Follicle stimulating hormone international standards and reference preparations for the calibration of immunoassays and bioassays

Effects of exposure to volatile organic compounds (VOCs) content from paint on automobile paint workers in Nsukka, South Eastern Nigeria

Background

Volatile organic compounds (VOCs) fume in the workplace can act as an inducing agent to many health disorders.

Objectives

This work investigated the effects of exposure to VOCs content from paint on the automobile paint workers in South Eastern Nigeria.

Methods

A total of fifty (50) respondent participated in the study. Following the completion of informed consent form and well-structured questionnaire, blood samples were drawn and used for biochemical analysis.

Results

The results of the haematological analysis showed a significant (p < 0.05) increase in white blood cell (WBC) cluster of differentiation 4 (CD4), and platelet (PLT), and a significant (p < 0.05) decrease in packed cell volume (PCV), hemoglobin (HB), lymphocytes (LYM) and eosinophil (EOS) of the exposed automobile paint workers compared to the control (unexposed workers). Results also showed significant (p < 0.05) increase in liver marker indices; alanine transaminase (ALT), aspartate transaminase (AST), total bilirubin (TB) and albumin (ALB) as well as significant (p < 0.05) decrease in Alkaline phosphatase (ALP), total protein (TP), direct bilirubin (DB). There was significant (p < 0.05) increase in urea, creatinine, potassium (K+), uric acid and nitric oxide concentrations and decrease in sodium (Na+) and bicarbonate (HCO3-) Again, results showed significant increase in Glutathione (GSH), and Glutathione peroxidase (GPx) and significant (p < 0.05) decrease in Superoxide dismutase (SOD) and Catalase (CAT). The Malondialdehyde MDA concentration showed varied significant (p < 0.05) difference based on ages. There was significant (p < 0.05) increase in luteinizing hormone (LH) and Follicle stimulating hormone (FSH), and significant (p < 0.05) decrease in the Testosterone (TET) concentrations of the exposed automobile paint workers compared to the unexposed workers.

Conclusions

Result of this study suggests a toxic outcome due to exposure to VOCs in spray paint workers.

The effects of saline water consumption on sperm parameters, testicular histopathology, hormonal and antioxidants concentrations in Barki Rams

The study aimed to assess the effects of water salinity on the sperm parameters, levels of cortisol, LH, FSH, testosterone and antioxidants as well as the testes' histopathology in Barki rams. Fifteen healthy Barki rams (1-1.5 years) were divided into three equal depending on the type of drinking water for nine months. The rams in the tap water group (TW, water that contained 350 ppm of total dissolved salts (TDS). Males in the high saline water group (HSW) were permitted to consume high saline water with 8,934 ppm TDS, whereas those in the second group were permitted to have moderately saline water (MSW, 4,557 ppm TDS). High salt concentration in drinking water had adverse effect on sperm viability, morphology and sperm cell concertation. Nitric oxide and malondialdehyde concentrations in blood were significantly higher in the MSW and HSW groups than in TW. There was a significant decrease in glutathione concentration as well as superoxide dismutase activity in TDS and HSW. Cortisol was most highly concentrated in the HSW, next in the MSW, and least in TW. The testosterone, LH, and FSH concentrations in the HSW and MSW groups were significantly lower than in TW. As the salt concentration in drinking water increases, damage to testicular tissue. The MSW group demonstrating vacuolation of lining epithelial cells with pyknotic nuclei in the epididymis and necrosis and desquamation of spermatogenic cells in seminiferous tubules while HSW group displaying desquamated necrotic cells and giant cell formation in the epididymis, as well as damage to some of the seminiferous tubules and showed congestion, vacuolation of spermatogenic epithelium of seminiferous tubules, and desquamated necrotic spermatogenic epithelium. In conclusion, the salinity of the water has detrimental impacts on the sperm morphology, viability and concentration, hormones and antioxidant levels in Barki rams.

Treatment of Inactive Ovaries of Holstein Dairy Cows by Epidural Injection of GnRH Analogue (Receptal) and Its Impact on the Reproductive Hormones, Oxidant/Antioxidant Profile and Micro and Macro-Elements Profile

This study was designed to evaluate a new therapeutic approach for inactive ovaries based on the epidural administration of a GnRH agonist (Receptal) and an investigation of the impact of this treatment on the hormonal, oxidant/antioxidant and micro- and macro-element profiles. Sixty cows with postpartum anestrus were divided into two groups: the first group (group R_epid, n = 30) was administered an epidural injection of Receptal, while the second group (group C_epid, n = 30) received saline and was considered the control group. Evaluation of hormonal (progesterone, FSH, LH, testosterone, and cortisol), oxidant/antioxidant (MDA, SOD, GPx and TAC) as well as micro- and macroelement (calcium, phosphorus, manganese and magnesium) profiles was done in serum. The results showed that the epidural injection of Receptal has the potential to induce estrus response and conception incidence in treated cows. Compared to the control group, progesterone, FSH, and LH concentrations were significantly increased in the treated group, whereas testosterone and cortisol decreased (p < 0.05) following treatment. In addition, the treated group had greater TAC and GPx concentrations than the control group. Serum concentrations of magnesium increased (p < 0.05) following receptal treatment, but differences in other minerals were not detected. This research suggests a novel, effective method of treating inactive ovaries with epidural infusion of a GnRH agonist.

IFCC Working Group Recommendations for Correction of Bias Caused by Noncommutability of a Certified Reference Material Used in the Calibration Hierarchy of an End-User Measurement Procedure

Establishing metrological traceability to an assigned value of a matrix-based certified reference material (CRM) that has been validated to be commutable among available end-user measurement procedures (MPs) is central to producing equivalent results for the measurand in clinical samples (CSs) irrespective of the clinical laboratory MPs used. When a CRM is not commutable with CSs, the bias due to noncommutability will be propagated to the CS results causing incorrect metrological traceability to the CRM and nonequivalent CS results among different MPs. In a commutability assessment, a conclusion that a CRM is commutable or noncommutable for use with a specific MP is made when the difference in bias between the CRM and CSs meets or does not meet a criterion for that specific MP when compared to other MPs. A conclusion regarding commutability or noncommutability requires that the magnitude of the difference in bias observed in the commutability assessment remains unchanged over time. This conclusion requires the CRM to be stable and no substantive changes in the MPs. These conditions should be periodically reverified. If an available CRM is determined to be noncommutable for a specific MP, that CRM can be used in the calibration hierarchy for that MP when an appropriately validated MP-specific correction for the noncommutability bias is included. We describe with examples how a MP-specific correction and its uncertainty can be developed and applied in a calibration hierarchy to achieve metrological traceability of results for CSs to the CRM's assigned value.

Cadmium Exposure and Ovarian Reserve in Women Aged 35-49 Years: The Impact on Results From the Creatinine Adjustment Approach Used to Correct for Urinary Dilution

Cadmium is toxic to the ovaries in animal studies, but its association with diminished ovarian reserve in women is not established. We investigated urinary cadmium, a biomarker of long-term exposure, in relation to diminished ovarian reserve, as indicated by elevated serum follicle-stimulating hormone concentrations (≥10 IU/L), in women aged 35-49 years (unweighted n = 1,681). Using data from the Third National Health and Nutrition Examination Survey (1988-1994), we conducted Poisson regression to estimate adjusted relative risks and 95% confidence intervals. Because the best approach to correcting for urinary dilution in spot samples with creatinine remains controversial, we employed 3 approaches: standardization, covariate adjustment, and covariate-adjusted standardization. Our data suggested a modest association with standardization (highest quartile vs. lowest: relative risk (RR) = 1.3, 95% confidence interval (CI): 0.8, 1.9; P for trend = 0.06) and covariate-adjusted standardization (highest quartile vs. lowest: RR = 1.3, 95% CI: 0.9, 1.9; P for trend = 0.05) and a stronger association with covariate adjustment (highest quartile vs. lowest: RR = 1.8, 95% CI: 1.2, 2.9; P for trend = 0.01). The stronger association with covariate adjustment may reflect bias from conditioning on urinary creatinine, a collider in the hypothesized causal pathway. We conclude that cadmium may contribute to ovarian aging in women and that careful consideration of the creatinine adjustment approach is needed to minimize bias.

Antiapoptotic and antioxidant capacity of phytochemicals from Roselle (Hibiscus sabdariffa) and their potential effects on monosodium glutamate-induced testicular damage in rat

Monosodium glutamate (MSG), common flavor enhancer and feed additive, causes male reproductive dysfunction. However, Roselle tea, popular Hibiscus sabdariffa (HS) beverage, has a controversial effectiveness on male fertility. Therefore, the current study aimed to investigate either the adverse effect of aqueous HS extract (HSE) on the testicle or its potential ameliorative role including some stress markers, biochemical and immunohistochemical expressions in rats subjected to MSG. Here, the animals were divided into four groups that were given distilled water, HSE, MSG, and HSE + MSG respectively via gavage. After 6 weeks from the beginning of experiment, blood samples were collected for hormonal analysis. Additionally, testicular specimens were excised and processed for oxidative/antioxidant parameters determination, histological examination, and immunohistochemical evaluation of Bax and PCNA positive spermatogenic cells. Preliminary phytochemical analyses as well as antioxidant capacity of the HSE were tested. Our results revealed a strong inhibitory activity of the HSE phytochemical constituents against DPPH radical. MSG group revealed a significant decrease of testosterone, LH, FSH, and antioxidant parameters with elevated MDA compared with control and HSE groups. Additionally, an alteration of the testicular histo-architecture was observed among MSG group along with increased Bax and decreased PCNA positive cells. Meanwhile, the HSE showed a potent protective effect against testicular damage as well as oxidative stress induced by MSG. On the whole, our findings provide evidence that HSE can ameliorate MSG-induced testicular toxicity via induction of cell proliferation along with reduction of oxidative stress and cellular apoptosis in adult rat that attributed to the antioxidant and antiapoptotic effects of its phytochemical constituents.

Clomiphene citrate ameliorated lead acetate-induced reproductive toxicity in male Wistar rats

Objective:

The current study investigated the effects of clomiphene citrate on the hypothalamic-pituitary-testicular axis, steroidogenesis, sperm parameters, and testicular antioxidant enzyme activity of male Wistar rats submitted to lead acetate (Pb)-induced reproductive toxicity.

Methods:

Twenty adult male Wistar rats were divided into four groups of equal size as follows: Control; Clomid (0.35 mg/kg); Pb (10 mg/kg); and Clomid + Pb. Serum levels of follicle stimulating hormone (FSH), luteinizing hormone (LH), testosterone, testicular 17-β hydroxysteroid dehydrogenase (17-β HSD) activity, androgen receptors, catalase activity, superoxide dismutase (SOD), malondialdehyde (MDA), sperm motility, viability, counts and morphology were estimated after oral administration of Clomid and/or lead acetate for 35 consecutive days. Data were analyzed using ANOVA at p<0.05.

Results:

Lead acetate significantly decreased (p<0.05) serum LH and testosterone levels, testicular 17β-HSD activity, androgen receptor expression, sperm motility, viability, counts, catalase activity, and SOD when compared with controls. Abnormal sperm morphology and MDA were significantly increased (p<0.05) in the Pb group compared with controls. Clomid co-administrated with lead acetate significantly increased (p<0.05) serum LH, testosterone levels, testicular 17β-HSD, androgen receptor expression, sperm motility and viability when compared with the group given lead acetate.

Conclusions:

The present study suggests that clomiphene citrate may stimulate testicular testosterone synthesis, sperm motility and viability via luteinizing hormone in a context of lead acetate-induced reproductive toxicity.

The roadmap for harmonization: status of the International Consortium for Harmonization of Clinical Laboratory Results

The International Consortium for Harmonization of Clinical Laboratory Results (ICHCLR) was established to fulfill recommendations identified by an international conference convened to review the available infrastructure and challenges in achieving harmonization of results among different measurement procedures. The specific objectives of the ICHCLR are to: prioritize measurands by medical importance, coordinate the work of different organizations, and stimulate development of technical and regulatory processes to achieve harmonization. Central to these objectives is the website “www.harmonization.net” developed by the ICHCLR as an information portal designed to provide a resource center for global activities to harmonize and standardize results from clinical laboratory measurement procedures. Priorities based on medical impact are provided for measurands for which harmonization is needed or work to implement harmonization is incomplete or inactive. By making information available regarding harmonization activities in progress or planned, coordination of work to harmonize laboratory measurement procedures will minimize duplication of effort and optimize the use of limited resources. A toolbox of technical procedures developed by ICHCLR to be considered when developing a process to achieve harmonization for a measurand is presented. The ICHCLR initiated a proposal to ISO Technical Committee 212 for a harmonization protocol as the basis for calibration traceability when there are no other higher order reference system components available. The ICHCLR offers a unique service to prioritize measurands in need of harmonization and to provide a centralized approach to organize global efforts to achieve harmonization of clinical laboratory test results.

Current practices and challenges in the standardization and harmonization of clinical laboratory tests

Effective patient care, clinical research, and public health efforts require comparability of laboratory results independent of time, place, and measurement procedure. Comparability is achieved by establishing metrological traceability, which ensures that measurement procedures measure the same quantity and that the calibration of measurement procedures is traceable to a common reference system consisting of reference methods and materials. Whereas standardization ensures traceability to the International System of Units, harmonization ensures traceability to a reference system agreed on by convention. This article provides an overview of standardization and harmonization with an emphasis on commutability as an important variable that affects testing accuracy. Commutability of reference materials is required to ensure that traceability is established appropriately and that laboratory results are comparable. The use of noncommutable reference materials leads to inaccurate results. Whereas procedures and protocols for standardizing measurements are established and have been successfully applied in efforts such as the Hormones Standardization Program of the CDC, harmonization activities require new, more complex procedures and approaches. The American Association for Clinical Chemistry, together with its domestic and international partners, formed the International Consortium for Harmonization of Clinical Laboratory Results to coordinate harmonization efforts. Reference systems, as well as procedures and protocols to establish traceability of clinical laboratory tests, have been established and continue to be developed by national and international groups and organizations. Serum tests of thyroid function, including those for the thyroid hormones thyroxine and triiodothyronine, are among the clinical procedures for which standardization efforts are well under way. Approaches to the harmonization of measurement procedures for serum concentrations of thyroid-stimulating hormone are likewise under development.

Standardization of hormone determinations

Standardization of hormone determinations is important because it simplifies interpretation of results and facilitates the use of common reference values for different assays. Progress in standardization has been achieved through the introduction of more homogeneous hormone standards for peptide and protein hormones. However, many automated methods for determinations of steroid hormones do not provide satisfactory result. Isotope dilution-mass spectrometry (ID-MS) has been used to establish reference methods for steroid hormone determinations and is now increasingly used for routine determinations of steroids and other low molecular weight compounds. Reference methods for protein hormones based on MS are being developed and these promise to improve standardization.

Standardization of therapeutic, urinary gonadotrophins: an update on the use and availability of International Standards for Menotrophin

The potencies of therapeutic preparations of gonadotrophins of human, urinary origin, which comprise a heterogenous mix of isoforms with follicle-stimulating hormone (FSH) and luteinizing hormone (LH) bioactivities, are standardized by WHO International Standards (IS). We report here, the evaluation, through an international collaborative study, of a candidate preparation, coded 10/286, to replace the 4th IS, 98/704, for human, urinary FSH and LH (Menotrophin) which has been used for many years for the potency assignment of therapeutic preparations using bioassays. The mean FSH and LH bioactivities of 10/286, determined by in vivo bioassays in terms of 98/704, were 183 IU per ampoule (95% confidence limits 165-202) and 177 IU per ampoule (95% confidence limits 159-197), respectively.

Roadmap for harmonization of clinical laboratory measurement procedures

Results between different clinical laboratory measurement procedures (CLMP) should be equivalent, within clinically meaningful limits, to enable optimal use of clinical guidelines for disease diagnosis and patient management. When laboratory test results are neither standardized nor harmonized, a different numeric result may be obtained for the same clinical sample. Unfortunately, some guidelines are based on test results from a specific laboratory measurement procedure without consideration of the possibility or likelihood of differences between various procedures. When this happens, aggregation of data from different clinical research investigations and development of appropriate clinical practice guidelines will be flawed. A lack of recognition that results are neither standardized nor harmonized may lead to erroneous clinical, financial, regulatory, or technical decisions. Standardization of CLMPs has been accomplished for several measurands for which primary (pure substance) reference materials exist and/or reference measurement procedures (RMPs) have been developed. However, the harmonization of clinical laboratory procedures for measurands that do not have RMPs has been problematic owing to inadequate definition of the measurand, inadequate analytical specificity for the measurand, inadequate attention to the commutability of reference materials, and lack of a systematic approach for harmonization. To address these problems, an infrastructure must be developed to enable a systematic approach for identification and prioritization of measurands to be harmonized on the basis of clinical importance and technical feasibility, and for management of the technical implementation of a harmonization process for a specific measurand.

Standardization of FSH, LH and hCG--current position and future prospects

Gonadotropin measurements contribute significantly to patient management in both endocrinology and oncology. Differences in calibration, antibody specificities and assay design mean that gonadotropin results obtained in different methods are still not comparable. Comparing patient results obtained in different methods therefore remains problematic, whether for individual patient care, when assessing the results of multicentre clinical trials, or when formulating national and international guidelines and recommendations. Achieving improved comparability of results for these important analytes will require clear descriptive nomenclature, accurate calibration with highly purified standards, careful characterization of what gonadotropin isoforms methods are measuring, broad recommendations about the most clinically appropriate antibody combinations, and increased awareness of clinically relevant interferences and the action required to minimise their effect. Encouraging manufacturers to standardize and carefully describe the evaluation methods they use, such that data from different manufacturers can readily be compared, is also a pre-requisite for future progress.

Analysis of intact human follicle-stimulating hormone preparations by reversed-phase high-performance liquid chromatography

A reversed-phase high-performance liquid chromatography (RP-HPLC) method for the qualitative and quantitative analysis of intact human follicle-stimulating hormone (hFSH) was established and validated for accuracy, precision and sensitivity. Human FSH is a dimeric glycoprotein hormone widely used as a diagnostic analyte and as a therapeutic product in reproductive medicine. The technique developed preserves the protein integrity, allowing the analysis of the intact heterodimeric form rather than just of its subunits, as is the case for the majority of the conditions currently employed. This methodology has also been employed for comparing the relative hydrophobicity of pituitary, urinary and two Chinese hamster ovary (CHO)-derived hFSH preparations, as well as of two other related glycoprotein hormones of the anterior pituitary: human thyroid-stimulating hormone (hTSH) and human luteinizing hormone (hLH). The least hydrophobic of the three glycohormones analyzed was hFSH, followed by hTSH and hLH. A significant difference (p<0.005) was observed in t(R) between the pituitary and recombinant hFSH preparations, reflecting structural differences in their carbohydrate moieties. Two main isoforms were detected in urinary hFSH, including a form which was significantly different (p<0.005) from the pituitary and recombinant preparations. The linearity of the dose-response curve (r=0.9965, n=15) for this RP-HPLC methodology, as well as an inter-assay precision of less than 4% for the quantification of different hFSH preparations and a sensitivity of the order of 40 ng, were demonstrated. The chromatographic behaviour and relative hydrophobicity of the individual subunits of the pituitary and recombinant preparations were also analyzed. Furthermore, the molecular mass of individual hFSH subunits and of the heterodimer were simultaneously determined by matrix-assisted laser desorption ionization time-of-flight mass spectral analysis (MALDI-TOF-MS). The present methodology represents, in our opinion, an essential tool for the characterization and quality control of this hormone, that is not yet described in the main pharmacopoeias.

Molecular architecture and biorecognition processes of the cystine knot protein superfamily: part I. The glycoprotein hormones

In this review article, the reader is introduced to recent advances in our knowledge on a subset of the cystine knot superfamily of homo- and hetero-dimeric proteins, from the perspective of the endocrine glycoprotein hormone family of proteins: follitropin (FSH), Iutropin (LH), thyrotropin. (TSH) and chorionic gonadotropin (CG). Subsequent papers will address the structure-function behaviour of other members of this increasingly significant family of proteins, including various members of the transforming growth factor-beta (TGF-beta) family of proteins, the activins, inhibins, bone morphogenic growth factor, platelet derived growth factor-beta, nerve growth factor and more than 35 other proteins with similar topological features. In the present review article, specific emphasis has been placed on advances with the glycoprotein hormones (GPHs) that have facilitated greater insight into their physiological functions, molecular structures and most importantly the basis of the molecular recognition events that lead to the formation of hetero-dimeric structures as well as their specific and selective recognition by their corresponding receptors and antibodies. Thus, this review article focuses on the structural motifs involved in receptor recognition and the current techniques available to identify these regions, including the role of immunological methodology, peptide fragment design and synthesis and mutagenesis to delineate their structure-function relationships and molecular recognition behaviour.

Definition and measurement of follicle stimulating hormone

FSH has a key role in the development and function of the reproductive system and is widely used both diagnostically and therapeutically in developmental and reproductive medicine. The accurate measurement of FSH levels, in patients for diagnosis and monitoring and in therapeutic preparations for clinical use, is essential for safe and successful treatment. Historically, FSH was defined on the basis of classical in vivo endocrine activity, and early therapeutic preparations were calibrated using in vivo bioassays. There was early recognition that reference preparations were required for calibration if the results from different laboratories were to be comparable. In response to the perceived need, the World Health Organization established the first standard for such preparations in 1959. Subsequent developments in biotechnology have led to recognition that there is no single molecule that can be uniquely defined as FSH, and that FSH can induce a range of biological activities. Several highly purified standards for FSH are now available, but discontinuity and heterogeneity of estimates of FSH activity in terms of these standards made using in vitro assays and binding assays have been noted. It is thus essential that any measurement of FSH include specification both of the standard with which the measured FSH is compared and the assay method used for that comparison.