Collagen in the fetal membranes of sheep: changes throughout gestation and effects of dexamethasone at 60 days

1997 ◽  
Vol 9 (4) ◽  
pp. 455 ◽  
Author(s):  
Lynne Shandley ◽  
Karen M. Moritz ◽  
Chrishan S. Samuel ◽  
E. Marelyn Wintour
Keyword(s):  
Gel Electrophoresis ◽  
Normal Development ◽  
Allantoic Fluid ◽  
Dry Weight ◽  
Collagen Content ◽  
Fetal Membranes ◽  
Dexamethasone Treatment ◽  
Collagen Types ◽  
Volume Changes ◽  
Volume Increase

The tensile strength of fetal membranes is largely due to their collagen content. In this study we have examined the changes in collagen in the amniotic and allantoic membranes of the sheep over a wide gestational range (27–142 days of gestation; term, 145–150 days). The results have been correlated with volume changes in normal development, and in particular, the changes in allantois have been studied after a rapid and extensive increase in allantoic volume, as a result of maternal dexamethasone treatment (0·76 mg h-1 for 48 h) from Day 60 of gestation. Electron microscopy and immunohistochemistry were used to delineate collagen distribution, and gel electrophoresis was used to assess the relative proportions of each type. In the amnion, collagen content increased from 37±4% to 50±1% dry weight of the tissue from 41–102 days and declined slightly thereafter. In the allantois, collagen content increased from 20±1% at Day 27 to 50±6% at Day 142, significantly correlated with a volume increase from 253 mL to 813±274 mL. Collagen types I (>85%), III (10%) and small amounts of types IV and V (<5%) were identified in both membranes at all ages. When allantoic fluid volume was increased rapidly by maternal dexamethasone infusion, there was a significant decrease in collagen content from 38±6% to 25±2% (P < 0·05). By immunohistochemistry it was observed that both epithelial cells and fibroblasts were synthesizing collagen.

Is the Collagen Content Reduced when the Fetal Membranes Rupture?

1987 ◽  
Vol 24 (2) ◽  
pp. 92-94 ◽  
Author(s):  
George R. Evaldson ◽  
Bertil Larsson ◽  
Hans Jiborn
Keyword(s):  
Collagen Content ◽  
Fetal Membranes

scholarly journals Pressure- and Temperature-Induced Insertion of N2, O2 and CH4 to Ag-Natrolite

Materials ◽  
2020 ◽  
Vol 13 (18) ◽  
pp. 4096
Author(s):  
Donghoon Seoung ◽  
Hyeonsu Kim ◽  
Pyosang Kim ◽  
Yongmoon Lee
Keyword(s):  
Unit Cell Volume ◽  
Molecular Size ◽  
Unit Cell ◽  
Volume Changes ◽  
Volume Increase ◽  
X Ray ◽  
Onset Pressure ◽  
Two Stages ◽  
Cell Volumes

This paper aimed to investigate the structural and chemical changes of Ag-natrolite (Ag16Al16Si24O80·16H2O, Ag-NAT) in the presence of different pressure transmitting mediums (PTMs), such as N2, O2 and CH4, up to ~8 GPa and 250 °C using in situ synchrotron X-ray powder diffraction and Rietveld refinement. Pressure-induced insertion occurs in two stages in the case of N2 and O2 runs, as opposed to the CH4 run. First changes of the unit cell volume in N2, O2 and CH4 runs are observed at 0.88(5) GPa, 1.05(5) GPa and 1.84(5) GPa with increase of 5.7(1)%, 5.5(1)% and 5.7(1)%, respectively. Subsequent volume changes of Ag-natrolite in the presence of N2 and O2 appear at 2.15(5) GPa and 5.24(5) GPa with a volume increase of 0.8(1)% and a decrease of 3.0(1)%, respectively. The bulk moduli of the Ag-NAT change from 42(1) to 49(7), from 38(1) to 227(1) and from 49(3) to 79(2) in the case of N2, O2 and CH4 runs, respectively, revealing that the Ag-NAT becomes more incompressible after each insertion of PTM molecules. The shape of the channel window of the Ag-NAT changes from elliptical to more circular after the uptake of N2, O2 and CH4. Overall, the experimental results of Ag-NAT from our previous data and this work establish that the onset pressure exponentially increases with the molecular size. The unit cell volumes of the expanded (or contracted) phases of the Ag-NAT have a linear relationship and limit to maximally expand and contract upon pressure-induced insertion.

scholarly journals Solvent Stress Response of the Denitrifying Bacterium “Aromatoleum aromaticum” Strain EbN1

2008 ◽  
Vol 74 (8) ◽  
pp. 2267-2274 ◽  
Author(s):  
Kathleen Trautwein ◽  
Simon Kühner ◽  
Lars Wöhlbrand ◽  
Thomas Halder ◽  
Kenny Kuchta ◽  
...  
Keyword(s):  
Stress Responses ◽  
Aromatic Compounds ◽  
Gel Electrophoresis ◽  
Physiological Responses ◽  
Dry Weight ◽  
Anaerobic Growth ◽  
Solvent Concentration ◽  
Denitrifying Bacterium ◽  
Aromatic Substrates ◽  
Difference Gel Electrophoresis

ABSTRACT The denitrifying betaproteobacterium “Aromatoleum aromaticum” strain EbN1 degrades several aromatic compounds, including ethylbenzene, toluene, p-cresol, and phenol, under anoxic conditions. The hydrophobicity of these aromatic solvents determines their toxic properties. Here, we investigated the response of strain EbN1 to aromatic substrates at semi-inhibitory (about 50% growth inhibition) concentrations under two different conditions: first, during anaerobic growth with ethylbenzene (0.32 mM) or toluene (0.74 mM); and second, when anaerobic succinate-utilizing cultures were shocked with ethylbenzene (0.5 mM), toluene (1.2 mM), p-cresol (3.0 mM), and phenol (6.5 mM) as single stressors or as a mixture (total solvent concentration, 2.7 mM). Under all tested conditions impaired growth was paralleled by decelerated nitrate-nitrite consumption. Additionally, alkylbenzene-utilizing cultures accumulated poly(3-hydroxybutyrate) (PHB) up to 10% of the cell dry weight. These physiological responses were also reflected on the proteomic level (as determined by two-dimensional difference gel electrophoresis), e.g., up-regulation of PHB granule-associated phasins, cytochrome cd1 nitrite reductase of denitrification, and several proteins involved in oxidative (e.g., SodB) and general (e.g., ClpB) stress responses.

Agonist-induced cytoplasmic volume changes in cultured rabbit parietal cells

2000 ◽  
Vol 279 (1) ◽  
pp. G40-G48 ◽  
Author(s):  
Thorsten Sonnentag ◽  
Wolf-Kristian Siegel ◽  
Oliver Bachmann ◽  
Heidi Rossmann ◽  
Andreas Mack ◽  
...  
Keyword(s):  
Volume Regulation ◽  
Parietal Cells ◽  
Cell Swelling ◽  
Secretory Process ◽  
Cell Shrinkage ◽  
Rapid Loss ◽  
Volume Changes ◽  
Volume Increase ◽  
Regulatory Volume Increase ◽  
Stimulation Of

Concomitant Na+/H+ and Cl−/HCO3 − exchange activation occurs during stimulation of acid secretion in cultured rabbit parietal cells, possibly related to a necessity for volume regulation during the secretory process. We investigated whether cytoplasmic volume changes occur during secretagogue stimulation of cultured rabbit parietal cells. Cells were loaded with the fluorescent dye calcein, and the calcein concentration within a defined cytoplasmic volume was recorded by confocal microscopy. Forskolin at 10−5 M, carbachol at 10−4 M, and hyperosmolarity (400 mosmol) resulted in a rapid increase in the cytoplasmic dye concentration by 21 ± 6, 9 ± 4, and 23 ± 5%, respectively, indicative of cell shrinkage, followed by recovery to baseline within several minutes, indicative of regulatory volume increase (RVI). Depolarization by 5 mM barium resulted in a decrease of the cytoplasmic dye concentration by 10 ± 2%, indicative of cell swelling, with recovery within 15 min, and completely prevented forskolin- or carbachol-induced cytoplasmic shrinkage. Na+/H+ exchange inhibitors slightly reduced the initial cell shrinkage and significantly slowed the RVI, whereas 100 μM bumetanide had no significant effect on either parameter. We conclude that acid secretagoguges induce a rapid loss of parietal cell cytoplasmic volume, followed by RVI, which is predominantly mediated by Na+/H+ and Cl−/HCO3 − exchange.

scholarly journals Heterogeneity of uidA gene in environmental Escherichia coli populations

2005 ◽  
Vol 3 (3) ◽  
pp. 297-304 ◽  
Author(s):  
Clarivel Lasalde ◽  
Roberto Rodriguez ◽  
Gary A. Toranzos ◽  
Henry H. Smith
Keyword(s):  
Escherichia Coli ◽  
Genetic Heterogeneity ◽  
Gel Electrophoresis ◽  
Denaturing Gradient Gel Electrophoresis ◽  
Dry Weight ◽  
Source Tracking ◽  
Tropical Rain Forests ◽  
Rain Forests ◽  
E Coli ◽  
Gradient Gel Electrophoresis

Previous studies have shown that Escherichia coli can be isolated from non-polluted rivers and from bromeliad axilae in pristine areas of tropical rain forests. Finding E. coli in pristine environments is unusual because this bacterium is thought to only survive in the gut of warm-blooded animals and thus its presence should indicate recent fecal contamination. The aims of this study were 1) to determine if E. coli is part of the native soil microbiota in tropical rain forests and 2) to determine if genetic heterogeneity exists among E. coli populations. High concentrations of total coliforms (104–105 cells per 10 g of soil dry weight) and low concentrations of thermotolerant coliforms (101–102 cells per 10 g dry soil, the majority of these were found to be E. coli) were detected. PCR using uidA-specific primers was done on DNA purified from E. coli isolates and the resulting amplicons analysed by denaturing-gradient gel electrophoresis (DGGE). Out of several hundred isolates, mixtures of nine different amplicons were consistently observed. The different patterns of DGGE observed indicate that the E. coli populations in these pristine soils are genetically heterogeneous. Fecal and environmental E. coli isolates were also analysed by pulsed-field gel electrophoresis (PFGE) which showed high DNA sequence variation among the E. coli isolates. Because of these differences in the genomes, PFGE did not allow grouping of environmental versus human isolates of E. coli when compared side to side. The apparent genetic polymorphisms, as a result of genetic heterogeneity, observed in isolates from the same pristine site indicate that source tracking may be difficult to carry out using E. coli as the target organism.

Plantigrade settlement of the musselMytilus coruscusin response to natural biofilms on different surfaces

2014 ◽  
Vol 94 (8) ◽  
pp. 1639-1649 ◽  
Author(s):  
Jin-Long Yang ◽  
Xuan Zhou ◽  
Yi-Feng Li ◽  
Xing-Pan Guo ◽  
Xiao Liang ◽  
...  
Keyword(s):  
Surface Properties ◽  
Gel Electrophoresis ◽  
Denaturing Gradient Gel Electrophoresis ◽  
Dry Weight ◽  
High Variability ◽  
Short Term ◽  
Gradient Gel Electrophoresis ◽  
Diatom Density ◽  
Insight Into ◽  
Natural Biofilms

Surface properties affect the attachment of micro- and macroscopic marine organisms. The current study examined the settlement response of the musselMytilus coruscusplantigrades to natural biofilms formed on surfaces of different wettability. The percentages of plantigrade settlement were not influenced by the biofilms formed on variously wettable surfaces in the short term, but after 10 days, the plantigrade settlement rates decreased on biofilms formed on lower wettability surfaces. In general, lower wettability of the surfaces resulted in the decrease of the dry weight, bacterial and diatom density and the thickness of natural biofilms when compared to high wettability surfaces. In contrast, chlorophyll-aconcentration in biofilms was independent of the initial wettability of the surfaces. Comparative cluster analysis of bacterial denaturing gradient gel electrophoresis patterns revealed that high variability existed between the bacterial community on high wettability surfaces and that on low wettability surfaces. Thus, surface wettability affects the formation of natural biofilms, and this variation in biofilms developed on different wettability surfaces may explain the discrepancy in their corresponding inducing activities onM. coruscusplantigrade settlement. This finding provides new insight into interactions between mussel settlement, biofilm characteristics and surface properties.

Effect of maternal glucocorticoid treatment on ovine fetal fluids at 0.6 gestation

1995 ◽  
Vol 7 (6) ◽  
pp. 1595 ◽  
Author(s):  
K Tangalakis ◽  
K Moritz ◽  
L Shandley ◽  
EM Wintour
Keyword(s):  
Prolonged Exposure ◽  
Allantoic Fluid ◽  
Urine Flow ◽  
Dexamethasone Treatment ◽  
Glucocorticoid Treatment ◽  
51Cr Edta ◽  
Group 3 ◽  
Ovine Fetal ◽  
Bovine Type ◽  
Fetal Fluids

This study examined the effects of maternal dexamethasone treatment on the volume and composition of fetal fluids, and on placental morphology at 0.6 gestation (80-90 days). Nine pregnant ewes were infused with dexamethasone (D, 0.76 mg h-1 for 72 h) while an additional nine ewes received saline (S, 0.38 mL h-1 for 72 h). Allantoic fluid (ALF) volume was significantly greater (P < 0.01) in the D group (737 +/- 116 mL) than in the S group (190 +/- 55 mL), but there was no difference in amniotic fluid (AMF) volume. The urine flow rate was 11 times higher in three D fetuses. The 51Cr-EDTA infused into the bladders of four fetuses during the final 4-5 h of the 72 infusions was detected in both AMF and ALF. Dexamethasone treatment significantly altered the composition of the fetal fluids but had no affect on fetal body weight, organ weights and placental weight; however, there were fewer cotyledons under 5 g (P < 0.05). In the D group, 3% of cotyledons were of the 'bovine' type in morphology, whereas all cotyledons in the S group were of the 'ovine' type. These findings suggest that prolonged exposure to large doses of glucocorticoids during pregnancy would affect the volume and composition of the fetal fluids and placental morphology, with potentially detrimental effects on the fetus.

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