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Quantitative Distribution (quantitative + distribution)
Selected AbstractsThe concentrations of fatty acids in organo-mineral particle-size fractions of a ChernozemEUROPEAN JOURNAL OF SOIL SCIENCE, Issue 3 2004G. Jandl Summary Fatty acids, the most abundant class of soil lipids, indicate pedogenetic processes and soil management. However, their quantitative distribution in organo-mineral particle-size fractions is unknown. The concentrations of n -C10:0 to n -C34:0 fatty acids both in whole soil samples and in the organo-mineral particle-size fractions of the Ap horizon of a Chernozem were determined (i) to evaluate the effects of long-term fertilization and (ii) to investigate their influence on the aggregation of organo-mineral primary particles. Quantification by gas chromatography/mass spectrometry (GC/MS) showed that long-term fertilization with nitrogen, phosphorus and potassium (NPK) and farmyard manure (FYM) led to larger concentrations (25.8 µg g,1) of fatty acids than in the unfertilized sample (22.0 µg g,1). For particle-size fractions of the unfertilized soil, the fatty acid concentrations increased from the coarse silt to the clay fractions (except for fine silt). Fertilization with NPK and FYM resulted in absolute enrichments of n -C21:0 to n -C34:0 fatty acids with a maximum at n -C28:0 in clay (×2.2), medium silt (×2.0), coarse silt (×1.8) and sand (×2.9) compared with the unfertilized treatment (the factors of enrichment are given in parentheses). New evidence for the aggregate stabilizing function of n -C21:0 to n -C34:0 fatty acids was shown by the characteristic pattern in size-fractionated, disaggregated and aggregated samples. Highly significant correlations of fatty acid concentrations with organic C concentrations and specific surface areas are interpreted as indicators of (i) trapping of fatty acids in organic matter macromolecules and (ii) direct bonding to mineral surfaces. This interpretation was supported by the thermal volatilization and determination of fatty acids by pyrolysis-field ionization mass spectrometry (Py-FIMS). [source] Influence of Temperature on the Liver Circadian Clock in the Ruin Lizard Podarcis siculaMICROSCOPY RESEARCH AND TECHNIQUE, Issue 7 2007Manuela Malatesta Abstract Reptiles represent an interesting animal model to investigate the influence of temperature on molecular circadian clocks. The ruin lizard Podarcis sicula lives in a continental climate and it is subjected to wide range of environmental temperatures during the course of the year. As consequence, ruin lizard daily activity pattern includes either the hibernation or periods of inactivity determined by hypothermia. Here we showed the rhythmic expression of two clock genes, lPer2 and lClock, in the liver of active lizards exposed to summer photo-thermoperiodic conditions. Interestingly, the exposition of lizards to hypothermic conditions, typical of winter season, induced a strong dampening of clock genes mRNA rhythmicity with a coincident decrease of levels. We also examined the qualitative and quantitative distribution of lPER2 and lCLOCK protein in different cellular compartments during the 24-h cycle. In the liver of active lizards both proteins showed a rhythmic expression profile in all cellular compartments. After 3 days at 6°C, some temporal fluctuations of the lCLOCK and lPER2 are still detectable, although, with some marked modifications in respect to the values detected in the liver of active lizards. Besides demonstrating the influence of low temperature on the lizard liver circadian oscillators, present results could provide new essential information for comparative studies on the influence of temperature on the circadian system across vertebrate classes. Microsc. Res. Tech., 2007. © 2007 Wiley-Liss, Inc. [source] ,-globin DNA in maternal plasma as a molecular marker of pre-eclampsiaPRENATAL DIAGNOSIS, Issue 9 2004Akihiko Sekizawa Abstract Objectives Levels of cell-free foetal DNA in maternal plasma are higher in the presence of clinical features of pre-eclampsia (PE). However, currently, this method is informative only in women bearing a male foetus, by amplification of Y-specific sequences. In the present study, we overcame this limitation by examining quantitative distribution of ,-globin, a foetal gender,independent DNA marker. Methods We quantified ,-globin concentrations in the plasma of 207 pregnant women: control group, 164 subjects; affected group, 43 women affected by PE (n = 43). ,-globin concentrations were converted into multiples of the median of the controls (MoM), in order to assess the possible different distribution of ,-globin MoM in cases and controls. Results Adjusted MoM values were as follows: controls, 1.00 ± 0.71; affected group 4.03 ± 3.77 (p -value < 0.001). Among the PE affected cases, MoM ,-globin values of cases with foetal growth restriction (FGR) were almost twice as great as those cases without FGR (p -value = 0.003). Conclusion ,-globin levels are higher in the plasma of pregnant women with PE, especially in those cases complicated with FGR, and do not depend on foetal gender. Such a molecular marker can potentially be used in evaluating the pathophysiological severity of PE. Copyright © 2004 John Wiley & Sons, Ltd. [source] Application of cycling index and input-output environs for interpretation of nutrient flows in mixed rice-beef production systems in JapanANIMAL SCIENCE JOURNAL, Issue 3 2009Yusuke TABATA ABSTRACT The objective of the present study was to apply two methods developed in ecology, the cycling index and input-output environs, to interpret nutrient flows in mixed rice-beef production systems. The cycling index (CI) was a quantitative measure of nutrient cycling. It was defined as the proportion of cycled nutrients to the total amount of nutrient flows. On the other hand, the input-output environs provide a quantitative distribution on a particular input or output. In this study, these methods were applied to the nutrient flows in the mixed rice-beef production systems in Japan. The results of CI provided information on the effects of nutrient cycling on the efficient conversion of nutrient imports to nutrient export. The results of input-output environs indicated that the indices represent indirect effects provided by the interaction between rice and beef production. In conclusion, these methods indicated new findings on nutrient utilization in the systems. The results of this study implied the further applicability of these two methods to the study of nutrient flows in mixed crop-animal production systems. [source] A quantitative study on arginine catabolism by mixed ruminal bacteria, protozoa and their mixture in vitroANIMAL SCIENCE JOURNAL, Issue 1 2003Halima SULTANA ABSTRACT The catabolism of arginine (Arg) by mixed rumen bacteria (B), mixed rumen protozoa (P), and their mixture (BP) was quantitatively investigated in an in vitro system in order to confirm the metabolic pathway of Arg and provide basic information for enzymatic and molecular studies as well as an understanding of the quantitative distribution of metabolites. Rumen microbial suspensions (B, P, and BP) collected from fistulated goats were anaerobically incubated with or without 1 mmol/L Arg at 39°C for 12 h. Arg and other related compounds such as citrulline (Cit), ornithine (Orn), proline (Pro) and 5-aminovaleric acid (5AV) in both supernatant and hydrolyzates of B, P, and BP suspensions were analyzed by HPLC. The metabolic pathways of Arg in mixed rumen bacteria and mixed rumen protozoa were considered to be as follows: rumen bacteria, Arg , Cit , Orn , Pro , 5AV , VFAs + NH3; rumen protozoa, Arg , Cit , Orn , Pro , 5AV. The disappearance of Arg (1 mmol/L) was approximately 52.9 and 88.2% in B, 33.9 and 55.6% in P, and 52.8 and 85.2% in BP during 6 and 12 h incubations, respectively. When expressed in units of ,per gram (g) of microbial nitrogen (MN)', the net degradation rate of Arg in BP (50.3 µmol/g MN/h) was approximately 46% lower than that of B during a 12 h incubation period. The presence of protozoa tended to inhibit the production of Orn from Cit and the production of 5AV from Pro which were thought to be rate-limiting steps of Arg metabolism in rumen microorganisms. As a result, protozoa appeared to have a saving effect on Arg metabolism, that is, protozoa protected Arg from wasteful exhaustion in the rumen. [source] Pharmacology and autoradiography of human DP prostanoid receptors using [3H]-BWA868C, a DP receptor-selective antagonist radioligandBRITISH JOURNAL OF PHARMACOLOGY, Issue 6 2000N A Sharif A potent and highly selective DP prostanoid receptor antagonist radioligand, [3H]-cyclohexyl-N-BWA868C (3-benzyl-5-(6-carboxyhexyl)-1-(2-cyclohexyl-2-hydroxyethyl-amino) hydantoin, ([3H]-BWA868C)), has been generated for receptor binding and autoradiographic studies. Specific [3H]-BWA868C binding to human platelet membranes achieved equilibrium within 60 min at 23°C and constituted up to 95% of the total binding. The association (K+1) and dissociation (K,1) rate constants of binding were 0.758±0.064 min,1, mmol and 0.0042±0.0002 min,1, respectively, yielding dissociation constants (KDs) of 5.66±0.44 nM (n=4). Specific [3H]-BWA868C bound to DP receptors with a high affinity (KD=1.45±0.01 nM, n=3) and to a finite, saturable number of binding sites (Bmax=21.1±0.6 nmol g,1 wet weight). DP receptor class prostanoids (e.g. ZK118182, BW245C, BWA868C, PGD2) exhibited high (nanomolar) affinities for [3H]-BWA868C binding, while prostanoids selective for EP, FP, IP and TP receptors showed a low (micromolar) affinity. Specific DP receptor binding sites were autoradiographically localized on the ciliary epithelium/process, longitudinal and circular ciliary muscles, retinal choroid and iris in human eye sections using [3H]-BWA868C. While [3H]-PGD2 yielded similar quantitative distribution of DP receptors as [3H]-BWA868C, the level of non-specific binding observed with [3H]-PGD2 was significantly greater than that observed with [3H]-BWA868C. It is concluded that [3H]-BWA868C is a high-affinity and very specific DP receptor radioligand capable of selectively labelling the DP receptor. [3H]-BWA868C may prove useful for future homogenate-based and autoradiographic studies on the DP receptor. British Journal of Pharmacology (2000) 131, 1025,1038; doi:10.1038/sj.bjp.0703686 [source] Quantification and characterization of GABA-ergic amacrine cells in the retina of GAD67-GFP knock-in miceACTA OPHTHALMOLOGICA, Issue 4 2008Christian Albrecht May Abstract. Purpose:, Although the presence of ,-aminobutyrate acid (GABA) in amacrine cells and its co-localization with other neuronal substances is well known, there exists only little information about their quantitative distribution in the mouse eye. The aim of the present study was to characterize GABA-ergic amacrine cells in the retina of the recently introduced glutamate decarboxylase 67-green fluorescent protein (GAD67-GFP) knock-in mouse. Methods:, Whole mounts of the retina were prepared and the GFP-positive neurons quantified. Immunofluorescence staining was performed with antibodies against GABA, calbindin (CB), calretinin (CR), parvalbumin (PV), choline acetyl transferase (ChAT), tyrosine hydroxylase (TH), vesicular glutamate transporter (VGluT) 1, VGluT2 and VGluT3. Results:, Displaced GABA-ergic amacrine cells in the ganglion cell layer (GCL) showed a density of 1006 ± 170 cells/mm2. In the inner nuclear layer (INL), the density of amacrine cells was 8821 ± 448 cells/mm2 in the central region and 6825 ± 408 cells/mm2 in the peripheral region. GFP-positive amacrine cells co-localized with GABA (99%), CR (INL 18%, GCL 71.3%), CB (INL 6.3%), bNOS (INL 1%, GCL 4%), and ChAT (INL 17%, GCL 92.6%). No co-localization was seen with antibodies against PV, TH, and VGluT 1-3. Conclusions:, This study presents the first quantitative data concerning the co-localization of GABA-ergic neurons in the mouse retina with various neuronal markers. [source] Cell-free mRNA concentrations of CRH, PLAC1, and selectin-P are increased in the plasma of pregnant women with preeclampsiaPRENATAL DIAGNOSIS, Issue 8 2007Yuditiya Purwosunu Abstract Objective To compare mRNA concentrations of corticotrophin-releasing hormone (CRH), placenta specific-1 (PLAC1), and selectin-P in preeclamptic and normal pregnancies. Methods Peripheral blood samples were obtained from 43 pregnant women with preeclampsia and 41 control subjects. Plasma was harvested from samples and RNA extracted. Plasma RNA was analyzed using reverse transcription polymerase chain reaction (PCR) assay. Median concentrations of CRH, PLAC1, and selectin-P mRNA in plasma were compared, to assess possible differences in distribution. Data were also stratified and compared according to clinical severity of preeclampsia. Finally, CRH, PLAC1, and selectin-P were plotted against quantitative distributions of blood pressure and proteinuria. Results All markers were differently distributed between cases and controls. Median values in subgroups correlated with severity of preeclampsia. All markers correlated with both. Selectin-P was identified as the marker with the highest degree of correlation. No correlation was found between any markers in the control group and proteinuria or blood pressure. Conclusion CRH, PLAC1, and selectin-P are distributed differently in preeclampsia cases compared to controls and correlate with signs of preeclampsia. Copyright © 2007 John Wiley & Sons, Ltd. [source] | |||||||||||||