Artificial pulmonary surfactant inhibited by proteins

1987 ◽  
Vol 62 (2) ◽  
pp. 429-437 ◽  
Author(s):  
T. Fuchimukai ◽  
T. Fujiwara ◽  
A. Takahashi ◽  
G. Enhorning
Keyword(s):  
Surface Tension ◽  
Human Serum ◽  
Serum Protein ◽  
Pulmonary Surfactant ◽  
Protein Concentration ◽  
Mean Value ◽  
Surfactant Preparation ◽  
The Mean ◽  
Potential Inhibitors ◽  
Dose Dependent

With a pulsating bubble surfactometer we assessed the ability of various agents, fibrinogen, human serum, albumin, and a 55,000-dalton serum protein, to interfere with the surface activity of Surfactant TA. From a highest final protein concentration of 4 mg/ml the potential inhibitors were diluted down to 0.125 mg/ml in six steps, and each concentration was evaluated together with two final phospholipid concentrations, 6.25 and 1.25 mg/ml, of the surfactant preparation. The strongest inhibiting action was exerted by fibrinogen, followed by human serum and the 55,000-dalton serum protein; the weakest inhibitor was albumin. Bilirubin, when added in an amount of 1.73 mg/100 ml dissolved in human serum, significantly (P less than 0.001) augmented the inhibition over that exerted by human serum alone. Adsorption rate, as reflected in the mean value of surface tension 2 and 10 s after creation of a bubble, not pulsating, was seriously affected by each of the protein-containing inhibitors in concentrations exceeding 1 mg/ml. Surface tension was raised significantly when the pulsating bubble was at maximal and minimal size. The effect was dose dependent. At maximal size it showed no tendency to disappear during the 10-min recording, but at minimal bubble size the inhibition gradually diminished. We conclude that proteins present in the airways may seriously interfere with the activity of Surfactant TA.

A pharmacokinetic study of Genetaxyl (G) together with cyclosporin A (CsA) administered orally in cancer patients

2006 ◽  
Vol 24 (18_suppl) ◽  
pp. 12002-12002
Author(s):  
C. Liau ◽  
E. Lepper ◽  
H. Wang ◽  
M. Yang ◽  
T. Chiou ◽  
...  
Keyword(s):  
Equilibrium Dialysis ◽  
Volume Of Distribution ◽  
Mean Value ◽  
Phase Ii Trials ◽  
Patients With Cancer ◽  
The Mean ◽  
High Concentrations ◽  
Apparent Bioavailability ◽  
Dose Levels ◽  
Dose Dependent

12002 Background: Oral administration of paclitaxel given with CsA has shown promising activity in Phase II trials, but the apparent bioavailability is low and dose-dependent due to the presence of high concentrations of Cremophor EL (CrEL). We hypothesized that the use of a novel oral paclitaxel formulation containing only 20% CrEL (Genetaxyl [G]; Genovate Biotechnology Ltd., Taiwan), given with CsA is associated with an improved pharmacokinetic (PK) profile. Methods: Cohorts of 6 patients with cancer were treated with oral G at a dose of 60, 120, or 180 mg/m2 and 10 mg/kg of oral CsA in cycle 1. In cycle 2, patients received IV G (175 mg/m2, 3-h infusion). Three additional patients received generic IV paclitaxel (GIP). Serial blood samples were analyzed by LC/MS/MS and equilibrium dialysis, to determine total and unbound paclitaxel PK. Results: The mean (± SD) total paclitaxel AUCs were 1299±189, 1682±636, and 2204±1407 ng.h/mL at the 3 consecutive dose levels, suggesting nonlinear PK. However, based on unbound AUC, the oral bioavailability was dose-independent (P=.62), with a mean value of 37.2±18.6% (n=15). As expected, the total paclitaxel AUC following IV G (9024±4648 ng·h/mL) was lower than that for IV GIP (13,732±3983 ng·h/mL), as a result of increased clearance (39.6 vs 18.3 L/h) and a larger volume of distribution (768 vs 268 L). Interestingly, the unbound paclitaxel AUC was similar between the two IV formulations (P=.25), as the ratio of unbound/total paclitaxel for G was 2.5 times higher than that for GIP (12.5 vs 4.9%). Toxicity profiles were mild, with only 2 patients experiencing ≥ Gr 3 myelosuppression following oral G at 180 mg/m2. Conclusions: The mean bioavailability of paclitaxel following oral Genetaxyl with CsA was about 37%, which is higher than that observed previously with paclitaxel (range, 21–31%). Further clinical exploration of oral Genetaxyl in taxane-sensitive diseases is warranted. [Table: see text]

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.

scholarly journals Lactoferrin in Human Milk of Prolonged Lactation

Nutrients ◽  
2019 ◽  
Vol 11 (10) ◽  
pp. 2350 ◽  
Author(s):  
Czosnykowska-Łukacka ◽  
Orczyk-Pawiłowicz ◽  
Broers ◽  
Królak-Olejnik
Keyword(s):  
Human Milk ◽  
Protein Concentration ◽  
Mean Value ◽  
Mature Milk ◽  
Lactating Women ◽  
Solid Foods ◽  
Lactation Stage ◽  
Standard Value ◽  
The Mean ◽  
One Year

Among the immunologically important bioactive factors present in human milk, lactoferrin (Lf) has emerged as a key player with wide-ranging features that directly and indirectly protect the neonate against infection caused by a variety of pathogens. The concentration of Lf in human milk is lactation-stage related; colostrum contains more than 5 g/L, which then significantly decreases to 2–3 g/L in mature milk. The milk of mothers who are breastfeeding for more than one year is of a standard value, containing macronutrients in a composition similar to that of human milk at later stages. The aim of this study was to evaluate lactoferrin concentration in prolonged lactation from the first to the 48th month postpartum. Lactating women (n = 120) up to 48 months postpartum were recruited to the study. The mean value of lactoferrin concentration was the lowest in the group of 1–12 months of lactation (3.39 ± 1.43 g/L), significantly increasing in the 13–18 months group (5.55 ± 4.00 g/L; p < 0.006), and remaining at a comparable level in the groups of 19–24 month and over 24 months (5.02 ± 2.97 and 4.90 ± 3.18 g/L, respectively). The concentration of lactoferrin in mother’s milk also showed a positive correlation with protein concentration over lactation from the first to the 48th month (r = 0.3374; p = 0.0002). Our results demonstrate the high immunology potential of human milk during prolonged lactation and that Lf concentration is close to the Lf concentration in colostrum. Evidence of stable or rising immunoprotein levels during prolonged lactation provides an argument for foregoing weaning; however, breastfeeding must be combined with solid foods meet the new requirements of a rapidly growing six-month or older baby.

Behavior of Antithrombin III, Determined as Protein Concentration and Biologic Activity, in Subjects with Neoplastic Disease

1982 ◽  
Vol 68 (3) ◽  
pp. 205-209 ◽  
Author(s):  
Vittorio Pengo ◽  
Cosimo Guerra ◽  
Giuseppe Cartei ◽  
Mario Fiorentino
Keyword(s):  
Healthy Subjects ◽  
Protein Concentration ◽  
Antithrombin Iii ◽  
Mean Value ◽  
Neoplastic Disease ◽  
Biologic Activity ◽  
At Iii ◽  
Coagulation Proteins ◽  
The Mean

Antithrombin III (AT III), the primary inhibitor of plasma protease coagulation proteins, was evaluated in groups of patients with different neoplastic disease. When compared with that of 25 healthy subjects, the mean value of AT III biologic activity was elevated in all groups, significantly in gastrointestinal (p < 0.02) and lung (p < 0.001) tumors, lymphoma (p < 0.02) and in the group with various primary cancers (p < 0.05). No difference was found between 46 patients tested under chemoradiotherapy and 216 patients who had not undergone therapy for at least 1 month. Four patients with clinical thrombosis had normal AT III biologic activity. Of the 262 patients studied, 14 had low AT III biologic activity without clinical thrombosis and normal protein concentration. In 71 patients (27%) an excess of immunoassayable protein of 20% or more over biologic activity was found. Double immunoelectrophoresis performed in 5 of these showed for 3 patients an enlarged second arc of precipitation. Moreover, no correlation was observed between the activity and protein AT III concentration (r = 0.05). The likelihood of the presence of circulating AT III-protease complexes is discussed.

Reference values for fructosamine concentrations in children's sera: influence of protein concentration, age, and sex.

1988 ◽  
Vol 34 (12) ◽  
pp. 2444-2447 ◽  
Author(s):  
J De Schepper ◽  
M P Derde ◽  
P Goubert ◽  
F Gorus
Keyword(s):  
Reference Values ◽  
Protein Concentration ◽  
Reference Intervals ◽  
Mean Value ◽  
Age Dependency ◽  
Serum Total Protein ◽  
Normal Children ◽  
Glycated Protein ◽  
The Mean ◽  
Mean Concentration

Abstract Fructosamine and protein (total and fractionated) were measured in the serum of 170 normal children, ages two weeks to 15 years. The mean fructosamine concentration was 2.12 mmol/L, 5% lower than the mean value observed for adults. We observed no sex-related difference in fructosamine values, but saw a pronounced age dependency of reference values. For children younger than three years, the mean concentration of fructosamine was 15% lower than in adults, but glycated protein concentrations increased with age, reaching essentially adult values by age six years. Expressing fructosamine concentrations per gram of serum total protein or of albumin weakened the influence of age, but did not eliminate it completely. We report reference intervals for fructosamine concentrations in children's sera.

scholarly journals SURFACE TENSION OF SERUM

1924 ◽  
Vol 40 (1) ◽  
pp. 133-149 ◽  
Author(s):  
P. Lecomte du Noüy
Keyword(s):  
Surface Tension ◽  
Free Surface ◽  
Serum Proteins ◽  
Mean Value ◽  
Rabbit Serum ◽  
Absolute Minimum ◽  
Egg Albumin ◽  
Molecular Length ◽  
Protein Molecules ◽  
The Mean

An attempt was made to apply the assumption that a monolayer of serum exists at a certain dilution, in order to calculate the thickness of this layer or, that is to say, the mean value of one of the dimensions of the molecules of the serum proteins. The criterion taken for the existence of such a monolayer was the existence at a given concentration (1/11,000 for rabbit serum) of a maximum drop in the surface tension of serum solutions kept in watch-glasses. A series of preliminary experiments showed: 1. That the maximum drop in 2 hours took place, for the material used, at a concentration of 1/11,000, and that it always corresponded to an absolute minimum value of the surface tension of the solution, this minimum being quite sharp and well defined. 2. That adsorption took place on the glass as well as on the free surface of the liquid, and that apparently the same part of the molecule, in both cases, was drawn toward the water. 3. That the specific gravity of the anhydrous proteins of the rabbit serum studied was 1.275, whence it followed, on the basis of 6.51 per cent protein content, that the mean thickness of the protein molecules was 35.4 x 10–8 cm. The same method applied to crystalline egg albumin, pH 6.8, in water, gave 52.8 x 10–8 cm. for the probable molecular length.

scholarly journals Fluorometric Assay of Human Serum Carnosinase Activity in Normal Children, Adults and Patients with Myopathy

1984 ◽  
Vol 21 (6) ◽  
pp. 510-514 ◽  
Author(s):  
K Bando ◽  
T Shimotsuji ◽  
H Toyoshima ◽  
C Hayashi ◽  
K Miyai
Keyword(s):  
Muscular Dystrophy ◽  
Human Serum ◽  
Accurate Method ◽  
Mean Value ◽  
Adult Women ◽  
Normal Children ◽  
Adult Men ◽  
The Mean ◽  
Low Activity ◽  
Normal Adults

A sensitive, accurate method has been established for the assay of serum carnosinase by measuring the fluorescence emitted from the L-histidine liberated on treatment with o-phthaldialdehyde. Using this method the serum values for normal adults, infants and children were measured. The mean value was very low in infants of less than 1 year old but increased with age, being almost the same in children aged 6 years or more as in adults. In adult men, the mean activity was 1·85 μmol/mL/h and in adult women it was 2·07 μmol/mL/h. Low activity was observed in patients with muscular dystrophy.

A SURFACE TENSION EQUILIBRIUM STUDY OF HUMAN SERUM IN ATHEROSCLEROSIS

1959 ◽  
Vol 37 (7) ◽  
pp. 861-871
Author(s):  
J. J. Jasper ◽  
D. S. McCann ◽  
R. E. Mosher ◽  
A. J. Boyle
Keyword(s):  
Surface Tension ◽  
Protein Structure ◽  
Blood Serum ◽  
Human Serum ◽  
Serum Protein ◽  
Human Blood ◽  
Colloidal Stability ◽  
Rate Of Change ◽  
Equilibrium Study ◽  
Fresh Serum

The rate of attainment of a static surface tension equilibrium by human blood serum was investigated. In general serum from atherosclerotic individuals tends to reach a static surface tension value more rapidly than serum from a normal subject. From a consideration of typical surface tension versus age-of-surface curves of fresh serum, of heated denatured serum, and of aged serum, it is concluded that the rate of change of surface tension is a function of serum protein structure and therefore influences the colloidal stability of serum.

Three turbidimetric methods for determining total protein compared.

1985 ◽  
Vol 31 (8) ◽  
pp. 1377-1380 ◽  
Author(s):  
H H Nishi ◽  
R J Elin
Keyword(s):  
Human Serum Albumin ◽  
Serum Albumin ◽  
Human Serum ◽  
Serum Protein ◽  
Protein Concentration ◽  
Total Serum Protein ◽  
Total Serum ◽  
Benzethonium Chloride ◽  
Human Serum Protein ◽  
Biuret Method

Abstract We used human serum protein fractions to evaluate the sensitivity and bias of three turbidimetric methods for determining concentrations of proteins. Each fraction (Cohn Fractions II, III, IV, and V) was assigned a protein concentration value that was determined by the biuret method, which we calibrated with purified monomer of human serum albumin. All three turbidimetric methods (those involving sulfosalicylic acid/sodium sulfate, trichloroacetic acid, and alkaline benzethonium chloride) gave acceptable results for Fraction V with crystallized human serum albumin as the reference material, but there was bias by each of the three methods for the three globulin fractions. The method involving alkaline benzethonium chloride with measurement at 450 nm had the best sensitivity within the range of linearity and the most consistent bias among the three globulin fractions. These results define the dilemma for valid calibration of these methods for total serum protein in cerebrospinal fluid and urine.

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