TRANSFORMATION OF CORTICOSTERONE IN THE FOETAL AND PLACENTAL COMPARTMENTS OF THE RAT

1972 ◽  
Vol 69 (4) ◽  
pp. 689-700 ◽  
Author(s):  
S. Roy ◽  
J. R. Pasqualini
Keyword(s):  
Quantitative Evaluation ◽  
Liver Tissue ◽  
Subcellular Fractions ◽  
Pure Form ◽  
Radioactive Material ◽  
Corticosterone Metabolites ◽  
Liver Tissues

ABSTRACT 3H-Corticosterone was administered subcutaneously in vivo and in situ to 32 rat foetuses at 16–18 days of gestation. 30 min after the injection, 11% of the administered dose was localized in the liver tissue, 5% in the lungs, 3% in the intestines and 5% in the placenta. The foetal tissues were separated into different subcellular fractions: I) nucleo-fibrillar, II) mitochondrial-microsomal, and III) cytosol. It was observed that corticosterone was extensively metabolized in all three of these subcellular fractions. The following metabolites were identified in a radiochemically pure form: 11-dehydrocorticosterone, 5α-dihydrocorticosterone, tetrahydrocorticosterone, 5α-tetrahydrocorticosterone. Quantitative evaluation of the corticosterone metabolites showed that the greatest part of these steroids consisted of dihydro- and tetrahydrocorticosterone derivatives, principally with a 5α configuration. In the liver tissues, 0.5 % of the radioactive material was found in a conjugated form, mainly as ester sulphates. The radioactive material liberated after solvolysis of these conjugates was tentatively identified as corticosterone, 5α-dihydrocorticosterone and 5α-tetrahydrocorticosterone.

Characteristics of Phytochrome in Glutaraldehyde-Treated Maize Coleoptiles

1975 ◽  
Vol 2 (3) ◽  
pp. 281 ◽  
Author(s):  
R Yu
Keyword(s):  
Soluble Fraction ◽  
Red Light ◽  
Intracellular Distribution ◽  
Subcellular Fractions ◽  
Particulate Fraction ◽  
Cell Fractionation

Glutaraldehyde treatment was used to stabilize the in situ distribution of phytochrome at intervals during the course of phytochrome dark reactions. Total cellular phytochrome decreased in maize coleoptiles when they were returned to darkness and incubated after red irradiation. Photoreversibility was lost in both the soluble and particulate fractions, being faster in the particulate fraction. Glutaraldehyde treatment of coleoptiles immediately after irradiation inhibited loss of particulate phytochrome in the dark. When coleoptiles were irradiated with R/FR, i.e, red light (R, 660 nm) followed by far-red light (FR, 737 nm), and then incubated in the dark, the loss of particulate phytochrome was compensated for by an increase of phytochrome in the soluble fraction, resulting in negligible loss of total phytochrome. The phytochrome dark reactions in subcellular fractions of coleoptiles irradiated in vivo with R and R/FR and extracted in Mg2+-containing buffer were similar to those in corresponding subcellular fractions of coleoptiles treated with glutaraldehyde before cell fractionation. If the pattern of phytochrome dark reactions in subcellular fractions of R- and R/FR-irradiated coleoptiles treated with glutaraldehyde before cell fractionation truly reffects the in situ situation, this similarity suggests that the phytochrome distribution in subcellular fractions obtained by extraction in Mg2+-containing buffer of coleoptiles irradiated in vivo (without ghtaraldehyde treatment) also represents the intracellular distribution. This conclusion however cannot be extended to the distribution obtained following irradiation of Mg2+-containing non-cellular extracts.

PLACENTAL TRANSFER OF 3H-OESTRIOL-3-SULPHATE-16-GLUCOSIDURONATE AND 3H-OESTRIOL-16-GLUCOSIDURONATE-14C

1972 ◽  
Vol 70 (1) ◽  
pp. 132-142 ◽  
Author(s):  
U. Goebelsmann ◽  
J. M. Roberts ◽  
R. B. Jaffe
Keyword(s):  
Placental Transfer ◽  
Conclusive Evidence ◽  
Radioactive Material ◽  
Maternal Urine ◽  
Urine Specimens

ABSTRACT Four human placentas were perfused in situ at midpregnancy, two with biosynthetically prepared 3H-oestriol-16-glucosiduronate-14C (OE3-16Gl) and two with 3H-oestriol-3-sulphate-16-glucosiduronate (OE3-3S,16Gl). The radioactive material recovered from the placentas, perfusates and maternal urine was quantitated and identified. Only 0.8 to 3.7% of the labelled material administered was recovered from urine specimens; the bulk of the labelled material perfused was found in the extracts of placentas and perfusates. The double-labelled material isolated from the three sources following perfusion with 3H-OE3-16Gl-14C was identified as OE3-16Gl. The 3H/14C ratios measured in these fractions were virtually identical with those of the tracers perfused. Following perfusion with 3H-OE3-3S,16Gl, three-fourths of the 3H-labelled material recovered from the urine was identified as OE3-3S,16Gl and a small but significant portion of the tritiated material extracted from the placentas and perfusates was shown to be 3H-OE3-16Gl. No significant quantities of unconjugated labelled material could be detected in any of the four placental perfusions. The data presented provide conclusive evidence that both OE3-16Gl and OE3-3S,16Gl are transferred across the placenta in situ without previous hydrolysis. The placenta in vivo is capable of converting some OE3-3S,16Gl to OE3-16Gl. The latter conjugate remains unhydrolysed.

scholarly journals Osteogenesis Capability and Degradation Property Evaluation of Injectable Biomaterials: Comparison of Computed Tomography and Ultrasound

2013 ◽  
Vol 2013 ◽  
pp. 1-8
Author(s):  
Yan Chen ◽  
Yuting Yan ◽  
Xiaoming Li ◽  
He Li ◽  
Yue Yuan ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Quantitative Evaluation ◽  
Ultrasound Images ◽  
Noninvasive Technique ◽  
In Situ Forming ◽  
Property Evaluation ◽  
Analysis Technique ◽  
Defect Repair

Injectable biomaterials, which can be physically inserted into a target site without the use of surgery, have received increasing attention in tissue engineering during the last decade. There is also a growing need for quantitative evaluation of the injectable biomaterial directly and noninvasively. The objectives of this study are to originate a quantitative noninvasive technique for evaluation of in situ forming bone biomaterials and to validate the feasibility of diagnostic ultrasound images analysis technique. The potential of ultrasound for quantitative evaluation of tissue development was compared with computed tomography (CT)in vivo. A strong correlation was witnessed between ultrasound gray-scale values (GV) and volumetric mean of CT value (HUm) (r=0.95). Meanwhile, the volume of the material area could be estimated by ultrasound maximum cross-section pixel, which demonstrates a certain consistency with CT mask volume in 3D reconstruction images (r=0.87). In conclusion, ultrasound imaging, which is corresponding with the traditional CT, can be used to evaluate osteogenesis capability and degradation property of injectable biomaterials. It may be a noninvasive, nonradioactive, and effective aid to monitor ossification and reconstruction of biomaterials at the implant region for bone defect repair.

scholarly journals Liver tissue metabolically transformed by alcohol induces immune recognition of liver self-proteins but not in vivo inflammation

2018 ◽  
Vol 314 (3) ◽  
pp. G418-G430
Author(s):  
Michael J. Duryee ◽  
Benjamin M. Wiese ◽  
Jordan R. Bowman ◽  
Jared D. Vanlandingham ◽  
Lynell W. Klassen ◽  
...  
Keyword(s):  
T Cells ◽  
Liver Damage ◽  
Liver Tissue ◽  
Transfer Model ◽  
Immune Recognition ◽  
Liver Slices ◽  
In Vivo Inflammation

Precision-cut liver slices (PCLSs) provide a novel model for studies of alcoholic liver disease (ALD). This is relevant, as in vivo ethanol exposure does not appear to generate significant liver damage in ethanol-fed mice, except in the National Institute on Alcohol Abuse and Alcoholism binge model of ALD. Previous studies have shown that the two metabolites of ethanol consumption, malondialdhyde (MDA) and acetaldehyde (AA), combine to form MDA-AA (MAA) adducts, which have been correlated with the development and progression of ALD. In this study, murine PCLSs were incubated with ethanol and examined for the production of MAA adducts. PCLSs were homogenized, and homogenates were injected into C57BL/6 mice. PCLSs from control-, pair-, and ethanol-fed animals served as targets in in situ cytotoxic assays using primed T cells from mice hyperimmunized with control or ethanol-exposed PCLS homogenates. A CD45.1/CD45.2 passive-transfer model was used to determine whether T cells from the spleens of mice hyperimmunized with PCLS ethanol-exposed homogenates trafficked to the liver. PCLSs incubated with ethanol generated MAA-modified proteins in situ. Cytotoxic (CD8+) T cells from immunized mice killed naïve PCLSs from control- and pair-fed mice in vitro, a response that was blunted in PCLSs from ethanol-fed mice. Furthermore, CD45.1 CD8+ T cells from hyperimmunized mice trafficked to the liver but did not initiate liver damage. This study demonstrates that exposure to liver tissue damaged by ethanol mediates robust immune responses to well-characterized alcohol metabolites and native liver proteins in vitro. Moreover, although these proinflammatory T cells traffic to the liver, these responses appear to be dampened in vivo by locally acting pathways. NEW & NOTEWORTHY This study shows that the metabolites of ethanol and lipid breakdown produce malondialdehyde-acetaldehyde adducts in the precision-cut liver slice model system. Additionally, precision-cut liver slices exposed to ethanol and harboring malondialdehyde-acetaldehyde adducts generate liver-specific antibody and T cell responses in the spleens of naïve mice that could traffic to the liver.

scholarly journals Mass spectrometry imaging of the in situ drug release from nanocarriers

2018 ◽  
Vol 4 (10) ◽  
pp. eaat9039 ◽  
Author(s):  
Jinjuan Xue ◽  
Huihui Liu ◽  
Suming Chen ◽  
Caiqiao Xiong ◽  
Lingpeng Zhan ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Drug Delivery ◽  
Drug Release ◽  
Drug Carrier ◽  
Ionization Mass ◽  
Label Free ◽  
Normal Tissues ◽  
Liver Tissues

It is crucial but of a great challenge to study in vivo and in situ drug release of nanocarriers when developing a nanomaterial-based drug delivery platform. We developed a new label-free laser desorption/ionization mass spectrometry (MS) imaging strategy that enabled visualization and quantification of the in situ drug release in tissues by monitoring intrinsic MS signal intensity ratio of loaded drug over the nanocarriers. The proof of concept was demonstrated by investigating the doxorubicin (DOX)/polyethylene glycol–MoS2 nanosheets drug delivery system in tumor mouse models. The results revealed a tissue-dependent release behavior of DOX during circulation with the highest dissociation in tumor and lowest dissociation in liver tissues. The drug-loaded MoS2 nanocarriers are predominantly distributed in lung, spleen, and liver tissues, whereas the accumulation in the tumor was unexpectedly lower than in normal tissues. This new strategy could also be extended to other drug-carrier systems, such as carbon nanotubes and black phosphorus nanosheets, and opened a new path to evaluate the drug release of nanocarriers in the suborgan level.

In vitro and in vivo polysaccharides assembly: ultrastructural and cytochemical study of growing plant cell wall components.

1978 ◽  
Vol 36 (2) ◽  
pp. 434-435
Author(s):  
D. Reis ◽  
B. Vian ◽  
J. C. Roland
Keyword(s):  
Cell Wall ◽  
Self Assembly ◽  
Plant Cell Wall ◽  
Higher Plants ◽  
Three Dimensional ◽  
Cytochemical Study ◽  
Wall Components

Wall morphogenesis in higher plants is a problem still open to controversy. Until now the possibility of a transmembrane control and the involvement of microtubules were mostly envisaged. Self-assembly processes have been observed in the case of walls of Chlamydomonas and bacteria. Spontaneous gelling interactions between xanthan and galactomannan from Ceratonia have been analyzed very recently. The present work provides indications that some processes of spontaneous aggregation could occur in higher plants during the formation and expansion of cell wall.Observations were performed on hypocotyl of mung bean (Phaseolus aureus) for which growth characteristics and wall composition have been previously defined.In situ, the walls of actively growing cells (primary walls) show an ordered three-dimensional organization (fig. 1). The wall is typically polylamellate with multifibrillar layers alternately transverse and longitudinal. Between these layers intermediate strata exist in which the orientation of microfibrils progressively rotates. Thus a progressive change in the morphogenetic activity occurs.

Three-Dimensional Subcellular Organization of Hepatocytes in Intact Liver: Simultaneous Visualization of Cytoskeletal and Membrane Markers by Confocal Microscopy

1996 ◽  
Vol 54 ◽  
pp. 288-289
Author(s):  
Greg V. Martin ◽  
Ann L. Hubbard
Keyword(s):  
Three Dimensional ◽  
Integral Membrane Proteins ◽  
Polarized Secretion ◽  
Microscope Images ◽  
Computer Aided ◽  
Intracellular Organelles ◽  
Cytoskeletal Elements ◽  
Simultaneous Visualization

The microtubule (MT) cytoskeleton is necessary for many of the polarized functions of hepatocytes. Among the functions dependent on the MT-based cytoskeleton are polarized secretion of proteins, delivery of endocytosed material to lysosomes, and transcytosis of integral plasma membrane (PM) proteins. Although microtubules have been shown to be crucial to the establishment and maintenance of functional and structural polarization in the hepatocyte, little is known about the architecture of the hepatocyte MT cytoskeleton in vivo, particularly with regard to its relationship to PM domains and membranous organelles. Using an in situ extraction technique that preserves both microtubules and cellular membranes, we have developed a protocol for immunofluorescent co-localization of cytoskeletal elements and integral membrane proteins within 20 µm cryosections of fixed rat liver. Computer-aided 3D reconstruction of multi-spectral confocal microscope images was used to visualize the spatial relationships among the MT cytoskeleton, PM domains and intracellular organelles.

Studies on Metabolism of Urokinase and Mechanism of Thrombolysis by Urokinase

1979 ◽  
Vol 42 (03) ◽  
pp. 885-894 ◽  
Author(s):  
Tatsuo Ueno ◽  
Norio Kobayashi ◽  
Tadashi Maekawa
Keyword(s):  
Molecular Weight ◽  
Plasma Clearance ◽  
Radioactive Material ◽  
Optimal Dosage ◽  
Plasma Clot ◽  
Optimal Dosage Regimen ◽  
Arterial Thrombus ◽  
Contact Experiment

SummaryPharmacokinetics of intravenously injected 125I-labeled urokinase (125I-UK) of a molecular weight of 33,000 daltons in normal rabbits and patients with various diseases were investigated. The plasma clearance of 125I-UK in rabbits was described by a biexponential curve within six hours with a half-life of 8 minutes, 2.3 hours, respectively. The radioactivity in the liver and kidneys 15 minutes after iv injection with 125I-UK was 9.6% and 14.0% of the radioactivity injected, respectively. Approximately 80% of the total radioactive material injected was excreted in the urine in 18 hours. No increase in activator activity in the urine was observed after a large amount of UK injection. Activity uptake of 125I-UK by experimentally induced arterial thrombus was little. Lysis of the stasis thrombus was produced by injecting 7.5 × 104 IU of UK in only one out of 8 rabbits. In vitro contact experiment revealed that transfer of 125I-UK to plasma clot is slow (24 hours for 10% of 125I-UK by plasma clot). In 4 patients plasma clearance of 125I-UK was essentially similar to that in rabbits. From the results obtained optimal dosage regimen of UK administration for complete thrombolysis in vivo was discussed.

STUDIES ON THE AROMATISATION OF NEUTRAL STEROIDS IN PREGNANT WOMEN

1964 ◽  
Vol 45 (4) ◽  
pp. 535-559 ◽  
Author(s):  
E. Bolté ◽  
S. Mancuso ◽  
G. Eriksson ◽  
N. Wiqvist ◽  
E. Diczfalusy
Keyword(s):  
Pregnant Women ◽  
Comparative Studies ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Radioactive Material ◽  
Placental Barrier ◽  
Therapeutic Abortion ◽  
Limited Ability ◽  
Better Than

ABSTRACT In 15 cases of therapeutic abortion by laparotomy the placenta was disconnected from the foetus and perfused in situ with tracer amounts of radioactive dehydroepiandrosterone (DHA), dehydroepiandrosterone sulphate (DHAS), androst-4-ene-3,17-dione (A), testosterone (T) and 17β-oestradiol (OE2). Analysis of the placentas, perfusates and urine samples revealed an extensive aromatisation of DHA, A and T; more than 70% of the radioactive material recovered was phenolic, and at least 80 % of this phenolic material was identified as oestrone (OE1), 17β-oestradiol (OE2) and oestriol (OE3), the latter being detected only in the urine. Comparative studies indicated that A and T were aromatised somewhat better than DHA and that all three unconjugated steroids were aromatised to a much greater extent than DHAS. Radioactive OE1 and OE2 were isolated and identified in the placentas and perfusates, but no OE3, epimeric oestriols, or ring D ketols could be detected in these sources, not even when human chorionic gonadotrophin (HCG) was added to the blood prior to perfusion. Lack of placental 16-hydroxylation was also apparent when OE2 was perfused. Regardless of the precursor perfused, there was three times more OE2 than OE1 in the placenta and three times more OE1 than OE2 in the perfusate. This was also the case following perfusion with OE2. The results are interpreted as suggesting the existence in the pregnant human of a placental »barrier« limiting the passage of circulating androgen. The barrier consists of a) limited ability to transfer directly DHAS and b) an enzymic mechanism resulting in the rapid and extensive aromatisation of the important androgens DHA, A and T.

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