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1.
The definition of the temporal sequence of appearance of fetal markers during prenatal and early postnatal development in Sertoli and germ cells may be important for understanding the mechanisms underlying their reexpression in disorders of the adult testis. For this reason, we studied the expression of Sertoli and germ cell markers in 25 human testes spanning a period from 8 gestational weeks to 4 years. Well-characterized antibodies were employed to anti-Müllerian hormone (AMH), cytokeratin 18 (CK18), vimentin (VIM), M2A-antigen (M2A), germ cell alkaline phosphatase (GCAP), and somatic angiotensin-converting enzyme (sACE) on formalin-fixed and microwave-pretreated paraffin sections. In Sertoli cells, AMH and VIM were consistently present. While VIM and CK18 were coexpressed in embryonic testes, CK18 was progressively downregulated and completely absent from the 20th gestational week. M2A was absent or moderately expressed in fetal Sertoli cells but increased during further development. In germ cells, M2A was consistently found in primordial germ cells (PGCs) as well as in M- and T1-prespermatogonia. In contrast, sACE and GCAP were absent from PGCs but were a distinct feature of late M- and early T1-prespermatogonia and appeared predominantly between the 18th and the 22nd gestational weeks. Both T2-prespermatogonia and postnatal prespermatogonia were devoid of any marker. While CK18 represents a differentiation marker for fetal Sertoli cells, M2A, GCAP, and sACE can be used as differentiation markers for the discrimination of different germ cell types during human prespermatogenesis. Because various immunophenotypes reflect distinct differentiation stages, this knowledge may be important for understanding adult testicular pathology. 相似文献
2.
Simon D. Brandt Pierce V. Kavanagh Folker Westphal Alexander Stratford Simon P. Elliott Geraldine Dowling Adam L. Halberstadt 《Drug testing and analysis》2020,12(10):1514-1521
Recent investigations have shown that N‐ethyl‐N‐cyclopropyl lysergamide (ECPLA) produces LSD‐like behavioral effects in mice, which suggests that it may act as a hallucinogen in humans. Although the use of ECPLA as a recreational drug has been limited, key analytical data that can be used to detect ECPLA are required for future forensic and clinical investigations. ECPLA is an isomer of (2′S,4′S)‐lysergic acid 2,4‐dimethylazetidide (LSZ), a lysergamide that emerged as a recreational drug in 2013. Several analytical approaches were examined, including single‐ and tandem mass spectrometry platforms at low and high resolution, gas‐ and liquid chromatography (GC, LC), nuclear magnetic resonance spectroscopy (NMR), and GC condensed‐phase infrared spectroscopy (GC‐sIR). ECPLA and LSZ could be differentiated by NMR, GC‐sIR, GC, and LC‐based methods. The electron ionization mass spectra of ECPLA and LSZ contained ion clusters typically observed with related lysergamides such as m/z 150–155, m/z 177–182, m/z 191–197, m/z 205–208, and m/z 219–224. One of the significant differences in abundance related to these clusters included ions at m/z 196 and m/z 207/208. The base peaks were detected at m/z 221 in both cases followed by the retro‐Diels‐Alder fragment at m/z 292. Minor but noticeable differences between the two isomers could also be seen in the relative abundance of m/z 98 and m/z 41. Electrospray ionization mass spectra included lysergamide‐related ions at m/z 281, 251, 223, 208, 197, 180, and 140. LSZ (but not ECPLA) showed product ions at m/z 267 and m/z 98 under the conditions used. 相似文献
3.
Simon D. Brandt Pierce V. Kavanagh Folker Westphal Alexander Stratford Anna U. Odland Adam K. Klein Geraldine Dowling Nicola M. Dempster Jason Wallach Torsten Passie Adam L. Halberstadt 《Drug testing and analysis》2020,12(6):812-826
Lysergic acid diethylamide (LSD) is a prototypical serotonergic psychedelic drug and the subject of many clinical investigations. In recent years, a range of lysergamides has emerged with the production of some being inspired by the existing scientific literature. Others, for example various 1‐acyl substituted lysergamides, did not exist before their appearance as research chemicals. 1‐Cylopropanoyl‐LSD (1CP‐LSD) has recently emerged as a new addition to the group of lysergamide‐based designer drugs and is believed to be psychoactive in humans. In this investigation, 1CP‐LSD was subjected to detailed analytical characterizations including various mass spectrometry (MS) platforms, gas and liquid chromatography, nuclear magnetic resonance spectroscopy, solid phase and GC condensed phase infrared spectroscopy. Analysis by GC–MS also revealed the detection of artificially induced degradation products. Incubation of 1CP‐LSD with human serum led to the formation of LSD, indicating that it may act as a prodrug for LSD in vivo, similar to other 1‐acyl substituted lysergamides. The analysis of blotters and pellets is also included. 1CP‐LSD also induces the head‐twitch response (HTR) in C57BL/6 J mice, indicating that it produces an LSD‐like behavioural profile. 1CP‐LSD induced the HTR with an ED50 = 430.0 nmol/kg which was comparable to 1P‐LSD (ED50 = 349.6 nmol/kg) investigated previously. Clinical studies are required to determine the potency and profile of the effects produced by 1CP‐LSD in humans. 相似文献
4.
Bjoern Moosmann Philippe Bisel Folker Westphal Maurice Wilde Jürgen Kempf Verena Angerer Volker Auwrter 《Drug testing and analysis》2019,11(3):541-549
The number of newly appearing benzodiazepine derivatives on the new psychoactive substances (NPS) drug market has increased over the last couple of years totaling 23 ‘designer benzodiazepines’ monitored at the end of 2017 by the European Monitoring Centre for Drugs and Drug Addiction. In the present study, three benzodiazepines [flunitrazolam, norflurazepam, and 4′‐chlorodiazepam (Ro5–4864)] offered as ‘research chemicals' on the Internet were characterized and their main in vitro phase I metabolites tentatively identified after incubation with pooled human liver microsomes. For all compounds, the structural formula declared by the vendor was confirmed by gas chromatography?mass spectrometry (GC–MS), liquid chromatography?tandem mass spectrometry (LC MS/MS), liquid chromatography?quadrupole time of flight?mass spectrometry (LC?QTOF?MS) analysis and nuclear magnetic resonance (NMR) spectroscopy. The metabolic steps of flunitrazolam were monohydroxylation, dihydroxylation, and reduction of the nitro function. The detected in vitro phase I metabolites of norflurazepam were hydroxynorflurazepam and dihydroxynorflurazepam. 4’‐Chlorodiazepam biotransformation consisted of N‐dealkylation and hydroxylation. It has to be noted that 4′‐chlorodiazepam and its metabolites show almost identical LC–MS/MS fragmentation patterns to diclazepam and its metabolites (delorazepam, lormetazepam, and lorazepam), making a sufficient chromatographic separation inevitable. Sale of norflurazepam, the metabolite of the prescribed benzodiazepines flurazepam and fludiazepam, presents the risk of incorrect interpretation of analytical findings. 相似文献
5.
All deleterious changes in platelet morphology, structure and function that occur in platelet concentrates (PC) during storage are titled as the 'platelet storage lesion'. No single in?vitro test currently available is sufficient in assessing these changes of platelet quality. The release of soluble CD40 Ligand (sCD40L), the formation of thromboxane (TXB2) and the thrombopoietin (TPO) clearance reflect different aspects of platelet metabolism and activitiy, and were used to examine platelet quality in apheresis platelet products. At days 1, 3 and 5, in single-donor apheresis platelet products (n?=?10) under routine storage conditions, sCD40L (measured by ELISA) and TXB2 (measured by RIA) were determined after platelet stimulation (recalcification and clot formation). TPO (measured by ELISA) was determined after an incubation time of 5?h at 37°C with platelet-rich plasma (adjusted initial TPO concentration of about 500?pg/mL). Results were related to a therapeutic unit (TU?=?2?×?10(11)?platelets). Immediately after platelet preparation, sCD40L release was 41?±?7.6?ng/TU, TXB2 formation 1688?±?374?ng/TU and TPO clearance 1.22?±?0.32?ng/h/TU. At days 1, 3 and 5, sCD40L was reduced to 89?±?7%, 71?±?12% and 57?±?9%, TXB2 release to 91?±?6%, 74?±?12% and 58?±?9% and TPO clearance to 90?±?15%, 84?±?5% and 79?±?10% of the respective control values. In conclusion, in single-donor apheresis PC, sCD40L release and TXB2 formation as well as TPO clearance by the platelets were dependent on storage duration and reduced to about 60% to 80% of the respective control values after a storage period for 5 days. These findings are in line with literature data, indicating that a loss of platelet functionality of about 30% will occur after 5 days of storage. 相似文献
6.
7.
Return of the lysergamides. Part IV: Analytical and pharmacological characterization of lysergic acid morpholide (LSM‐775)
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Simon D. Brandt Pierce V. Kavanagh Brendan Twamley Folker Westphal Simon P. Elliott Jason Wallach Alexander Stratford Landon M. Klein John D. McCorvy David E. Nichols Adam L. Halberstadt 《Drug testing and analysis》2018,10(2):310-322
Lysergic acid diethylamide (LSD) is perhaps one of the best‐known psychoactive substances and many structural modifications of this prototypical lysergamide have been investigated. Several lysergamides were recently encountered as ‘research chemicals’ or new psychoactive substances (NPS). Although lysergic acid morpholide (LSM‐775) appeared on the NPS market in 2013, there is disagreement in the literature regarding the potency and psychoactive properties of LSM‐775 in humans. The present investigation attempts to address the gap of information that exists regarding the analytical profile and pharmacological effects of LSM‐775. A powdered sample of LSM‐775 was characterized by X‐ray crystallography, nuclear magnetic resonance spectroscopy (NMR), gas chromatography mass spectrometry (GC–MS), high mass accuracy electrospray MS/MS, high performance liquid chromatography (HPLC) diode array detection, HPLC quadrupole MS, and GC solid‐state infrared analysis. Screening for receptor affinity and functional efficacy revealed that LSM‐775 acts as a nonselective agonist at 5‐HT1A and 5‐HT2A receptors. Head twitch studies were conducted in C57BL/6J mice to determine whether LSM‐775 activates 5‐HT2A receptors and produces hallucinogen‐like effects in vivo. LSM‐775 did not induce the head twitch response unless 5‐HT1A receptors were blocked by pretreatment with the antagonist WAY‐100,635 (1 mg/kg, subcutaneous). These findings suggest that 5‐HT1A activation by LSM‐775 masks its ability to induce the head twitch response, which is potentially consistent with reports in the literature indicating that LSM‐775 is only capable of producing weak LSD‐like effects in humans. 相似文献
8.
Synthesis,analytical characterization,and monoamine transporter activity of the new psychoactive substance 4‐methylphenmetrazine (4‐MPM), with differentiation from its ortho‐ and meta‐ positional isomers
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Gavin McLaughlin Michael H. Baumann Pierce V. Kavanagh Noreen Morris John D. Power Geraldine Dowling Brendan Twamley John O'Brien Gary Hessman Folker Westphal Donna Walther Simon D. Brandt 《Drug testing and analysis》2018,10(9):1404-1416
The availability of new psychoactive substances (NPS) on the recreational drug market continues to create challenges for scientists in the forensic, clinical and toxicology fields. Phenmetrazine (3‐methyl‐2‐phenylmorpholine) and an array of its analogs form a class of psychostimulants that are well documented in the patent and scientific literature. The present study reports on two phenmetrazine analogs that have been encountered on the NPS market following the introduction of 3‐fluorophenmetrazine (3‐FPM), namely 4‐methylphenmetrazine (4‐MPM), and 3‐methylphenmetrazine (3‐MPM). This study describes the syntheses, analytical characterization, and pharmacological evaluation of the positional isomers of MPM. Analytical characterizations employed various chromatographic, spectroscopic, and mass spectrometric platforms. Pharmacological studies were conducted to assess whether MPM isomers might display stimulant‐like effects similar to the parent compound phenmetrazine. The isomers were tested for their ability to inhibit uptake or stimulate release of tritiated substrates at dopamine, norepinephrine and serotonin transporters using in vitro transporter assays in rat brain synaptosomes. The analytical characterization of three vendor samples revealed the presence of 4‐MPM in two of the samples and 3‐MPM in the third sample, which agreed with the product label. The pharmacological findings suggest that 2‐MPM and 3‐MPM will exhibit stimulant properties similar to the parent compound phenmetrazine, whereas 4‐MPM may display entactogen properties more similar to 3,4‐methylenedioxymethamphetamine (MDMA). The combination of test purchases, analytical characterization, targeted organic synthesis, and pharmacological evaluation of NPS and their isomers is an effective approach for the provision of data on these substances as they emerge in the marketplace. 相似文献
9.
Adam P. Vogel Sophie E. Brown Joanne E. Folker Louise A. Corben Martin B. Delatycki 《Journal of neurology》2014,261(2):392-399
Dysphagia in Friedreich ataxia (FRDA) and its impact on quality of life is not adequately understood. The objective of this study was to characterise dysphagia in FRDA and to determine the impact of swallowing dysfunction on activities, participation, and sense of well-being. Thirty-six individuals with a confirmed diagnosis of FRDA were assessed via a clinical bedside examination (CBE), the Royal Brisbane Hospital outcome measure for swallowing, an oral-motor examination and the Australian therapy outcome measures for speech and swallowing (AusTOMS). Data on swallowing function, diet modification and swallowing strategies were collated. Thirty-three (91.67 %) participants exhibited clinical signs of dysphagia according to the CBE, and all participants received ratings indicating swallowing difficulties on at least one other measure. Dysphagia in FRDA is characterised by oral and pharyngeal stage impairment relating to incoordination, weakness and spasticity. A significant positive correlation was found between the severity of impairment, activity, participation and distress/well-being on the AusTOMS, suggesting that swallowing function decreases with overall reductions in quality of life. A significant correlation was found between activity on the AusTOMS and disease duration (r = ?0.283, p = 0.012). No significant correlations were found between dysphagia severity and GAA repeat length, age of onset or disease severity. Participants employing diet modification and swallowing strategies demonstrated higher dysphagia severity, activity limitations and participation restrictions. These data advocate a holistic approach to dysphagia management in FRDA. Early detection of swallowing impairment and consideration of the potential impact dysphagia has on quality of life should be key aspects in disease management. 相似文献
10.