QUANTITATIVE ASSESSMENT OF THE DE NOVO STEROL AND STEROID SYNTHESIS IN THE HUMAN FOETO-PLACENTAL UNIT.

1970 ◽  
Vol 65 (4) ◽  
pp. 663-674 ◽  
Author(s):  
R. S. Mathur ◽  
D. F. Archer ◽  
N. Wiqvist ◽  
E. Diczfalusy
Keyword(s):  
Sodium Acetate ◽  
Quantitative Assessment ◽  
Cholesterol Synthesis ◽  
De Novo ◽  
Internal Standard ◽  
The Other ◽  
Radioactive Material ◽  
Human Foetus ◽  
Steroid Synthesis ◽  
Average Quantity

ABSTRACT In order to assess the quantitative significance of the de novo cholesterol synthesis in the foeto-placental unit at midgestation, two midgestation foetuses and two complete foeto-placental units were perfused with [14C]-sodium acetate immediately following their removal at laparotomy. The perfusions were carried out at 36°C for 120 min administering 3.0 and 6.0 mCi of [14C] sodium acetate, respectively. The amount of [14C]-cholesterol formed was estimated on the basis of the recovery of [7α-3H]-cholesterol internal standard present in the radiochemically homogeneous cholesterol isolated from the various tissues. The cholesterol isolated from the placentas was devoid of any [14C] label. On the other hand, [14C] cholesterol was isolated from all perfusates, as well as from all foetal tissues studied, including the adrenals, livers, testicles, brains and residual foetal tissues. The average quantity of radiochemically homogeneous [14C] cholesterol formed by the four foetuses corresponded to 0.68% of the radioactive material perfused: 0.45% was isolated from the liver, 0.13% from the adrenals, 0.01% from the testicles and 0.08% from the perfusates. Cholesterol sulphate was also isolated from the extracts of adrenals, livers and perfusates. The quantity of [14C] cholesterol sulphate formed was much less than that of [14C] cholesterol; following correction for procedural losses, the total amount of [14C] cholesterol sulphate isolated did not exceed 0.01% of the perfused material. It is concluded that the midgestation human foetus synthesizes large quantities of cholesterol, utilizing small molecular material such as sodium acetate as a precursor and that part of the cholesterol synthesized by the foetus is secreted to the placenta.

QUANTITATIVE ASSESSMENT OF THE DE NOVO STEROL AND STEROID SYNTHESIS IN THE HUMAN FOETO-PLACENTAL UNIT

1971 ◽  
Vol 66 (4) ◽  
pp. 666-678 ◽  
Author(s):  
D. F. Archer ◽  
R. S. Mathur ◽  
N. Wiqvist ◽  
E. Diczfalusy
Keyword(s):  
Sodium Acetate ◽  
Quantitative Assessment ◽  
De Novo ◽  
Isolation Procedure ◽  
Predominant Formation ◽  
Human Foetus ◽  
Steroid Synthesis ◽  
Internal Standards ◽  
Carbon 14 ◽  
Hydroxy Progesterone

ABSTRACT The quantitative significance of the de novo synthesis of Δ5- and Δ4-steroids was assessed in the midgestation human foetus. Two midgestation foetuses and two complete foeto-placental units were perfused at 36°C for 120 minutes with 3.0 and 6.0 mCi of [14C] sodium acetate, respectively, and radiochemically homogeneous carbon-14 labelled steroids were isolated from the adrenals, livers and perfusates. Losses throughout the isolation procedure were monitored in all tissues of all experiments by the recovery of tritium labelled internal standards. In the four experiments, a total of 18.0 mCi of [14C] sodium acetate was perfused and a total of 0.17 μCi of pregnenolone, 2.65 μCi of pregnenolone sulphate, 1.07 μCi of dehydroepiandrosterone and 8.64 μCi of dehydroepiandrosterone sulphate were isolated. A total of 12.53 μCi were isolated in the form of these four compounds; 10.13 μCi of this was present in the perfusates. In all, 0.07% of the administered [14C]-sodium acetate was converted to the four Δ5-steroids studied and 0.048% to dehydroepiandrosterone sulphate. Progesterone was isolated from the perfusates and liver extracts, and 17α-hydroxy-progesterone, androstenedione and testosterone from the perfusates. In the four experiments, a total of 0.045 μCi of carbon-14 labelled Δ4-steroids were isolated, predominantly from the perfusates. In all, less than 0.0003% of the perfused [14C] sodium acetate was converted to Δ4-steroids. Thus, almost 300 times more Δ5- than Δ4-steroids were formed. It is concluded that the extensive de novo steroidogenetic processes taking place in the midgestation human foetus lead to the predominant formation of Δ5-steroid sulphates.

ACETATE AND CHOLESTEROL METABOLISM IN THE HUMAN FOETO-PLACENTAL UNIT AT MIDGESTATION

1970 ◽  
Vol 63 (1) ◽  
pp. 119-133 ◽  
Author(s):  
G. Telegdy ◽  
J. W. Weeks ◽  
D. F. Archer ◽  
N. Wiqvist ◽  
E. Diczfalusy
Keyword(s):  
Sodium Acetate ◽  
De Novo ◽  
Cholesterol Metabolism ◽  
Human Foetus ◽  
Homogeneous Form ◽  
Per Se ◽  
Hydroxy Progesterone

ABSTRACT Two complete foeto-placental units were perfused at midgestation with 5.0 mCi of uniformly labelled 14C-sodium acetate plus 5.0 mCi of cholesterol-7α-3H and two isolated foetuses were perfused with 2.5 mCi of 14C-labelled sodium acetate plus 2.5 mCi of cholesterol-7α-3H. The perfusions were carried out at 35–36°C for 90 min. The foetal adrenals, livers, testes and perfusates were analyzed and various labelled steroids were isolated in a radiochemically homogeneous form. Major quantities of 14C- and 3H-labelled pregnenolone (3β-hydroxy-pregn-5-en-20-one) and dehydroepiandrosterone (3β-hydroxy-androst-5-en-17-one) were isolated from the foetal perfusates, livers and adrenals. Minor amounts of 14C- and 3H-labelled progesterone (pregn-4-ene-3,20-dione) were isolated from the perfusates and adrenals, and 17α-hydroxy-progesterone (17α-hydroxy-pregn-4-ene-3,20-dione) and androstenedione (androst-4-ene-3,17-dione) from the perfusates. Smaller amounts of exclusively 14C-labelled androstenedione were isolated also from the adrenals. No labelled progesterone, androstenedione or testosterone (17β-hydroxy-androst-4-en-3-one) was detected in the testes. Attempts to isolate 20α-dihydroprogesterone (20α-hydroxy-pregn-4-en-3-one) or 20β-dihydroprogesterone (20β-hydroxy-pregn-4-en-3-one) from the perfusates, adrenals and livers failed. No labelled cortisol (11β,17,21-trihydroxy-pregn-4-ene-3,20-dione) or corticosterone (11β,21-dihydroxy-pregn-4-ene-3,20-dione) was detected in the adrenals, and no testosterone, oestrone (3-hydroxy-oestra-1,3,5(10)-trien-17-one) or 16α-hydroxy-dehydroepiandrosterone (3β,16α-dihydroxy-androst-5-en-17-one) in the perfusates. Pregnenolone and dehydroepiandrosterone (which were present in approximately equal amounts) accounted for as much as 95% of all steroids isolated from all sources. The bulk of these two steroids was isolated from the perfusates. The 14C/3H ratio of the pregnenolone and dehydroepiandrosterone isolated from the conjugated fraction of the perfusates was much higher than that of the unconjugated compounds. It is concluded that the midgestation human foetus is capable per se of carrying out the de novo synthesis of major quantities of pregnenolone and dehydroepiandrosterone. It is suggested that in foetal steroidogenesis acetate is utilized predominantly via a conjugated pathway and circulating cholesterol mainly via an unconjugated pathway.

DE NOVO SYNTHESIS OF STEROIDS AND STEROID SULPHATES BY THE TESTICLES OF THE HUMAN FOETUS AT MIDGESTATION

1972 ◽  
Vol 71 (4) ◽  
pp. 792-800 ◽  
Author(s):  
R. S. Mathur ◽  
N. Wiqvist ◽  
E. Diczfalusy
Keyword(s):  
Sodium Acetate ◽  
De Novo ◽  
De Novo Synthesis ◽  
Human Foetus ◽  
Internal Standards ◽  
Human Foetuses

ABSTRACT The de novo synthesis of steroids and steroid sulphates by the testicles of four human foetuses at midgestation was studied. Two foetuses and two foeto-placental units were perfused at 36°C for 120 minutes with 3.0 and 6.0 mCi of [14C] sodium acetate, respectively. Radiochemically homogeneous steroids and steroid sulphates were isolated from the testicular extracts. Tritium labelled internal standards were used in order to assess procedural losses. No labelled steroids were detected in the testicular extracts in one case. From the testicles of each of the three other foetuses pregnenolone, pregnenolone sulphate, dehydroepiandrosterone, dehydroepiandrosterone sulphate, Δ5-androstenediol and testosterone were isolated. Progesterone and androstenedione were isolated in only one case each. Pregnenolone was found to be the predominant steroid formed. It is concluded that the testicles of midgestation human foetuses synthesize and secrete testosterone. It is likely that for the synthesis of this testosterone, the foetal testicles utilize preferentially the so-called Δ5-pathway.

ACETATE AND CHOLESTEROL METABOLISM IN THE HUMAN FOETO-PLACENTAL UNIT AT MIDGESTATION.

1970 ◽  
Vol 63 (1) ◽  
pp. 91-104 ◽  
Author(s):  
G. Telegdy ◽  
J. W. Weeks ◽  
U. Lerner ◽  
G. Stakemann ◽  
E. Diczfalusy
Keyword(s):  
Human Placenta ◽  
Metabolic Pathway ◽  
Sodium Acetate ◽  
Cholesterol Metabolism ◽  
The Other ◽  
Human Foetus ◽  
Homogeneous Form ◽  
Other Hand ◽  
Maternal Side

ABSTRACT As the first part of a series of investigations on acetate and cholesterol metabolism, the conversion of acetate to cholesterol was studied in the various compartments of the midgestation foeto-placental unit in perfusion experiments carried out for 90 min at 35–36°C. Following their removal at laparotomy two complete foeto-placental units were perfused each with 5.0 mCi of uniformly labelled sodium acetate-14C + 5.0 mCi of cholesterol-7α-3H. The study was completed by the separate perfusion of two isolated midgestation foetuses and two midgestation placentas. The doses administered in each of these four last experiments were 2.5 mCi of 14C-labelled acetate and 2.5 mCi of 3H-labelled cholesterol. Cholesterol was isolated in a radiochemically homogeneous form from each of the tissues studied. The cholesterol isolated from the placentas, placental perfusates and from the blood bathing the placenta from the maternal side (»maternal perfusates«) contained exclusively 3H-label. On the other hand, the cholesterol isolated from all foetal livers, adrenals, testicles, 3 of 4 residual foetal tissues and 1 out of 4 foetal perfusates also contained significant quantities of 14C-label. It is concluded, that the midgestation human placenta is not capable of synthesizing cholesterol from acetate, but that the conversion of acetate to cholesterol is a quantitatively significant metabolic pathway in the human foetus at midgestation.

ACETATE AND CHOLESTEROL METABOLISM IN THE HUMAN FOETO-PLACENTAL UNIT AT MIDGESTATION

1970 ◽  
Vol 63 (1) ◽  
pp. 105-118 ◽  
Author(s):  
G. Telegdy ◽  
J. W. Weeks ◽  
N. Wiqvist ◽  
E. Diczfalusy
Keyword(s):  
Human Placenta ◽  
Sodium Acetate ◽  
De Novo ◽  
Cholesterol Metabolism ◽  
Steroid Synthesis ◽  
Homogeneous Form

ABSTRACT Two midgestation placentas were perfused with 2.5 mCi of uniformly labelled 14C-sodium acetate plus 2.5 mCi cholesterol-7α-3H. and two complete foeto-placental units were perfused with 5.0 mCi of 14C-labelled sodium acetate plus 5.0 mCi of cholesterol-7α-3H. The perfusions were carried out at 35–36°C for 90 min. After the perfusion of the isolated placentas, the following 3H-labelled steroids were isolated from the placentas as well as from the perfusates in a radiochemically homogeneous form: pregnenolone (3β-hydroxy-pregn-5-en-20-one), progesterone (pregn-4-ene-3,20-dione), 20α-dihydroprogesterone (20α-hydroxy-pregn-4-en-3-one), 20β-dihydroprogesterone (20β-hydroxy-pregn-4-en-3-one), 17α-hydroxy-pregnenolone (3β,17α-dihydroxy-pregn-5-en-20-one),dehydroepiandrosterone(3β-hydroxy-androst-5-en-17-one) and 17β-oestradiol (oestra-1,3,5(10)-triene-3,17β-diol). The same compounds were also isolated from the placentas following the perfusion of the complete foeto-placental units. With the exception of pregnenolone and progesterone, all steroids were isolated in minute quantities. None of the steroids isolated contained any 14C-label. It is concluded that the midgestation human placenta is not capable of carrying out any de novo steroid synthesis from acetate and that cholesterol is an obligatory precursor in placental steroidogenesis.

DE NOVO SYNTHESIS OF STEROIDS BY THE TESTES OF THE HUMAN FOETUS AT MIDGESTATION

1971 ◽  
Vol 68 (1_Supplb) ◽  
pp. S135 ◽  
Author(s):  
R. S. Mathur ◽  
N. Wiqvist ◽  
E. Diczfalusy
Keyword(s):  
De Novo ◽  
De Novo Synthesis ◽  
Human Foetus

Voronoi Analysis of a Soccer Game

2004 ◽  
Vol 9 (3) ◽  
pp. 233-240 ◽  
Author(s):  
S. Kim
Keyword(s):  
Collective Behavior ◽  
Quantitative Assessment ◽  
The Other ◽  
Analysis Method ◽  
Random System ◽  
Soccer Game ◽  
Voronoi Polygons ◽  
The Mean

This paper describes a Voronoi analysis method to analyze a soccer game. It is important for us to know the quantitative assessment of contribution done by a player or a team in the game as an individual or collective behavior. The mean numbers of vertices are reported to be 5–6, which is a little less than those of a perfect random system. Voronoi polygons areas can be used in evaluating the dominance of a team over the other. By introducing an excess Voronoi area, we can draw some fruitful results to appraise a player or a team rather quantitatively.

Comparison of Postoperative Pain between Laser-Assisted Uvulopalatoplasty, Uvulopalatopharyngoplasty, and Radiofrequency Volumetric Tissue Reduction of the Palate

2000 ◽  
Vol 122 (3) ◽  
pp. 402-409 ◽  
Author(s):  
Robert J. Troell ◽  
Nelson B. Powell ◽  
Robert W. Riley ◽  
Kasey K. Li ◽  
Christian Guilleminault
Keyword(s):  
Quantitative Assessment ◽  
Sleep Disordered Breathing ◽  
The Other ◽  
Narcotic Analgesics ◽  
Pain Medications ◽  
Pain Scales ◽  
Analgesic Medication ◽  
The Mean ◽  
Radiofrequency Volumetric Tissue Reduction ◽  
Tissue Reduction

OBJECTIVES: This study compares the posttreatment discomfort between laser-assisted uvulopalatoplasty (LAUP), uvulopalatopharyngoplasty (UPPP), and radiofrequency volumetric tissue reduction (RFVTR) of the palate through the use of visual analog pain scales and a quantitative assessment of the analgesic medication taken. METHODS: In one group, LAUP (n = 10) or UPPP (n = 9) was used to treat patients' snoring or sleep-disordered breathing (SDB), and the other group underwent RFVTR (n = 22). RESULTS: The mean numbers of days with pain after RFVTR, LAUP, and UPPP were 2.6, 13.8, and 14.3 days, respectively. Narcotic analgesics were required in the RFVTR, LAUP and UPPP groups in 9%, 100%, and 100% of the subjects, respectively. The mean number of these days requiring narcotic pain medications for RFVTR, LAUP, and UPPP was 0.2, 11.8, and 12.4 days, whereas the total narcotic equivalent was 0.3, 7.4 and 29.6 days, respectively. CONCLUSION: RFVTR of the soft palate produced less posttreatment pain than LAUP or UPPP. LAUP and UPPP appeared to show little difference in the severity or duration of posttreatment discomfort.

Abiotic Reactivity of De Novo Designed Artificial Copper Peptides (ArCuPs): The Case of C-H Activation

2022 ◽  
Author(s):  
Divyansh Prakash ◽  
Suchitra Mitra ◽  
Morgan Murphy ◽  
Saumen Chakraborty
Keyword(s):  
Steric Effect ◽  
De Novo ◽  
Outer Sphere ◽  
The Other ◽  
Easy Access ◽  
Oxygen Species ◽  
Redox Potentials ◽  
Spectroscopic Feature ◽  
Detailed Assessment ◽  
Active Variant

We report a series of de novo designed Artificial Cu Peptides (ArCuPs) that oxidize and peroxygenate C-H bonds of model abiotic substrates via electrochemically generated Cu-oxygen species using H2O2 as the terminal oxidant, akin to native Cu enzymes. Detailed assessment of kinetic parameters established the catalytic nature of the ArCuPs. Selective alteration of outer sphere steric at the d layers above and below the Cu site allows facilitated access of substrates, where a more pronounced effect on catalysis is observed when space is created at the d layer below the Cu site via Ile to Ala mutation producing a kcat of 6.2 s-1, TONmax of 14800 and catalytic proficiency (kcat/KM/kuncat) of 340 M-1 for the oxidation of benzyl alcohol. Independent spectroscopic studied revealed that the rate of formation of the Cu-oxygen species and the spectroscopic feature of the most active variant is distinct compared to the other ArCuPs. Systematic alteration of outer sphere hydrophobicity led to a correlated tuning of the T2 Cu site redox potentials by ~80 mV. The enhanced activity of the ArCuP variant is attributed to a combination of steric effect that allows easy access of substrates, the nature of Cu-oxygen species, and stability of this construct compared to others, where Ile to Ala mutation unexpectedly leads to a higher thermostability which is further augmented by Cu binding.

Paranemin and the organization of desmin filament networks

2001 ◽  
Vol 114 (6) ◽  
pp. 1079-1089 ◽  
Author(s):  
S.C. Schweitzer ◽  
M.W. Klymkowsky ◽  
R.M. Bellin ◽  
R.M. Robson ◽  
Y. Capetanaki ◽  
...  
Keyword(s):  
Cell Lines ◽  
Intermediate Filament ◽  
Transgene Expression ◽  
De Novo ◽  
Muscle Cells ◽  
The Other ◽  
Intermediate Filament Proteins ◽  
Mouse Fibroblasts ◽  
Filament Networks ◽  
Filament Network

De novo expression of vimentin, GFAP or peripherin leads to the assembly of an extended intermediate filament network in intermediate filament-free SW13/cl.2 cells. Desmin, in contrast, does not form extended filament networks in either SW13/cl.2 or intermediate filament-free mouse fibroblasts. Rather, desmin formed short thickened filamentous structures and prominent spot-like cytoplasmic aggregates that were composed of densely packed 9–11 nm diameter filaments. Analysis of stably transfected cell lines indicates that the inability of desmin to form extended networks is not due to a difference in the level of transgene expression. Nestin, paranemin and synemin are large intermediate filament proteins that coassemble with desmin in muscle cells. Although each of these large intermediate filament proteins colocalized with desmin when coexpressed in SW-13 cells, expression of paranemin, but not synemin or nestin, led to the formation of an extended desmin network. A similar rescue of desmin network organization was observed when desmin was coexpressed with vimentin, which coassembles with desmin, or with keratins, which formed a distinct filament network. These studies demonstrate that desmin filaments differ in their organizational properties from the other vimentin-like intermediate filament proteins and appear to depend upon coassembly with paranemin, at least when they are expressed in non-muscle cells, in order to form an extended filament network.

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