scholarly journals Positive influence of aminosilanes on anti-EpCAM antibody immobilization on a glass surface

2021 ◽  
Vol 9 (2) ◽  
pp. 93-99
Author(s):  
Paula Kamińska ◽  
Karolina Buszka ◽  
Przemysław Pietras ◽  
Maciej Zabel ◽  
Michał Nowicki ◽  
...  
Keyword(s):  
Fluorescence Intensity ◽  
Glass Surface ◽  
Mean Fluorescence Intensity ◽  
Positive Influence ◽  
Contact Angles ◽  
Binding Activity ◽  
Antibody Immobilization ◽  
Glass Slides ◽  
The Mean ◽  
Detection Of Biomolecules

Abstract Immobilization of antibodies has a number of promising applications, including detection of biomolecules and cells. Well-oriented antibodies are required to bind them effectively. To eliminate the problem of random antibodies’ orientation, the surface of the device can be modified with silanes. This study aimed at elucidating if selected aminosilanes were able to bind antibodies in the appropriate orientation and thus retain their binding activity. Silanization of glass slides was performed using three amino-functional trialkoxysilanes – A, AE, and AEE. The immunofluorescent reaction was used to evaluate the potential of the silanized glass surface to bind anti-EpCAM antibodies. The affinity of selected anti-EpCAM HEA125 antibodies labeled with fluorochrome to tested silanized surfaces was evaluated by measuring the mean fluorescence intensity (MFI) in each analyzed area. The presented silanes effectively bound antibodies. Higher fluorescence intensity was noticed in the case of silane-coated glass slides in comparison to unmodified ones. The differences in the contact angles also confirmed this result. In the case of silane A, the fluorescence intensity reflected the amount of bound antibodies. However, there was no such a relation in the case of the silanes AE and AEE. Although our research gave promising results, the usefulness of selected silanes needs to be confirmed by further studies using cancer cells. Running title: Aminosilanes as enhancers of antibody immobilization

Expression of the cell adhesion molecules on leukocytes that demarginate during acute maximal exercise

1999 ◽  
Vol 86 (3) ◽  
pp. 970-976 ◽  
Author(s):  
Stephan F. van Eeden ◽  
John Granton ◽  
Jennifer M. Hards ◽  
Barbara Moore ◽  
James C. Hogg
Keyword(s):  
Fluorescence Intensity ◽  
Mean Fluorescence Intensity ◽  
Maximal Exercise ◽  
Flow Cytometric Analysis ◽  
Cycle Ergometer ◽  
Phenotypic Characteristics ◽  
Flow Cytometric ◽  
The Mean ◽  
Low Levels

The pulmonary vascular bed is an important reservoir for the marginated pool of leukocytes that can be mobilized by exercise or catecholamines. This study was designed to determine the phenotypic characteristics of leukocytes that are mobilized into the circulation during exercise. Twenty healthy volunteers performed incremental exercise to exhaustion [maximal O2consumption (V˙o2 max)] on a cycle ergometer. Blood was collected at baseline, at 3-min intervals during exercise, atV˙o2 max, and 30 min after exercise. Total white cell, polymorphonuclear leukocyte (PMN), and lymphocyte counts increased with exercise toV˙o2 max( P < 0.05). Flow cytometric analysis showed that the mean fluorescence intensity of L-selectin on PMN (from 14.9 ± 1 at baseline to 9.5 ± 1.6 atV˙o2 max, P < 0.05) and lymphocytes (from 11.7 ± 1.2 at baseline to 8 ± 0.8 atV˙o2 max, P < 0.05) decreased with exercise. Mean fluorescence intensity of CD11b on PMN increased with exercise (from 10.2 ± 0.6 at baseline to 25 ± 2.5 atV˙o2 max, P < 0.002) but remained unchanged on lymphocytes. Myeloperoxidase levels in PMN did not change with exercise. In vitro studies showed that neither catecholamines nor plasma collected atV˙o2 maxduring exercise changed leukocyte L-selectin or CD11b levels. We conclude that PMN released from the marginated pool during exercise express low levels of L-selectin and high levels of CD11b.

scholarly journals The Average IFN-γSecreting Capacity of Specific CD8+T Cells Is Compromised While Increasing Copies of a Single T Cell Epitope Encoded by DNA Vaccine

2012 ◽  
Vol 2012 ◽  
pp. 1-6
Author(s):  
Yanmin Wan ◽  
Jing Wang ◽  
Haizhu Zhou ◽  
Zhidong Hu ◽  
Xiaonan Ren ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
T Cell Receptor ◽  
Fluorescence Intensity ◽  
Cd8 T Cells ◽  
Mean Fluorescence Intensity ◽  
Cell Epitope ◽  
Cell Receptor ◽  
T Cell Epitope ◽  
The Mean

Previous studies suggested that both the frequency and the mean fluorescence intensity (MFI) of cytokine secreting T cells could be of great value for immunogenicity evaluation of a vaccine. In this study, by constructing epitope-based DNA vaccines encoding a previously identified CD8+T cell epitope, we investigated the influence of multiplying epitope copies on both the frequency and the MFI of specific IFN-γsecreting CD8+T cells. We found that frequencies of specific CD8+T cell could be improved by multiplying epitope copies, while the MFI of IFN-γsecreted by epitope-specific CD8+T cells decreased synchronously. And further analysis showed that the decrease of MFI was not caused by the functional avidity variation of CD8+T cell receptor.

Polycomb Group Protein BMI1 In Leukemia Development and Progression:Blocking the Cell Differentiation

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 2150-2150
Author(s):  
Hong-jie Shen ◽  
Xin Ding ◽  
Jian-nong Cen ◽  
Yuan-yuan Wang ◽  
Xiao-fei Qi ◽  
...  
Keyword(s):  
Fluorescence Intensity ◽  
Sodium Butyrate ◽  
Mean Fluorescence Intensity ◽  
Erythroid Differentiation ◽  
Mean Value ◽  
Polycomb Group ◽  
Myelogenous Leukemia ◽  
Transcriptional Level ◽  
Group Protein ◽  
The Mean

Abstract Abstract 2150 BMI1 is the most frequently altered PcG group protein observed in cancer and is useful in predicting prognosis as a biomarker in some malignant blood diseases including myelodysplastic syndromes (MDS) and chronic myelogenous leukemia (CML). However, the role and effect of BMI1 in these diseases is not clear. We have found that BMI1 expression in MDS CD34+ cells (n=13) was correlated with IPSS (R2=0.514,P=0.013). The MDS patient with overexpressed BMI1 shortly after diagnosis displayed a disease progression: one case of MDS-RA progressed to MDS-RAEB and two cases of MDS-RAEB transformed to AML, in company with more serious cytopenia in one or more lineages of bone marrow cells. A similar situation was found in CML. As the CML-CP patients (n=181) accelerated to CML-BP (n=27),the hemoglobin level as well as WBC and Plt counts markedly decreased (p<0.05), whereas the BMI1 transcriptional level in CML-BP (n=12) was much higher than that in CML-CP (n=26) detected by qRT-PCR (p<0.05). To further explore the role of BMI1 in malignant myeloid transformation, we cloned BMI1 cDNA ORF and transfected it into K562 by MSCV retroviral vector. The BMI1 protein expression in transfectant subclones was about three-folds of the untransfected control. NBT assay demonstrated that the differentiation induced by 20nm/L TPA for 72 hours in transfected cell were less than that in control cells. The percentage of NBT positive cells in K562, K562-MSCV, K562- BMI1SC1 and K562-BMI1SC2 were 51±7%, 60±8%, 27±6%, 33±7% (n=3), respectively. In addition, the immunophenotype of CD11b, CD13, CD15, CD33, CD34, CD64 and HLA-DR in TPA-treated cells detected by FCM found that only the mean fluorescence intensity of CD15 in transfected cells was obviously lower than that in control. The mean value of CD15 in K562, K562-MSCV, K562-BMI1SC1, K562-BMI1SC2 were 3.38, 3.25, 2.42, 2.54, respectively. The benzidine staining showed BMI1 transfected K562 treated by 40mm/L sodium butyrate for 72 hours had slower erythroid differentiation compared to that in control cells. The benzidine positive cell in K562, K562-MSCV, K562-BMI1SC1, K562-BMI1SC2 were 28±4%, 31±5%, 10±4%, 9±5% (n=3), respectively. We also found that the mean fluorescence intensity of GPA and CD71 were lower in BMI1 transfected cell compared to control after sodium butyrate treatment. The mean value of GPA in K562, K562-MSCV, K562-BMI1SC1, K562-BMI1SC2 were 36.4, 32.1, 20.6, 16.2 and the mean of CD71 were 3.07, 3.13, 2.8, 1.32, respectively. These in vitro results suggested that overexpression of BMI1 can inhibit cell myelomonocytoid and erythroid differentiation. In summary, we conclude that polycomb group BMI1 may contribute to clonal myeloid transformation by blocking multiple lineage differentiation and potentiating the stemness of the leukemia-initiating cells via possible epigenetic mechanisms. Disclosures: No relevant conflicts of interest to declare.

scholarly journals Acute exposure to paraquat affects the phenotypic differentiation of substantia nigra microglia in rats

2021 ◽  
Author(s):  
Wendi Zhang ◽  
Xiaobei Fan ◽  
Zhuo Fan ◽  
Bailin Wu ◽  
Mengchao Wang ◽  
...  
Keyword(s):  
Nervous System ◽  
Substantia Nigra ◽  
Western Blotting ◽  
Fluorescence Intensity ◽  
Mean Fluorescence Intensity ◽  
Early Stage ◽  
Exposure Dose ◽  
Phenotypic Differentiation ◽  
The Mean ◽  
Lung And Kidney

Abstract The toxicity of paraquat (PQ), a bipyridine cationic herbicide, to the lung and kidney has been widely recognized, but the acute toxic effects of PQ on the nervous system have received little attention. The aim of this study was to explore changes in the phenotypic differentiation of microglia in rats caused by acute PQ exposure. We found that acute PQ exposure induced pyknosis, edema and apoptosis in substantia nigra neurons. The results of immunohistochemistry and western blotting showed that the number of activated microglia increased, the number of microglia branches decreased and the length became shorter in the early stage of exposure to 25 mg/kg PQ. We then compared the mean fluorescence intensity of iNOS and ARG1. In the early stage of acute 25 mg/kg PQ exposure, the number of M1 phenotypes of microglia increased; in contrast, in the early stage of acute 45 mg/kg PQ exposure, the number of M2 phenotypes of microglia increased. On the 69th day, the expression of iNOS and ARG1 increased in the 25 mg/kg and 45 mg/kg PQ exposure groups. In sum, changes in microglia phenotypic differentiation were related to exposure dose and exposure time.

scholarly journals Sources of Variability in the Response of Labeled Microspheres and B Cells during the Analysis by a Flow Cytometer

2021 ◽  
Vol 22 (15) ◽  
pp. 8256
Author(s):  
Adolfas K. Gaigalas ◽  
Yu-Zhong Zhang ◽  
Linhua Tian ◽  
Lili Wang
Keyword(s):  
B Cells ◽  
Laser Beam ◽  
Cross Section ◽  
Mean Fluorescence Intensity ◽  
Numerical Aperture ◽  
Flow Cytometer ◽  
Fluorescence Signal ◽  
Minor Importance ◽  
Reliable Measure ◽  
The Mean

A stochastic model of the flow cytometer measurement process was developed to assess the nature of the observed coefficient of variation (CV%) of the mean fluorescence intensity (MFI) from a population of labeled microspheres (beads). Several sources of variability were considered: the total number of labels on a bead, the path through the laser beam, the optical absorption cross-section, the quantum yield, the numerical aperture of the collection optics, and the photoelectron conversion efficiency of the photomultiplier (PMT) cathode. The variation in the number of labels on a bead had the largest effect on the CV% of the MFI of the bead population. The variation in the path of the bead through the laser beam was minimized using flat-top lasers. The variability in the average optical properties of the labels was of minor importance for beads with sufficiently large number of labels. The application of the bead results to the measured CV% of labeled B cells indicated that the measured CV% was a reliable measure of the variability of antibodies bound per cell. With some modifications, the model can be extended to multicolor flow cytometers and to the study of CV% from cells with low fluorescence signal.

scholarly journals Electroflotation of cassiterite fines using a hydrophobic bacterium strain

2013 ◽  
Vol 66 (4) ◽  
pp. 507-512 ◽  
Author(s):  
Lorgio Gilberto Valdiviezo Gonzales ◽  
Gabriela Alejandra Huamán Pino ◽  
Maurício Leonardo Torem
Keyword(s):  
Current Density ◽  
Bubble Size ◽  
Mean Value ◽  
Contact Angles ◽  
Rhodococcus Opacus ◽  
Bacterial Concentration ◽  
Electrophoretic Mobilities ◽  
Potential Contact ◽  
Bacterium Strain ◽  
The Mean

In this work, the electroflotation of cassiterite fine ranges using Rhodococcus opacus (R. opacus) as bioreagent has been carried out. The interaction between R. opacus and mineral surface was valued through the zeta potential, contact angles measurements and adsorption studies. Furthermore, studies were attempted to check the effect of current density and microorganism concentration on mean bubble size (Sauter). After the interaction, the resulting particles exhibited hydrophobic characters, as verified by the increase of the contact angle. Also, the electrophoretic mobilities of cassiterite particles showed a mean value close to zero after interaction with R. opacus. The measurement of bubble size by laser diffraction showed a mean bubble size of 26µm. Current density and bacterial concentration seem to be the main parameters affecting the mean diameter of the bubbles. An electroflotation test reported recovery of around 64.5% at pH 5, concentration of 2.87x10¹² cells/ml (50 mg/L) and current density of 51.4 mA/cm².

scholarly journals ANALISIS FAKTOR-FAKTOR YANG MEMPENGARUHI IMPLEMENTASI ANGGARAN BERBASIS KINERJA

2019 ◽  
Vol 3 (3) ◽  
Author(s):  
Kaillin Lalli Randa ◽  
Ida Ayu Purba Riani ◽  
Balthazar Kreuta
Keyword(s):  
Data Analysis ◽  
Organizational Commitment ◽  
Positive Influence ◽  
Least Square ◽  
Ordinary Least Square ◽  
Average Value ◽  
Data Analysis Technique ◽  
Analysis Technique ◽  
Partial Analysis ◽  
The Mean

The purpose of the study was to analyze what factors influence the Performance Based Budget by using a sample of 87 respondents working at the Secretariat of the Papuan People's Representative Council. While the data analysis technique used is the Ordinary least square (OLS) technique. The results of the study are indicated by the calculation of the mean (mean) of 32 item questions and 87 respondents and the result is 137.31. If the value is compared to the criteria that the author has set, then the average value is included in the "Very Good" category. While the results of the partial analysis of organizational commitment (X1) have a significant and positive influence on the performance-based budget of 1,261. Keywords: Performance Based Budget

Potential Psychotropic Activity of Phlebotropic Drugs: Weak Interactions with Brain Benzodiazepine Receptors

1994 ◽  
Vol 9 (1) ◽  
pp. 32-36 ◽  
Author(s):  
W. Blätter ◽  
P. Schoch
Keyword(s):  
Weak Interactions ◽  
Benzodiazepine Receptors ◽  
Positive Influence ◽  
Binding Activity ◽  
Psychotropic Activity ◽  
Venous Disease ◽  
Receptor Binding Activity ◽  
Psychometric Studies ◽  
Organic Disorder

Background: Epidemiological and psychometric studies have provided evidence that some symptoms of venous disease might reflect a psychosomatic rather than organic disorder. Traditionally, plant extracts are prescribed to alleviate such symptoms. Since benzodiazepines (BZ) and BZ-like compounds are present in various plants, we studied potential interactions of ‘phlebotropic’ drugs with BZ receptors. Methods: Six drug preparations used in phlebology and extracts of hop and valerian were tested for neuronal and mitochondrial BZ receptor binding activity in vitro. In addition, plasma samples of volunteers who ingested phlebotropic drugs for 3 weeks were assayed for the presence of BZ-like activity. Results: All phlebotropic drug preparations interacted weakly with central and/or peripheral BZ receptors in vitro. Their diazepam-equivalent concentrations were, however, too low to be of pharmacological relevance. No binding activity was recovered in the blood of volunteers pretreated with phlebotropic drugs. Conclusion: The positive influence of so-called ‘phlebotropic’ drugs on the subjective symptoms of venous disease is not mediated through BZ receptors.

Fluorometric and Spectrophotometric Determination of Pirbuterol Hydrochloride in Authentic and Dosage Forms

1985 ◽  
Vol 68 (6) ◽  
pp. 1222-1225
Author(s):  
Mohamed E Mohamed ◽  
Hassan Y Aboul-Enein
Keyword(s):  
Potentiometric Titration ◽  
Alkaline Medium ◽  
Spectrophotometric Determination ◽  
Fluorescence Intensity ◽  
Perchloric Acid ◽  
Authentic Sample ◽  
Dosage Forms ◽  
Fluorometric Method ◽  
The Mean

Abstract Pirbuterol hydrochloride has been assayed in alkaline medium by using a fluorometric method to measure fluorescence intensity at 372 nm with excitation at 310 nm and by the ▵A method at 242 nm.The linearity ranges are 0.5-4 μg/mL and 10-50 μg/mL, respectively. An authentic pirbuterol HC1 sample was analyzed by nonaqueous potentiometric titration using 0.1N perchloric acid, and the results were compared with those for fluorometric and AA methods. The mean percent recoveries for the authentic sample were 98.72 ± 1.13 and 99.24 ± 0.85, respectively. When applied to commercial capsules containing 10 mg and 15 mg each, the fluorometric method gave mean percent recoveries of 101.11 ± 1.05 and 98.12 ± 0.93; the ▵A method gave mean percent recoveries of 100.57 ± 0.83 and 97.80 ± 0.75, respectively.

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