Apparent absence of symmetrical transcription in Tetrahymena mitochondria

Transcription in Tetrahymena pyriformis mitochondria has been examined for whether or not symmetrical transcription occurs. A ribonuclease A digestion in high-ionic strength was used as a test for the presence of double-stranded RNA (dsRNA) either before or after self-annealing- This test was applied to RNA prepared using pulse lengths of from 1 to 30 min. If symmetrical transcription occurred, then the amount of dsRNA should have varied inversely with pulse length. There was no evidence for the presence of dsRNA other than a ribonuclease-resistant core. A search was also made among the largest transcripts present (> 26S) since this region of a sucrose gradient is enriched in symmetrical transcripts in HeLa cells. Again none were found. In order to allow for possible rapid processing as the reason for the failure to find dsRNA, total cellular RNA was extracted as quickly as possible, and the ribonuclease digest analyzed by Sephadex chromatography. No large pieces of dsRNA were found.

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THE RELATIVE DISTRIBUTION OF THYROXINE, TRIIODOTHYRONINE AND 3,3′,5′-(REVERSE)-TRIIODOTHYRONINE IN VARIOUS FRACTIONS OF THYROGLOBULIN

Acta Endocrinologica ◽

10.1530/acta.0.0880298 ◽

1978 ◽

Vol 88 (2) ◽

pp. 298-305 ◽

Cited By ~ 2

Author(s):

Peter Laurberg

Keyword(s):

Ionic Strength ◽

Guinea Pig ◽

Sucrose Gradient ◽

Deae Cellulose ◽

High Ionic Strength ◽

Relative Distribution ◽

Thyroid Extract ◽

Reverse Triiodothyronine ◽

Thyroid Secretion ◽

Stable Iodine

ABSTRACT Thyroglobulin fractions rich and poor in new thyroglobulin were separated by means of DEAE-cellulose chromatography of dog thyroid extracts and by zonal ultracentrifugation in a sucrose gradient of guinea pig thyroid extract incubated at low temperature. The distribution of thyroxine, triiodothyronine and 3,3′,5′-(reverse)-triiodothyronine in hydrolysates of the different fractions was estimated by radioimmunoassays. Following DEAE-cellulose chromatography there was a small but statistically significant increase in the T4/T3 ratio in thyroglobulin fractions eluted at high ionic strength - that is fractions relatively rich in stable iodine but poor in fresh thyroglobulin. There were no differences in the T4/rT3 ratios between the different fractions. The ratios between iodothyronines were almost identical in the various thyroglobulin fractions following zonal ultracentrifugation in a sucrose gradient of cold treated guinea pig thyroid extract. These findings lend no support to the possibility that a relatively high content of triiodothyronines in freshly synthesized thyroglobulin modulates the thyroid secretion towards a preferential secretion of triiodothyronine and 3,3′,5′-(reverse)-triiodothyronine at the expense of the secretion of thyroxine.

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Chromatographic Separation, and Characteristics of Nucleic Acids from HeLa Cells

The Journal of General Physiology ◽

10.1085/jgp.44.5.899 ◽

1961 ◽

Vol 44 (5) ◽

pp. 899-910 ◽

Cited By ~ 45

Author(s):

Lennart Philipson

Keyword(s):

Sodium Chloride ◽

Ionic Strength ◽

Bovine Serum Albumin ◽

Nucleic Acids ◽

Hela Cells ◽

Sedimentation Coefficient ◽

High Ionic Strength ◽

Salt Gradient ◽

Low Ionic Strength ◽

Phenol Extract

The application of the phenol-duponol method to extraction of nucleic acids from HeLa cells is described. Chromatography of the phenol extract on an esterified bovine serum albumin column with a salt gradient of sodium chloride gives separation of soluble RNA, DNA, and two different high molecular RNA fractions. Ultracentrifugation of the DNA eluted from the column gives a sedimentation coefficient (s20o,w) of 38, which agrees with ultracentrifugation data on the phenol extract. The eluted RNA appears polydisperse at low ionic strength, but at high ionic strength and after alcohol precipitation two fractions with the sedimentation coefficients of 16 and 25 to 29, respectively, were obtained.

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Importance of Protease Inhibition in Studies on Purified Factor VIII (Antihaemophilic Factor)

Thrombosis and Haemostasis ◽

10.1055/s-0038-1647943 ◽

1976 ◽

Vol 35 (01) ◽

pp. 186-190 ◽

Cited By ~ 6

Author(s):

Eugen A. Beck ◽

Peter Bachmann ◽

Peter Barbier ◽

Miha Furlan

Keyword(s):

Ionic Strength ◽

Factor Viii ◽

Gel Filtration ◽

High Ionic Strength ◽

Procoagulant Activity ◽

Carrier Protein ◽

Protease Inhibition ◽

Functional Sites ◽

Molecular Weight Peak ◽

Von Willebrand

SummaryAccording to some authors factor VIII procoagulant activity may be dissociable from carrier protein (MW~ 2 × 106) by agarose gel filtration, e.g. at high ionic strength. We were able to reproduce this phenomenon. However, addition of protease inhibitor (Trasylol) prevented the appearance of low molecular weight peak of factor VIII procoagulant activity both at high ionic strength and elevated temperature (37°C). We conclude from our results that procoagulant activity and carrier protein (von Willebrand factor, factor VIII antigen) are closely associated functional sites of native factor VIII macro molecule. Consequently, proteolytic degradation should be avoided in functional and structural studies on factor VIII and especially in preparing factor VIII concentrate for therapeutic use.

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Kaolin based protective barrier in municipal landfills against adverse chemo-mechanical loadings

Scientific Reports ◽

10.1038/s41598-021-89787-z ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Partha Das ◽

Tadikonda Venkata Bharat

Keyword(s):

Ionic Strength ◽

High Ionic Strength ◽

The Self ◽

Design Parameters ◽

Layered System ◽

Geosynthetic Clay Liners ◽

Clay Liners ◽

Landfill Liner ◽

First Time ◽

Applied Stresses

AbstractIn this work, we assess the self-sealing and swelling ability of the compacted granular bentonite (GB) under an inorganic salt environment and induced overburden stresses from the landfill waste. The laboratory permeation tests with high ionic strength salt solutions reveal that the GB fails to seal and exhibits a significant mechanical collapse under different applied stresses. The applicability of GB in the form of geosynthetic clay liners as the bottom liner facilities in landfills that produce high ionic strength salt leachates, therefore, remains a serious concern. We propose an additional barrier system based on kaolin, for the first time, to address this problem. The proposed kaolin-GB layered system performs satisfactorily in terms of its sealing and swelling ability even in adverse saline conditions and low overburden stresses. The kaolin improves the osmotic efficiency of the self and also helps the underlying GB layer to seal the inter-granular voids. The estimated design parameters by through-diffusion test suggest that the kaolin-GB layered system effectively attenuates the permeant flux and suitable as a landfill liner.

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High ionic strength dissociation assay (HISDA) for high drug tolerant immunogenicity testing

Bioanalysis ◽

10.4155/bio-2020-0138 ◽

2020 ◽

Author(s):

Gregor Jordan ◽

Alexander Pöhler ◽

Florence Guilhot ◽

Meike Zaspel ◽

Roland F Staack

Keyword(s):

Ionic Strength ◽

Acid Treatment ◽

Structural Integrity ◽

Drug Tolerance ◽

High Ionic Strength ◽

Acid Dissociation ◽

High Drug ◽

Overnight Incubation ◽

Antidrug Antibody ◽

High Doses

Aim: Antidrug antibody (ADA) assessment may be challenged in studies that involve the administration of high doses of biotherapeutics and/or with long half-lives. In such cases, ADA assays with optimized drug tolerance are desired. Material & Methods: We evaluated the use of MgCl2 to develop high ionic strength dissociation assays in two investigational examples (bridging enzyme-linked immunosorbent ADA assays) to attain high drug tolerance while maintaining best possible structural integrity of ADAs. Results: Both ADA-bridging assays treated with MgCl2 showed improved drug tolerance and higher signal-to-blank values compared with overnight incubation or acid treatment. Conclusion: The use of MgCl2 treatment in ADA-bridging assays provides a sensitive, drug tolerant and easy-to-use alternative in cases where acid dissociation is not possible or unwanted.

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High salt compatible oxyanion receptors by dual ion imprinting

Chemical Science ◽

10.1039/c9sc06508c ◽

2020 ◽

Vol 11 (16) ◽

pp. 4246-4250 ◽

Cited By ~ 1

Author(s):

Sudhirkumar Shinde ◽

Mona Mansour ◽

Anil Incel ◽

Liliia Mavliutova ◽

Celina Wierzbicka ◽

...

Keyword(s):

Ionic Strength ◽

Ion Pair ◽

High Ionic Strength ◽

High Salt ◽

Ion Uptake ◽

Ion Imprinting

Imprinting of an ion-pair in presence of mutually compatible anion and cation host monomers leads to polymers showing enhanced ion uptake in competitive high ionic strength buffers.

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