421 research outputs found
Multianalyte LC-MS-based methods in doping control: what are the implications for doping athletes?
Over the last 50 years, the list of doping
substances and methods has been progressively
expanding, being regularly reviewed
by the international antidoping authorities
(formerly the Medical Commission of the
International Olympic Committee, and afterward,
following its constitution in 1999, the
World Anti-Doping Agency [WADA]). New
substances/classes of substances have been
periodically included in the list, keeping the
pace with more advanced and sophisticated
doping trends. At present, and apart from
the prohibited performance enhancing and
masking methods (e.g., blood transfusions
and tampering strategies), the list comprises
several hundreds of biologically active substances,
with broad differences in their physicochemical
properties (i.e., molecular weight,
polarity and acid-basic properties) [1]. As a
consequence, the ‘one class – one procedure’
approach, which had been followed by nearly
all accredited antidoping laboratories worldwide
until the turn of the millennium, is no
longer sustainable. The need to minimize the
overall number of independent analytical procedures,
and, in parallel, to reduce the analytical
costs, stimulated the development of multitargeted
methods, aimed to increase the overall
ratio of ‘target analytes: procedure’ [2–6].
The above evolution has not always been
a straight forward process. The need to comply
with the WADA technical requirements
(both in terms of identification criteria and of
minimum required performance limits [7,8])
and with the reduction of the reporting time
(a constraint that becomes even more critical
during international sport events, where
the daily workload also drastically increases)
has imposed a thorough re-planning of the
analytical procedures.
The development of an antidoping analytical
method requires the appropriate knowledge
not only of the biophysicochemical
properties of the target analyte, but also of its
PK profile. Historically, immunological methods
and GC-based techniques were applied
in antidoping science, as preferential screening
methods for the detection of prohibited
substances, which were originally limited to
nonendogenous stimulants and narcotics. In
the 1980s, GC–MS became the reference analytical
platform for the detection and quantification
of the majority of the low molecular
weight doping substances [3–6]. In the following
two decades, with the inclusion in the
Prohibited List of new classes of low molecular
weight, hydrophilic, thermolabile, nonvolatile
analytes (including, but not limited to, glucocorticoids
and designer steroids) and simultaneously
of peptide hormones, scientists were
obliged to design, develop, validate and apply
techniques based on LC–MS/MS
Toxicity testing in environmental monitoring: The role of enzymatic biosensors
Biological toxicity testing is a rapidly expanding field involving numerous bioanalytical techniques. The enzymatic biosensors are valuable screening tools to identify pollutants and/or toxic agents in the environment and/or in food matrices, thus representing a valid alternative to animal testing in analytical toxicology. Inhibition based biosensors here presented have been proved to represent alternative assays for the toxicity evaluation of warfare agents and endocrine disrupting chemicals as well as algal toxins (phycotoxins) in the contamined sea foods (mainly clams and other mollusks). Results obtained by inhibition studies performed by means of several enzymatic biosensors indicate the reliability of the proposed method and the possibility to extend such an experimental approach to other toxicants as a simple, rapid and cheap biotest, to be used easily also "on the spot"
The body language of caste : Marathi sexual modernity (1920-1950)
Late colonial Maharashtra witnessed a proliferation of sex literature that claimed to be scientific. Sexual-health journals and books on sexual science and eugenics, as well as marriage manuals insisting on sex reforms, were produced in Marathi in considerable numbers between 1920 and 1950. Why did sex reformism blossom in Maharashtra? What was reformed in the name of sex and science? What larger purpose did this writing serve in late colonial times? The present research work answers these questions while problematising the Marathi sexual modernity articulated through this literature. In critically assessing sex reforms, my argument highlights the rearrangement of an inextricable nexus between caste and sexuality that shaped late colonial Marathi expressions of modernity. The proliferation of scientific sexuality in this process, I argue, was an upper-caste resolution of the Brahminical crisis over dominating reformism in Maharashtra. To demonstrate this, my work situates sex literature in the context of Marathi caste politics. While explaining the Brahminical crisis and its resolution through analysing sexual discourses of brahmacharya (celibacy), marriage, and obscenity, this work unpacks the making of sex reforms as a journey to create a caste-sexual subject of Marathi modernity—the respectable upper-caste man
Ecdysteroids: A novel class of anabolic agents?
Increasing numbers of dietary supplements with ecdysteroids are marketed as “natural anabolic agents”. Results of recent studies suggested that their anabolic effect is mediated by estrogen receptor (ER) binding. Within this study the anabolic potency of ecdysterone was compared to well characterized anabolic substances. Effects on the fiber sizes of the soleus muscle in rats as well the diameter of C2C12 derived myotubes were used as biological readouts. Ecdysterone exhibited a strong hypertrophic effect on the fiber size of rat soleus muscle that was found even stronger compared to the test compounds metandienone (dianabol), estradienedione (trenbolox), and SARM S 1, all administered in the same dose (5 mg/kg body weight, for 21 days). In C2C12 myotubes ecdysterone (1 µM) induced a significant increase of the diameter comparable to dihydrotestosterone (1 µM) and IGF 1 (1.3 nM). Molecular docking experiments supported the ERβ mediated action of ecdysterone. To clarify its status in sports, ecdysterone should be considered to be included in the class “S1.2 Other Anabolic Agents” of the list of prohibited substances of the World Anti-Doping Agency
Determination of Endogenous and Synthetic Glucocorticoids in Human Urine by Gas Chromatography – Mass Spectrometry Following Microwave Assisted Derivatization
Acomplete screening and confirmation analytical method for the direct determination of six endogenous (cortisol, cortisone, deoxycorticosterone, tetrahydrocortisol, tetrahydrocortisone, tetrahydro-S) and 17 synthetic (amcinonide, betamethasone, desoximethasone, dexamethasone, fludrocortisone, flumethasone, flunisolide, flucinolone acetonide, flucinonide, fluprednisolone, flurandrenolide, fluorometholone, 6-methylprednisolone, prednisolone, prednisone, triamcinolone, triamcinolone acetonide) glucocorticoids in human urine by gas chromatography with mass spectrometric detection (GC–MS) is presented. The analytical technique comprises a pre treatment procedure and the instrumental analysis of the trimethylsilyl (TMS) derivatives, performed by GC–MS (quadrupole) with electron impact (EI) ionization. The derivatization yields obtained by two different derivatizing mixtures, namely N-methyl N(trimethylsilyl)trifluoroacetamide (MTSFA):NH4I:dithioerythritol (DTE) 1000:2:4 (usually indicated as TMSiodine); and N-trimethylsilylimidazole (TMSim):N,O-bis(trimethylsilyl)acetamide (BSA):trimethylchlorosilane (TMCS) 3:3:2, both under direct thermal heating and with microwave (MW) irradiation, were evaluated, also as a function of the temperature, of the MWì power and of the incubation time. The highest yields of the derivatization process were obtained, for most of the compounds here considered, by a two-step procedure: a microwave-assisted derivatization stage (40 min in a microwave oven at 900Wemitted power), followed by a traditional heat transfer derivatization (1.5 h in a thermostated bath at 70 ◦C) with the derivatization mixture TMSim:BSA:TMCS 3:3:2. In these operating conditions, diagnostic EI–MS spectra of all considered glucocorticoids were obtained. Limits of detection (LOD) of synthetic glucocorticoids in urine ranged from 3 to 25g/l. The effectiveness of the method for the determination of glucocorticoids in urine was evaluated on spiked urine samples and on real samples obtained from patients
under pharmacological treatment with synthetic glucocorticoids. Apart from the clinical monitoring of glucocorticoids in urine, the method can be applied as a complete screening + confirmation analytical protocol in antidoping tests for the detection of illicit administration of glucocorticoids by the athletes
Applying total interpretive structural modeling to study factors affecting construction labour productivity
Construction sector has always been dependent on manpower. Most of the activities carried out on any construction site are labour intensive. Since productivity of any project depends directly on productivity of labour, it is a prime responsibility of the employer to enhance labour productivity. Measures to improve the same depend on analysis of positive and negative factors affecting productivity. Major attention should be given to factors that decrease the productivity of labour. Factor analysis thus is an integral part of any study aiming to improve productivity. Interpretive structural modeling is a methodology for identifying and summarizing relationships among factors which define an issue or problem. It provides a means to arrange the factors in an order as per their complexity. This study attempts to use the latest version of interpretive structural modeling i.e. total interpretive structural modeling to analyze factors negatively affecting construction labour productivity. It establishes interpretive relationship among these factors facilitating improvement in the overall productivity of construction site
Advanced Voting Machine with Secutiry Features
Voting is most pivotal process of democratic society through which people determine its government. Governments around the world are increasingly considering the replacement of traditional paper-based voting schemes with electronic voting systems. Here we are designing a fully secured voting machine using smart card. The voter’s identification is done by a ‘Smart Memory Card’ which contain the voters ID. As soon as the voter inserts the card in the smart card reader, the microcontroller will check and then allow the voter to vote. The microcontroller will also check for duplicate voting. If duplicate card is detected buzzer is turned ON and voting is locked. The microcontroller will count the votes and store in its internal memory. When the result button is pressed, the microcontroller will display the voting result on LCD. If any malpractice/Booth capturing is observed then the administrator can press the reset button which will lock the voting machine and further voting is suspended
Determination of clenbuterol in human urine by GC-MS-MS-MS: confirmation analysis in antidoping control
This work presents a GC-MS-MS-MS method for the direct determination of clenbuterol in human urine. The method comprises a pretreatment procedure and the instrumental analysis of the derivatives performed by GC-MS3 (ion trap) with electron impact ionization. The GC-MS3 analysis allows isolation and characterization of specific fragments from the original (MS1) molecular structure, and in particular, those fragments originating from the precursor ion cluster (m/z = 335-337) characteristic of clenbuterol. The MS2 product fragment m/z = 300 is in turn used as a further precursor fragment giving rise to a MS3 spectrum specific for clenbuterol. MS4 fragmentation spectra were also investigated. However, further fragmentation of MS3 product ions does not lead to functional MS4 spectra nor to any significant increase in the signal-to-noise ratio. The sensitivity limit of the MS3 technique is lower than 0.2 mug/l, with a linear range between 0.5 and 5 mug/l, thus matching the basic requirements for antidoping analysis according to the guidelines of the International Olympic Committee. Due to its overall analytical performance, the method is presently being evaluated as a confirmation protocol to be followed to detect illicit clenbuterol administration to the athletes, and compared with reference GC-MS and GC-MS-MS techniques. (C) 2002 Elsevier Science B.V. All rights reserved
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