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1.
Drug Test Anal ; 15(5): 484-494, 2023 May.
Article in English | MEDLINE | ID: mdl-36605020

ABSTRACT

Carfentanil is one of the most potent synthetic opioids ever developed, with an estimated analgesic potency approximately 20-100 times that of fentanyl and 10,000 times that of morphine. Carfentanil has been appearing in the illicit drug supply in many regions and has been linked to fatal overdose events. A subset of 59 street drug samples obtained in Victoria, B.C., that were confirmed to contain carfentanil were analyzed by mass spectrometry for this study. Carfentanil quantitation by paper spray mass spectrometry ranged from 0.05 to 2.95 w/w% (median = 0.32%) in the original drug sample. Paper spray mass spectrometry analysis also detected two unknown peaks at m/z 380.2 and 381.2 in 31 of these 59 samples (53%). Initial tandem mass spectrometry experiments revealed structural similarities between these unknown compounds and carfentanil, suggesting they were potential structural analogs, possibly arising from incomplete purification during synthesis. High-resolution mass spectrometry determined the chemical formulas of these compounds as C23 H29 N3 O2 (m/z 380.2333) and C23 H29 N2 O3 (m/z 381.2137). Literature and tandem mass spectrometry results were used to determine the identity of these potential new psychoactive substances, C23 H29 N3 O2 as desmethylcarfentanil amide and C23 H29 N2 O3 as desmethylcarfentanil acid. µ-Opioid receptor binding modeling determined that the binding poses of these analogs were nearly identical to that of carfentanil with relative binding energy calculations of 0.544 kJ/mol (desmethylcarfentanil amide) and -0.171 kJ/mol (desmethylcarfentanil acid); these data suggest they may share the toxic effects of carfentanil and have similar potencies.


Subject(s)
Illicit Drugs , Fentanyl , Analgesics, Opioid , Tandem Mass Spectrometry , Amides
2.
Rheumatol Ther ; 9(6): 1517-1529, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36125701

ABSTRACT

INTRODUCTION: The Routine Assessment of Patient Index Data 3 (RAPID3) is a patient-reported outcome tool recommended for the assessment of disease activity in patients with rheumatoid arthritis (RA) in clinical practice. This analysis evaluated the long-term effect of upadacitinib vs. comparators on RAPID3 scores in patients with RA in the phase 3 SELECT clinical trial program. METHODS: This post hoc analysis included data from five randomized controlled trials (RCTs) in patients receiving upadacitinib 15 mg or 30 mg once daily (QD) as monotherapy or in combination with conventional synthetic disease-modifying antirheumatic drugs (csDMARDs). The proportions of patients reporting RAPID3 remission (scores ≤ 3) were assessed at week 60. Correlations between absolute scores for RAPID3 and Clinical Disease Activity Index (CDAI), Simplified Disease Activity Index (SDAI), and 28-joint Disease Activity Score with C-reactive protein (DAS28[CRP]) at week 60 were assessed using Spearman correlation coefficients. RESULTS: A total of 3117 patients were included from the SELECT-NEXT, -BEYOND, -MONOTHERAPY, -COMPARE, and -EARLY trials. By week 60, 32-52% of methotrexate-naïve and csDMARD inadequate responder (IR) patients treated with either upadacitinib 15 mg QD or upadacitinib 30 mg QD reported RAPID3 scores consistent with remission. The proportions were slightly lower in the biologic DMARD-IR SELECT-BEYOND population (19-28%). RAPID3 scores highly correlated (Spearman correlation values ≥ 0.58) with CDAI, SDAI, and DAS28(CRP) scores through week 60 (all p < 0.001). CONCLUSIONS: Upadacitinib, as monotherapy or in combination with csDMARDs, was associated with patient-reported remission assessed by RAPID3 over 60 weeks across the SELECT RCTs in patients with RA. TRIAL REGISTRATION: SELECT-BEYOND (NCT02706847); SELECT-NEXT (NCT02675426); SELECT-MONOTHERAPY (NCT02706951); SELECT-EARLY (NCT02706873); SELECT-COMPARE (NCT02629159).


Rheumatoid arthritis (RA) is a disease that causes inflammation of the joints. Doctors have several ways of assessing how bad a patient's disease is, and these often use a combination of signs and symptoms to develop a 'score'. One method is called RAPID3, which is a score based on an overall assessment of the disease by the patient, the level of pain, and the amount of physical disability. An advantage of RAPID3 is that it is quick and easy to use, and since it uses only patient-reported symptoms, it can be measured easily via telemedicine, without the need for an in-person consultation. In this study, we decided to look into the effect of upadacitinib, a drug used for the treatment of RA, on RAPID3 score in patients with RA. We also investigated whether RAPID3 correlates with other ways of measuring RA severity, including scores that use physician-measured factors such as number of affected joints, as this can help show whether RAPID3 is a valid and useful tool. We found that upadacitinib led to long-term improvements in RAPID3 score, and that results were the same in different studies and patient groups, including patients who had not responded well to other treatments. We also found that RAPID3 correlated well with other measures, i.e., improvements in RAPID3 happened in parallel with improvements in other scores. Overall, these results suggest that RAPID3 can be a useful tool in patients with RA.

3.
Harm Reduct J ; 19(1): 3, 2022 01 11.
Article in English | MEDLINE | ID: mdl-35012557

ABSTRACT

BACKGROUND: The overdose crisis has generated innovative harm reduction and drug market monitoring strategies. In Toronto, Ontario, Canada, a multi-site drug checking service (DCS) pilot project was launched in October 2019. The project provides people who use drugs with information on the chemical composition of their substances, thereby increasing their capacity to make more informed decisions about their drug use and avoid overdose. DCS also provides real-time market monitoring to identify trends in the unregulated drug supply. METHODS: Sample data were obtained through analyses of drug and used drug administration equipment samples submitted anonymously and free of charge to DCS in downtown Toronto from October 10, 2019, to April 9, 2020, representing the first six months of DCS implementation. Analyses were conducted in clinical laboratories using liquid chromatography- and/or gas chromatography-mass spectrometry (LC-MS, GC-MS) techniques. RESULTS: Overall, 555 samples were submitted, with 49% (271) of samples that were found to contain high-potency opioids, of which 87% (235) also contained stimulants. Benzodiazepine-type drugs were found in 21% (116) of all samples, and synthetic cannabinoids in 1% (7) of all samples. Negative effects (including overdose, adverse health events, and extreme sedation) were reported for 11% (59) of samples submitted for analysis. CONCLUSIONS: Toronto's DCS identified a range of high-potency opioids with stimulants, benzodiazepine-type drugs, and a synthetic cannabinoid, AMB-FUBINACA. This information can inform a range of evidence-informed overdose prevention efforts.


Subject(s)
Drug Overdose , Illicit Drugs , Pharmaceutical Preparations , Analgesics, Opioid , Drug Overdose/prevention & control , Fentanyl , Humans , Laboratories, Clinical , Ontario , Pilot Projects
4.
Harm Reduct J ; 18(1): 104, 2021 10 13.
Article in English | MEDLINE | ID: mdl-34645480

ABSTRACT

BACKGROUND: The North American opioid overdose crisis is driven in large part by the presence of unknown psychoactive adulterants in the dynamic, unregulated drug supply. We herein report the first detection of the psychoactive veterinary compound xylazine in Toronto, the largest urban center in Canada, by the city's drug checking service. METHODS: Toronto's Drug Checking Service launched in October 2019. Between then and February 2021, 2263 samples were submitted for analysis. The service is offered voluntarily at harm reduction agencies that include supervised consumption services. Samples were analyzed using gas chromatography-mass spectrometry or liquid chromatography-high resolution mass spectrometry. Targeted and/or untargeted screens for psychoactive substances were undertaken. RESULTS: In September 2020, xylazine was first detected by Toronto's Drug Checking Service. Among samples analyzed from September 2020 to February 2021 expected to contain fentanyl in isolation (610) or in combination with methamphetamine (16), xylazine was detected in 46 samples (7.2% and 12.5% of samples, respectively). Samples were predominantly drawn from used drug equipment. Three of the samples containing xylazine (6.5%) were associated with an overdose. CONCLUSION: We present the first detection of xylazine in Toronto, North America's fourth-largest metropolitan area. The increased risk of overdose associated with use of xylazine and its detection within our setting highlights the importance of drug checking services in supporting rapid responses to the emergence of potentially harmful adulterants. These data also highlight the clinical challenges presented by the dynamic nature of unregulated drug markets and the concomitant need to establish regulatory structures to reduce their contribution to overdose morbidity and mortality.


Subject(s)
Drug Overdose , Illicit Drugs , Pharmaceutical Preparations , Analgesics, Opioid , Canada , Fentanyl , Humans , Xylazine
5.
BMJ Case Rep ; 12(2)2019 Feb 28.
Article in English | MEDLINE | ID: mdl-30824464

ABSTRACT

Mirror hand is a congenital anomaly characterised by duplication of the ulnar ray, resulting in polydactyly and functional disability of the hand. It can cause arthralgias and weakness in intrinsic muscles of the hand. We present a young woman who had a surgically corrected mirror hand and subsequently developed aggressive rheumatoid arthritis, which increased her limitations to a significant degree. Early diagnosis and treatment in such cases is very important to prevent long-term disability.


Subject(s)
Arthritis, Rheumatoid/diagnostic imaging , Arthritis, Rheumatoid/pathology , Hand Deformities, Congenital/surgery , Adalimumab/therapeutic use , Adult , Antirheumatic Agents/therapeutic use , Arthritis, Rheumatoid/drug therapy , Diagnosis, Differential , Female , Glucocorticoids/therapeutic use , Hand/diagnostic imaging , Hand/surgery , Humans , Hydroxychloroquine/therapeutic use , Methotrexate/therapeutic use , Polydactyly/surgery , Range of Motion, Articular , Treatment Outcome , Ultrasonography
8.
Psychopharmacology (Berl) ; 234(22): 3309-3320, 2017 Nov.
Article in English | MEDLINE | ID: mdl-28825117

ABSTRACT

BACKGROUND: The dopamine D3 receptor (DRD3) has been proposed as a target for drug development for the treatment of addictive disorders. Recently, the anxiolytic buspirone has been shown to have affinity for DRD3 and DRD4, and interest in repurposing it for addictive disorders has grown. METHODS: Binding of [3H]-(+)-PHNO in the rat cerebellum and striatum was used to measure occupancy by buspirone of DRD3 or DRD2, respectively. Effects of buspirone in the rat gambling task (rGT) and the five-choice serial reaction time task (5-CSRTT) were examined. RESULTS: Buspirone occupied both the DRD2 and DRD3 at high doses and the DRD3, but not the DRD2, in the narrow dose range of 3 mg/kg. At 10 mg/kg, a disruption of performance on rGT was observed. All measures of performance on the rGT, except for perseverations, were affected at 3 mg/kg. On the 5-CSRTT, omissions were increased. Impairments in the rGT were not mimicked by the effects induced by satiation. Further, buspirone did not impair food-maintained responding under a progressive ratio schedule of reinforcement at any dose, suggesting that the effects of buspirone on the rGT cannot be explained by non-selective actions. CONCLUSIONS: Although buspirone had effects on the rGT at the dose that selectively occupied the DRD3, the effects found do not parallel those found in previous studies of the effects of selective DRD3 antagonists on the rGT. Thus, buspirone may impair performance on the rGT through actions at multiple receptor sites.


Subject(s)
Disease Models, Animal , Gambling/psychology , Receptors, Dopamine D2/drug effects , Receptors, Dopamine D3/drug effects , Receptors, Dopamine D4/drug effects , Animals , Anti-Anxiety Agents/pharmacology , Behavior, Addictive/psychology , Buspirone/pharmacology , Cerebellum/drug effects , Choice Behavior/drug effects , Corpus Striatum/drug effects , Dose-Response Relationship, Drug , Drug Repositioning , Male , Rats , Rats, Long-Evans , Rats, Sprague-Dawley , Reaction Time/drug effects , Reinforcement, Psychology
10.
Foot (Edinb) ; 30: 53-58, 2017 Mar.
Article in English | MEDLINE | ID: mdl-28262590

ABSTRACT

INTRODUCTION: Rheumatoid arthritis (RA) is one of a number of inflammatory arthropathies resulting in foot pain and deformity. Patients with this disease may require surgical intervention as part of their management. Many of these patients are now taking biologic agents which pose several risks to patients in the perioperative phase. The surgical team therefore need to be aware of these associated complications and how to manage these cases. AIM: This paper aims to review the current literature about perioperative needs (foot and ankle surgery) associated with patients with rheumatoid arthritis receiving biologic therapy. MAIN FINDINGS: The majority of the literature discusses the perioperative complications associated with patients on anti-TNFα therapy with few studies investigating the other biologics in common use. There is conflicting evidence as to the safety of continuing or stopping biologic drug therapy prior to orthopaedic procedures. The British Society for Rheumatology (BSR) have produced guidelines for the management of patients on anti-TNFα therapy or the biologic agent Tocilizumab. These recommendations suggest the risks of post-operative infection need to be balanced against the risk of a post-operative disease flare. In essence, it is suggested anti-TNFα therapy is stopped 3-5 times the half-life of the drug whilst Tocilizumab is stopped 4 weeks prior to surgery. CONCLUSION: Good communication is needed between the surgical team and the local Rheumatology department managing the patient's disease in order to optimise perioperative care. Local pathways may vary from the BSR recommendations to determine the most suitable course of action with regards to continuing or stopping biologic therapy prior to foot and ankle surgery.


Subject(s)
Ankle/surgery , Antirheumatic Agents/therapeutic use , Arthritis, Rheumatoid/drug therapy , Arthritis, Rheumatoid/surgery , Foot/surgery , Antibodies, Monoclonal, Humanized/therapeutic use , Elective Surgical Procedures , Humans , Preoperative Care , Surgical Wound Infection/prevention & control , Tumor Necrosis Factor-alpha/antagonists & inhibitors , Wound Healing/drug effects
11.
Clin Toxicol (Phila) ; 54(1): 61-5, 2016.
Article in English | MEDLINE | ID: mdl-26577583

ABSTRACT

CONTEXT: Solanum torvum berries, known as susumber or turkey berries, are prepared as part of traditional Jamaican dishes usually served with cod and rice. Poisoning is rare. Although toxic compounds have never been definitively isolated, previous reports suggest toxicity results from inhibition of acetylcholinesterases. We present a case of susumber berry poisoning with detailed electromyographic studies and laboratory analysis. CASE DETAILS: A 54-year-old woman presented to the Emergency Department (ED) complaining of vision, speech, and gait changes; emesis; and diffuse myalgias following consumption of susumber berries. The physical examination demonstrated an intact, lucid mental status, miosis, opsoclonus, severe dysarthria, dysmetria, mild extremity tenderness and weakness, and inability to ambulate. Her symptom constellation was interpreted as a stroke. DISCUSSION: Electromyography demonstrated a pattern of early full recruitment as well as myotonia during the period of acute toxicity. Additionally, solanaceous compounds, in particular solasonine and solanidine, were identified in leftover berries and the patient's serum. Store-bought commercial berries and subsequent serum samples were free of such toxic compounds. EMG studies, together with a laboratory analysis of berries or serum can assist in the differential diagnosis of stroke, and provide both a prognostic screening and confirmation of suspected glycoside toxicity.


Subject(s)
Electromyography , Foodborne Diseases/diagnosis , Neurotoxicity Syndromes/diagnosis , Solanaceous Alkaloids/poisoning , Solanum/poisoning , Diosgenin/blood , Diosgenin/poisoning , Female , Foodborne Diseases/blood , Foodborne Diseases/physiopathology , Fruit , Humans , Middle Aged , Neurotoxicity Syndromes/blood , Neurotoxicity Syndromes/etiology , Neurotoxicity Syndromes/physiopathology , Predictive Value of Tests , Solanaceous Alkaloids/blood
12.
Quant Imaging Med Surg ; 4(1): 50-6, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24649435

ABSTRACT

In this work, we propose and investigate a volume coil array design method using different types of birdcage coils for MR imaging. Unlike the conventional radiofrequency (RF) coil arrays of which the array elements are surface coils, the proposed volume coil array consists of a set of independent volume coils including a conventional birdcage coil, a transverse birdcage coil, and a helix birdcage coil. The magnetic fluxes of these three birdcage coils are intrinsically cancelled, yielding a highly decoupled volume coil array. In contrast to conventional non-array type volume coils, the volume coil array would be beneficial in improving MR signal-to-noise ratio (SNR) and also gain the capability of implementing parallel imaging. The volume coil array is evaluated at the ultrahigh field of 7T using FDTD numerical simulations, and the g-factor map at different acceleration rates was also calculated to investigate its parallel imaging performance.

13.
Sex Transm Dis ; 38(6): 528-32, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21233789

ABSTRACT

BACKGROUND: Increasing interest in the use of enzyme immunoassays (EIA) for syphilis screening has generated a considerable need for data on the performance of such tests. METHODS: We compared the performance of 1 EIA, the TREP-SURE EIA to that of the Venereal Disease Research Laboratory (VDRL) and Treponema pallidum particle agglutination assay (TPPA) in the detection of infection with Treponema pallidum. In total, 674 specimens were tested by VDRL and EIA (356 VDRL-nonreactive and 318 VDRL-reactive). All specimens that were found to be reactive by either the VDRL or EIA were subsequently analyzed by TPPA. RESULTS: We found that the TREP-SURE EIA was marginally less sensitive than the VDRL test for screening, but was significantly more specific. All EIA-TPPA discordant specimens were analyzed by multiple tests, including Immunoglobulin M- and G-specific Western blots and an IgM-specific EIA. Signal-to-cutoff ratios (index values) generated by the TREP-SURE EIA were also investigated. It was found that these values may be instructive regarding the interpretation of test results, as they were found to correlate strongly with the probability of positivity on a TPPA assay. Specimens that reacted positively on the EIA with very high index values were found overwhelmingly to be reactive by TPPA, perhaps obviating the need for the testing of most EIA positive specimens with a secondary treponemal test. CONCLUSIONS: An IgM/IgG sensitive EIA would be an effective alternative to VDRL for syphilis screening. Using the EIA index values may provide additional, helpful information to the diagnostic process.


Subject(s)
Immunoenzyme Techniques/methods , Immunoglobulin G/blood , Immunoglobulin M/blood , Mass Screening/standards , Syphilis/diagnosis , Treponema pallidum/immunology , Antibodies, Bacterial/blood , Female , Homosexuality, Male , Humans , Male , Mass Screening/methods , Reagent Kits, Diagnostic , Risk , Sensitivity and Specificity , Syphilis Serodiagnosis
14.
J Acquir Immune Defic Syndr ; 50(5): 546-51, 2009 Apr 15.
Article in English | MEDLINE | ID: mdl-19367993

ABSTRACT

BACKGROUND: It is hypothesized that sexually transmitted diseases (STDs) increase the risk of HIV acquisition. Yet difficulties establishing an accurate temporal relation and controlling confounders have obscured this relationship. In an attempt to overcome prior methodologic shortcomings, we explored the use of different study designs to examine the relationship between STDs and HIV acquisition. METHODS: Acutely HIV-infected patients were included as cases and compared with (1) HIV-uninfected patients (matched case-control), (2) newly diagnosed chronically HIV-infected patients (infected analysis), and (3) themselves at prior clinic visits when they tested HIV negative (case crossover).We used t tests to compare the average number of STDs and logistic regression to determine independent correlates and the odds of acute HIV infection. RESULTS: Between October 2003 and March 2007, 13,662 male patients who had sex with men were tested for HIV infection at San Francisco's municipal STD clinic and 350 HIV infections (2.56%) were diagnosed. Among the HIV-infected patients, 36 cases (10.3%) were identified as acute. We found consistently higher odds of having had an STD within the 12 months [matched case-control, odds ratio 5.2 (2.2-12.6); infected analysis, odds ratio 1.4 (1.0-2.0); and case crossover, odds ratio 1.3 (0.5-3.1)] and 3 months [matched case- control, odds ratio 34.5 (4.1-291.3); infected analysis, odds ratio 2.3 (1.1-4.8); and case crossover, odds ratio 1.8 (0.6-5.6)] before HIV testing among acutely HIV-infected patients.We found higher odds of acute HIV infection among patients with concurrent rectal gonorrhea [17.0 (2.6-111.4), P < 0.01] or syphilis [5.8 (1.1-32.3), P = 0.04] when compared with those HIV-uninfected patients. CONCLUSIONS: Acute HIV infection was associated with a recent or concurrent STD, particularly rectal gonorrhea, among men at San Francisco's municipal STD clinic. Given the complex relationship between STDs and HIV infection, no single design will appropriately control for all the possible confounders; studies using complementary designs are required.


Subject(s)
HIV Infections/complications , Sexually Transmitted Diseases/complications , Acute Disease , Case-Control Studies , Chronic Disease , Gonorrhea/complications , Gonorrhea/epidemiology , Gonorrhea/transmission , HIV Infections/epidemiology , HIV Infections/transmission , Homosexuality, Male , Humans , Male , Retrospective Studies , San Francisco/epidemiology , Sexually Transmitted Diseases/epidemiology , Sexually Transmitted Diseases/transmission , Syphilis/complications , Syphilis/epidemiology , Syphilis/transmission
15.
Bioanalysis ; 1(6): 1057-66, 2009 Sep.
Article in English | MEDLINE | ID: mdl-21083074

ABSTRACT

Validation of LC-MS/MS assays includes an assessment of matrix effects. Hemolysis effect, a special type of matrix effect, can also have an impact on analyte quantitation. In situations where the hemolysis effect is marginal, this can be resolved simply by dilution of hemolyzed samples with plasma prior to analysis. However, in some cases, the impact can be so dramatic that analytes are completely immeasurable. In such situations, modification to the bioanalytical method will be required, including, but not limited to, adjusting the chromatographic conditions to separate interferences present in hemolyzed samples; additional sample clean-up techniques such as protein precipitation in combination with SPE or a change in extraction technique such as from SPE to a liquid-liquid extraction method. Here, we report examples from four bioanalytical methods, where the presence of hemolyzed blood in plasma was found to have an impact on analyte quantitation and a description of the solutions adopted to resolve this are provided.


Subject(s)
Blood/metabolism , Chemistry Techniques, Analytical/methods , Chromatography, Liquid/methods , Pharmaceutical Preparations/blood , Solid Phase Extraction/methods , Spectrometry, Mass, Electrospray Ionization/methods , Atorvastatin , Benzodiazepines/blood , Carbazoles/blood , Carvedilol , Hemolysis , Heptanoic Acids/blood , Microfluidics , Olanzapine , Phenylephrine/blood , Propanolamines/blood , Pyrroles/blood
16.
Hong Kong Med J ; 14(1): 50-4, 2008 Feb.
Article in English | MEDLINE | ID: mdl-18239244

ABSTRACT

The Hospital Authority Toxicology Reference Laboratory confirmed six cases of phenformin use, with or without complications, from July 2005 to November 2006. Two of the patients presented with potentially fatal phenformin-induced lactic acidosis. Phenformin was found (or suspected to be) adulterating Chinese proprietary medicine in five of the six cases. We report these six cases to highlight the underrecognised hazards posed by phenformin, a banned drug in Hong Kong.


Subject(s)
Acidosis, Lactic/chemically induced , Diabetes Mellitus/drug therapy , Drugs, Chinese Herbal/adverse effects , Hypoglycemic Agents/adverse effects , Phenformin/adverse effects , Aged , Drug Contamination , Drug Synergism , Female , Hong Kong , Humans , Male , Middle Aged , Urine/chemistry
17.
J Clin Microbiol ; 46(4): 1494-7, 2008 Apr.
Article in English | MEDLINE | ID: mdl-18234875

ABSTRACT

We have evaluated four current Food and Drug Administration-cleared rapid tests for human immunodeficiency virus (HIV)-specific antibodies with a panel of specimens from recently infected individuals. Recent infection was detected by RNA-based screening coupled with enzyme immunoassay-based testing. We found that the sensitivities of the various rapid tests vary greatly with regard to their ability to detect HIV-specific antibodies in recently infected individuals.


Subject(s)
AIDS Serodiagnosis/methods , HIV Antibodies/blood , HIV Infections/diagnosis , HIV-1/immunology , HIV-2/immunology , Reagent Kits, Diagnostic , HIV Infections/immunology , HIV Infections/virology , Humans , Immunoassay , Immunoenzyme Techniques , Reproducibility of Results , Sensitivity and Specificity , Time Factors , United States , United States Food and Drug Administration
18.
J Clin Virol ; 40(1): 68-70, 2007 Sep.
Article in English | MEDLINE | ID: mdl-17662648

ABSTRACT

BACKGROUND: Very limited data exist on the comparative performance of nucleic acid amplification tests (NATs) for the screening of pooled specimens for acute human immunodeficiency virus (HIV) infection. STUDY DESIGN: In this study, we compared a transcription-mediated-amplification assay (Procleix HIV-1 Discriminatory Assay, [TMA]) with a branched DNA assay (Bayer Versant HIV-1 RNA 3.0 assay, [bDNA]). RESULTS: After re-testing 1552 samples that were negative for HIV RNA by bDNA, we found one additional positive sample with the TMA assay. CONCLUSION: Our results suggest that TMA could potentially detect acute HIV infections missed by other technologies.


Subject(s)
HIV Infections/diagnosis , HIV-1/isolation & purification , Nucleic Acid Amplification Techniques/methods , RNA, Viral/isolation & purification , Branched DNA Signal Amplification Assay , HIV Infections/virology , HIV-1/genetics , Humans , Sensitivity and Specificity
19.
Rapid Commun Mass Spectrom ; 21(2): 169-79, 2007.
Article in English | MEDLINE | ID: mdl-17154350

ABSTRACT

Two fast and sensitive liquid chromatography/tandem mass spectrometry (LC/MS/MS)-based bioanalytical assays were developed and validated to quantify the active and three inactive metabolites of prasugrel. Prasugrel is a novel thienopyridine prodrug that is metabolized to the pharmacologically active metabolite in addition to three inactive metabolites, which directly relate to the formation and elimination of the active metabolite. After extraction and separation, the analytes were detected and quantified using a triple quadrupole mass spectrometer using positive electrospray ionization. The validated concentration range for the inactive metabolites assay was from 1 to 500 ng/mL for each of the three analytes. Additionally, a 5x dilution factor was validated. The interday accuracy ranged from -10.5% to 12.5% and the precision ranged from 2.4% to 6.6% for all three analytes. All results showed accuracy and precision within +/-20% at the lower limit of quantification and +/-15% at other levels. The validated concentration range for the active metabolite assay was from 0.5 to 250 ng/mL. Additionally, a 10x dilution factor was validated. The interbatch accuracy ranged from -7.00% to 5.98%, while the precision ranged from 0.98% to 3.39%. Derivatization of the active metabolite in blood with 2-bromo-3'-methoxyacetophenone immediately after collection was essential to ensure the stability of the metabolite during sample processing and storage. These methods have been applied to determine the concentrations of the active and inactive metabolites of prasugrel in human plasma.


Subject(s)
Chromatography, High Pressure Liquid/methods , Piperazines/blood , Platelet Aggregation Inhibitors/blood , Purinergic P2 Receptor Antagonists , Spectrometry, Mass, Electrospray Ionization/methods , Tandem Mass Spectrometry/methods , Thiophenes/blood , Drug Stability , Humans , Prasugrel Hydrochloride , Reproducibility of Results
20.
AAPS J ; 9(3): E353-60, 2007 Nov 02.
Article in English | MEDLINE | ID: mdl-18170982

ABSTRACT

The Third American Association of Pharmaceutical Scientists/Food and Drug Administration Bioanalytical Workshop, held in 2006, reviewed and evaluated current practices and proposed that carryover and contamination be assessed not only during the validation of an assay but also during the application of the method in a study. In this article, the potential risks of carryover and contamination in each stage of a bioanalytical method are discussed, to explain to the industry why this recommendation is being made.


Subject(s)
Chromatography, High Pressure Liquid/methods , Tandem Mass Spectrometry/methods , Artifacts , Automation , Reproducibility of Results
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