scholarly journals Validation of a commercial enzyme immunoassay to assess urinary oxytocin in humans

2021 ◽  
Vol 10 (3) ◽  
pp. 290-301
Author(s):  
Franka S Schaebs ◽  
Gwen Wirobski ◽  
Sarah Marshall-Pescini ◽  
Friederike Range ◽  
Tobias Deschner

Within the last decade, oxytocin (OT) has attracted a lot of attention in the context of various human social behaviors. Besides its importance in regulating physiological processes in females related to giving birth and lactation, OT is involved in the establishment and maintenance of social relationships, trust and emotion recognition. However, results are not always consistent across studies, which may partly be due to the incomplete validation of methods used to assess OT levels. Carefully validating a method before its use is of crucial importance to ensure that it can be used to accurately, reliably and repeatedly assess OT levels. With this study we evaluated a commercially available Enzyme Immunoassay to assess OT in human urine samples by conducting a careful analytical validation. Results indicate that, with regard to parallelism and immunoreactivity, human urinary OT can be assessed reliably. However, extraction methods need further improvement to optimize measures of accuracy and extraction efficiency, especially in the lower range of the assay system. Tests on OT stability indicate that OT is affected by degradation when stored at 4°C or room temperature. Storing urine samples over longer periods revealed that OT levels are most stable when stored as ethanol extracts at −20°C compared to being stored as samples at −20°C or −80°C. Although some of the validated parameters did not reach the intended quality criteria, this study highlights the importance of such in depth validation procedures and reporting results to make them available to researchers embarking on projects utilizing such methods.

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
G. Wirobski ◽  
F. S. Schaebs ◽  
F. Range ◽  
S. Marshall-Pescini ◽  
T. Deschner

AbstractOxytocin (OT) promotes pro-sociality, bonding, and cooperation in a variety of species. Measuring oxytocin metabolite (OTM) concentrations in urine or saliva provides intriguing opportunities to study human and animal behaviour with minimal disturbance. However, a thorough validation of analytical methods and an assessment of the physiological significance of these measures are essential. We conducted an analytical validation of a commercial Enzyme Immunoassay (EIA; Arbor OT assay kit) to measure OTM concentrations in dog, wolf, and human urine samples. To test the assay’s ability to detect changes in OTM concentrations, we administered oxytocin intranasally to 14 dogs. Assay performance with regard to parallelism was acceptable. Assay accuracy and extraction efficiency for dog and wolf samples were comparable to a previously validated assay (Enzo OT assay kit) but variation was smaller for human samples. Binding sensitivity and antibody specificity were better in the Arbor assay. Average OTM concentrations were more than twice as high as in comparable samples measured with the Enzo assay, highlighting a lack of comparability of absolute values between different assays. Changes in OTM concentrations after intranasal treatment were detected reliably. The Arbor assay met requirements of a “fit-for-purpose” validation with improvement of several parameters compared to the Enzo assay.


1998 ◽  
Vol 36 (9) ◽  
pp. 2718-2722 ◽  
Author(s):  
J. A. Domínguez ◽  
N. Galí ◽  
P. Pedroso ◽  
A. Fargas ◽  
E. Padilla ◽  
...  

We evaluated a newly commercial enzyme immunoassay (EIA) (BiotestLegionella Urin Antigen EIA; Biotest AG, Dreieich, Germany) for detection of antigens of all Legionella pneumophilaserogroups with a relatively wide spectrum of cross-reactivity as well as antigens of other Legionella spp. by comparing its sensitivity and specificity with those of an EIA for detection ofL. pneumophila serogroup 1 antigen (Legionella urinary antigen EIA; Binax, Portland, Maine). Both tests were performed with both concentrated and nonconcentrated urine samples. We also evaluated the capabilities of both EIAs to detect extracted soluble antigens of American Type Culture Collection (ATCC) Legionella strains (L. pneumophila serogroups 1 to 14, L. bozemanii, and L. longbeachae). The sensitivity of the Biotest EIA was 66.66% in nonconcentrated urine and 86.66% in concentrated urine. The sensitivity of the Binax EIA was 63.76% and 88.88% in nonconcentrated and concentrated urine, respectively. The specificity was 100% in nonconcentrated and concentrated urine for both assays. The Binax EIA and Biotest EIA detected extracted soluble antigens of L. pneumophila serogroups 1 to 14 and L. bozemanii ATCC strains. The cross-reactions observed with the Binax EIA were probably due to common epitopes directly related to lipopolysaccharide. Further studies are required to determine the usefulness of the Binax EIA for detection of urinary antigens fromLegionella species and serogroups other than L. pneumophila serogroup 1. The Biotest EIA proved to be as rapid, sensitive, and specific as the Binax EIA for the diagnosis of legionellosis. Concentration of antigen present in urine increased the sensitivities of both techniques with no reduction in specificity.


1989 ◽  
Vol 121 (4) ◽  
pp. 513-519 ◽  
Author(s):  
Hiroshi Tomita ◽  
Masamichi Ogawa ◽  
Takashi Kamijo ◽  
Osamu Mori ◽  
Eiji Ishikawa ◽  
...  

Abstract. GH values were determined by a highly sensitive sandwich enzyme immunoassay in the 1st morning and/or 24-h accumulated urine samples in 94 children (short stature 70, including 14 with complete GH deficiency, 9 with partial GH deficiency, and 47 with GH-normal short stature; Turner's syndrome, 10, and simple obesity, 14). GH values were also determined in the 2nd to 4th urine samples taken on the same day together with the 1st morning urine in 5 of them. GH values in the 1st morning urine correlated significantly with those of the 24-h urine and with serum peak and mean GH values during nocturnal sleep as a physiological GH secretion test. The 2nd to 4th urines had lower GH concentrations than the 1st morning urine. The GH value of the 1st morning urine in complete GH deficiency was significantly lower than those in GH-normal short stature, partial GH deficiency and Turner's syndrome. However, no significant difference was detected in urinary GH values between complete GH deficiency and simple obesity. We conclude that 1st morning urinary GH estimation may be useful for differentiation of complete GH deficiency from other causes of short stature, but may be difficult for the distinction between complete GH deficiency and obesity with normal GH secretory ability.


2020 ◽  
Vol 16 (7) ◽  
pp. 893-904
Author(s):  
Alessandra von Ahn ◽  
João Henrique Z. dos Santos

Background: The official compendium of the quantification of ginkgo flavonoids from Ginkgo biloba extract has been proposed using HPLC. The drawbacks of this technique appear to be due to the restricted efficiency in terms of the recovery results and suitability of the system for the quantification of these compounds. This study investigated the potential advantages and limitations of the development of efficient extraction methods for the recovery of flavonol glycosides (quercetin, kaempferol and isorhamnetin) and terpene trilactones (bilobalide, ginkgolide A, ginkgolide B and ginkgolide C) using extraction, quantification and detection techniques, namely, GC-FID and UHPLC-DAD, which are alternatives to those techniques available in the literature. Methods: Two different extraction methodologies have been developed for the determination of flavonoids (quercetin, kaempferol and isorhamnetin) and terpene trilactones (bilobalide, ginkgolide A, ginkgolide B and ginkgolide C) using ultra-high-pressure liquid chromatography coupled to a diode array detector and gas chromatography coupled to a flame ionization detector. Results: In this study, the Ginkgo biloba extract mass, hydrolysis preparation method (with or without reflux), and volume of the extraction solution seemed to affect the ginkgo flavonoid recovery. The UHPLC-based method exhibited higher extraction efficiency for ginkgo flavonoid quantification compared to the pharmacopoeial method. The developed method exhibited higher extraction efficiency for terpene quantification compared to the previous method that used extractive solution without pH adjustment, with less time of extraction and less amount of the sample and organic solvent aliquots. Conclusion: The UHPLC and GC analysis methods established in this study are both effective and efficient. These methods may improve the quality control procedures for ginkgo extract and commercial products available in today´s natural health product market. The results indicate that redeveloped extraction methods can be a viable alternative to traditional extraction methods.


2017 ◽  
Vol 6 (04) ◽  
pp. 5343
Author(s):  
Ragni Vora ◽  
Ambika N. Joshi* ◽  
Nitesh C. Joshi

Mucuna pruriens seeds are noted to be a natural source of L-DOPA and are also used as a substitute for the synthetic L-DOPA. In the present study; attempts are made to develop suitable method(s) for extraction of L-DOPA from the powdered seeds of Mucuna pruriens using different solvents and conditions. The Seed powder was subjected to 7 different extraction methods and Method 1 was subjected to various solvent concentrations. Some methods used de-fatting procedure, either the method was cold maceration or in high temperature. Soxhlet extraction was also used in one of the extraction methods. All the extracts were analyzed using RP-HPLC. Mobile Phase used was Water: Methanol: AcetoNitrile (100:60:40) (v/v) containing 0.2% Triethylamine, pH = 3.3 and monitored at 280 nm with variable wavelength UV detector. The extraction was best with Methanol Water mixture in a cold maceration technique and overall gives good extraction efficiency of 13.36 % L-DOPA and id the best method giving highest extraction efficiency. The De-fatting method was the 2nd best methods giving approximately 8.8% L-DOPA and Method 5 viz, heat reflux method gives 8.7% L-DOPA making it the 3rd best method. There are not many studies done for optimization of extraction technique for L-DOPA despite an extensive work is reported for isolation, identification and pharmacological activities of L-DOPA from various plant sources. Keeping this in view, present investigation was done to study the extraction efficiency of various extraction methods of L-DOPA content in seed extracts of Mucuna pruriens and compare it.


2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Maura Turriani ◽  
Nicola Bernabò ◽  
Barbara Barboni ◽  
Gianluca Todisco ◽  
Luigi Montini ◽  
...  

Serinus canariais a widespread domestic ornamental songbird, whose limited knowledge of biology make compelling studies aimed to monitor stress. Here, a commercial enzyme immunoassay was adopted to measure immunoreactive corticosterone (CORT) in singleSerinus canariadropping sample, to monitor the daily fecal excretion of CORT in birds bred singly or in-group and to detect the effect promoted by aviary or small transport cage restraint. A robust daily rhythm of CORT was recorded in animals held on short-day light cycle, independent of bred conditions (single or group), which persisted when space availability was modified in single bred animal (transfer in aviary and transport cages). By contrast, a significant change in CORT excretion was recorded when group bred animals are restrained in a smaller cage. The daily rhythm in CORT excretion in response to manipulation showed the greatest response at the beginning of the light period, followed by the absence of the peak usually recorded at the end of the dark phase. These data indicated that EIA could be used as a reliable noninvasive approach to monitor the stress induced by restraint conditions inSerinus canaria.


Water ◽  
2021 ◽  
Vol 14 (1) ◽  
pp. 46
Author(s):  
Yonghua Wang ◽  
Na Li ◽  
Shengnan Jiang ◽  
Xi Chen

Water sources are an indispensable resource for human survival. Monitoring the pollution status of the surrounding environment is necessary to protect water sources. Research on the environmental matrix of deep eutectic solvents (DESs) has expanded rapidly because of their high extraction efficiency for various target analytes, controllable synthesis, and versatile structure. Following the synthesis of hydrophobic deep eutectic solvents (HDESs), their application in aqueous matrices broadened greatly. The present review conducted a survey on the pollutant extraction methods based DESs in environmental matrices from two aspects, application methods and matrix types; discussed the potential risk of DESs to the environment and future development trends; and provided some references for researchers to choose DES-based extraction methods for environmental research.


2019 ◽  
Author(s):  
Teresa L. Street ◽  
Leanne Barker ◽  
Nicholas D. Sanderson ◽  
James Kavanagh ◽  
Sarah Hoosdally ◽  
...  

AbstractBackgroundEmpirical gonorrhoea treatment at initial diagnosis reduces onward transmission. However, increasing resistance to multiple antibiotics may necessitate waiting for culture-based diagnostics to select an effective treatment. There is a need for same-day culture-free diagnostics that identify infection and detect antimicrobial resistance.MethodsWe investigated if Nanopore sequencing can detect sufficient N. gonorrhoeae DNA to reconstruct whole genomes directly from urine samples. We used N. gonorrhoeae spiked urine samples and samples from gonorrhoea infections to determine optimal DNA extraction methods that maximize the amount of N. gonorrhoeae DNA sequenced whilst minimizing contaminating host DNA.ResultsIn simulated infections the Qiagen UCP Pathogen Mini kit provided the highest ratio N. gonorrhoeae to human DNA and the most consistent results. Depletion of human DNA with saponin increased N. gonorrhoeae yields in simulated infections, but decreased yields in clinical samples. In ten urine samples from men with symptomatic urethral gonorrhoea, ≥87% coverage of an N. gonorrhoeae reference genome was achieved in all samples, with ≥92% coverage breath at ≥10-fold depth in 7 (70%) samples. In simulated infections if ≥104 CFU/ml of N. gonorrhoeae was present, sequencing of the large majority of the genome was frequently achieved. N. gonorrhoeae could also be detected from urine in cobas PCR Media tubes and from urethral swabs, and in the presence of simulated Chlamydia co-infection.ConclusionUsing Nanopore sequencing of urine samples from men with urethral gonorrhoea sufficient data can be obtained to reconstruct whole genomes in the majority of samples without the need for culture.


2020 ◽  
Vol 1 (40) ◽  
pp. 39-49
Author(s):  
Hau Thu Nguyen Thi ◽  
Dung Nhan Tran ◽  
Ba Van Huynh ◽  
Quyen Ngoc Thi ◽  
An Tran Hoang Bui ◽  
...  

Pineapple (Ananas comosus) is a kind of fruit with high nutritional value. This study investigated the resistance to oxidation DPPH (2,2-Diphenyl-1picrylhydrazyl (free radical) and deionized Fe3+ of ethanol extracts from theleaves (leaves grow on stems) and crown (crown of scale leaves) of pineapples. Study of high extraction efficiency in 99,5% ethanol solvent, mixing ratio between samples with the solvent is 1 : 4, combined ultrasonic wave with a capacity of 120 Walt within 72 hours. The total polyphenol content in all treatments was high: leave sample (140,9 ± 2,86 mg GAE/g) and crown sample (204,6 ± 0,29 mg GAE/g). The results showed thatDPPH oxidation resistance and deionized Fe3+ were: crown (IC50 = 254,74 ± 1,55 mg/mL và 908,12 ± 9,35 mg/mL) higher than leaves (IC50 = 977,78 ± 30,27m mg/mL and 2156,62 ± 23,03 mg/mL). Theresearch has found that the use of waste products from pineapple peels with antioxidant capacity could be added to potential raw materials in the field of pharmaceutical production.


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