AN ACCURATE METHOD FOR THE ESTIMATION OF LOW CONCENTRATIONS OF DEXTRAN IN PLASMA

1957 ◽  
Vol 35 (6) ◽  
pp. 383-390 ◽  
Author(s):  
Robert E. Semple
Keyword(s):  
Aqueous Extract ◽  
Accurate Method ◽  
Protein Precipitation ◽  
In Vitro Tests ◽  
Plasma Samples ◽  
Carbohydrate Concentration ◽  
Low Concentrations ◽  
Standard Deviations

A method is presented for the determination in plasma of small (50–150 mg./100 ml.) amounts of dextran. The procedure, which requires between 3 and 4 hours, consists of protein precipitation, glucose removal by dialysis, and the determination of the carbohydrate concentration of the resulting aqueous extract by a modified anthrone technique. Results of in vitro tests show that average dextran recovery is essentially 100% and that standard deviations in recovery range from 1.7 to 2.5% depending upon the dextran concentration. Deviations are reduced to a range of 1.4–1.7% by the use of duplicate plasma samples.

AN ACCURATE METHOD FOR THE ESTIMATION OF LOW CONCENTRATIONS OF DEXTRAN IN PLASMA

1957 ◽  
Vol 35 (1) ◽  
pp. 383-390
Author(s):  
Robert E. Semple
Keyword(s):  
Aqueous Extract ◽  
Accurate Method ◽  
Protein Precipitation ◽  
In Vitro Tests ◽  
Plasma Samples ◽  
Carbohydrate Concentration ◽  
Low Concentrations ◽  
Standard Deviations

A method is presented for the determination in plasma of small (50–150 mg./100 ml.) amounts of dextran. The procedure, which requires between 3 and 4 hours, consists of protein precipitation, glucose removal by dialysis, and the determination of the carbohydrate concentration of the resulting aqueous extract by a modified anthrone technique. Results of in vitro tests show that average dextran recovery is essentially 100% and that standard deviations in recovery range from 1.7 to 2.5% depending upon the dextran concentration. Deviations are reduced to a range of 1.4–1.7% by the use of duplicate plasma samples.

Development of an HPLC-UV Method for Quantification of Stattic

2019 ◽  
Vol 15 (6) ◽  
pp. 568-573
Author(s):  
Soheil Sedaghat ◽  
Ommoleila Molavi ◽  
Akram Faridi ◽  
Ali Shayanfar ◽  
Mohammad Reza Rashidi
Keyword(s):  
High Performance ◽  
Accurate Method ◽  
Plasma Samples ◽  
Promising Target ◽  
Relative Standard ◽  
Dimerization Inhibitor ◽  
Oncogenic Protein ◽  
First Time ◽  
Transcription 3

Background: Signal transducer and activator of transcription 3 (STAT3), an oncogenic protein found constitutively active in many types of human malignancies, is considered to be a promising target for cancer therapy. Objective: In this study for the first time, a simple and accurate method has been developed for the determination of a STAT3 dimerization inhibitor called stattic in aqueous and plasma samples. Methods: A reverse-phase high-performance liquid chromatography (RP-HPLC) composed of C18 column as stationary phase, and the mixture of acetonitrile (60%) and water (40%) as mobile phase with a UV detection at 215 nm were applied for quantification of stattic. The developed method was validated by Food and Drug Administration (FDA) guideline. Results: The method provided a linear range between 1-40 and 2.5-40 µg mL-1 for aqueous and plasma samples, respectively, with a correlation coefficient of 0.999. The accuracy (as recovery) of the developed method was found to be between 95-105% for aqueous medium and 85-115% for plasma samples. The precision (as relative standard deviation) for aqueous and plasma samples was less than 6% and 15%, respectively. The sensitivity of the developed method based on FDA guideline was 1 µg mL-1 for aqueous and 2.5 µg mL-1 for plasma samples. Conclusion: These results show that the established method is a fast and accurate quantification for stattic in aqueous and plasma samples.

scholarly journals Comparative Characteristics of Determination of Antioxidant Activity of Sea Buckthorn Fruits by Various Methods

2019 ◽  
Vol 8 (4) ◽  
pp. 48-52
Author(s):  
O. V. Trineeva
Keyword(s):  
Antioxidant Activity ◽  
Medicinal Plant ◽  
Plant Material ◽  
Natural Antioxidants ◽  
Sea Buckthorn ◽  
In Vitro Tests ◽  
Medicinal Plant Material

Introduction. Recently, much attention has been paid to the primary assessment of the pharmacological effect of various drugs using in vivo and in vitro tests. It is known that such a medicinal plant as sea buckthorn, in its phytochemical composition is rich in natural antioxidants: carotenoids, tocopherols, flavonoids, ascorbic acid, etc. In some publications there is information about the antioxidant activity of sea buckthorn and fatty oil based on them. However, information on the comparative characteristics of the use of various methods for determining the antioxidant activity of this type of medicinal plant material and the results obtained are not found in the scientific literature.Aim. The aim of this work was a comparative determination of the antioxidant activity of medicinal plant material of buckthorn fruits of various species of buckthorn.Materials and methods. The total antioxidant activity of water and water-alcohol extracts from the fruits of sea buckthorn fruits was determined using various techniques recommended in the literature. The antioxidant activity of the extracts was determined by permanganometric titration, in vitro inhibition of adrenaline autooxidation, and also in a biological model, Parametium caudatum cell culture.Results and discussion. The effect of the extractant polarity on the value of antioxidant activity was studied. It was found that the highest content of antioxidants in the extraction is observed when using 96 % ethanol as an extractant.Conclusion. Using three methods, the prospects of using sea buckthorn fruits and preparations based on them as a source of antioxidants are shown. 

In vitro determination of prebiotic potential of aqueous extract of horse chestnut by-product

2019 ◽  
Vol 19 ◽  
pp. 100190
Author(s):  
Joanna Przyborska ◽  
Michael C. Hall ◽  
Mary Concannon
Keyword(s):  
Aqueous Extract ◽  
Horse Chestnut

scholarly journals Validation by isoelectric focusing of the anion-exchange isotransferrin fractionation step involved in determination of carbohydrate-deficient transferrin by the CDTect assay

1998 ◽  
Vol 44 (1) ◽  
pp. 27-34 ◽  
Author(s):  
Torsten Arndt ◽  
Rolf Hackler ◽  
Tilman O Kleine ◽  
Axel M Gressner
Keyword(s):  
Isoelectric Focusing ◽  
Laboratory Diagnosis ◽  
Good Precision ◽  
Chronic Alcohol Abuse ◽  
Negative Results ◽  
Iron Saturation ◽  
Low Concentrations ◽  
Carbohydrate Deficient Transferrin

Abstract Serum concentration of carbohydrate-deficient transferrin (CDT) is used for laboratory diagnosis of chronic alcohol abuse. Using isoelectric focusing for validation of the initial isotransferrin fractionation step involved in the determination of CDT by the CDTect assay, we found a complete in vitro iron saturation of transferrin and sufficient stability of the transferrin iron load during column passage; effective separation of non-CDT-isotransferrins and CDT-isotransferrins at the microcolumns; partial coelution of trisialo-Fe2-transferrin, which did not significantly affect CDT measurement; partial retention of CDT-isotransferrins, especially disialo-Fe2-transferrin, which may cause falsely negative results for CDT at the upper reference limits; good precision of the isotransferrin fractionation step; and no significant effects of low concentrations of serum protein and transferrin. We strongly urge standardization of CDT analysis and suggest isoelectric focusing for validation of CDT analysis methods and verification of odd results.

Determination of anti-Müllerian hormone concentrations in blood as a tool to select Holstein donor cows for embryo production: from the laboratory to the farm

2012 ◽  
Vol 24 (7) ◽  
pp. 932 ◽  
Author(s):  
Charlène Rico ◽  
Laurence Drouilhet ◽  
Pascal Salvetti ◽  
Rozenn Dalbiès-Tran ◽  
Peggy Jarrier ◽  
...  
Keyword(s):  
Embryo Transfer ◽  
Plasma Samples ◽  
In Vitro Production ◽  
Experimental Station ◽  
Multiple Ovulation ◽  
Practical Information ◽  
Vitro Production ◽  
Donor Cows

High between-animal variability in the number of embryos produced by multiple ovulation and embryo transfer (MOET) and ovum pick-up and in vitro production (OPU–IVP) methods remains a major limit to the development of embryo biotechnologies in cattle. The measurement of anti-Müllerian hormone (AMH) endocrine concentrations in cows can help to predict their follicular and ovulatory responses to gonadotrophin treatment. The present study aimed to provide practical information for a simple prognostic method based on AMH measurement in Holstein cows. Accurate AMH concentrations could be measured with ELISA in blood or plasma. In cows undergoing repeated OPU protocols over 1 year, the AMH concentrations measured in plasma samples collected before each gonadotrophin treatment were found to be highly repeatable and were tightly correlated with follicular responses. From data obtained at both an experimental station and farm settings, it was possible to propose AMH cut-off values to identify low-responding cows. Gonadotrophin-stimulated cows producing fewer than 15 large follicles at oestrus and fewer than 10 embryos in MOET protocols could be discarded efficiently with plasma AMH concentrations below 87 and 74 pg mL–1, respectively. In conclusion, we propose a prognostic method based on a single AMH measurement to improve the results of embryo biotechnologies.

scholarly journals Formulation of Improved Traditional Drugs against virulent species of Salmonella spp in Benin: assessment of the properties from Uvaria chamae, Lantana camara and Phyllantus amarus in Benin, West Africa

2019 ◽  
Author(s):  
Boris LEGBA ◽  
Victorien DOUGNON ◽  
Carène GBAGUIDI ◽  
Alidah ANIAMBOSSOU ◽  
Esther DEGUENON ◽  
...  
Keyword(s):  
Aqueous Extract ◽  
Bacterial Load ◽  
Scientific Data ◽  
Lantana Camara ◽  
Toxicity Tests ◽  
In Vitro Tests ◽  
Post Inoculation ◽  
Salmonella Spp

Abstract Background Uvaria chamae (Annonaceae), Phyllantus amarus (Phyllantaceae) and Lantana camara (Verbenaceae) are empirically alleged to be used as Beninese medicinal plants in the treatment of salmonellosis. This study aimed to produce scientific data on in vitro and in vivo efficacy of Uvaria chamae, Lantana camara and Phyllantus amarus on multiresistant Salmonella spp isolated in Benin.Results After in vitro tests on aqueous and ethanolic extracts of Uvaria chamae, Lantana camara and Phyllantus amarus , only the aqueous extract of Uvaria chamae (leaves) showed the best anti- Salmonella ’s activity. It has been used for the following experiments. The induction of salmonellosis revealed 9.0 10 8 CFU/ml was optimal concentration for triggering and maintaining the symptoms in chicks. This infective concentration has been used for in vivo assessment. 24 hours post inoculation later, the symptoms of salmonellosis (wet cloaca, diarrhea stool and somnolence) were observed in infected groups. After seven days of treatment, the rate of reduction of bacterial load at 100 mg / L, 200 mg / L, 400 mg / L of this extract was 85%, 52.38% and 98% respectively in the chicks groups infected with Salmonella Typhimurium ATCC 14028. About the groups infected with Salmonella spp (virulent strain), the rate of reduction of bacterial load at 100 mg / L, 200 mg / L, 400 mg / L of this extract was 0%, 98.66% and 99.33%. The toxicity tests did not show any significant effect of the Uvaria chamae ’s extract on the biochemical and hematological parameters of the chicks.Conclusion The aqueous extract of Uvaria chamae is active in vitro and in vivo on multiresistant strains of Salmonella spp . This plant is a good candidate for the development of an improved traditional medicine for the management of salmonellosis.

scholarly journals Wound Healing Activity of α-Pinene and α-Phellandrene

Molecules ◽  
2021 ◽  
Vol 26 (9) ◽  
pp. 2488
Author(s):  
Judith Salas-Oropeza ◽  
Manuel Jimenez-Estrada ◽  
Armando Perez-Torres ◽  
Andres Eliu Castell-Rodriguez ◽  
Rodolfo Becerril-Millan ◽  
...  
Keyword(s):  
Wound Healing ◽  
Healing Process ◽  
Folk Medicine ◽  
Fibroblast Cell ◽  
In Vitro Tests ◽  
Low Concentrations ◽  
In Vivo Tests ◽  
Wound Healing Activity

Bursera morelensis is used in Mexican folk medicine to treat wounds on the skin. Recently, it was shown that the essential oil (EO) of B. morelensis has wound healing activity, accelerating cutaneous wound closure and generating scars with good tensile strength. α-pinene (PIN) and α-phellandrene (FEL) are terpenes that have been found in this EO, and it has been shown in different studies that both have anti-inflammatory activity. The aim of this study was to determine the wound healing activity of these two terpenes. The results of in vitro tests demonstrate that PIN and FEL are not cytotoxic at low concentrations and that they do not stimulate fibroblast cell proliferation. In vivo tests showed that the terpenes produce stress-resistant scars and accelerate wound contraction, due to collagen deposition from the early stages, in wounds treated with both terpenes. Therefore, we conclude that both α-pinene and α-phellandrene promote the healing process; this confirms the healing activity of the EO of B. morelensis, since having these terpenes as part of its chemical composition explains part of its demonstrated activity.

Interlaboratory evaluation of four RIA kits for determination of plasma cortisol, with special reference to accuracy: influence of matrix in calibration standards.

1980 ◽  
Vol 26 (13) ◽  
pp. 1899-1902 ◽  
Author(s):  
O Lantto ◽  
I Björkhem ◽  
R Blomstrand ◽  
A Kallner
Keyword(s):  
Mass Spectrometry ◽  
Isotope Dilution ◽  
Plasma Cortisol ◽  
Isotope Dilution Mass Spectrometry ◽  
Accurate Method ◽  
Comparison Method ◽  
Plasma Samples ◽  
Normal Range ◽  
Calibration Standards

Abstract We used four RIA kits for determination of plasma cortisol to assay 12 plasma samples in four laboratories, and compared the results with those obtained with a highly accurate method based on isotope dilution/mass spectrometry. All kits (Farmos, NEN, Sorin, and Clinical Assays) showed 10-50% deviation from the comparison method in the normal range (200-700 nmol/L). The inter- and intralaboratory imprecision (CV) ranged between 8-27% and 5-11%, respectively. Possible explanations for this low accuracy are discussed. Retention of an intact biological matrix in the calibration standards seems to be one prerequisite for accuracy.

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