to formaldehyde was proposed
for the dihalomethanes. Strain GJ10 growing on 1,2-dichloroethane converted 2-fluoroethanol and 1-chloro-2-fluoroethane to
2-fluoroacetate, which was tolerated up to a concentration of 2.5 mM. On the basis of the results from batch cultures an inert
(dichloromethane), a growth-supporting (dibromomethane) and a toxic (1,2-dibromoethane) compound were selected for testing
their effects on a continuous culture of strain GJ10 growing on 1,2-dichloroethane. The compounds were added as pulses to
a steady-state chemostat and the response of the culture was followed. The effects varied from a temporary decrease in cell
density for dibromomethane to severe toxicity and culture washout with 1,2-dibromoethane. Our results extend the spectrum
of halogenated C1 and C2 compounds that are known to be degraded by strain GJ10 and provide information on toxic effects and
transformation of compounds not serving as a carbon source for this bacterium. 相似文献
104.
Piechota M Banach M Irzmański R Misztal M Rysz J Barylski M Piechota-Urbańska M Kowalski J Pawlicki L 《Cellular & molecular biology letters》2007,12(2):162-175
The aim of this study was to find the relationship between N-terminal brain natriuretic propeptide (NT-proBNP), procalcitonin
(PCT) and C-reactive protein (CRP) plasma concentrations in septic patients. This was a prospective study, performed at Medical
University Hospital No. 5 in łódź. Twenty patients with sepsis and severe sepsis were included in the study. N-terminal brain
natriuretic propeptide, procalcitonin and C-reactive protein concentrations, and survival were evaluated. In the whole studied
group (128 measurements), the mean NT-proBNP, procalcitonin and C-reactive protein concentrations were, respectively: 140.80±84.65
pg/ml, 22.32±97.41 ng/ml, 128.51±79.05 mg/l. The correlations for the NT-proBNP level and procalcitonin and C-reactive protein
levels were 0.3273 (p<0.001) and 0.4134 (p<0.001), respectively. NT-proBNP levels correlate with PCT and CRP levels in septic
patients. In the survivor subgroup, the mean NT-proBNP plasma concentrations were significantly lower than in the non-survivor
subgroup. 相似文献
105.
SNPs in the porcine <Emphasis Type="Italic">PPARGC1a</Emphasis> gene: Interbreed differences and their phenotypic effects 总被引:1,自引:0,他引:1
Stachowiak M Szydlowski M Cieslak J Switonski M 《Cellular & molecular biology letters》2007,12(2):231-239
Due to its function, the peroxisome proliferative activated receptor-γ, coactivator-1α (PPARGC1A) gene is a candidate in the search for genes that may affect production traits in the pig. The purpose of this study was
to screen for new SNPs in exon 8 of the porcine PPARGC1A gene and to test their possible association with production traits. Altogether 736 pigs representing five breeds Polish Landrace,
n=242; Polish Large White, n=192; Hampshire, n=27; Duroc, 21; Pietrain, n=12) and synthetic line 990 (n=242) were scanned
via SSCP assay. Four SNPs were found; two new ones: C/G (His338Gln) and G/A Thr359Thr), and two previously reported ones:
C/A (Arg369Arg) and T/A Cys430Ser). The missense T/A and C/G SNPs demonstrated pronounced interbreed variability in terms
of allele frequencies, including the exclusive presence of the C/G substitution in the Hampshire breed. The tested SNPs occurred
in five putative haplotypes, and their frequency also differed substantially between breeds. The association of the SNPs with
production traits was tested for G/A (Thr359Thr), C/A (Arg369Arg) and T/A (Cys430Ser) substitutions in Polish Large White,
Polish Landrace and line 990. The analysis revealed only breed-specific associations. The T/A (Cys430Ser) SNP was related
to the feed conversion ratio in the Polish Large White (P=0.02), and the silent G/A and C/A substitutions were respectively
associated with abdominal fat in line 990 and backfat thickness in Polish Landrace (P=0.04). The combined effects of the substitutions
were estimated as haplotype effects. Three significant contrasts between haplotypes were calculated, but the observed associations
were again only breed-specific. 相似文献
106.
Effects of litter traits,soil biota,and soil chemistry on soil carbon stocks at a common garden with 14 tree species 总被引:1,自引:0,他引:1
Kevin E. Mueller Sarah E. Hobbie Jon Chorover Peter B. Reich Nico Eisenhauer Michael J. Castellano Oliver A. Chadwick Tomasz Dobies Cynthia M. Hale Andrzej M. Jagodziński Izabela Kałucka Barbara Kieliszewska-Rokicka Jerzy Modrzyński Anna Rożen Maciej Skorupski Łukasz Sobczyk Małgorzata Stasińska Lidia K. Trocha January Weiner Anna Wierzbicka Jacek Oleksyn 《Biogeochemistry》2015,123(3):313-327
107.
Maciej Stolarski 《Biological Rhythm Research》2015,46(3):417-423
The aim of the present article is to determine whether recently shown positive relationships between self-reported emotional intelligence (EI) and morningess preference exist when EI is measured with an ability-based test. In two studies (study 1: N = 206 and study 2: N = 184), we applied two different morningness–eveningness questionnaires and a performance test of EI consisting of four dimensions (perception, understanding, assimilation, managing). The two studies provided similar results indicating that “night owls” have higher EI than “larks”; specifically, evening-oriented subjects showed greater ability in emotion perception and understanding, as compared to morning-oriented individuals. The obtained results were in line with hitherto existing research on chronotype and general intelligence. The results provide further evidence for a cognitive character of ability-based EI and accentuate its different nature when compared to self-reported EI. The main findings are discussed in terms of evolutionary theories of circadian preferences, EI and mental abilities. 相似文献
108.
Marta Kulik Anna?M. Goral Maciej Jasiński Paulina?M. Dominiak Joanna Trylska 《Biophysical journal》2015,108(3):655-665
Electrostatic interactions often play key roles in the recognition of small molecules by nucleic acids. An example is aminoglycoside antibiotics, which by binding to ribosomal RNA (rRNA) affect bacterial protein synthesis. These antibiotics remain one of the few valid treatments against hospital-acquired infections by Gram-negative bacteria. It is necessary to understand the amplitude of electrostatic interactions between aminoglycosides and their rRNA targets to introduce aminoglycoside modifications that would enhance their binding or to design new scaffolds. Here, we calculated the electrostatic energy of interactions and its per-ring contributions between aminoglycosides and their primary rRNA binding site. We applied either the methodology based on the exact potential multipole moment (EPMM) or classical molecular mechanics force field single-point partial charges with Coulomb formula. For EPMM, we first reconstructed the aspherical electron density of 12 aminoglycoside-RNA complexes from the atomic parameters deposited in the University at Buffalo Databank. The University at Buffalo Databank concept assumes transferability of electron density between atoms in chemically equivalent vicinities and allows reconstruction of the electron densities from experimental structural data. From the electron density, we then calculated the electrostatic energy of interaction using EPMM. Finally, we compared the two approaches. The calculated electrostatic interaction energies between various aminoglycosides and their binding sites correlate with experimentally obtained binding free energies. Based on the calculated energetic contributions of water molecules mediating the interactions between the antibiotic and rRNA, we suggest possible modifications that could enhance aminoglycoside binding affinity. 相似文献
109.
High cell density cultivation of Pseudomonas putida KT2440 using glucose without the need for oxygen enriched air supply
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110.
Francine Z Marques Simon PR Romaine Matthew Denniff James Eales John Dormer Ingrid M Garrelds Lukasz Wojnar Katarzyna Musialik Barbara Duda-Raszewska Bartlomiej Kiszka Magdalena Duda Brian J Morris Nilesh J Samani AH Jan Danser Pawel Bogdanski Ewa Zukowska-Szczechowska Fadi J Charchar Maciej Tomaszewski 《Molecular medicine (Cambridge, Mass.)》2015,21(1):739-748
MicroRNA-181a binds to the 3′ untranslated region of messenger RNA (mRNA) for renin, a rate-limiting enzyme of the renin-angiotensin system. Our objective was to determine whether this molecular interaction translates into a clinically meaningful effect on blood pressure and whether circulating miR-181a is a measurable proxy of blood pressure. In 200 human kidneys from the TRANScriptome of renaL humAn TissuE (TRANSLATE) study, renal miR-181a was the sole negative predictor of renin mRNA and a strong correlate of circulating miR-181a. Elevated miR-181a levels correlated positively with systolic and diastolic blood pressure in TRANSLATE, and this association was independent of circulating renin. The association between serum miR-181a and systolic blood pressure was replicated in 199 subjects from the Genetic Regulation of Arterial Pressure of Humans In the Community (GRAPHIC) study. Renal immunohistochemistry and in situ hybridization showed that colocalization of miR-181a and renin was most prominent in collecting ducts where renin is not released into the systemic circulation. Analysis of 69 human kidneys characterized by RNA sequencing revealed that miR-181a was associated with downregulation of four mitochondrial pathways and upregulation of 41 signaling cascades of adaptive immunity and inflammation. We conclude that renal miR-181a has pleiotropic effects on pathways relevant to blood pressure regulation and that circulating levels of miR-181a are both a measurable proxy of renal miR-181a expression and a novel biochemical correlate of blood pressure. 相似文献