scholarly journals Macroprolactinaemia: Contribution to Hyperprolactinaemia in a District General Hospital and Evaluation of a Screening Test Based on Precipitation with Polyethylene Glycol

1997 ◽  
Vol 34 (3) ◽  
pp. 252-258 ◽  
Author(s):  
M N Fahie-Wilson ◽  
S G Soule
Keyword(s):  
Polyethylene Glycol ◽  
Screening Test ◽  
Reference Range ◽  
Gel Filtration ◽  
District General Hospital ◽  
Serum Prolactin ◽  
Common Phenomenon ◽  
Common Cause ◽  
Upper Limit ◽  
Polyethylene Glycol 6000

For a period of 12 months all samples submitted for serum prolactin (PRL) assay and with PRL>700mU/L were examined by gel filtration chromatography. In 17 (25%) of 69 samples we found macroprolactin. The Delfia and Immuno 1 immunoassay systems gave similar PRL results with samples containing macroprolactin whereas the ACS 180 system gave lower results. With the Delfia and Immuno 1 systems samples containing substantial quantities of macroprolactin showed low recovery of PRL after precipitation with polyethylene glycol 6000 (PEG 6000) and this technique can be used as a screening test for macroprolactinaemia. We conclude that macroprolactinaemia is a common phenomenon and, in assays which detect this species, is a common cause of hyperprolactinaemia. Macroprolactinaemia may contribute to the difficulty in establishing an upper limit of the reference range for serum PRL. In our experience, patients with macroprolactinaemia do not exhibit features of the hyperprolactinaemia syndrome and it is important to recognize macroprolactin as the cause of hyperprolactinaemia to avoid unnecessary investigation and treatment.

A new automated turbidimetric immunoassay for quantifying alpha 1-antitrypsin in serum.

1986 ◽  
Vol 32 (6) ◽  
pp. 1020-1022 ◽  
Author(s):  
J A Viedma ◽  
A de la Iglesia ◽  
M Parera ◽  
M T López
Keyword(s):  
Polyethylene Glycol ◽  
Parametric Estimation ◽  
Tween 20 ◽  
Upper Limit ◽  
Analytical Recovery ◽  
The Mean ◽  
Alpha 1 Antitrypsin ◽  
Polyethylene Glycol 6000 ◽  
Immunoprecipitation Reaction ◽  
Turbidimetric Immunoassay

Abstract This rapid, sensitive equilibrium turbidimetric immunoassay for quantification of alpha 1-antitrypsin involves a monospecific antibody, polyethylene glycol 6000 to accelerate and enhance the immunoprecipitation reaction, and Tween 20 surfactant to decrease and stabilize the sample-blank values. Turbidity at 334 nm is measured by an automated discrete analyzer. Grossly lipemic, icteric, or hemolyzed samples can be assayed. Correlation with results by radial immunodiffusion (RID) was excellent (r = 0.97, n = 84). Analytical recovery averaged 97.7 (SD 2.9)%. Within-run CVs ranged from 1.6 to 1.9%, between-day CVs from 2.0 to 3.5%. Reference values for healthy adults (n = 147) were determined by parametric estimation (for an assumed normal distribution of untransformed data). The lower limit (g/L) with its 0.90 confidence interval is 1.23 (range 1.18-1.28), the upper limit is 2.15 (2.10-2.20), and the mean is 1.69 g/L.

Heparin Cofactor II: Purification and Antibody Production

1986 ◽  
Vol 55 (01) ◽  
pp. 019-023 ◽  
Author(s):  
Tri H Tran ◽  
B Lämmle ◽  
B Zbinden ◽  
F Duckert
Keyword(s):  
Polyethylene Glycol ◽  
Antithrombin Iii ◽  
Gel Filtration ◽  
Good Separation ◽  
Heparin Cofactor Ii ◽  
Specific Test ◽  
Sepharose 4B ◽  
Heparin Affinity ◽  
Polyethylene Glycol 6000 ◽  
Free Plasma

Heparin cofactor II (HCII) was purified from plasma to homogeneity. The procedure includes adsorption with (Al)OH3, fractionation with polyethylene glycol 6000, chromatography on QAE-Sephadex A-50, on heparin-Sepharose 4B and on Sephadex G-150. QAE-Sephadex A-50 chromatography provides a good separation of HCII from antithrombin III (AT) and most contaminants having a heparin affinity similar to that of HCII. HCII is eluted at 0.28 M NaCl from the heparin-Sepharose column. After gel filtration on G-150, contaminating AT was removed by immunoadsorption. Purified HCII shows an apparent Mr of 66,500 dal tons as analyzed on SDS-polyacrylamide gel and 62,100 daltons by ultracentrifugation. Antibodies to HCII were raised in rabbits. Former antisera mostly directed to a contaminating protein were used to remove it from the HCII preparation. Antibodies to HCII were made monospecific by immunoadsorption on HCII-free plasma linked to Sepharose 4B. Since many functional AT assays have neglected the presence of HCII in plasma, antibodies to HCII using as immunoadsorbent will provide a more specific test for AT.

scholarly journals Serum prolactin revisited: parametric reference intervals and cross platform evaluation of polyethylene glycol precipitation-based methods for discrimination between hyperprolactinemia and macroprolactinemia

2017 ◽  
Vol 55 (11) ◽  
Author(s):  
Martin Overgaard ◽  
Susanne Møller Pedersen
Keyword(s):  
Polyethylene Glycol ◽  
Elevated Serum ◽  
Gel Filtration ◽  
Reference Interval ◽  
Reference Intervals ◽  
Serum Prolactin ◽  
Specific Reference ◽  
Screening Methods ◽  
Discriminative Ability ◽  
Discrimination Methods

AbstractBackground:Hyperprolactinemia diagnosis and treatment is often compromised by the presence of biologically inactive and clinically irrelevant higher-molecular-weight complexes of prolactin, macroprolactin. The objective of this study was to evaluate the performance of two macroprolactin screening regimes across commonly used automated immunoassay platforms.Methods:Parametric total and monomeric gender-specific reference intervals were determined for six immunoassay methods using female (n=96) and male sera (n=127) from healthy donors. The reference intervals were validated using 27 hyperprolactinemic and macroprolactinemic sera, whose presence of monomeric and macroforms of prolactin were determined using gel filtration chromatography (GFC).Results:Normative data for six prolactin assays included the range of values (2.5th–97.5th percentiles). Validation sera (hyperprolactinemic and macroprolactinemic; n=27) showed higher discordant classification [mean=2.8; 95% confidence interval (CI) 1.2–4.4] for the monomer reference interval method compared to the post-polyethylene glycol (PEG) recovery cutoff method (mean=1.8; 95% CI 0.8–2.8). The two monomer/macroprolactin discrimination methods did not differ significantly (p=0.089). Among macroprolactinemic sera evaluated by both discrimination methods, the Cobas and Architect/Kryptor prolactin assays showed the lowest and the highest number of misclassifications, respectively.Conclusions:Current automated immunoassays for prolactin testing require macroprolactin screening methods based on PEG precipitation in order to discriminate truly from falsely elevated serum prolactin. While the recovery cutoff and monomeric reference interval macroprolactin screening methods demonstrate similar discriminative ability, the latter method also provides the clinician with an easy interpretable monomeric prolactin concentration along with a monomeric reference interval.

scholarly journals Specificity and Clinical Utility of Methods for the Detection of Macroprolactin

2006 ◽  
Vol 52 (7) ◽  
pp. 1366-1372 ◽  
Author(s):  
Lucille Kavanagh ◽  
T Joseph McKenna ◽  
Michael N Fahie-Wilson ◽  
James Gibney ◽  
Thomas P Smith
Keyword(s):  
Polyethylene Glycol ◽  
Clinical Utility ◽  
Protein A ◽  
Gel Filtration ◽  
Protein G ◽  
Serum Concentrations ◽  
Gel Filtration Chromatography ◽  
Common Cause ◽  
Choice Alternative ◽  
First Choice

Abstract Background: Increased serum concentrations of macroprolactin are a relatively common cause of misdiagnosis and mismanagement of hyperprolactinemic patients. Methods: We studied sera from a cohort of 42 patients whose biochemical hyperprolactinemia was explained entirely by macroprolactin. Using 5 pretreatments, polyethylene glycol (PEG), protein A (PA), protein G (PG), anti-human IgG (anti-hIgG), and ultrafiltration (UF), to deplete macroprolactin from sera before immunoassay, we compared residual prolactin concentrations with monomer concentrations obtained by gel-filtration chromatography (GFC). A monomeric prolactin standard was used to assess recovery and specificity of the pretreatment procedures. Results: Residual prolactin concentrations in all pretreated sera differed significantly (P <0.001) from monomeric concentrations obtained after GFC. PEG underestimated (mean, 75%), whereas PA, PG, anti-hIgG, and UF overestimated (means, 178%, 151%, 178%, and 112%, respectively) the amount of monomer present. Of the 5 methods examined, PEG correlated best with GFC (r = 0.80) followed by PG (r = 0.78), PA (r = 0.72), anti-hIgG (r = 0.70), and UF (r = 0.61). After UF or pretreatment with anti-hIgG or PEG, recovery of monomeric prolactin standard was low: 60%, 85%, and 77% respectively. In contrast, pretreatment with PA or PG gave almost quantitative recovery. Conclusions: None of the methods examined yielded results identical to the GFC method. PEG pretreatment yielded results that correlated best and is recommended as the first-choice alternative to GFC.

Hepatitis a Virus Concentration from Experimentally Contaminated Distilled, Tap, Waste and Seawater

1989 ◽  
Vol 21 (3) ◽  
pp. 255-258 ◽  
Author(s):  
Evangélos Biziagos ◽  
Jacques Passagot ◽  
Jean-Marc Crance ◽  
Robert Deloince
Keyword(s):  
Cell Culture ◽  
Polyethylene Glycol ◽  
Hepatitis A ◽  
Hepatitis A Virus ◽  
Tap Water ◽  
Virus Concentration ◽  
Beef Extract ◽  
Polyethylene Glycol 6000

The concentration of cell-culture-adapted hepatitis A virus (HAV) from experimentally contaminated distilled, drinking, waste and seawater was performed by using a filter adsorption-elu-tion method in the following conditions: HAV seeded in water was adsorbed at pH 4.0 to two nitrocellulose membranes (1.2 and 0.45 µm porosity for distilled and tap water or 8.0 and 3.0 µm porosity for waste and seawater), then eluted by 3% beef-extract at pH 8.5 and further concentrated by polyethylene glycol 6000 precipitation. Thus, HAV in 5 to 50 liters of seeded waters was concentrated approximately 1,700 to 17,000 fold with greater than 70% recovery of the initial virus added to the samples.

scholarly journals TSH reference range in older adults: a Brazilian study

2014 ◽  
Vol 58 (4) ◽  
pp. 389-393 ◽  
Author(s):  
Pedro Weslley Rosario ◽  
Maria Regina Calsolari
Keyword(s):  
Older Adults ◽  
Thyroid Dysfunction ◽  
Elderly Population ◽  
Thyroid Nodules ◽  
Reference Range ◽  
Adult Population ◽  
Free T4 ◽  
Upper Limit ◽  
Thyroperoxidase Antibodies ◽  
Serum Tsh

Objective: To establish serum TSH reference values for a population of Brazilian elderly, and to compare them to those found in the adult population. Subjects and methods: Healthy volunteers aged 70 to 85 years, without known thyroid disease or risk factors for thyroid dysfunction, who did not use any medication that could potentially interfere with TSH, were selected. Subjects with goiter, palpable thyroid nodules, anti-thyroperoxidase antibodies, or altered free T4 were excluded. The sample consisted of 360 older adults (180 per sex). Results: TSH values corresponding to the 2.5th and 97.5th percentile of the sample were 0.2 and 4.62 mIU/L, respectively. TSH > 2.5 mIU/L was seen in 25.26% of the volunteers, > 3 mIU/L in 15.26%, and > 4 mIU/L in 6.1% of them. TSH values were slightly higher than those previously reported for adults (18-60 years). Conclusion: This study suggests an upper limit for normal TSH of approximately 4.6 mIU/L for the Brazilian elderly population.

scholarly journals False low holotranscobalamin levels in a patient with a novel TCN2 mutation

2016 ◽  
Vol 54 (11) ◽  
Author(s):  
Peter Keller ◽  
Janine Rufener ◽  
Christof Schild ◽  
Sergey N. Fedosov ◽  
Peter H. Nissen ◽  
...  
Keyword(s):  
Point Mutation ◽  
Serum Sample ◽  
Screening Test ◽  
Initial Treatment ◽  
Sanger Sequencing ◽  
Single Point ◽  
Gel Filtration ◽  
Reference Interval ◽  
Single Point Mutation ◽  
Abbott Architect

AbstractBackground:Measurement of holotranscobalamin (holoTC) is increasingly used as a screening test for cobalamin (Cbl) deficiency. A level well below the reference interval strongly supports a deficient state. We examined a 21-year-old woman diagnosed as Cbl deficient because of an extremely low holoTC level as measured by the Abbott Architect Assay.Methods:The patient was evaluated for Cbl deficiency employing an in-house holoTC method as well as other routine markers of Cbl status. Further analyses included exploration of the Cbl binding proteins employing gel filtration of a serum sample saturated with 57 Co-labeled Cbl and Sanger sequencing of exons 1–9 and the intron-exon boundaries of theResults:The patient had normal hematological variables throughout. Despite initial treatment with Cbl, holoTC as measured by the Abbott assay remained low, while holoTC measured with the in-house assay was normal, and behaved as TC upon gel-filtration. By Sanger sequencing, we detected a homozygous single point mutation c.855T>A in exon 6 ofConclusions:We describe a novel point mutation of the

scholarly journals Assessment of the Effects of SARS-Cov-2 Infection on Multiple Organs Using Laboratory Indices

2021 ◽  
Vol 17 (2) ◽  
pp. 73-78
Author(s):  
Jianwei Zhou ◽  
Yu Li ◽  
Cui Kong ◽  
Yizhao Li ◽  
Yao Liang
Keyword(s):  
Reference Range ◽  
Normal Range ◽  
Causative Mechanism ◽  
Gamma Glutamyltransferase ◽  
Multiple Organs ◽  
Upper Limit ◽  
Laboratory Results ◽  
Heart Injury ◽  
Beta 2 Microglobulin ◽  
Biochemical Indices

Background: Severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2) is still a severe threaft for human health currently, and the researches about it is a focus topic worldwide. Aim of the study: In this study, we will collect some laboratory results of the patients with coronavirus disease (COVID-19) to assess the function of liver, heart, kidney and even pancreas.  Subjects and Methods: Laboratory results of the patients with COVID-19 are collected. The biochemical indices are classified and used to assess the according function of liver, heart, kidney; meantime, and blood glucose is also observed and taken as an index to roughly evaluate pancreas. Results: There were some indices exhibited abnormal. For patient 1, the ratio of albumin and globulin slightly was lower than the down-limit of reference range. For patient 2, alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyltransferase (GGT), creatine kinase (CK), creatinine kinase-MB isoenzyme (CK-MB), lactate dehydrogenase (LDH), alpha-hydroxybutyric dehydrogenase (HBDH), and beta-2 microglobulin (β2-MG) were respectively higher than the according upper limit of the reference range, while prealbumin (PA) was lower than the down limit. For patient 3, GGT, CK, PA were high than normal range. For patient 4, CK, LDH, HBDH were higher than the upper range. Conclusion: Infection of SARS-Cov-2 could cause liver and heart injury, and it is suggested that clinicians and researchers should pay more attention on the prevention, treatment and causative mechanism of such an injury.

scholarly journals High Molecular Weight Factor VIII Coagulant Activity in Cryoprecipitate and Polyethylene Glycol Precipitates

1977 ◽  
Author(s):  
K. A. Rickard ◽  
T. Exner ◽  
H. Kronenberg
Keyword(s):  
Molecular Weight ◽  
Polyethylene Glycol ◽  
Factor Viii ◽  
High Molecular Weight ◽  
Gel Filtration ◽  
Lower Molecular Weight ◽  
Human Antibody ◽  
High Molecular Weight Material ◽  
Coagulant Activity ◽  
Molecular Weight Form

Gel filtration of human plasma cryoprecipitate on Sepharose 2B indicated the molecular weight of factor VIII coagulant activity (VIIIc) to be significantly greater than that found in antihaemophilic concentrate. Polyethylene glycol at 3% concentration precipitated approximately half of the VIIIc from cryoprecipitate. This activity eluted as high molecular weight material on gel filtration. The addition of more polyethylene glycol to a concentration of 8% precipitated most of the remaining VIIIc from cryoprecipitate. This activity appeared to be of significantly lower molecular weight, approximately corresponding in elution volume to that observed for antihaemophilic concentrate. The possibility that an antibody to VIIIc generated in a patient treated with cryoprecipitate might be directed against the higher molecular weight form of factor VIII was investigated. However, no significant differences between the higher and lower molecular weight forms of factor VIII either in stability or in reactivity with human antibody to factor VIII were found.

Screening for macroamylase in a community hospital.

1984 ◽  
Vol 30 (5) ◽  
pp. 741-742 ◽  
Author(s):  
C A Isham ◽  
N A Ridgeway ◽  
R Hedrick ◽  
J C Cate
Keyword(s):  
Polyethylene Glycol ◽  
Community Hospital ◽  
Serum Amylase ◽  
Gel Filtration ◽  
Screening Procedure ◽  
Gel Filtration Chromatography ◽  
Polyethylene Glycol Precipitation ◽  
Precipitation Test

Abstract We evaluated the polyethylene glycol precipitation test (Gastroenterology 83: 378-382, 1982), looking for macroamylase in the serum of 66 patients whose values for serum amylase were above normal. Three patients (4.5%) were identified by this method as having macroamylase , and this was confirmed by gel-filtration chromatography and electrophoresis. We find this to be the test of choice as a screening procedure for macroamylasemia because of its speed, simplicity, and apparent reliability. Diagnosis of macroamylasemia is important in preventing needless treatment and investigation for pancreatitis.

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