The stability of acid-soluble chromosomal proteins from avian erythrocytes

1968 ◽  
Vol 46 (8) ◽  
pp. 781-788 ◽  
Author(s):  
G. Vidali ◽  
J. M. Neelin
Keyword(s):  
Acetic Acid ◽  
Room Temperature ◽  
Starch Gel Electrophoresis ◽  
Guanidinium Chloride ◽  
Chromosomal Proteins ◽  
Avian Erythrocytes ◽  
Starch Gel ◽  
Avian Erythrocyte ◽  
The Stability ◽  
And Storage

The stability of avian erythrocyte histones was examined under the conditions of extraction, chromatography, electrophoresis, and storage, in order to avoid degradation during these operations. Since turbidity in trichloroacetic acid (TCA) was used as a measure of histone integrity, optimal conditions for quantitative assay were established as follows. One volume of histone sample was mixed with five volumes of 1.1 M TCA at room temperature, and the optical density at 400 mμ was measured after 25 min. The relation between turbidity and protein concentration was linear from 0.03 to at least 0.3 mg histone per milliliter and was not related to the kind of histone, except for the lysine-rich fraction which showed slightly less specific turbidity. Under these conditions turbidity was not sensitive to concomitant solutes such as guanidinium chloride, acetic acid, and dilute buffers and acids.With turbidity as the criterion of protein integrity, it was confirmed that brief manipulation in the cold is desirable in most media, including the dilute acids used for extraction. Nevertheless, chromatography at room temperature in concentrated solutions of guanidinium chloride or acetic acid appears to be tolerably safe. The effect of these conditions of manipulation and storage on histone fractions was substantiated by chromatography and starch-gel electrophoresis. Prolonged extraction of avian erythrocyte nuclei at acid pH released additional non-histone basic protein without alteration of authentic histone fractions.

Fractionation of Plasminogen by Starch Gel Electrophoresis

1964 ◽  
Vol 12 (01) ◽  
pp. 126-136 ◽  
Author(s):  
Karl H. Slotta ◽  
J. D Gonzalez
Keyword(s):  
Gel Electrophoresis ◽  
Room Temperature ◽  
Broad Band ◽  
Caproic Acid ◽  
Starch Gel Electrophoresis ◽  
Full Activity ◽  
Veronal Buffer ◽  
Starch Gel ◽  
Alkaline Range

SummaryWhen urea or ε-amino caproic acid were used as solublizing agents for plasminogen in electrophoretic experiments, only one broad band of the proenzyme was obtained on acetate cellulose, in starch block, and in acrylamide gel. In starch gel electrophoresis, however, both forms of plasminogen – the native or euglobulin and Kline’s or Pseudoglobulin plasminogen – separated into six bands. These migrated toward the cathode at room temperature in borate or veronal buffer in the alkaline range and showed full activity in fibrinagar-streptokinase plates.

scholarly journals Starch-Gel Electrophoresis of Wheat Flour Proteins

1963 ◽  
Vol 16 (2) ◽  
pp. 342 ◽  
Author(s):  
Janet SD Graham
Keyword(s):  
Acetic Acid ◽  
Wheat Flour ◽  
Gel Electrophoresis ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Starch Gel Electrophoresis ◽  
Similar Protein ◽  
Starch Gel ◽  
Protein Components ◽  
Electrophoresis Of Proteins

An improved apparatus and procedures for starch-gel electrophoresis of proteins of wheat flour are described; highly reproducible separation of the protein components was achieved. By starch-gel electrophoresis it was shown that similar protein components occur in the extracts of wheat flour obtained with a variety of solvents; however, there were marked differences in the proportions of these components in various extracts. Several protein components were present in the fJ'actions separated by ion-exchange chromatography of' the proteins soluble in Bodium pyrophosphate and of those soluble in acetic acid; some fractions containeda number of similar protein components.

scholarly journals The relationship between reversibility of fibril formation and subunit composition of rat skin collagen

1969 ◽  
Vol 113 (2) ◽  
pp. 419-422 ◽  
Author(s):  
D. W. Bannister
Keyword(s):  
Acetic Acid ◽  
Gel Electrophoresis ◽  
Fibril Formation ◽  
Subunit Composition ◽  
Starch Gel Electrophoresis ◽  
Rat Skin ◽  
Fractionation Procedure ◽  
Skin Collagen ◽  
Starch Gel ◽  
The Relationship

1. Salt-soluble rat skin collagen was precipitated from solution at neutral pH and 37°. On cooling, a portion of the collagen returned into solution. The fractions were separated, the supernatant was concentrated and the precipitate was redissolved in dilute acetic acid. 2. Solutions of supernatant and precipitate were subjected to the same fractionation procedure, giving four fractions. 3. Each fraction was examined by starch-gel electrophoresis and a relationship between subunit composition and the fractionation procedure was noted. The collagen that redissolved on cooling contained less of the more highly cross-linked components than did either the fraction remaining in the precipitate or the starting material.

Factors affecting measurement of urinary oxalate.

1984 ◽  
Vol 30 (8) ◽  
pp. 1339-1343 ◽  
Author(s):  
B C Mazzachi ◽  
J K Teubner ◽  
R L Ryall
Keyword(s):  
Ascorbic Acid ◽  
Room Temperature ◽  
Alkaline Ph ◽  
Ascorbic Acid Concentration ◽  
Factors Affecting ◽  
The Stability ◽  
Gas Chromatographic Method ◽  
And Storage ◽  
Urine Specimens ◽  
Positive Interference

Abstract Using a gas-chromatographic method, we examined the effects of phosphate concentration, added calcium chloride, and pH on precipitation of oxalate from urine. All three factors are important, but the pH of precipitation is particularly so, especially in the presence of even normal concentrations of ascorbic acid. At pH 8, increases in measured oxalate ranged from 20% at an ascorbic acid concentration of 1 mmol/L to more than 300% at 15 mmol/L. Ascorbic acid is rapidly converted to oxalate at alkaline pH. We also investigated the stability of both untreated and acidified urine containing ascorbic acid during storage for up to one month at -70, -20, and 4 degrees C, and room temperature. After one month, untreated collections were stable at -70 degrees C and acidified collections at -20 and -70 degrees C. We recommend conditions for assay and storage of urine specimens that are to be assayed for oxalate under which positive interference by ascorbic acid is minimized.

Hemoglobin Mahidol: a new hemoglobin α-chain mutant

1970 ◽  
Vol 48 (9) ◽  
pp. 1066-1078 ◽  
Author(s):  
S. Pootrakul ◽  
G. H. Dixon
Keyword(s):  
Acetic Acid ◽  
Gel Electrophoresis ◽  
Cyanogen Bromide ◽  
Starch Gel Electrophoresis ◽  
Abnormal Hemoglobin ◽  
Starch Gel ◽  
Α Chain ◽  
Acid Alteration ◽  
Peptide Maps ◽  
Amino Acid Alteration

A slow (less anionic) hemoglobin mutant has been detected by starch gel electrophoresis of hemoglobin from three unrelated patients in Bangkok. Dissociation of the abnormal hemoglobin with p-hydroxymercuribenzoate showed that the α-chain was the site of the mutation. The mutant α-chain was isolated by carboxymethylcellulose chromatography in 8 M urea and 0.05 M β-mercaptoethanol. Peptide maps of trypsin and cyanogen bromide cleaved α-chain indicated that the amino acid alteration of the mutant was in the peptide corresponding to residues 62–76 of the α-chain. Further cleavage of this peptide with 0.25 M acetic acid at 110 °C showed that residue 74 was changed from an aspartyl to a histidyl residue, a mutation not previously described. It is proposed that this new hemoglobin α274His β2A be called hemoglobin Mahidol after Mahidol University in Bangkok. In one of the three patients showing hemoglobin Mahidol, interaction with α-thalassemia occurs and, in this patient, hemoglobin A is totally absent, being replaced by hemoglobin Mahidol together with some hemoglobin H (β4A).

scholarly journals Banana liqueur made with yacon syrup: evaluation of stability during maturation

2021 ◽  
Vol 24 ◽  
Author(s):  
Leandro Levate Macedo ◽  
Wallaf Costa Vimercati ◽  
Cintia da Silva Araújo ◽  
Antonio Manoel Maradini Filho ◽  
Sérgio Henriques Saraiva ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Room Temperature ◽  
Color Difference ◽  
Maturation Time ◽  
Alcohol Content ◽  
Time Zero ◽  
The Stability ◽  
And Storage ◽  
Total Color Difference

Abstract The aim of this work was to evaluate the stability during maturation of banana liqueurs made with yacon syrup and sucrose. Thus, 20 °GL and 30 °Brix liqueurs were produced using yacon and sucrose syrups at concentrations of 42.8 and 45.0 °Brix. The liqueurs were subjected to two procedures as following: heat treatment at 70 °C for 20 min (tranchage), followed by storage at room temperature for 10 days (T42-T and T45-T); no heat treatment and storage at 50 °C for 10 days (T42-50 and T45-50). The color and turbidity of liqueurs were evaluated daily within 10 days of storage. The alcohol content was evaluated every 2 days. The total color difference (ΔE) was calculated in relation to color at time zero for each treatment. The T42-50 treatment had the lowest turbidity at the end of maturation. The T45-T treatment presented the lowest ΔE value at the end of maturation. The alcohol contents regarding the liqueurs were the same as those contents after elaboration as well as did not change over the maturation time for all treatments.

scholarly journals Stability of hepatitis B virus pregenomic RNA in plasma specimens under various temperatures and storage conditions

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e11207
Author(s):  
Pakkapon Rattanachaisit ◽  
Sirinporn Suksawatamnuay ◽  
Supachaya Sriphoosanaphan ◽  
Kessarin Thanapirom ◽  
Panarat Thaimai ◽  
...  
Keyword(s):  
Hepatitis B Virus ◽  
Hepatitis B ◽  
Room Temperature ◽  
Plasma Samples ◽  
Freeze Thaw ◽  
B Virus ◽  
The Mean ◽  
Clinically Significant ◽  
The Stability ◽  
And Storage

Background Hepatitis B virus (HBV) pregenomic RNA (pgRNA) has gained increasing attention owing to its role in replication of covalently closed circular DNA (cccDNA) in HBV. This marker has the potential to be used in clinical programs aimed to manage HBV infections. However, several reports on HBV pgRNA levels in clinical cases have conflicting results. RNA is easily degraded when exposed to heat and other environmental stressors. However, the stability of HBV pgRNA, during blood sample collection before the standard automated quantification, has never been estimated. This study aimed to demonstrate the effect of two different temperature conditions and storage durations on the stability of HBV pgRNA. Method Blood from forty patients with chronic hepatitis B infection, who also showed evidence of active HBV DNA replication, was collected and processed within 2 h of collection. Plasma from each patient was divided and stored at 4 °C and 25 °C (room temperature) for six different storage durations (0, 2, 6, 12, 24, and 48 h) and subsequently transferred to −80 °C for storage. The effect of multiple cycles of freezing and thawing of plasma at −20 °C or −80 °C was evaluated using samples from ten patients. Quantification of pgRNA from the samples was performed simultaneously, using the digital polymerase chain reaction (dPCR) method. The differences in pgRNA levels at baseline and each time point were compared using generalized estimating equation (GEE). A change greater than 0.5 log10 copies/mL of pgRNA is considered clinically significant. Statistical analyses were conducted using Stata 16.0. Results The mean HBV pgRNA level in the initially collected plasma samples was 5.58 log10copies/mL (ranging from 3.08 to 8.04 log10 copies/mL). The mean pgRNA levels in samples stored for different time periods compared with the initial reference sample (time 0) significantly decreased. The levels of pgRNA for 6, 12, 24, and 48 h of storage reduced by −0.05 log10 copies/mL (95% confidence interval (CI) −0.095 to −0.005, p = 0.03), −0.075 log10 copies/mL (95% CI [−0.12 to −0.03], p = 0.001), −0.084 log10 copies/mL (95% CI [−0.13 to −0.039], p =  < 0.001), and −0.120 log10 copies/mL (95% CI [−0.17 to −0.076], p =  < 0.001), respectively. However, these changes were below 0.5 log10 copies/mL and thus were not clinically significant. Compared with the samples stored at 4 °C, there were no significant differences in pgRNA levels in samples stored at 25 °C for any of the storage durations (−0.01 log10 copies/mL; 95% CI [−0.708 to 0.689], p = 0.98). No significant difference in the levels of pgRNA was observed in the plasma samples, following four freeze-thaw cycles at −20 °C and −80 °C. Conclusion The plasma HBV pgRNA level was stable at 4 °C and at room temperature for at least 48 h and under multiple freeze-thaw cycles. Our results suggest that pgRNA is stable during the process of blood collection, and therefore results of pgRNA quantification are reliable.

scholarly journals Evaluation of an ELISA for metanephrines in feline urine

2018 ◽  
Vol 30 (6) ◽  
pp. 887-893
Author(s):  
Thanikul Srithunyarat ◽  
Anna Svensson ◽  
Sofia Hanås ◽  
Odd V. Höglund ◽  
Ragnvi Hagman ◽  
...  
Keyword(s):  
Neuroendocrine Tumors ◽  
Home Environment ◽  
Human Urine ◽  
Room Temperature ◽  
Storage Time ◽  
Stability Study ◽  
Urine Samples ◽  
Urine Sampling ◽  
The Stability ◽  
And Storage

Catecholamines can be used to evaluate neuroendocrine tumors, stress, and potentially pain, but catecholamines degrade rapidly. Their metabolites normetanephrine (NME) and metanephrine (ME) have better stability in urine. In cats, urine sampling in a home environment would be beneficial to reduce effects of clinical stress and simplify sampling. We evaluated a human urine ELISA for analysis of NME and ME in feline urine, and investigated the effects of acidification, cat tray pellets, and storage time at room temperature up to 8.5 h. In 26 feline urine samples, mean NME concentration was 192 ± 80 ng/mL, mean intra- and inter-assay CV was 6.5% and 4.2%, respectively, and spike recovery was 98–101%, but dilutional recovery was unsatisfactory. For ME, mean intra- and inter-assay CV was 10.2% and 4.1%, respectively. Mean urine ME concentration was 32.1 ± 18.3 ng/mL, close to the kit’s lowest standard, and spike recovery was 65–90%; the ELISA could not be validated for ME. The stability study, performed for NME on 12 urine samples, did not identify differences between acidified and non-acidified samples, cat tray pellets, or storage time, and no interaction effects. The ME ELISA was not suitable for feline urine; performance of the NME ELISA was acceptable, except for dilution recovery. For analysis of NME, feline urine can be sampled at home using cat tray pellets and stored at room temperature up to 8.5 h without acidification.

Simplified Preparation of Blood Hemolysates for Hemoglobin Electrophoresis

1965 ◽  
Vol 11 (6) ◽  
pp. 628-632 ◽  
Author(s):  
R Quentin Blackwell ◽  
Jeanette Tung-Hsiang Huang
Keyword(s):  
Gel Electrophoresis ◽  
Red Cells ◽  
Starch Gel Electrophoresis ◽  
Sample Collection ◽  
Blood Samples ◽  
Blood Clots ◽  
Starch Gel ◽  
Simplified Procedure ◽  
And Storage

Abstract Hemolysates made directly from unwashed red cells or unwashed blood clots can be used successfully for screening populations for abnormal hemoglobins by starch-gel electrophoresis. The cells or clot, mixed with an equal volume of water, are frozen overnight or longer, and the resulting supernatant hemolysate used directly for electrophoresis. The simplified procedure has been used to identify several abnormal hemoglobins including A+E, A+H, A+J, and electrophoretically fast fetal hemoglobins. The principal advantages of the procedure include substantial economy in time and increased flexibility in sample collection and storage. The method is particularly useful with small blood samples collected without venipuncture.

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