Steroid analysis for medical diagnosis

Nozaki, Osamu

doi:10.1016/s0021-9673(01)01104-9

Cited by 88 publications

(61 citation statements)

References 56 publications

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“…Analyses of testosterone levels in body fluids are of great importance in medical diagnosis of hirsutism, polycystic ovary disease, hypogonadism, and virilization [1]. Owing to the myotrophic action, testosterone is also misused as a doping agent, although prohibited by the Medical Commission of the International Olympic Committee (http://www.wada-ama.org/rtecontent/document/ 2006_LIST.pdf, (8 February 2007, World Anti-Doping Agency, Montreal, Canada)).…”

Section: Introductionmentioning

confidence: 99%

“…Both free testosterone and conjugated forms appear in plasma and serum [1]. In urine, glucuronide and sulfate conjugates of testosterone dominate over the intact form.…”

Section: Introductionmentioning

confidence: 99%

“…In urine, glucuronide and sulfate conjugates of testosterone dominate over the intact form. Normally, the presence of free testosterone in human urine is nearly irrelevant [1,5]. Testosterone in urine is commonly analyzed as free form after enzymatic hydrolysis of the glucuronide conjugates [6][7][8][9].…”

Section: Introductionmentioning

confidence: 99%

“…After a successful hydrolysis reaction, the concentration of testosterone in male urine is approximately 30-60 mg/L [7,10]. However, age, race [11], circadian rhythm [1] and many diseases affect the excretion of testosterone, and the concentration may vary widely between samples.…”

Section: Introductionmentioning

confidence: 99%

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Microscale immunoaffinity SPE and MEKC in fast determination of testosterone in male urine

et al. 2007

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Conventional methods for the determination of testosterone in body fluids typically suffer from poor recovery, lack of specificity, complex sample pretreatment, or the need for derivatization. Here, a simple, specific, and fast analysis method for testosterone was developed, with a methodology based on testosterone-specific immunoaffinity SPE (IA-SPE) and subsequent analysis by partial filling MEKC (PF-MEKC). An immunosorbent consisting of a recombinant antitestosterone Fab fragment covalently attached to activated Sepharose was prepared. IA-SPE and PF-MEKC were set up in hyphenated and off-line constructions, and the applicability of the two constructions in analysis of testosterone in male urine was investigated. The results obtained with the hyphenated construction proved to be only indicative of the presence of testosterone. The off-line IA-SPE and PF-MEKC construction, however, was successfully used in the determination of free testosterone in male urine samples after enzymatic hydrolysis of the glucuronide conjugates. Except for the hydrolysis reaction, no sample pretreatment was required. After hydrolysis, the overall analysis time per sample was only 14 min. The off-line IA-SPE and PF-MEKC method proved to be robust, sensitive (LOQ 35 mg/L), and specific, enabling separation of testosterone from four related steroids. Thus, it provides attractive features when compared to traditional methods for determination of testosterone in male urine.

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Section: Introductionmentioning

confidence: 99%

“…Both free testosterone and conjugated forms appear in plasma and serum [1]. In urine, glucuronide and sulfate conjugates of testosterone dominate over the intact form.…”

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

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Microscale immunoaffinity SPE and MEKC in fast determination of testosterone in male urine

et al. 2007

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“…Glucocorticosteroids (GCs) are steroid hormones produced in the zona fasciculata and the reticulate of the adrenal cortex. They are involved in a number of physiological processes, such as stress response, inflammation, immune function, hydroelectrolyte balance, behaviour and reproduction (Nozaki 2001, Schuerholz et al 2007. Cortisol, which is the main GC in cows, can prolong their oestrous cycle (Kanchev et al 1976, Stoebel andMoberg 1982), affect ovulation by inhibition of the LH surge (Suter andSchwartz 1985, Macfarlane et al 2000) and is considered an anti-luteolytic factor in the corpus luteum (CL) (McCracken et al 1999, Lee et al 2007, Komiyama et al 2008.…”

Section: Introductionmentioning

confidence: 99%

Effect of cortisol on neurophysin I/oxytocin and peptidyl glycine-α-amidating mono-oxygenase mRNA expression in bovine luteal and granulosa cells

Ziółkowska¹,

Mlynarczuk²,

Kotwica³

2013

Polish Journal of Veterinary Sciences

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Cortisol stimulates the synthesis and secretion of oxytocin (OT) from bovine granulosa and luteal cells, but the molecular mechanisms of cortisol action remain unknown. In this study, granulosa cells or luteal cells from days 1-5 and 11-15 of the oestrous cycle were incubated for 4 or 8 h with cortisol (1x10 -5 , 1x10 -7 M). After testing cell viability and hormone secretion (OT, progesterone, estradiol), we studied the effect of cortisol on mRNA expression for precursor of OT (NP-I/OT) and peptidyl glycine-α-amidating mono-oxygenase (PGA). The influence of RU 486 (1x10 -5 M), a progesterone receptor blocker and inhibitor of the glucocorticosteroid receptor (GR), on the expression for both genes was tested. Cortisol increased the mRNA expression for NP-I/OT and PGA in granulosa cells and stimulated the expression for NP-I/OT mRNA in luteal cells obtained from days 1-5 and days 11-15 of the oestrous cycle. Expression for PGA mRNA was increased only in luteal cells from days 11-15 of the oestrous cycle. In addition, RU 486 blocked the cortisol-stimulated mRNA expression for NP-I/OT and PGA in both types of cells. These data suggest that cortisol affects OT synthesis and secretion in bovine ovarian cells, by acting on the expression of key genes, that may impair ovary function.

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The use of Liquid Membranes in the Multi‐Resdue Extraction of Stilbenes in a Variety of Biological Matrices and Their Detection with LC‐ES‐MS

Msagati

Nindi

2006

Annali di Chimica

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Supported liquid membrane (SLM) has been used as a sample preparation method in the simultaneous extraction of a mixture of three stilbene compounds in cow's milk, urine, bovine kidney and liver tissues matrices. The stilbene compounds analysed included, dienestrol, diethylstilbestrol and hexestrol. The liquid membrane used for trapping these compounds consisted of 5% tri-n-octylphosphine oxide (TOPO) dissolved in di-n-hexylether/n-undecane (1:1). The extraction efficiencies obtained after enrichment of 1 ng/L stilbenes in variety of biological matrices of milk, urine, liver, kidney and water, ranged from 60 - 70%, 71 - 86%, 69 - 80%, 63 - 7A% and 72 - 93% respectively. The detection limits obtained from urine extraction were 2.1 ng/L, 1.3 ng/L and 3.0 ng/L; from liver and kidney tissues were 2.9 ng/L, 1.6 ng/L and 3.8 ng/L and from milk was 3.2 ng/L, 2.5 ng/L and 4.3 ng/L for hexestrol, dienestrol and diethylstilbestrol respectively.

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Steroid analysis for medical diagnosis

Cited by 88 publications

References 56 publications

Microscale immunoaffinity SPE and MEKC in fast determination of testosterone in male urine

Microscale immunoaffinity SPE and MEKC in fast determination of testosterone in male urine

Effect of cortisol on neurophysin I/oxytocin and peptidyl glycine-α-amidating mono-oxygenase mRNA expression in bovine luteal and granulosa cells

The use of Liquid Membranes in the Multi‐Resdue Extraction of Stilbenes in a Variety of Biological Matrices and Their Detection with LC‐ES‐MS

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