Kinetics of cell spreading in the presence of different concentrations of serum or fibronectin-depleted serum

1984 ◽  
Vol 71 (1) ◽  
pp. 51-59
Author(s):  
P. Knox

A morphometric assay has been used to show that speed of cell spreading is sensitive to the level of serum in the surrounding growth medium. There was an inverse relationship between serum concentration and speed of spreading; as serum concentration was increased from 0.1% to 100% cells took progressively longer to become fully spread. The time taken to achieve complete spreading in serum concentrations of 0.1, 1.0, 10 and 100% serum was 45, 60, 105 and 240 min, respectively. At serum concentrations of 3% and above, fibronectin depletion had no effect on rates of spreading. Only at concentrations below 3% was there an effect of fibronectin depletion and although cells became fully spread in the depleted serum they took longer to do so in comparison to native serum. It is suggested that plasma fibronectin plays no role in serum-stimulated spreading at serum concentrations of 3% and above since at these concentrations rates of spreading are identical whether fibronectin is present or not. At concentrations of 3% and above spreading is mediated by the 70K spreading factor. At serum concentrations below 3% both fibronectin and 70K factor are effective. The reason for the lack of effect of fibronectin at higher serum concentrations is an inhibition by albumin and other plasma proteins. In contrast, 70K factor is not affected by exogenous protein concentration. The effect of exogenous protein concentration on cell adhesion is discussed in terms of cell migration between compartments that have different extracellular protein concentrations.


Dermatology ◽  
2020 ◽  
pp. 1-7
Author(s):  
Aleksandra Batycka-Baran ◽  
Wojciech Baran ◽  
Danuta Nowicka-Suszko ◽  
Maria Koziol-Gałczyńska ◽  
Andrzej Bieniek ◽  
...  

<b><i>Background:</i></b> Hidradenitis suppurativa (HS) is a chronic inflammatory skin disease. An important role of innate immune dysregulation in the pathogenesis of HS has been highlighted. S100A7 (psoriasin) is an innate, antimicrobial protein that exerts proinflammatory and chemotactic action. <b><i>Objectives:</i></b> The objective of the study was to investigate serum concentrations of S100A7 in individuals with HS as compared to healthy controls. Further, we evaluated the expression of S100A7 in lesional HS skin as compared to perilesional (clinically uninvolved) HS skin and normal skin. <b><i>Methods:</i></b> Serum concentrations of S100A7 were evaluated with a commercially available ELISA kit. The expression of S100A7 in the skin was assessed using qRT-PCR and immunofluorescence staining. <b><i>Results:</i></b> We found increased expression of S100A7 in lesional HS skin as compared to perilesional HS skin (<i>p</i> = 0.0017). The expression of S100A7 in lesional HS skin was positively associated with serum C-reactive protein concentration and the severity of disease according to Hurley staging. The serum concentration of S100A7 in individuals with HS was decreased as compared to healthy controls and patients with psoriasis. <b><i>Conclusions:</i></b> Upregulated in lesional HS skin, S100A7 may enhance the inflammatory process and contribute to the HS pathogenesis.



1980 ◽  
Vol 46 (1) ◽  
pp. 97-112
Author(s):  
P. Knox ◽  
S. Griffiths

Sephacryl S-300 gel filtration of animal sera is used to demonstrate that there are at least 2 components that promote the ‘spreading’ of cells in culture. A morphometric technique is described to quantitate the spreading process. For a number of cell strains and established cell lines the more quantitatively significant spreading factor is not fibronectin. Rather it is a component with fibronectin and seems to cause spreading via a different mechanism from that stimulated by fibronectin. Thus fibronectin will cause spreading in the absence of protein synthesis, whereas the smaller component requires protein synthesis. The kinetics of spreading are also different at all concentrations of the factors that are effective. By comparing the spreading promoted by whole sera with that promoted by separate serum fractions following chromatography we conclude that under normal conditions plasma fibronectin plays little part in initial cell spreading. This view is supported by the fact that fibronectin-depleted serum will stimulate cell spreading.



1975 ◽  
Vol 48 (3) ◽  
pp. 231-233
Author(s):  
P. Dandona ◽  
D. J. El Kabir ◽  
F. Naftolin ◽  
P. C. B. MacKinnon

1. The effect of long-acting thyroid stimulator (LATS) on the serum luteinizing hormone (LH) levels of the rat in pro-oestrus has been studied. 2. The injection of three out of four LATS-containing immunoglobulin G fractions caused an increase in amounts of serum LH. 3. Adrenalectomy and dexamethasone suppression did not alter this response. 4. Injection of large doses of adrenocorticotrophic hormone did not produce any increase in serum concentrations of LH. 5. It is postulated that LATS may have a direct effect on the release of LH from the pituitary gland.



2019 ◽  
Vol 54 (4) ◽  
pp. 233-240
Author(s):  
Agnieszka Olejnik ◽  
Iwona Bil-Lula ◽  
Anna Krzywonos-Zawadzka ◽  
Łukasz Kozera

Background: Adipose tissue has been recognized as an endocrine organ of considerable complexity, able to secrete adipose-derived factors named adipokines. The secretion of adipokines depends greatly on the volume of body fat, which in turn significantly changes their activity towards a diabetogenic, proinflammatory, and atherogenic pattern. One of the discovered adipokines is dipeptidyl peptidase 4 (DPP4).<br>Objectives: The aim of this preliminary study was to establish an association between serum concentration of DPP4 and obesity at early stage.<br>Material and methods: A total of 32 obese adult volunteers and 40 lean controls were studied. Total cholesterol, triglycerides, HDL (high-density lipoprotein), LDL (low-density lipoprotein) and glucose concentrations were assessed in serum/plasma samples by using commercial tests. Body mass index (BMI) and waist-hip ratio (WHR) were determined. Serum concentrations of DPP4, leptin, visfatin, CRP (C-reactive protein), and TNF-alpha (tumor necrosis factor alpha) were measured using commercial ELISA immunoassay tests.<br>Results: Serum concentrations of DPP4, leptin and visfatin were significantly higher in obese than in lean subjects. The concentration of DPP4 positively correlated with BMI and body mass. Serum CRP and TNF-alpha were increased in obese compared to non-obese, and had a positive correlation with BMI, WHR and body mass.<br>Conclusions: We showed that there is an association between the DPP4, leptin and visfatin concentration in serum and elevated body weight and BMI even at early stage of obesity (I stage of obesity). It suggest the importance of adipose tissue reduction to prevent rise of adipokines levels and further negative metabolic and inflammatory changes.



1924 ◽  
Vol 39 (6) ◽  
pp. 921-929 ◽  
Author(s):  
G. C. Linder ◽  
C. Lundsgaard ◽  
D. D. Van Slyke ◽  
E. Stillman

1. We have not observed gross increases in plasma volume in glomerulonephritis, nephrosis, or nephrosclerosis, even when the concentration of plasma proteins was much below normal. Our results indicate the probability that "hydremic plethora" does not occur. 2. The low protein concentration frequently observed in the plasma in nephritis is not due to increased plasma volume but to a decrease of the total amount of plasma protein in the body. 3. Changes in plasma volume showed no constant relationship to changes in edema.



1985 ◽  
Vol 227 (2) ◽  
pp. 439-455 ◽  
Author(s):  
P M Bayley ◽  
F M M Butler ◽  
D C Clark ◽  
E J Manser ◽  
S R Martin

The kinetics of assembly were studied for bovine and pig microtubule protein in vitro over a range of conditions of pH, temperature, nucleotide and protein concentration. The kinetics are in general biphasic with two major processes of similar amplitude but separated in rate by one order of magnitude. Rates and amplitudes are complex functions of solution conditions. The rates of the fast phase and the slow phase attain limiting values as a function of increasing protein concentration, and are more stringently limited at pH 6.5 than pH 6.95. Such behaviour indicates that mechanisms other than the condensation polymerization of tubulin dimer become rate-limiting at higher protein concentration. The constancy of the wavelength-dependence of light-scattering and ultrastructural criteria indicate that microtubules of normal morphology are formed in both phases of the assembly process. Electrophoretic analysis of assembling microtubule protein shows that MAP- (microtubule-associated-protein-)rich microtubules are formed during the fast phase. The rate of dissociation of oligomeric species on dilution of microtubule protein closely parallels the fast-phase rate in magnitude and temperature-dependence. We propose that the rate of this process constitutes an upper limit to the rate of the fast phase of assembly. The kinetics of redistribution of MAPs from MAP-rich microtubules may be a factor limiting the slow-phase rate. A working model is derived for the self-assembly of microtubule protein incorporating the dissociation and redistribution mechanisms that impose upper limits to the rates of assembly attainable by bimolecular addition reactions. Key roles are assigned to MAP-containing fragments in both phases of microtubule elongation. Variations in kinetic behaviour with solution conditions are inferred to derive from the nature and properties of fragments formed from oligomeric species after the rapid temperature jump. The model accounts for the limiting rate behaviour and indicates experimental criteria to be applied in evaluating the relative contributions of alternative pathways.



2020 ◽  
Vol 9 (8) ◽  
pp. e347985005
Author(s):  
Alexandre Bernardi ◽  
Antonio Waldimir Leopoldino da Silva ◽  
Catia Capeletto ◽  
Felipe Junior Portela da Silva ◽  
Renata Cristina Defiltro ◽  
...  

This study compared the effects of unchopped and chopped hay on milk production and composition, feed digestibility, and physiology of Lacaune sheep. Eighteen ewes were stratified by parity (two or three), days of lactation (60 ± 3.7 days), and milk production (1.04 L/ewe/day), and were randomly assigned to 1 of 2 treatments: 1) Unchopped or 2) Chopped Tifton 85 hay. Corn silage and concentrate were also provided. Chopped hay ewes gave lower (P≤0.01) dry matter intake and greater (P=0.02) crude protein digestibility. No effects of treatment were detected (P≥0.38) for the digestibility of dry matter, or of neutral and acid detergent fibers. Chopped hay ewes had greater (P≤0.01) milk production (d 7 and d 12), lactation persistence, and feed efficiency. Ewes eating chopped hay had greater (P=0.03) protein concentration in their milk. However, there were no effects of treatment × day and treatments (P≥0.16) for concentrations of fat, lactose, minerals, deffated dry extract, or density. Ewes eating chopped hay presented lower (P<0.01) serum concentrations of urea and tended to have lower (P=0.10) serum concentrations of glucose only on d 12. However, there were no effects of treatment × day and treatments (P≥0.16) for serum concentrations of total protein, albumin, globulin, triglycerides, or cholesterol. These data suggest that chopped hay promotes lower dry matter intake and serum concentrations of glucose and urea, but improves milk production, lactation persistence, feed efficiency, and protein concentration.



2014 ◽  
Vol 19 (3) ◽  
pp. 182-188
Author(s):  
Lea S. Eiland ◽  
Kalyani B. Sonawane

OBJECTIVES: With an increase in vancomycin resistance and the prevalence of obesity in children, alterations of vancomycin dosing regimens may be necessary to achieve target serum concentrations. The primary objective of this study was to describe initial vancomycin dosing with resulting serum concentrations in healthy-weight and overweight/obese children. Secondary objectives include comparing vancomycin dosing regimens of healthy-weight and overweight/obese patients that produced target trough serum concentrations and evaluating the likelihood of attaining target concentrations by patient characteristics. METHODS: This retrospective review evaluated healthy-weight and overweight/obese patients, aged 2 to 18 years, who had vancomycin trough serum concentrations obtained between 2005 and 2010. Vancomycin dosing, initial trough serum concentrations, pharmacokinetic parameters, and patient demographics were collected for analysis. Target trough serum concentrations were defined as 10 to 20 mg/L. RESULTS: The study included 98 patients (48 healthy weight, 50 overweight/obese) of which only 14 patients (14.2%, 6 healthy weight, 8 obese) reached a target trough serum concentration with empiric dosing. No difference was found between the mean daily dosing of vancomycin that produced target trough serum concentrations in healthy-weight or overweight/obese patients (53.63 mg/kg/day vs 51.6 mg/kg/day, respectively). Demographic or clinical characteristics were not found to be associated with the likelihood of target trough serum concentration attainment. CONCLUSIONS: Vancomycin dosing in healthy-weight and overweight/obese pediatric patients did not reach target trough serum concentrations most of the time. In obtaining initial target serum concentrations, no dosing difference was identified for overweight/obese patients compared with healthy-weight patients. Alternate dosing strategies, therapeutic monitoring, and clinical outcomes should continue to be evaluated in this population.



2021 ◽  
Vol 38 (5) ◽  
pp. 115-122
Author(s):  
Kazim G. Gasanov ◽  
Viktor A. Zurnadzhyants ◽  
Eldar A. Kchibekov ◽  
M. I. Shikhragimov

Objective. To determine the blood serum 2-microglobulin and 2-macroglobulin concentration in patients undergoing renal replacement therapy (programmed hemodialysis) for the diagnosis of uremic pancreatitis and / or destructive pancreatitis. Materials and methods. The study involved 52 patients admitted to the Surgical Unit of Astrakhan "RZhD-Medicine" Hospital and City Clinical Hospital № 3. The blood serum 2-microglobulin and 2-macroglobulin concentration was analyzed in patients admitted on an emergency basis with suspicion of uremic pancreatitis and destructive pancreatitis, who receive renal replacement therapy (programmed hemodialysis). The control group included 50 outpatients undergoing renal replacement therapy (programmed hemodialysis). The study did not include patients with suspected pancreatitis who were not receiving renal replacement therapy. The period of the study is 20192021. Results. The concentration of blood serum 2-microglobulin is statistically higher than normal in all patients, who had received renal replacement therapy (programmed hemodialysis) in anamnesis. The most statistically high concentration of 2-microglobulin was revealed while studying patients with uremic pancreatitis (n = 34), and was (30.0 2.75 mg/l) compared with the blood serum concentration in patients with destructive pancreatitis (8 0.51 mg / l). The concentration of 2-macroglobulin was statistically lower in destructive pancreatitis (n = 18) and was 615 161 mg/l compared with uremic pancreatitis (980 216 mg/l). In the control group of outpatients (n = 50) receiving renal replacement therapy (programmed hemodialysis), no statistically significant blood serum concentrations of 2-microglobulin and 2-macroglobulin were found. Conclusions. A clear dependence of the concentration of 2-microglobulin and 2-macroglobulin on the severity of uremic pancreatitis and destructive pancreatitis was established. Statistically high values of 2-microglobulin concentrations were obtained in patients with uremic pancreatitis, and the 2-macroglobulin level was statistically low in destructive pancreatitis.



2020 ◽  
Vol 73 (2) ◽  
pp. 316-320
Author(s):  
Alexandr E. Abaturov ◽  
Olena O. Rusakova

The aim: To determine the most informative immunological and molecular genetic factors which reflect the characteristics of the inflammatory process and make it possible to predict the development of bronchial obstruction during acute bronchitis in infants. Materials and methods: 120 children aged from 6 months to 3 years old with acute bronchitis were examined. We determined NF-κB expression level in peripheral blood lymphocytes by flow cytometry method, the serum concentrations of interferon-γ, interleukins 4, 12 and 13 by ELISA, total IgE serum level by ECLIA and calculated the relative risk (RR) for each of these parameters. Results: The risk of bronchial obstruction development was high when the relative number of lymphocytes expressing NF-κB was under 49.8% (RR=3.27, 95% CI=2.09-4.92). IL-12 serum concentration from 41.35 pg/ml to 173.06 pg/ml (RR=5.35, 95% CI=2.82-9.15) and IL-13 serum concentration from 4.06 pg/ml to 6.71 pg/ml (RR=4.0, 95% CI=2.39-6.41) were early predictors of the appearance of wheezing during the disease. The probability of the development of bronchial obstruction was low when the relative number of lymphocytes expressing NF-κB was above 49.8% (RR=0.40, 95% CI=0.28-0.62). NF-κB expression level above 0.91 Units (RR=0.20, 95% CI=0.11-0.39), serum concentrations of IFN-γ above 9.83 pg/ml (RR=0.50, 95% CI=0.31-0.81), IL-12 above 173.06 pg/ml (RR=0.49, 95% CI=0.30-0.82), IL-13 above 6.71 pg/ml (RR=0.40, 95% CI=0.22-0.72) reduced the probability of the appearance of wheezing significantly. Conclusions: The development of bronchial obstruction during acute bronchitis in infants is associated with the relatively low NF-κB and IL-12 levels, imbalance in IFN-γ and IL-13 production.



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