ABSTRACT
BACKGROUND: Uvaria chamae (UC) and Olax subscorpioidea (OS) roots are included in traditional anti-cancer remedies and some studies have identified their chemopreventive/chemotherapeutic potential. This study aimed to identify some cellular/molecular mechanisms underlying such potential and the associated chemical constituents. METHODS: Effect on the viability of cancer cells was assessed using the Alamar Blue assay; ability to modulate oxidative stress was assessed using the 2',7'-dichlorofluorescein diacetate (DCFDA) assay; potential to modulate Nuclear factor erythroid 2-related factor like-2 (Nrf2) activity was assessed in the AREc32 luciferase reporter cell line; and anti-inflammatory effect was assessed using lipopolysaccharide-induced nitric oxide release model in the RAW264.7 cells (Griess Assay). Chemical constituents were identified through liquid chromatography-mass spectrometry (LC-MS). RESULTS: Extracts up to 100 µg/ml were non-toxic or mildly toxic to HeLa, AREc32, PC3 and A549 cells (IC50 > 200 µg/ml). Each extract reduced basal and peroxide-induced levels of reactive oxygen species (ROS) in HeLa cells. OS and UC activated Nrf2, with UC producing nearly four-fold induction. Both extracts demonstrated anti-inflammatory effects. Chamanetin, isochamanetin, isouvaretin, uvaricin I and other compounds were found in U. chamae root extract. CONCLUSION: As Nrf-2 induction, antioxidant and anti-inflammatory activities are closely linked with chemoprevention and chemotherapy of cancers, the roles of these plants in traditional anti-cancer remedies are further highlighted, as is their potential as sources of drug leads.
Subject(s)
Antineoplastic Agents/pharmacology , Doxorubicin/pharmacology , Neoplasms/drug therapy , Olacaceae/chemistry , Plant Extracts/pharmacology , Plant Extracts/therapeutic use , Uvaria/chemistry , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/therapeutic use , Antineoplastic Agents/therapeutic use , Antioxidants/pharmacology , Antioxidants/therapeutic use , Basic-Leucine Zipper Transcription Factors/drug effects , Cell Survival/drug effects , Cells, Cultured/drug effects , Doxorubicin/therapeutic use , Humans , Plant Extracts/chemistry , Plant Roots/chemistry , Plants, Medicinal/chemistry , Streptomyces/chemistryABSTRACT
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.
Subject(s)
Designer Drugs/pharmacology , Hallucinogens/pharmacology , Lysergic Acid Diethylamide/analogs & derivatives , Lysergic Acid Diethylamide/pharmacology , Quinolines/pharmacology , Animals , Behavior, Animal/drug effects , Chromatography, Liquid , Designer Drugs/chemistry , Gas Chromatography-Mass Spectrometry , Hallucinogens/blood , Hallucinogens/chemistry , Lysergic Acid Diethylamide/blood , Lysergic Acid Diethylamide/chemistry , Magnetic Resonance Spectroscopy , Male , Mice , Mice, Inbred C57BL , Prodrugs , Quinolines/blood , Quinolines/chemistry , Spectrophotometry, Infrared , Tandem Mass SpectrometryABSTRACT
Three biflavonoids [cupressuflavone (1), amentoflavone (2), and sumaflavone (3)], four diterpenoids [13-epi-cupressic acid (4), imbricatholic acid (5), 3-hydroxy-sandaracopimaric acid (6), and dehydroabietic acid (7)], and one lignan [ß-peltatin methyl ether (8)] were isolated from the cytotoxic fractions of the extracts of the leaves of the Libyan Juniperus phoenicea L. The structures of these compounds were elucidated by spectroscopic means. Cytotoxicity of compounds 1-6 were assessed against the human lung cancer cell line A549 using the MTT assay. Compounds 1 and 3 showed cytotoxicity against the A549 cells (IC50 = 65 and 77 µM, respectively), whereas compound 2 did not show any activity. Diterpenes 4-6 exhibited weak cytotoxicity against the A549 cells with the IC50 values of 159, 263, and 223 µM, respectively. The cytotoxicity of each compound was compared with the anticancer drug, etoposide (IC50 = 61 µM). Cupressuflavone (1) was evaluated also for cytotoxicity against both the human PC3 cancer cell line and the normal prostate cell line (PNT2), and this compound revealed a high degree of cytotoxic selectivity towards the prostate cancer cells (PC3), with IC50 value of 19.9 µM, without any evidence of cytotoxicity towards the normal prostate cell line (PNT2).
Subject(s)
Antineoplastic Agents, Phytogenic/chemistry , Antineoplastic Agents, Phytogenic/therapeutic use , Biflavonoids/chemistry , Diterpenes/chemistry , Juniperus/chemistry , Neoplasms/drug therapy , Plant Leaves/chemistry , HumansABSTRACT
BACKGROUND: Asparagus adscendens Roxb. (Asparagaceae), is native to the Himalayas. This plant has been used in the prevention and effective treatment of various forms of cancers. OBJECTIVE: This paper reports, for the first time, on the cytotoxicity of the methanol (MeOH) extract of the roots of A. adscendens and its solid-phase extraction (SPE) fractions against four human carcinoma cell lines and LC-ESI-QTOF-MS analysis of the SPE fractions. MATERIALS AND METHODS: Finely powdered roots of A. adscendens were macerated in methanol and extracted through SPE using gradient solvent system (water: methanol) proceeded for analysis on LC-ESI-QTOF-MS and cytotoxicity against four human carcinoma cell lines: breast (MCF7), liver (HEPG2), lung (A549), and urinary bladder (EJ138), using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide assay. RESULTS: The MeOH extract and four SPE fractions exhibited cytotoxicity against all cell lines with the IC50 values ranging from 6 to 79 µg/mL. As observed in other Asparagus species, the presence of saponins and sapogenins in the SPE fractions was evident in the liquid chromatography-mass spectrometry data. CONCLUSION: It is reasonable to assume that the cytotoxicity of the MeOH extract of the roots of A. adscendens and its SPE fractions, at least partly, due to the presence of saponins and their aglycones. This suggests that A. adscendens could be exploited as a potential source of cytotoxic compounds with putative anticancer potential. SUMMARY: The MeOH extract and all solid-phase extraction (SPE) fractions exhibited various levels of cytotoxicity against all cell lines with the IC50 values ranging from 6 to 79 µg/mLThe presence of saponins and sapogenins in the SPE fractions was evident in the Liquid chromatography-mass spectrometry dataDue to the presence of saponins and their aglycones, suggest that A. adscendens could be exploited as a potential source of cytotoxic compounds with putative anticancer potential. Abbreviation used: SPE: Solid-phase extraction, MCF7: Breast cancer cell line, HEPG2: Liver cancer cell line, A549: Lung liver cancer cell line, EJ138: Urinary bladder cancer cell line, MTT: 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide, LC-MS: Liquid chromatography-mass spectrometry.
ABSTRACT
Fast-dissolving oral films (FDFs) provide an alternative approach to increase consumer acceptance by advantage of rapid dissolution and administration without water. Usually, FDFs require taste-masking agents. However, inclusion of these excipients could make developing the formulation a challenging task. Hence, this work employed fused-deposition modeling three-dimensional printing to produce single-layered FDFs (SLFDFs), or multilayered FDFs (MLFDFs) films, with taste-masking layers being separated from drug layer. Filaments were prepared containing polyethylene oxide (PEO) with ibuprofen or paracetamol as model drugs at 60°C. Also, filaments were produced containing polyvinyl alcohol and paracetamol at 130°C. Furthermore, a filament was prepared containing PEO and strawberry powder for taste-masking layer. FDFs were printed at temperatures of 165°C (PEO) or 190°C (polyvinyl alcohol) with plain or mesh designs. High-performance liquid chromatography and mass spectroscopy analysis indicated active ingredient stability during film preparation process. SLFDFs had thicknesses as small as 197 ± 21 µm, and MLFDFs had thicknesses starting from 298 ± 15 µm. Depending on the formulation and design, mesh SLFDFs presented disintegration time as short as 42 ± 7 s, and this was 48 ± 5 s for mesh MLFDFs. SLFDFs showed drug content uniformity in the range of 106.0%-112.4%. In conclusion, this study provides proof-of-concept for the manufacturing of FDFs by using 3D printing.
Subject(s)
Acetaminophen/chemistry , Ibuprofen/chemistry , Administration, Oral , Chemistry, Pharmaceutical/methods , Excipients/chemistry , Flavoring Agents/chemistry , Polyethylene Glycols/chemistry , Polyvinyl Alcohol/chemistry , Printing, Three-Dimensional , Solubility , Technology, Pharmaceutical/methods , TemperatureABSTRACT
Antimalarials can interact with heme covalently, by πâ â â π interactions or by hydrogen bonding. Consequently, the prototropy of 4-aminoquinolines and quinoline methanols was investigated by using quantum mechanics. Calculations showed mefloquine protonated preferentially at the piperidine and was impeded at the endocyclic nitrogen because of electronic rather than steric factors. In gas-phase calculations, 7-substituted mono- and bis-4-aminoquinolines were preferentially protonated at the endocyclic quinoline nitrogen. By contrast, compounds with a trifluoromethyl substituent on both the 2- and 8-positions, reversed the order of protonation, which now favored the exocyclic secondary amine nitrogen at the 4-position. Loss of antimalarial efficacy by CF3 groups simultaneously occupying the 2- and 8-positions was recovered if the CF3 group occupied the 7-position. Hence, trifluoromethyl groups buttressing the quinolinyl nitrogen shifted binding of antimalarials to hematin, enabling switching from endocyclic to the exocyclic N. Both theoretical calculations (DFT calculations: B3LYP/BS1) and crystal structure of (±)-trans-N1 ,N2 -bis-(2,8-ditrifluoromethylquinolin-4-yl)cyclohexane-1,2-diamine were used to reveal the preferred mode(s) of interaction with hematin. The order of antimalarial activity in vivo followed the capacity for a redox change of the iron(III) state, which has important implications for the future rational design of 4-aminoquinoline antimalarials.
Subject(s)
Antimalarials/chemistry , Quinolines/chemistry , Aminoquinolines/chemistry , Animals , Antimalarials/pharmacology , Antimalarials/therapeutic use , Crystallography, X-Ray , Drug Design , Electron Spin Resonance Spectroscopy , Ferric Compounds/chemistry , Halogenation , Hemin/chemistry , Hemin/metabolism , Hydrogen Bonding , Isomerism , Locomotion/drug effects , Magnetic Resonance Spectroscopy , Malaria/drug therapy , Malaria/parasitology , Malaria/pathology , Mice , Molecular Conformation , Oxidation-Reduction , Plasmodium berghei/drug effects , Plasmodium berghei/pathogenicity , Quinolines/pharmacology , Quinolines/therapeutic use , ThermodynamicsABSTRACT
RATIONALE: The lipid peroxidation product malondialdehyde forms M1 dG adducts with guanine bases in genomic DNA. The analysis of these adducts is important as a biomarker of lipid peroxidation, oxidative stress and inflammation which may be linked to disease risk or exposure to a range of chemicals. METHODS: Genomic DNA samples were subjected to acid hydrolysis to release the adducts in the base form (M1 G) alongside the other purines. A liquid chromatography/mass spectrometry method was optimised for the quantitation of the M1 G adducts in genomic DNA samples using product ion and multiple reaction monitoring (MRM) scans. RESULTS: Product ion scans revealed four product ions from the precursor ion; m/z 188 â 160, 133, 106 and 79. The two smallest ions have not been observed previously and optimisation of the method revealed that these gave better sensitivity (LOQ m/z 79: 162 adducts per 107 nucleotides; m/z 106: 147 adducts per 107 nucleotides) than the other two ions. An MRM method gave similar sensitivity but the two smallest product ions gave better accuracy (94-95%). Genomic DNA treated with malondialdehyde showed a linear dose-response relationship. CONCLUSIONS: A fast reliable sample preparation method was used to release adducts in the base form rather than the nucleoside. The methods were optimised to selectively analyse the adducts in the presence of other DNA bases without the need for further sample clean-up. Analysis of genomic DNA gave results consistent with previous work and was applied to new samples. Thus, the method is suitable for the analysis of M1 (d)G adducts in biological samples. Copyright © 2017 John Wiley & Sons, Ltd.
Subject(s)
Chromatography, Liquid/methods , DNA Adducts/chemistry , Guanine/analysis , Malondialdehyde/analysis , Tandem Mass Spectrometry/methods , Animals , Cattle , DNA/chemistry , DNA Adducts/analysis , Limit of Detection , Linear Models , Reproducibility of ResultsABSTRACT
Trillium govanianum Wall. (Melanthiaceae alt. Trilliaceae), commonly known as 'nag chhatri' or 'teen patra', is a native species of the Himalayas. It is used in various traditional medicines containing both steroids and sex hormones. In folk medicine, the rhizomes of T. govanianum are used to treat boils, dysentery, inflammation, menstrual and sexual disorders, as an antiseptic and in wound healing. With the only exception of the recent report on the isolation of a new steroidal saponin, govanoside A, together with three known steroidal compounds with antifungal property from this plant, there has been no systematic pharmacological and phytochemical work performed on T. govanianum. This paper reports, for the first time, on the cytotoxicity of the methanol extract of the roots of T. govanianum and its solid-phase extraction (SPE) fractions against four human carcinoma cell lines: breast (MCF7), liver (HEPG2), lung (A549) and urinary bladder (EJ138), using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide cytotoxicity assay and liquid chromatography and electrospray ionization quadrupole time-of-flight mass spectrometry analysis of the SPE fractions. The methanol extract and all SPE fractions exhibited considerable levels of cytotoxicity against all cell lines, with the IC50 values ranging between 5 and 16 µg/mL. Like other Trillium species, presence of saponins and sapogenins in the SPE fractions was evident in the liquid chromatography mass spectrometry data. Copyright © 2016 John Wiley & Sons, Ltd.
Subject(s)
Breast/drug effects , Liver/drug effects , Lung/drug effects , Plant Extracts/chemistry , Plant Roots/chemistry , Trillium/chemistry , Urinary Bladder/drug effects , HumansABSTRACT
The rise in new psychoactive substances that are available as 'research chemicals' (RCs) remains a significant forensic and legislative challenge. A number of arylcyclohexylamines have attracted attention as RCs and continue to be encountered, including 3-MeO-PCP, 3-MeO-PCE and 3-MeO-PCPr. These compounds are commonly perceived as ketamine-like dissociative substances and are believed to act predominantly via antagonism of the N-methyl-D-aspartate (NMDA) receptor. To aid in the identification of newly emerging substances of abuse, the current studies were performed. The syntheses of fifteen N-alkyl-arylcyclohexylamines are described. Analytical characterizations were performed via gas chromatography and high performance liquid chromatography coupled to multiple forms of mass spectrometry as well as nuclear magnetic resonance spectroscopy, ultraviolet diode array detection and infrared spectroscopy. The series consisted of the N-alkyl derivatives (N-methyl, N-ethyl, N-propyl) of phenyl-substituted and isomeric 2-, 3- and 4-methoxy phenylcyclohexylamines, as well as the N-alkyl derivatives obtained from 3-methylphenyl and 2-thienyl moieties. In addition to the presentation of a range of previously unreported data, it was also found that positional isomers of aryl methoxyl-substituted arylcyclohexylamines were readily distinguishable under a variety of analytical conditions. Copyright © 2015 John Wiley & Sons, Ltd.
Subject(s)
Cyclohexylamines/chemistry , Illicit Drugs/chemistry , Psychotropic Drugs/chemistry , Alkylation , Chromatography, Gas , Cyclohexylamines/chemical synthesis , Humans , Illicit Drugs/chemical synthesis , Magnetic Resonance Spectroscopy , Mass Spectrometry , Methylation , Psychotropic Drugs/chemical synthesis , Substance Abuse Detection , Thiophenes/chemical synthesis , Thiophenes/chemistryABSTRACT
RATIONALE: Substances based on the N-(2-methoxybenzyl)phenethylamine template ('NBOMe' derivatives) play an important role in medicinal research but some of these derivatives have also appeared as 'research chemicals' for recreational use which has attracted attention worldwide. A major challenge associated with newly emerging substances includes the lack of analytical data and the ability to correctly identify positional isomers. METHODS: Six N-benzylphenethylamines based on the 2,5-dimethoxy-4-iodophenethylamine structure ('25I') and twelve substituted N-benzyl-5-methoxytryptamines ('5MT') have been prepared and extensively characterized. Techniques used for characterization were gas chromatography/ion trap mass spectrometry in electron and chemical ionization mode, liquid chromatography/diode array detection (DAD), infrared spectroscopy, electrospray high mass accuracy quadrupole time-of-flight tandem mass spectrometry, and triple quadrupole tandem mass spectrometry. RESULTS: The characterization of 18 'NBOMe' compounds provided a comprehensive collection of chromatographic and spectral data. Four groups of three positional isomers, i.e. 25I-NB2OMe, 25I-NB3OMe, 25I-NB4OMe, 25I-NB2B, 25I-NB3B, 25I-NB4B and their 5-methoxytryptamine counterparts, were included and assessed for ability to obtain differentiation. Six meta-substituted N-benzyl derivatives of 5-methoxytryptamine (CF3, F, CH3, Cl, I, SCH3) were also studied. CONCLUSIONS: The implementation of mass spectral techniques was helpful for the differentiation between isomers, for example, when considering the difference in a number of ion ratios. This was considered beneficial in cases where chromatographic separation was only partially achieved under liquid chromatography (LC) conditions. The use of LC/DAD analysis was also found to be valuable for this particular purpose, which confirmed the integrative value of complementary techniques used in areas related to forensic toxicology.
Subject(s)
5-Methoxytryptamine/analysis , 5-Methoxytryptamine/chemistry , Phenethylamines/analysis , Phenethylamines/chemistry , Chromatography, High Pressure Liquid , Gas Chromatography-Mass Spectrometry/methods , Isomerism , Models, Molecular , Tandem Mass SpectrometryABSTRACT
Substances with the diphenylethylamine nucleus represent a recent addition to the product catalog of dissociative agents sold as 'research chemicals' on the Internet. Diphenidine, i.e. 1-(1,2-diphenylethyl)piperidine (1,2-DEP), is such an example but detailed analytical data are less abundant. The present study describes the synthesis of diphenidine and its most obvious isomer, 1-(2,2-diphenylethyl)piperidine (2,2-DEP), in order to assess the ability to differentiate between them. Preparation and characterization were also extended to the two corresponding pyrrolidine analogues 1-(1,2-diphenylethyl)- and 1-(2,2-diphenylethyl)pyrrolidine, respectively. Analytical characterizations included high-resolution electrospray mass spectrometry (HR-ESI-MS), liquid chromatography ESI-MS/MS, gas chromatography ion trap electron and chemical ionization MS, nuclear magnetic resonance spectroscopy (NMR) and infrared spectroscopy. Differentiation between the two isomeric pairs was possible under GC-(EI/CI)-MS conditions and included the formation of distinct iminium ions, such as m/z 174 for 1,2-DEP and m/z 98 for 2,2-DEP, respectively. The pyrrolidine counterparts demonstrated similar phenomena including the expected mass difference of 14 Da due to the lack of one methylene unit in the ring. Two samples obtained from an Internet vendor provided confirmation that diphenidine was present in both samples, concurring with the product label. Finally, it was confirmed that diphenidine (30 µM) reduced N-methyl-D-aspartate-mediated field excitatory postsynaptic potentials (NMDA-fEPSPs) to a similar extent to that of ketamine (30 µM) when using rat hippocampal slices. The appearance of 1,2- diphenylethylamines appears to reflect the exploration of alternatives to arylcyclohexylamine-type substances, such as methoxetamine, PCP and PCPy-based analogues that also show NMDA receptor activity as demonstrated here for diphenidine.
Subject(s)
Chemistry Techniques, Analytical/methods , Excitatory Postsynaptic Potentials/drug effects , Piperidines/chemical synthesis , Piperidines/pharmacology , Pyrrolidines/chemistry , Animals , Excitatory Postsynaptic Potentials/physiology , Female , Hippocampus/drug effects , Hippocampus/physiology , Isomerism , Ketamine/pharmacology , Male , RatsABSTRACT
The application of the inkjet method to pharmaceutical products is promising. To make this realistic, not only does the throughput of this method need to be increased, but also the components should be inert to pharmaceutical preparations. We present designs of glass-based inkjet devices that are capable of producing droplets at high rates. To achieve this, inkjet devices from glass capillary tubes were manufactured with orifice diameters of 5, 10 and 20 µm and were actuated with diaphragm piezoelectric disks. Also, a pressure capsule was formed by creating a manifold at a distance from the orifice tip. Placing the piezoelectric disk at 0.5 mm distance from the tip allowed the formation of a jet at 3.2 MHz in certain designs, but for a short period of time because of overheating. The length of the pressure capsule, its inlet diameter, and the nozzle tip geometry were crucial to lower the required power. Actuating an inkjet device with 10 µm orifice diameter comfortably at 900 kHz and drying the droplets from 1% salbutamol sulphate solution allowed the formation of particles with diameters of 1.76 ± 0.15 µm and the geometric standard deviation of 1.08. In conclusion, optimising internal design of glass inkjet devices allowed the production of high-throughput droplet ejectors.
Subject(s)
Albuterol/chemistry , Glass , High-Throughput Screening Assays/instrumentation , Printing/instrumentation , Technology, Pharmaceutical/instrumentation , Calorimetry, Differential Scanning , Chemistry, Pharmaceutical , Crystallization , Crystallography, X-Ray , Equipment Design , Particle Size , Powder Diffraction , Pressure , ThermogravimetryABSTRACT
During the second half of 2013, a total of 26 deaths involving para-methyl-4-methylaminorex (4,4'-DMAR) were reported to the European Monitoring Centre for Drugs and Drug Addiction. While aminorex and 4-methylaminorex (4-MAR) are known psychostimulants, nothing is known about the comparatively new para-methyl analog. Analytical characterization of two independent samples obtained from online vendors confirmed the presence of the (±)-cis isomer that also appeared to be associated with at least 18 of the 26 deaths. Extensive characterizations included crystal structure analysis, single, tandem, and high-resolution mass spectrometry, liquid and gas chromatography, and nuclear magnetic resonance spectroscopy. For the work described here, both the (±)-cis and (±)-trans racemates were also synthesized, confirming that the differentiation between these two forms was straight-forward. Monoamine transporter activity was studied using rat brain synaptosomes which included the comparison with d-amphetamine, aminorex and (±)-cis-4-MAR. (±)-cis-4,4'-DMAR was a potent, efficacious substrate-type releaser at transporters for dopamine, norepinephrine and serotonin with EC50 values of 8.6 ± 1.1 nM (DAT), 26.9 ± 5.9 nM (NET) and 18.5 ± 2.8 nM (SERT), respectively. The potency of (±)-cis-4,4'-DMAR at DAT and NET rivalled that of other psychomotor stimulant drugs like d-amphetamine and aminorex. However, (±)-cis-4,4'-DMAR had much more potent actions at SERT and activity at SERT varied more than 100-fold across the four drugs. The potent releasing activity of (±)-cis-4,4'-DMAR at all three monoamine transporters predicts a potential for serious side-effects such as psychotic symptoms, agitation, hyperthermia and cardiovascular stimulation, especially after high-dose exposure or following combination with other psychostimulants.