Studies of the Metabolism of Asialotransferrins: Relationship Between the Carbohydrate Composition of Bovine, Canine, and Porcine Asialotransferrins and their Metabolic Behavior in the Rabbit

1974 ◽  
Vol 52 (10) ◽  
pp. 845-853 ◽  
Author(s):  
M. W. C. Hatton ◽  
E. Regoeczi ◽  
K.-L. Wong
Keyword(s):  
Negative Charge ◽  
Transfer Rates ◽  
Dual Isotope ◽  
Isotope Tracer ◽  
Native Proteins ◽  
Terminal Galactose ◽  
The Difference ◽  
Metabolic Behavior ◽  
Galactosyl Residues

The catabolism and distribution of bovine, canine, and porcine asialotransferrins relative to the corresponding parent proteins were studied in rabbits using a dual-isotope tracer technique. The capillary transfer rates and the partitions between intra- and extravascular spaces of these asialotransferrins did not differ significantly from the corresponding values for the control proteins but the asialotransferrins were catabolized faster. However, the difference in catabolic rates only amounted to 13–20%, which was in the same order as established previously for rabbit asialotransferrin (15%) but was considerably less than for human asialotransferrin (350%). This behavior clearly indicates that, in contradistinction to human asialotransferrin, bovine, canine, and porcine asialotransferrins are not eliminated from the plasma of rabbits via the Ashwell–Morell pathway for asialoglycoproteins.To explain the discrepancy in the behavior in vivo of the heterologous asialotransferrins, the carbohydrate compositions of the native proteins were measured and compared. The data show that bovine, porcine, dog, and rabbit transferrins contain approximately half the amount of carbohydrate found for the human protein. Furthermore, the human asialotransferrin carbohydrate chains terminate with galactosyl residues, which can be cleaved by β-galactosidase, whereas bovine, porcine, dog, and rabbit asialotransferrins do not liberate galactose in the presence of β-galactosidase.These observations are consistent with the hypothesis that the rapid elimination of a heterologous asialotransferrin can only be expected if the terminal galactose residues are accessible and that the slightly accelerated catabolism of homologous and certain heterologous asialotransferrins is due to loss of negative charge from the protein.

Studies of the Metabolism of Asialotransferrins: Potentiation of the Catabolism of Human Asialotransferrin in the Rabbit

1974 ◽  
Vol 52 (3) ◽  
pp. 155-161 ◽  
Author(s):  
E. Regoeczi ◽  
M. W. C. Hatton ◽  
K.-L. Wong
Keyword(s):  
Tracer Technique ◽  
Transfer Rates ◽  
Dual Isotope ◽  
Human Transferrin ◽  
Isotope Tracer ◽  
Human Control ◽  
Homologous Protein ◽  
Catabolic Rate ◽  
The Difference ◽  
Control Protein

The catabolism and distribution of simultaneously injected rabbit transferrin and rabbit asialotransferrin was studied in five rabbits using a dual-isotope tracer technique. Similar studies were performed with human transferrin and human asialotransferrin in two humans, seven rabbits, and a rat.In all experiments, the catabolic rate of the asialotransferrin was higher than the corresponding value for the control protein. The difference averaged at 15% for rabbits and 29% for humans when homologous protein preparations were used. There were no concomitant differences in capillary transfer rates or in the partition of the labeled proteins between intra- and extravascular spaces.The catabolic rate of human transferrin in rabbits was not significantly different from that of the corresponding homologous protein. In contrast, human transferrin from which 92–100% of the sialyl residues had been removed was catabolized in rabbits at approximately 3.5 times the rate for homologous asialotransferrin. Substantial difference was found between the elimination of human control and asialotransferrins in the rat as well.

Studies of the Metabolism of Asialotransferrins: the in Vivo Behavior of Baboon and Rhesus Asialotransferrins

1975 ◽  
Vol 53 (12) ◽  
pp. 1255-1261 ◽  
Author(s):  
E. Regoeczi ◽  
M. W. C. Hatton ◽  
K.-L. Wong
Keyword(s):  
Hepatic Uptake ◽  
Average Increase ◽  
Tracer Technique ◽  
Short Term ◽  
Dual Isotope ◽  
Isotope Tracer ◽  
Catabolic Rate ◽  
Nonprimate Mammal ◽  
Reduced Data

The catabolism and distribution of rhesus and baboon asialotransferrins relative to the corresponding parent proteins were studied in rabbits using a dual isotope tracer technique. Also a similar study with the baboon proteins in a baboon is reported.The metabolic data obtained in rabbits with both rhesus and baboon transferrins was close to the values established in a previous study for rabbit transferrin. Desialylation resulted in an average increase in the fractional catabolic rate of rhesus transferrin by 22.7%. This change is similar to that found earlier with asialotransferrins from several nonprimate mammals which are thought not to interact with the hepatic asialoglycoprotein receptor.Two kinetically distinct fractions were identified in baboon asialotransferrin. One of these, amounting to approximately one-third of the protein, was eliminated from the circulation very rapidly. The remaining two-thirds constituted a slowly catabolized fraction which behaved in vivo similarly to rhesus asialotransferrin. Unlike the rapidly cleared fraction, elimination of the slowly catabolized fraction in baboon asialotransferrin is probably not mediated by the hepatic asialoglycoprotein receptor. An amount comparable to the rapidly eliminated fraction in baboon asialotransferrin was recovered with the liver of rats in short-term experiments. In rats which were preinjected with chicken acid α1-glycoprotein the hepatic uptake of baboon asialotransferrin was markedly reduced. Data obtained in the baboon agreed with the findings in rabbits, although transferrin turnover was slower in the baboon.From its behavior in vivo as an asialoglycoprotein, baboon transferrin shows greater resemblance to human transferrin than rhesus transferrin. This conclusion is supported by carbohydrate analyses which show an intermediate position for baboon transferrin between man and a nonprimate mammal (rabbit), and a similarity between rhesus and rabbit transferrins.

Enhancement of ADP-induced Platelet Aggregation by Adrenaline in Vivo and Its Prevention

1973 ◽  
Vol 29 (02) ◽  
pp. 490-498 ◽  
Author(s):  
Hiroh Yamazaki ◽  
Itsuro Kobayashi ◽  
Tadahiro Sano ◽  
Takio Shimamoto
Keyword(s):  
Platelet Count ◽  
Platelet Aggregation ◽  
Platelet Rich Plasma ◽  
The Other ◽  
Endothelial Surface ◽  
Important Interaction ◽  
Blood Coagulability ◽  
The Difference

SummaryThe authors previously reported a transient decrease in adhesive platelet count and an enhancement of blood coagulability after administration of a small amount of adrenaline (0.1-1 µg per Kg, i. v.) in man and rabbit. In such circumstances, the sensitivity of platelets to aggregation induced by ADP was studied by an optical density method. Five minutes after i. v. injection of 1 µg per Kg of adrenaline in 10 rabbits, intensity of platelet aggregation increased to 115.1 ± 4.9% (mean ± S. E.) by 10∼5 molar, 121.8 ± 7.8% by 3 × 10-6 molar and 129.4 ± 12.8% of the value before the injection by 10”6 molar ADP. The difference was statistically significant (P<0.01-0.05). The above change was not observed in each group of rabbits injected with saline, 1 µg per Kg of 1-noradrenaline or 0.1 and 10 µg per Kg of adrenaline. Also, it was prevented by oral administration of 10 mg per Kg of phenoxybenzamine or propranolol or aspirin or pyridinolcarbamate 3 hours before the challenge. On the other hand, the enhancement of ADP-induced platelet aggregation was not observed in vitro, when 10-5 or 3 × 10-6 molar and 129.4 ± 12.8% of the value before 10∼6 molar ADP was added to citrated platelet rich plasma (CPRP) of rabbit after incubation at 37°C for 30 second with 0.01, 0.1, 1, 10 or 100 µg per ml of adrenaline or noradrenaline. These results suggest an important interaction between endothelial surface and platelets in connection with the enhancement of ADP-induced platelet aggregation by adrenaline in vivo.

Reliability of a Single β-Thromboglobulin Measurement in a Diabetic Population : Importance of PGE1 in Anticoagulant Mixture

1987 ◽  
Vol 57 (02) ◽  
pp. 201-204 ◽  
Author(s):  
P Y Scarabin ◽  
L Strain ◽  
C A Ludlam ◽  
J Jones ◽  
E M Kohner
Keyword(s):  
In Vitro Release ◽  
Mean Value ◽  
Reliable Estimate ◽  
Diabetic Patients ◽  
Single Measurement ◽  
Diabetic Population ◽  
The Difference ◽  
Vitro Release

SummaryDuring the collection of samples for plasma β-thromboglobulin (β-TG) determination, it is well established that artificially high values can be observed due to in-vitro release. To estimate the reliability of a single β-TG measurement, blood samples were collected simultaneously from both arms on two separate occasions in 56 diabetic patients selected for a clinical trial. From each arm, blood was taken into two tubes containing an anticoagulant mixture with (tube A) and without (tube B) PGE!. The overall mean value of B-TG in tube B was 1.14 times higher than in tube A (p <0.01). The markedly large between-arms variation accounted for the most part of within-subject variation in both tubes and was significantly greater in tube B than in tube A. Based on the difference between B-TG values from both arms, the number of subjects with artifically high B-TG values was significantly higher in tube B than in tube A on each occasion (overall rate: 28% and 14% respectively). Estimate of between-occasions variation showed that B-TG levels were relatively stable for each subject between two occasions in each tube. It is concluded that the use of PGEi decreases falsely high B-TG levels, but a single measurement of B-TG does not provide a reliable estimate of the true B-TG value in vivo.

scholarly journals Interaction of 4-hydroxynonenal-modified low-density lipoproteins with the fibroblast apolipoprotein B/E receptor

1986 ◽  
Vol 234 (1) ◽  
pp. 245-248 ◽  
Author(s):  
W Jessup ◽  
G Jurgens ◽  
J Lang ◽  
H Esterbauer ◽  
R T Dean
Keyword(s):  
Apolipoprotein B ◽  
Negative Charge ◽  
Low Density Lipoprotein ◽  
Ldl Receptor ◽  
Density Lipoprotein ◽  
Low Density ◽  
Lipid Peroxidation Product ◽  
Modified Low Density Lipoproteins ◽  
Peroxidation Product

The incorporation of the lipid peroxidation product 4-hydroxynonenal into low-density lipoprotein (LDL) increases the negative charge of the particle, and decreases its affinity for the fibroblast LDL receptor. It is suggested that this modification may occur in vivo, and might promote atherogenesis.

Critical Technical Issues in High Voltage SiC Power Devices

2008 ◽  
Vol 600-603 ◽  
pp. 895-900 ◽  
Author(s):  
Anant K. Agarwal ◽  
Albert A. Burk ◽  
Robert Callanan ◽  
Craig Capell ◽  
Mrinal K. Das ◽  
...  
Keyword(s):  
Threshold Voltage ◽  
Carrier Mobility ◽  
Negative Charge ◽  
State Of The Art ◽  
Power Devices ◽  
Power Mosfets ◽  
Large Numbers ◽  
Technical Issues ◽  
The Difference ◽  
Difficult Issue

In this paper, we review the state of the art of SiC switches and the technical issues which remain. Specifically, we will review the progress and remaining challenges associated with SiC power MOSFETs and BJTs. The most difficult issue when fabricating MOSFETs has been an excessive variation in threshold voltage from batch to batch. This difficulty arises due to the fact that the threshold voltage is determined by the difference between two large numbers, namely, a large fixed oxide charge and a large negative charge in the interface traps. There may also be some significant charge captured in the bulk traps in SiC and SiO2. The effect of recombination-induced stacking faults (SFs) on majority carrier mobility has been confirmed with 10 kV Merged PN Schottky (MPS) diodes and MOSFETs. The same SFs have been found to be responsible for degradation of BJTs.

scholarly journals Force Generation on the Hallux Is More Affected by the Ankle Joint Angle than the Lesser Toes: An In Vivo Human Study

Biology ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 48
Author(s):  
Junya Saeki ◽  
Soichiro Iwanuma ◽  
Suguru Torii
Keyword(s):  
Repeated Measures ◽  
Joint Angle ◽  
Plantar Flexion ◽  
Human Study ◽  
Force Generation ◽  
Functional Difference ◽  
Multiple Comparison Test ◽  
The Difference ◽  
Metatarsophalangeal Joints

The structure of the first toe is independent of that of the other toes, while the functional difference remains unclear. The purpose of this study was to investigate the difference in the force generation characteristics between the plantar-flexion of the first and second–fifth metatarsophalangeal joints (MTPJs) by comparing the maximal voluntary plantar-flexion torques (MVC torque) at different MTPJs and ankle positions. The MVC torques of the first and second–fifth MTPJs were measured at 0°, 15°, 30°, and 45° dorsiflexed positions of the MTPJs, and at 20° plantar-flexed, neutral, and 20° dorsiflexed positions of the ankle. Two-way repeated measures analyses of variance with Holm’s multiple comparison test (MTPJ position × ankle position) were performed. When the MTPJ was dorsiflexed at 0°, 15°, and 30°, the MVC torque of the first MTPJ when the ankle was dorsiflexed at 20° was higher than that when the ankle was plantar-flexed at 20°. However, the ankle position had no significant effect on the MVC torque of the second–fifth MTPJ. Thus, the MVC torque of the first MTPJ was more affected by the ankle position than the second–fifth MTPJs.

scholarly journals Reaction of Chalcones with Cellular Thiols. The Effect of the 4-Substitution of Chalcones and Protonation State of the Thiols on the Addition Process. Diastereoselective Thiol Addition

Molecules ◽  
2021 ◽  
Vol 26 (14) ◽  
pp. 4332
Author(s):  
Fatemeh Kenari ◽  
Szilárd Molnár ◽  
Pál Perjési
Keyword(s):  
Biological Effects ◽  
Equilibrium Composition ◽  
Deprotonated Form ◽  
Degree Of Ionization ◽  
Thiol Reactivity ◽  
Michael Type Addition ◽  
Ph Conditions ◽  
The Difference ◽  
Initial Reactivity

Several biological effects of chalcones have been reported to be associated with their thiol reactivity. In vivo, the reactions can result in the formation of small-molecule or protein thiol adducts. Both types of reactions can play a role in the biological effects of this class of compounds. Progress of the reaction of 4-methyl- and 4-methoxychalcone with glutathione and N-acetylcysteine was studied by the HPLC-UV-VIS method. The reactions were conducted under three different pH conditions. HPLC-MS measurements confirmed the structure of the formed adducts. The chalcones reacted with both thiols under all incubation conditions. The initial rate and composition of the equilibrium mixtures depended on the ratio of the deprotonated form of the thiols. In the reaction of 4-methoxychalcone with N-acetylcysteine under strongly basic conditions, transformation of the kinetic adduct into the thermodynamically more stable one was observed. Addition of S-protonated N-acetylcysteine onto the polar double bonds of the chalcones showed different degrees of diastereoselectivity. Both chalcones showed a Michael-type addition reaction with the ionized and non-ionized forms of the investigated thiols. The initial reactivity of the chalcones and the equilibrium composition of the incubates showed a positive correlation with the degree of ionization of the thiols. Conversions showed systematic differences under each set of conditions. The observed differences can hint at the difference in reported biological actions of 4-methyl- and 4-methoxy-substituted chalcones.

scholarly journals Enamel interproximal reduction during treatment with clear aligners: digital planning versus OrthoCAD analysis

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Giuseppina Laganà ◽  
Arianna Malara ◽  
Roberta Lione ◽  
Carlotta Danesi ◽  
Simonetta Meuli ◽  
...  
Keyword(s):  
Treatment Plan ◽  
End Of Treatment ◽  
The Mean ◽  
The Difference ◽  
Dependent Sample ◽  
University Of Rome ◽  
The University ◽  
Enamel Reduction ◽  
Lower Arch

Abstract Background The aim of the study was to compare the amount of interproximal enamel reduction (IPR) provided on ClinCheck software with the amount of IPR carried out by the orthodontist during treatment with clear aligners. Methods 30 subjects (14 males, 16 females; mean age of 24.53 ± 13.41 years) randomly recruited from the Invisalign account of the Department of Orthodontics at the University of Rome “Tor Vergata” from November 2018 to October 2019, were collected according to the following inclusion criteria: mild to moderate dento-alveolar discrepancy (1.5–6.5 mm); Class I canine and molar relationship; full permanent dentition (excluding third molars); both arches treated only using Comprehensive Package by Invisalign system; treatment plan including IPR. Pre- (T0) and post-treatment (T1) digital models (.stl files), created from an iTero scan, were collected from all selected patients. The OrthoCAD digital software was used to measure tooth mesiodistal width in upper and lower arches before (T0) and at the end of treatment (T1) before any refinement. The widest mesio-distal diameter was measured for each tooth excluding molars by “Diagnostic” OrthoCAD tool. The total amount of IPR performed during treatment was obtained comparing the sum of mesio-distal widths of all measured teeth at T0 and T1. Significant T1–T0 differences were tested with dependent sample t-test (P < 0.05). Results In the upper arch, IPR was digitally planned on average for 0.62 mm while in the lower arch was on average for 1.92 mm. As for the amount of enamel actually removed after IPR performing, it was on average 0.62 mm in the maxillary arch. In the mandibular arch, the mean of IPR carried out was 1.93 mm. The difference between planned IPR and performed IPR is described: this difference was on average 0.00 mm in the upper arch and 0.01 in the lower arch. Conclusions The amount of enamel removed in vivo corresponded with the amount of IPR planned by the Orthodontist using ClinCheck software.

scholarly journals Phosphorylation and an ATP-dependent process increase the dynamic exchange of H1 in chromatin

2002 ◽  
Vol 158 (7) ◽  
pp. 1161-1170 ◽  
Author(s):  
Yali Dou ◽  
Josephine Bowen ◽  
Yifan Liu ◽  
Martin A. Gorovsky
Keyword(s):  
Negative Charge ◽  
Histone H1 ◽  
Linker Histone ◽  
Global Effect ◽  
Dynamic Binding ◽  
Linker Histone H1 ◽  
Dependent Process ◽  
Dynamic Exchange

In Tetrahymena cells, phosphorylation of linker histone H1 regulates transcription of specific genes. Phosphorylation acts by creating a localized negative charge patch and phenocopies the loss of H1 from chromatin, suggesting that it affects transcription by regulating the dissociation of H1 from chromatin. To test this hypothesis, we used FRAP of GFP-tagged H1 to analyze the effects of mutations that either eliminate or mimic phosphorylation on the binding of H1 to chromatin both in vivo and in vitro. We demonstrate that phosphorylation can increase the rate of dissociation of H1 from chromatin, providing a mechanism by which it can affect H1 function in vivo. We also demonstrate a previously undescribed ATP-dependent process that has a global effect on the dynamic binding of linker histone to chromatin.

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