CHARACTERIZATION OF SERUM PROSTACYCLIN BINDING DEFECTS IN THROMBOTIC THROMBOCYTOPENIC PURPURA (TTP)

1987 ◽  
Author(s):  
K Wu ◽  
C Manner ◽  
A Tsai
Keyword(s):  
Gel Filtration ◽  
Mean Value ◽  
Binding Activity ◽  
Normal Serum ◽  
Buffer Solution ◽  
Single Class ◽  
Filtration Method ◽  
Serial Serum ◽  
The Mean ◽  
Wall Interaction

To understand further the pathophysiologic significance of PGI2 binding defects in TTP, we measured serum PGI2 binding activity in 12 TTP patients and matched controls. Serum binding of PGI2 was measured by Sephadex G-25 gel filtration. The mean binding activity in 33 healthy subjects ages 20-40 years was 39.9 ± S.D 4.4%. The mean value of TTP (n=12) was significantly lower (26.2 ± 4.1, P <0.01). Serum from 5 severe ITP, 5 DIC and 5 thrombocythemia exhibited normal binding ctivity. To determine the binding kinetics we utilized 3H-iloprost in a gel filtration method described by Hirose and Kano (Biochim. Biophys. Acta. 751:376, 1971). To 50 mg of Sephadex G-50, 0.435 ml of 50mM Tris buffer (pH 7.4) was added. After swelling of the gel was completed 0.195 ml of the buffer solution containing serum and 3H-iloprost was added. The sample was mixed and the protein and ligand concentration was determined. The computer fitting of the binding isotherm according to the originally proposed equation yielded a binding curve consistent with a single class of binding sites. The Kd value of normal serum was 70 μM and the B 48 nmol/ml. Acute TTP serum exhibited a reduced bindingXaffinity (Kd 236 μM) and a slightly elevated capacity (Bmax 85 nmols/ml). The binding parameters improved following successful treatment but the Kd remained subnormal (120 μM). These data indicate that reduced PGI2 binding activity is due to lower affinity of the PGI2 binding proteins. The relationship between defective PGI2 binding activity and PGI2 production was then evaluated. Serial serum and 24 hour urine were collected. Urinary samples were extracted and their 6-Keto-PGF1α (6KP) and thromboxane TXB2 levels were measured by RIA. TTP patients in remission had normal levels of urinary 6KP and TXB2 while urinary 6KP and TXB2 were elevated in relapsing TTP. Defective binding was noted when relapse began to occur while elevated 6KP and TXB2 were noted 48 hrs later. Both 6KP and TXB2 were normalized when the disease was controlled. Our findings indicate that defective PGI2 binding plays an important role in causing excessive platelet activation and platelet-vessel wall interaction in TTP.

Effect of 1,25-(OH)2D3 on jejunal absorption of magnesium in patients with chronic renal disease

1980 ◽  
Vol 238 (4) ◽  
pp. G349-G352 ◽  
Author(s):  
A. C. Schmulen ◽  
M. Lerman ◽  
C. Y. Pak ◽  
J. Zerwekh ◽  
S. Morawski ◽  
...  
Keyword(s):  
Vitamin D ◽  
Renal Disease ◽  
Chronic Renal Disease ◽  
Normal Subjects ◽  
Mean Value ◽  
Normal Serum ◽  
Perfusion Technique ◽  
Dihydroxyvitamin D3 ◽  
Jejunal Absorption ◽  
The Mean

These studies were performed to see if jejunal malabsorption of magnesium in patients with chronic renal disease was influenced by therapy with 1 alpha, 25-dihydroxyvitamin D3 [1,25-(OH)2D3; 2 microgram/day by mouth for 7 days]. This treatment restored normal serum concentrations of the vitamin D metabolite from 0.9 +/- 0.2 to 4.2 +/- 0.6 ng/dl. Jejunal absorption of magnesium, measured by a triple-lumen constant-perfusion technique, was enhanced in each of the seven patients by this therapy. The mean value rose from 0.04 +/- 0.02 to 0.13 +/- 0.02 mmol . 30 cm-1 . h-1. This last value is similar to the magnesium absorption rate in untreated normal subjects. These results demonstrate that magnesium absorption in the human jejunum is dependent on vitamin D, and they show that 1 alpha,25-dihydroxyvitamin D3 therapy in patients with chronic renal failure is associated with an enhanced jejunal absorption of magnesium.

scholarly journals Selection of Membrane RNA Aptamers to Amyloid Beta Peptide: Implications for Exosome-Based Antioxidant Strategies

2019 ◽  
Vol 20 (2) ◽  
pp. 299 ◽  
Author(s):  
Teresa Janas ◽  
Karolina Sapoń ◽  
Michael Stowell ◽  
Tadeusz Janas
Keyword(s):  
Amyloid Beta ◽  
Gel Filtration ◽  
Membrane Receptors ◽  
Rna Aptamers ◽  
Amyloid Peptide ◽  
Amyloid Beta Peptide ◽  
Buffer Solution ◽  
Filtration Method ◽  
Beta Peptide ◽  
Selection Of

The distribution of amyloid beta peptide 42 (Aβ42) between model exosomal membranes and a buffer solution was measured. The model membranes contained liquid-ordered regions or phosphatidylserine. Results demonstrated that up to ca. 20% of amyloid peptide, generated in the plasma (or intracellular) membrane as a result of proteolytic cleavage of amyloid precursor proteins by β- and γ-secretases, can stay within the membrane milieu. The selection of RNA aptamers that bind to Aβ42 incorporated into phosphatidylserine-containing liposomal membranes was performed using the selection-amplification (SELEX) method. After eight selection cycles, the pool of RNA aptamers was isolated and its binding to Aβ42-containing membranes was demonstrated using the gel filtration method. Since membranes can act as a catalytic surface for Aβ42 aggregation, these RNA aptamers may inhibit the formation of toxic amyloid aggregates that can permeabilize cellular membranes or disrupt membrane receptors. Strategies are proposed for using functional exosomes, loaded with RNA aptamers specific to membrane Aβ42, to reduce the oxidative stress in Alzheimer’s disease and Down’s syndrome.

A NOTE ON THE ENERGY OF ACTIVATION OF THE AMYLASE IN VARIOUS HUMAN BODY FLUIDS

1956 ◽  
Vol 34 (1) ◽  
pp. 6-9 ◽  
Author(s):  
Leslie Kovacs ◽  
Jules Tuba
Keyword(s):  
Activation Energy ◽  
Human Body ◽  
Mean Value ◽  
Body Fluids ◽  
Normal Serum ◽  
The Body ◽  
Energy Of Activation ◽  
Heat Inactivation ◽  
Head Of The Pancreas ◽  
The Mean

The activation energy was determined for the amylase present in the following fluids obtained from the human body: urine, duodenal fluid, saliva, and normal serum, as well as serum from patients with mumps, acute pancreatitis, and carcinoma of the head of the pancreas. Over a temperature range of 4°–37.4 °C., with starch as a substrate, the value of the energy of activation was similar in all cases to that for bacterial α-amylase, and the mean value was 13,740 ± 200 cal./mole. Partial heat inactivation of the enzyme was evident in some cases at 37.4°. On the basis of the evidence obtained it appears that α-amylase is present in all the body fluids examined.

Biochemical Study of Protease Inhibitors in Normal Chinchilla Middle Ear

1989 ◽  
Vol 98 (6) ◽  
pp. 472-478 ◽  
Author(s):  
Yukiyoshi Hamaguchi ◽  
Steven K. Juhn ◽  
Yasuo Sakakura
Keyword(s):  
Middle Ear ◽  
Protein Concentration ◽  
Biochemical Study ◽  
Mean Value ◽  
Binding Activity ◽  
Trypsin Inhibitors ◽  
Middle Ear Mucosa ◽  
Α2 Macroglobulin ◽  
The Mean ◽  
Antitryptic Activity

Protein concentration and inhibitory capacity of both α1-antitrypsin (α1-AT) and α2-macroglobulin (α2-M) were measured in plasma and middle ear bulla (MEB) washings of chinchillas by use of specific antisera against chinchilla α1-AT and α2-M. Low molecular weight (LMW) trypsin inhibitor also was analyzed in MEB washings. Chinchilla α2-M showed a common antigenicity with human α2-M. The mean value of α1-AT in chinchilla plasma was 412.0 ± 87.8 and that of α2-M was 435.0 ± 117.1 mg/dL. There was a significant relationship between α-AT level and antitryptic activity, and between α2-M level and trypsin binding activity in plasma. The majority of α1-AT and α2-M in plasma is present as free inhibitors unsaturated with proteases. The MEB washings had significant antitryptic activity, which is attributed to both α1-AT and LMW trypsin inhibitors. Inhibitory functions of α1-AT and LMW trypsin inhibitors appear to play an important role in the defense of the normal middle ear mucosa.

SUBCLINICAL HYPOTHYROIDISM IN ADDISON'S DISEASE

1979 ◽  
Vol 91 (4) ◽  
pp. 674-679 ◽  
Author(s):  
Jens Faber ◽  
Dorte Cohn ◽  
Carsten Kirkegaard ◽  
Morten Christy ◽  
Kaj Siersbæk-Nielsen ◽  
...  
Keyword(s):  
Addison’S Disease ◽  
Mean Value ◽  
Normal Serum ◽  
Control Group ◽  
Addison's Disease ◽  
Normal Range ◽  
Microsomal Antibody ◽  
The Mean ◽  
Thyroid Microsomal Antibodies ◽  
Serum Tsh

ABSTRACT Fourteen patients with Idiopatic Addison's disease (IAD) were studied in order to detect a possible subclinical hypothyroid state. All were clinically euthyroid with normal serum thyroxine (T4) and serum 3,5′,3′-triiodothyronine (T3). Eleven had circulating thyroid microsomal antibodies in blood. The mean basal serum TSH was significantly higher than that of the control group but only three patients had values above the upper normal range. The mean value of serum T4 was decreased as compared to that of the normal persons, while serum 3,3′,5′-triiodothyronine was elevated. 7.5 mU bovine thyrotrophin per kilogram body weight injected intravenously caused a rise in serum T3 not different from the response in normals. However, as well increasing serum TSH as increasing microsomal antibody titer correlated significantly to decreasing thyroidal release of T3. Our results suggest that clinically euthyroid patients suffering from IAD might have a beginning thyroidal insufficiency because of a progressive immunological damage of the thyroid.

scholarly journals Serum Adenosine Deaminase Values in Healthy People

2020 ◽  
Keyword(s):  
Adenosine Deaminase ◽  
Healthy Subjects ◽  
Reference Range ◽  
Mean Value ◽  
Normal Serum ◽  
Healthy People ◽  
Reference Ranges ◽  
Percentile Method ◽  
The Mean ◽  
Almost All

The purpose of this study is to determine the activity of serum adenosine deaminase (ADA) in healthy people, in connection with significant differences in published reference ranges from different authors. In our study, we examined 160 healthy subjects aged 18 to 84, of whom 64 were men and 96 women. We have determined serum adenosine deaminase levels using a method based on the ability of the enzyme adenosine deaminase to catalyze the deamination of adenosine to inosine and ammonia. The catalytic concentration is determined spectrophotometrically by the rate of reduction of NADH measured at 340 nm. We found that normal serum ADA values among our healthy subjects are higher than the recommended reference range for the method we use, namely below 18 U/l. Using the percentile method, we worked out the following reference ranges: for women 14.53 - 25.73 U/l and for men 18.46 – 27.50 U/l. For women, the mean value is 21.07 U/l, and for men 21.30 U/l. At 95% CI, the serum ADA values of almost all subjects included in the study are within the recommended and other authors range of 11.50 - 25.00 U/l.

scholarly journals A high-affinity oestrogen-binding protein in cockerel liver cytosol

1979 ◽  
Vol 180 (2) ◽  
pp. 347-353 ◽  
Author(s):  
C B Lazier ◽  
A J Haggarty
Keyword(s):  
Binding Sites ◽  
Proteinase Inhibitors ◽  
Specific Binding ◽  
Binding Protein ◽  
Gel Filtration ◽  
Binding Activity ◽  
Single Class ◽  
High Affinity ◽  
Significant Concentration

In contrast with several earlier reports, cytosol from cockerel liver contains a significant concentration of a protein that binds oestradiol with high affinity. To demonstrate the activity, certain alterations in the conventional method of preparation of cytosol must be made. Homogenization in sucrose-containing buffer at pH 8.4 in the presence of proteinase inhibitors and rapid fractionation of the cytosol with (NH4)2SO4 enables demonstration of a single class of oestradiol-binding sites with a Kd of about 1 nM and specificity only for oestrogens. The concentration is about 300 sites per cell in liver from 2-week-old cockerels. Oestradiol treatment in vivo decreases the number of exchangeable cytosol oestradiol-binding sites by about 80% for 1–4h, after which time it is gradually restored. Gel filtration of the cytosol preparation in the presence of high salt concentrations reveals that most of the oestradiol-binding activity is in high-molecular-weight aggregates, but a mild trypsin treatment generates a specific binding protein with an approximate mol.wt. of 40 000. This protein may be an oestrogen receptor.

A NOTE ON THE ENERGY OF ACTIVATION OF THE AMYLASE IN VARIOUS HUMAN BODY FLUIDS

1956 ◽  
Vol 34 (1) ◽  
pp. 6-9 ◽  
Author(s):  
Leslie Kovacs ◽  
Jules Tuba
Keyword(s):  
Activation Energy ◽  
Human Body ◽  
Mean Value ◽  
Body Fluids ◽  
Normal Serum ◽  
The Body ◽  
Energy Of Activation ◽  
Heat Inactivation ◽  
Head Of The Pancreas ◽  
The Mean

The activation energy was determined for the amylase present in the following fluids obtained from the human body: urine, duodenal fluid, saliva, and normal serum, as well as serum from patients with mumps, acute pancreatitis, and carcinoma of the head of the pancreas. Over a temperature range of 4°–37.4 °C., with starch as a substrate, the value of the energy of activation was similar in all cases to that for bacterial α-amylase, and the mean value was 13,740 ± 200 cal./mole. Partial heat inactivation of the enzyme was evident in some cases at 37.4°. On the basis of the evidence obtained it appears that α-amylase is present in all the body fluids examined.

HEMOLYTIC ASSAY OF THE NINTH COMPLEMENT COMPONENT: ELEVATION AND DEPLETION IN RHEUMATIC DISEASES

1971 ◽  
Vol 134 (3) ◽  
pp. 259-275 ◽  
Author(s):  
Shaun Ruddy ◽  
Lloyd K. Everson ◽  
Peter H. Schur ◽  
K. Frank Austen
Keyword(s):  
Renal Disease ◽  
Rheumatic Diseases ◽  
Fluid Phase ◽  
Kinetic Studies ◽  
Mean Value ◽  
Normal Serum ◽  
Normal Range ◽  
Hemolytic Assay ◽  
Normal Individuals ◽  
The Mean

An effective molecule titration for the ninth component of complement in the biologic fluids of man was developed using EAC1-8 cells produced by treating EAC14 cells with a chromatographic fraction of human serum containing C2, C3, C5, C6, C7, and C8. Kinetic studies of the interaction of EAC1-8 with C9 indicated that this component was depleted from the fluid phase, and that the lytic reaction proceeded most rapidly at ionic strength 0.145, and at a temperature of 37°C. The mean value for C9 in normal serum was 52,000 ±12,000 units/ml. The mean serum C9 for patients with DJD, rheumatoid arthritis, or SLE without active renal disease was approximately twice the mean for normal individuals. Patients with SLE and active renal disease had a mean C9 value which fell within the normal range, but was significantly lower than in patients with SLE who did not have active renal disease. Two instances of absolutely subnormal C9 levels were observed in patients during attacks of florid SLE, including nephritis. Since the usual change in serum C9 in rheumatic diseases is a marked elevation, the occurrence of a subnormal value reflects circumstances in which depletion due to activation of the sequence exceeds the increases associated with the inflammatory response.

Long-period modulated superstructures in Pd-12.5 at.%Ce and Pd-15 at.%Ce alloys

1990 ◽  
Vol 48 (4) ◽  
pp. 164-165
Author(s):  
Noriyuki Kuwano ◽  
Masaru Itakura ◽  
Kensuke Oki
Keyword(s):  
Electron Microscopy ◽  
Mean Value ◽  
Heavy Elements ◽  
Arc Furnace ◽  
X Ray ◽  
Long Period ◽  
Ultra High Purity ◽  
Heat Treated ◽  
Atomic Scattering ◽  
The Mean

Pd-Ce alloys exhibit various anomalies in physical properties due to mixed valences of Ce, and the anomalies are thought to be strongly related with the crystal structures. Since Pd and Ce are both heavy elements, relative magnitudes of (fcc-fpd) are so small compared with <f> that superlattice reflections, even if any, sometimes cannot be detected in conventional x-ray powder patterns, where fee and fpd are atomic scattering factors of Ce and Pd, and <f> the mean value in the crystal. However, superlattices in Pd-Ce alloys can be analyzed by electron microscopy, thanks to the high detectability of electron diffraction. In this work, we investigated modulated superstructures in alloys with 12.5 and 15.0 at.%Ce.Ingots of Pd-Ce alloys were prepared in an arc furnace under atmosphere of ultra high purity argon. The disc specimens cut out from the ingots were heat-treated in vacuum and electrothinned to electron transparency by a jet method.

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