RESUMEN
Eosinophilic granulomatosis with polyangiitis (EGPA) is a systemic vasculitis presenting primarily with pulmonary and cutaneous features. The disease is typically seen in the fifth or sixth decade of life (1, 2). We report a case of EGPA in an adolescent who was successfully treated with the interleukin-5 (IL-5) receptor inhibitor, benralizumab.
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Síndrome de Churg-Strauss , Granulomatosis con Poliangitis , Adolescente , Humanos , Niño , Granulomatosis con Poliangitis/tratamiento farmacológico , Síndrome de Churg-Strauss/tratamiento farmacológico , Anticuerpos Monoclonales Humanizados/uso terapéuticoRESUMEN
Non-ventilated hospital-acquired pneumonia (NV-HAP) is associated with a significant healthcare burden, arising from high incidence and associated morbidity and mortality. However, accurate identification of cases remains challenging. At present, there is no gold-standard test for the diagnosis of NV-HAP, requiring instead the blending of non-specific signs and investigations. Causative organisms are only identified in a minority of cases. This has significant implications for surveillance, patient outcomes and antimicrobial stewardship. Much of the existing research in HAP has been conducted among ventilated patients. The paucity of dedicated NV-HAP research means that conclusions regarding diagnostic methods, pathology and interventions must largely be extrapolated from work in other settings. Progress is also limited by the lack of a widely agreed definition for NV-HAP. The diagnosis of NV-HAP has large scope for improvement. Consensus regarding a case definition will allow meaningful research to improve understanding of its aetiology and the heterogeneity of outcomes experienced by patients. There is potential to optimize the role of imaging and to incorporate novel techniques to identify likely causative pathogens. This would facilitate both antimicrobial stewardship and surveillance of an important healthcare-associated infection. This narrative review considers the utility of existing methods to diagnose NV-HAP, with a focus on the significance and challenge of identifying pathogens. It discusses the limitations in current techniques, and explores the potential of emergent molecular techniques to improve microbiological diagnosis and outcomes for patients.
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Neumonía Asociada a la Atención Médica , Humanos , Neumonía Asociada a la Atención Médica/diagnóstico , Neumonía Asociada a la Atención Médica/microbiología , Pruebas Diagnósticas de Rutina/métodosRESUMEN
A range of virus doses were used to infect 3-week-old chickens, turkeys and ducks intranasally/intraocularly, and infection was confirmed by the detection of virus shedding from the buccal or cloacal route by analysis of swabs collected using real-time reverse transcriptase-polymerase chain reaction assays. The median infectious dose (ID(50)) and the median lethal dose (LD(50)) values for two highly pathogenic avian influenza (HPAI) viruses of H5N1 and H7N1 subtypes and one virulent Newcastle disease virus (NDV) were determined for each virus and host combination. For both HPAI viruses, turkeys were >100-fold more susceptible to infection than chickens, while both these hosts were >10-fold more susceptible to H5N1 virus than the H7N1 virus. All infected chickens and turkeys died. Ducks were also much more readily infected with the H5N1 virus (ID(50)< or =10(1) median embryo infective dose [EID(50)]) than the H7N1 virus (ID(50)=10(4.2) EID(50)). However, the most notable difference between the two viruses was their virulence for ducks, with a LD(50) of 10(3) EID(50) for the H5N1 virus, but no deaths in ducks being attributed to infection with H7N1 virus even at the highest dose (10(6) EID(50)). For both HPAI virus infections of ducks, the ID(50) was lower than the LD(50), indicating that infected birds were able to survive and thus excrete virus over a longer period than chickens and turkeys. The NDV strain used did not appear to establish infection in ducks even at the highest dose used (10(6) EID(50)). Some turkeys challenged with 10(6) EID(50), but not other doses, of NDV excreted virus for a number of days (ID(50)=10(4.6) EID(50)), but none died. In marked contrast, chickens were shown to be extremely susceptible to infection and all infected chickens died (ID(50)/LD(50)=10(1.9) EID(50)).
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Pollos , Patos , Subtipo H5N1 del Virus de la Influenza A/patogenicidad , Gripe Aviar/fisiopatología , Enfermedad de Newcastle/fisiopatología , Virus de la Enfermedad de Newcastle/patogenicidad , Pavos , Animales , Subtipo H5N1 del Virus de la Influenza A/genética , Gripe Aviar/mortalidad , Dosificación Letal Mediana , Enfermedad de Newcastle/mortalidad , Virus de la Enfermedad de Newcastle/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Especificidad de la Especie , Virulencia , Esparcimiento de Virus/fisiologíaRESUMEN
Carbapenem-resistant Klebsiella pneumoniae (CRKP) isolates (carrying the carbapenemase gene blaNDM-5) of sequence type 16 caused hospital-acquired bloodstream infection or gut colonization in two patients in an intensive care unit (ICU). It was hypothesized that handwashing sinks were the source, and all handwashing sinks in the ICU were sampled. Whole-genome sequencing and analysis revealed that one sink was the source of CRKP colonization/infection in both patients, instead of direct transmission of a common clone between the patients. This study highlights handwashing sinks as an important source of multi-drug-resistant organisms. Sink management, including prohibition of disposal of body fluids and daily disinfection with chlorine, curbed the transmission.
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Enterobacteriaceae Resistentes a los Carbapenémicos/genética , Enterobacteriaceae Resistentes a los Carbapenémicos/aislamiento & purificación , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/aislamiento & purificación , Aguas Residuales/microbiología , Microbiología del Agua , China , Infección Hospitalaria , Bases de Datos de Ácidos Nucleicos , Desinfección de las Manos , Humanos , Unidades de Cuidados Intensivos , Infecciones por Klebsiella , Secuenciación Completa del GenomaRESUMEN
Enterococcus faecium is a gut commensal of humans and animals but is also listed on the WHO global priority list of multidrug-resistant pathogens. Many of its antibiotic resistance traits reside on plasmids and have the potential to be disseminated by horizontal gene transfer. Here, we present the first comprehensive population-wide analysis of the pan-plasmidome of a clinically important bacterium, by whole-genome sequence analysis of 1,644 isolates from hospital, commensal, and animal sources of E. faecium Long-read sequencing on a selection of isolates resulted in the completion of 305 plasmids that exhibited high levels of sequence modularity. We further investigated the entirety of all plasmids of each isolate (plasmidome) using a combination of short-read sequencing and machine-learning classifiers. Clustering of the plasmid sequences unraveled different E. faecium populations with a clear association with hospitalized patient isolates, suggesting different optimal configurations of plasmids in the hospital environment. The characterization of these populations allowed us to identify common mechanisms of plasmid stabilization such as toxin-antitoxin systems and genes exclusively present in particular plasmidome populations exemplified by copper resistance, phosphotransferase systems, or bacteriocin genes potentially involved in niche adaptation. Based on the distribution of k-mer distances between isolates, we concluded that plasmidomes rather than chromosomes are most informative for source specificity of E. faeciumIMPORTANCEEnterococcus faecium is one of the most frequent nosocomial pathogens of hospital-acquired infections. E. faecium has gained resistance against most commonly available antibiotics, most notably, against ampicillin, gentamicin, and vancomycin, which renders infections difficult to treat. Many antibiotic resistance traits, in particular, vancomycin resistance, can be encoded in autonomous and extrachromosomal elements called plasmids. These sequences can be disseminated to other isolates by horizontal gene transfer and confer novel mechanisms to source specificity. In our study, we elucidated the total plasmid content, referred to as the plasmidome, of 1,644 E. faecium isolates by using short- and long-read whole-genome technologies with the combination of a machine-learning classifier. This was fundamental to investigate the full collection of plasmid sequences present in our collection (pan-plasmidome) and to observe the potential transfer of plasmid sequences between E. faecium hosts. We observed that E. faecium isolates from hospitalized patients carried a larger number of plasmid sequences compared to that from other sources, and they elucidated different configurations of plasmidome populations in the hospital environment. We assessed the contribution of different genomic components and observed that plasmid sequences have the highest contribution to source specificity. Our study suggests that E. faecium plasmids are regulated by complex ecological constraints rather than physical interaction between hosts.
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Infección Hospitalaria/microbiología , Enterococcus faecium/genética , Enterococcus faecium/patogenicidad , Genoma Bacteriano , Plásmidos/genética , Antibacterianos/farmacología , Elementos Transponibles de ADN/genética , Enterococcus faecium/efectos de los fármacos , Transferencia de Gen Horizontal , Genómica , Infecciones por Bacterias Grampositivas/microbiología , Infecciones por Bacterias Grampositivas/transmisión , Hospitales , Humanos , Filogenia , Análisis de Secuencia de ADN , Secuenciación Completa del GenomaRESUMEN
Circulating uranium rapidly enters the brain and may cause adverse effects on the nervous system that are potentially modulated by stress. In this study, the neurological effects of a single intramuscular injection of 0, 0.1, 0.3, or 1 mg uranium/kg (as uranyl acetate, UA) in rats were examined in the presence and absence of stress. Treatment with UA produced time and dose-dependent increases in serum and regional brain uranium levels. While serum levels returned to control levels by day 30, brain levels remained elevated. Application of stress did not affect the distribution or retention of uranium. Exposure to 1 mg U/kg significantly decreased ambulatory activity, weight gain, forelimb grip strength and transiently impaired working memory. Effects on grip strength and memory were prevented by application of stress prior to uranium exposure. Striatal dopamine content was reduced by 30% 3 days after treatment with 1mg/kg (59+/-6 nmol/mg tissue versus 41+/-5 nmol/mg tissue), but levels returned to control 7 days after uranium exposure. The effect on dopamine was ameliorated by prior application of stress. Exposure to UA did not alter 3,4 dihydroxyphenylacetic acid (DOPAC) levels or numbers of D2 receptors in the striatum. No effect of uranium or stress was observed on levels of GABA, serotonin, norepinephrine, or glutathione (GSH) in the striatum, hippocampus, cerebellum, or cortex. These results indicate that single intramuscular exposures to uranium produce sustained elevation of brain uranium levels and at doses above 0.3 mg/kg can have adverse neurological effects. Application of stress prior to uranium administration modulates neurological effects, but the mechanism is not due to effects on uranium distribution. Uranium exposure also produced renal toxicity which must be considered to accurately assess the effects of uranium on neurological function.
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Conducta Animal/efectos de los fármacos , Encéfalo/efectos de los fármacos , Síndromes de Neurotoxicidad/etiología , Compuestos Organometálicos/toxicidad , Estrés Psicológico/complicaciones , Animales , Peso Corporal/efectos de los fármacos , Encéfalo/metabolismo , Encéfalo/fisiopatología , Química Encefálica/efectos de los fármacos , Corticosterona/sangre , Dopamina/metabolismo , Relación Dosis-Respuesta a Droga , Glutatión/metabolismo , Inyecciones Intramusculares , Enfermedades Renales/inducido químicamente , Locomoción/efectos de los fármacos , Masculino , Memoria/efectos de los fármacos , Fuerza Muscular/efectos de los fármacos , Síndromes de Neurotoxicidad/complicaciones , Síndromes de Neurotoxicidad/metabolismo , Síndromes de Neurotoxicidad/fisiopatología , Neurotransmisores/metabolismo , Compuestos Organometálicos/administración & dosificación , Compuestos Organometálicos/farmacocinética , Ratas , Ratas Sprague-Dawley , Estrés Psicológico/metabolismo , Estrés Psicológico/fisiopatología , Factores de Tiempo , Distribución TisularAsunto(s)
Antibacterianos/efectos adversos , Cefalosporinas/efectos adversos , Síndromes de Neurotoxicidad/etiología , Osteomielitis/tratamiento farmacológico , Infecciones por Pseudomonas/tratamiento farmacológico , Lesión Renal Aguda/inducido químicamente , Lesión Renal Aguda/complicaciones , Lesión Renal Aguda/fisiopatología , Anciano , Antibacterianos/administración & dosificación , Cefepima , Cefalosporinas/administración & dosificación , Femenino , Tasa de Filtración Glomerular , Humanos , Síndromes de Neurotoxicidad/fisiopatología , Osteomielitis/microbiología , Infecciones por Pseudomonas/microbiología , Respiración ArtificialRESUMEN
Real time reverse transcriptase (RRT)-polymerase chain reaction (PCR) for the detection of Eurasian H5 avian influenza virus (AIV) isolates was adapted from an existing protocol, optimized, and validated using a number of genetically diverse H5 isolates (n = 51). These included 34 "Asian lineage" H5N1 highly pathogenic avian influenza (HPAI) viruses (2004-2006), plus 12 other H5 isolates from poultry outbreaks and wild birds in the Eastern Hemisphere (1996-2005). All 51 were positive by H5 Eurasian RRT-PCR. Specificity was assessed by testing representative isolates from all other AL virus subtypes (n = 52), non-AI avian pathogens (n = 8), plus a negative population of clinical specimens derived from AI-uninfected wild birds and poultry (n = 604); all were negative by H5 Eurasian RRT-PCR. RNA was directly extracted from suspect HPAI H5N1 clinical specimens (Africa, Asia, and Europe; 2005-2006; n = 58) from dead poultry and wild birds, and 55 recorded as positive by H5 Eurasian RRT-PCR: Fifty-one of these 55 were in agreement with positive AIV isolation in embryonated chickens' eggs. H5 Eurasian RRT-PCR was invaluable in H5 outbreak diagnosis and management by virtue of its rapidity and high degree of sensitivity and specificity. This method provides a platform for automation that can be applied for large-scale intensive investigations, including surveillance.
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Brotes de Enfermedades/veterinaria , Subtipo H5N1 del Virus de la Influenza A/aislamiento & purificación , Gripe Aviar/epidemiología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/veterinaria , Animales , Aves/virología , Gripe Aviar/virología , Reproducibilidad de los Resultados , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Sensibilidad y Especificidad , Factores de TiempoRESUMEN
An immunochemical enzyme immunoassay model system was developed and compared for maximum sensitivity with a radioimmunoassay method and the classic enzyme activity method for the detection of pyruvate dehydrogenase complex (PDHc) and its decarboxylating subunit, pyruvate dehydrogenase (E1), isolated from Escherichia coli. Cross-linked large molecular weight antibody-enzyme conjugate systems are compared with heterobifunctional singular antibody conjugates substituted with high levels of horseradish peroxidase. Both polyclonal and monoclonal antibodies generated to the Escherichia coli PDHc and E1 antigens were used to develop a double-antibody sandwich microtiter plate enzyme-linked immunosorbent assay. It is demonstrated that a double sandwich immunochemical assay system can be quantitative for PDHc, can detect PDHc in crude cell lysates and has levels of sensitivity of 2.0.10(-16) mol for the detection of PDHc. This assay model system provides specific antibody selection criteria and coupling methods needed to select specific antisera that cross-react with human PDHc. This rapid and sensitive immunochemical assay method clearly demonstrates that sensitive mass assay systems can be developed for the detection of PDHc. Different from Western blot, this methodology could be used to generate mass assays which could be applied to the rapid detection of mammalian antigens (employing the corresponding antibodies) implicated in a number of pyruvate dehydrogenase deficiencies associated with human disorders.
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Técnicas para Inmunoenzimas , Complejo Piruvato Deshidrogenasa/análisis , Anticuerpos Monoclonales , Sitios de Unión , Ensayo de Inmunoadsorción Enzimática , Piruvato Deshidrogenasa (Lipoamida) , Complejo Piruvato Deshidrogenasa/química , Radioinmunoensayo/métodosRESUMEN
A mild and transition metal-free counteranion triggered arylation strategy has been developed using diaryliodonium fluorides. The fluoride counteranion within the hypervalent iodonium species displays unusual reactivity that activates a phenolic O-H bond leading to electrophilic O-arylation. A wide range of phenols and diaryliodonium salts are compatible with this transformation under remarkably mild conditions. Furthermore, we pre-empt the wider implications of this strategy by demonstrating the compatibility of the arylation tactic with latent carbon nucleophiles.
RESUMEN
Standard controls for quality control of cell growth (proliferation) assays in image analysis systems are not currently available. The authors have developed a system of controls, based on cultured and harvested human cell lines, that can mimic tissue sections. These controls help ensure quality control for the entire cell proliferation analysis process, from the initial cutting of the paraffin block through fixation, immunohistochemical staining, and interactive image analysis. The use of cell line controls is advantageous because of the greater cell population homogeneity and the volume of uniform slides that are obtainable, as opposed to the use of a heterogeneous tissue sample. This system provides an excellent means of evaluating the day-to-day performance of cell proliferation analysis and may also be adapted for use as a method of multi-institutional proficiency testing.
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Biomarcadores de Tumor/análisis , División Celular/fisiología , Citometría de Imagen/normas , Técnicas para Inmunoenzimas/normas , Antígeno Ki-67/análisis , Biomarcadores de Tumor/inmunología , Línea Celular , Humanos , Citometría de Imagen/métodos , Antígeno Ki-67/inmunología , Control de CalidadRESUMEN
Currently, there are no standard controls available for quality control of DNA ploidy assays in image analysis systems. The authors have developed a system of controls based on cultured human cell lines that can mimic tissue sections and touch preparations. This allows for quality control for the entire process for DNA ploidy analysis from the initial cutting of the paraffin block or production of the touch preparation through fixation, staining, and interactive image analysis. The use of cell line controls rather than normal tissue is advantageous because of cell population homogeneity and the volume of uniform slides that are obtainable. This system, while providing an excellent means of controlling day-to-day performance of DNA ploidy analysis, may also be adapted for use as a means of multi-institutional proficiency testing.
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Técnicas Citológicas/normas , ADN/genética , Técnicas Histológicas/normas , Procesamiento de Imagen Asistido por Computador/normas , Ploidias , ADN de Neoplasias/genética , Células HeLa , Humanos , Control de CalidadRESUMEN
This study investigated whether repetition improves older adults' memory for health service appointment messages delivered by automated telephone systems. Whereas imposed repetition reduces age differences in memory (Morrow, Leirer, Carver, Tanke, & McNally, 1999), the present study examined the effect of optional repetition. Both older and younger participants in Experiment 1 chose to repeat messages. More repetition, higher cognitive ability (working memory and processing speed), and younger age were associated with better memory for appointment information. The effect of age was eliminated when cognitive ability, but not repetition, was controlled. Thus, older adults used optional repetition in automated systems, but this strategy did not eliminate age differences in memory. In Experiment 2, older as well as younger adults took accurate notes and also repeated messages. Both note-taking and message repetition improved memory for the messages but did not reduce age differences. These findings suggest that older as well as younger adults use presentation strategies in automated messaging systems. Older adults may not take full advantage of these strategies, perhaps because of age-related declines in self-initiated or metacognitive processes.
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Envejecimiento/fisiología , Actitud Frente a la Salud , Comunicación , Memoria/fisiología , Adulto , Factores de Edad , Anciano , Citas y Horarios , Cognición/fisiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Periodicidad , Encuestas y CuestionariosRESUMEN
While expectancies are considered to be an important cognitive variable in the etiology and maintenance of substance use, less is known about their role in attitudes toward addictive behavior change. It has recently been suggested that negative alcohol expectancies, in particular, might play a fundamental role in motivation to change. Among a population of college student binge drinkers, the differential ability of positive and negative expectancies to predict total readiness to change (RTC) scores was examined. Hierarchical regression analyses revealed that controlling for level of consumption and number of drinking-related problems, negative and not positive expectancies significantly predicted RTC. In an examination of expectancy subtypes, negative emotional expectancies emerged as the only significant predictor of change motivation. Possible explanations for the findings and implications for interventions with undergraduate heavy drinkers are discussed.
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Consumo de Bebidas Alcohólicas/psicología , Emociones , Disposición en Psicología , Adolescente , Adulto , Trastornos Relacionados con Alcohol/psicología , Análisis de Varianza , Actitud , Toma de Decisiones , Femenino , Humanos , Masculino , Asunción de Riesgos , EstudiantesRESUMEN
A controlled study was undertaken to determine the stability of LSD in pooled urine samples. The concentrations of LSD in urine samples were followed over time at various temperatures, in different types of storage containers, at various exposures to different wavelengths of light, and at varying pH values. LSD concentrations were measured quantitatively by the Abuscreen RIA and by HPLC using a fluorescence detection method. Good correlation was observed between the immunoassay and the fluorescent integrity of the LSD molecule. Thermostability studies were conducted in the dark with various containers. These studies demonstrated no significant loss in LSD concentration at 25 degrees C for up to 4 weeks. After 4 weeks of incubation, a 30% loss in LSD concentration at 37 degrees C and up to a 40% at 45 degrees C were observed. Urine fortified with LSD and stored in amber glass or nontransparent polyethylene containers showed no change in concentration under any light conditions. Stability of LSD in transparent containers under light was dependent on the distance between the light source and the samples, the wavelength of light, exposure time, and the intensity of light. After prolonged exposure to heat in alkaline pH conditions, 10 to 15% of the parent LSD epimerized to iso-LSD. Under acidic conditions, less than 5% of the LSD was converted to iso-LSD. We also demonstrated that trace amounts of metal ions in buffer or urine could catalyze the decomposition of LSD and that this process can be avoided by the addition of EDTA. This study demonstrates the importance of proper storage conditions of LSD in urine in order to insure proper analytical testing results over time.
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Alucinógenos/orina , Dietilamida del Ácido Lisérgico/orina , Detección de Abuso de Sustancias/métodos , Cloruros , Cromatografía Líquida de Alta Presión , Estabilidad de Medicamentos , Almacenaje de Medicamentos/métodos , Compuestos Férricos/química , Fluorescencia , Calor , Humanos , Concentración de Iones de Hidrógeno , Luz , Radioinmunoensayo , Rayos UltravioletaRESUMEN
A study was conducted to determine the conditions needed to achieve the equilibrium concentration for the epimerization of d-lysergic acid diethylamide (LSD) to iso-LSD. The reaction was followed by integration of the C-9 resonance of LSD and iso-LSD by proton nuclear magnetic resonance (NMR). The C-9 resonance of LSD and iso-LSD appear as singlets at 6.35 and 6.27 ppm respectively. Starting with pure LSD, the conversion to iso-LSD is attained at temperatures above 37 degrees C and pH levels over 7.0. At a pH of 7.0 or higher, the LSD/iso-LSD ratio of 9:1 is achieved after one week at 45 degrees C or two weeks at 37 degrees C. Starting with iso-LSD, the conversion to LSD requires more vigorous conditions. The 9:1 LSD/iso-LSD ratio is attained only after 6 weeks at a temperature of 45 degrees C and a pH of 9.7. At lower pH levels, the reaction proceeds more slowly. The 9:1 LSD/iso-LSD ratio is achieved whether the starting material is LSD or iso-LSD and therefore represents an equilibrium concentration (K = 9). In addition, the more vigorous conditions needed to achieve equilibrium of iso-LSD to LSD demonstrate the difficulty in extraction of the epimerizable proton of iso-LSD. This study is the first to quantitate the epimerization of LSD by NMR techniques and establishes the conditions needed to induce epimerization in solution.
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Dietilamida del Ácido Lisérgico/química , Estabilidad de Medicamentos , Concentración de Iones de Hidrógeno , Espectroscopía de Resonancia Magnética , Solventes , Estereoisomerismo , Factores de TiempoRESUMEN
A homogenous microparticle-based immunoassay has been developed for the detection of d-lysergic acid diethylamide (LSD) in human urine using the Online technology. This immunoassay is based on the principle of the kinetic interaction of microparticles in a solution where the drug content of the urine is directly proportional to the inhibition of the microparticle aggregation. Antibodies to LSD were obtained by immunizing goats with an LSD analogue derivatized through the indole nitrogen and conjugated to bovine thyroglobulin. The assay cutoff is 0.5 ng/mL LSD, and the clinical sensitivity for the detection of LSD and its metabolites in human urine samples is equivalent to the LSD Abuscreen RIA. Thirty-one samples previously screened LSD positive by Abuscreen RIA and confirmed by gas chromatography-mass spectrometry were analyzed by the Abuscreen OnLine LSD and Abuscreen LSD RIA assays. All thirty-one samples screened positive in the Abuscreen OnLine and Abuscreen RIA. OnLine's cross-reactivity to nor-LSD is greater than thirty-five percent; other structurally related compounds have similar cross-reactivity to that of the Abuscreen RIA. One thousand presumed negative urine samples were also analyzed; 992 (99.2%) of these gave negative results. The eight OnLine positive samples from this set were found to be negative by Abuscreen RIA. Typical qualitative within-run precision on the Hitachi 717 (at x = cutoff of 0.5 ng/mL; 0.5x, 1.0x, and 1.5x) was found to be less than 2.5%. Between-run precision was less than 3.0%.
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Dietilamida del Ácido Lisérgico/orina , Animales , Formación de Anticuerpos , Especificidad de Anticuerpos , Bovinos , Reacciones Cruzadas , Relación Dosis-Respuesta a Droga , Cromatografía de Gases y Espectrometría de Masas , Humanos , Indoles/química , Sistemas en Línea , Tamaño de la Partícula , Radioinmunoensayo , Estándares de Referencia , Tiroglobulina/metabolismoRESUMEN
A clinical study was conducted to assess the ability of commercially available immunoassays to detect flunitrazepam (FNP) in plasma and urine samples and to compare the results with those obtained by gas chromatography-mass spectrometry (GC-MS). The clinical study consisted of four individuals (two male and two female) who had taken a single 2-mg dose of FNP. Serum was collected over a 48-h period and urine was collected over a 72-h period. The serum and urine samples were analyzed by the COBAS INTEGRA Serum Benzodiazepines assay (SBENZ), the TDx serum and urine Benzodiazepines assay, and GC-MS. The GC-MS procedure was developed for analysis of FNP and metabolites in plasma and urine using an acid hydrolysis step resulting in the formation of specific benzophenones corresponding to FNP and its metabolites. The relative sensitivities of the assays for the detection of FNP and metabolites in serum and urine were GC-MS > SBENZ > TDx. The immunoassay results for serum samples showed peak concentrations of FNP metabolites at 8 h after FNP ingestion for three individuals and at about 1 h for the fourth individual. The GC-MS, SBENZ, and TDx urine immunoassays detected drug above the stated limit of detection (LOD) in 44, 41, and 35 serial FNP urine samples, respectively. FNP metabolites were detected in urine samples with all three assays for up to 72 h after a 2-mg dose. The improved detection rate with the SBENZ assay as compared to the TDx assay is likely explained by its higher cross-reactivity with the major metabolite, 7-amino-flunitrazepam (7-amino-FNP), and its lower LOD.
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Ansiolíticos/sangre , Ansiolíticos/orina , Flunitrazepam/análogos & derivados , Flunitrazepam/sangre , Flunitrazepam/orina , Inmunoensayo/normas , Administración Oral , Adulto , Ansiolíticos/metabolismo , Femenino , Flunitrazepam/metabolismo , Cromatografía de Gases y Espectrometría de Masas , Humanos , Masculino , Sensibilidad y Especificidad , Detección de Abuso de SustanciasRESUMEN
A study was conducted to compare the clinical sensitivity of the OnLine and EMIT II assays for propoxyphene (PPX) use in human urine. A total of 5138 random clinical samples were evaluated by both OnLine and EMIT II. Samples that were positive for each immunoassay were confirmed for PPX and norpropoxyphene (NPPX) by gas chromatography-mass spectrometry (GC-MS). There were 14 samples that were identified positive by both immunoassays and confirmed positive by GC-MS. An additional six samples were positive by OnLine, negative by EMIT II, and confirmed positive by GC-MS. There was one unconfirmed positive sample identified by each immunoassay, and 5116 samples were identified as negative by both immunoassays. The increased sensitivity by OnLine can be attributed to the cross reactivity of the OnLine antibody, which is higher than the cross reactivity of the EMIT II antibody for NPPX (77% versus 7%, respectively). The high concentrations of NPPX, relative to those of PPX, found in all of the clinical samples suggest that laboratories that currently confirm for PPX should confirm for NPPX in order to obtain a better correlation between immunoassay results and GC-MS confirmations.
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Analgésicos Opioides/análisis , Dextropropoxifeno/análogos & derivados , Dextropropoxifeno/análisis , Cromatografía de Gases y Espectrometría de Masas/métodos , Inmunoensayo/métodos , Juego de Reactivos para Diagnóstico , Dextropropoxifeno/inmunología , Humanos , Sensibilidad y Especificidad , Detección de Abuso de Sustancias/métodosRESUMEN
A study was conducted to compare the performance of the OnLine and OnTrak immunoassays for benzodiazepines with gas chromatographic-mass spectrometric (GC-MS) analysis in detecting flunitrazepam (FNP) and its metabolites in human urine. Urine was collected over a 72-h period from six individuals (four male and two female) who had taken a single oral dose of either 1 or 4 mg of FNP. The OnTrak assay was run at a 100-ng/mL cutoff of nordiazepam (NDP), and the OnLine assay was run with a standard curve from zero to 200 ng/mL of NDP with and without beta-glucuronidase treatment. Each sample was analyzed by GC-MS using FNP, 7-amino-FNP, 3-hydroxy-FNP, desmethyl-FNP, 7-amino-3-hydroxy-FNP, and desmethyl-3-hydroxy-FNP as standards with beta-glucuronidase treatment. The specimens from the 1-mg dose did not yield a positive result by immunoassay over the 72-h collection period. Specimens from the 4-mg dose did yield positive results in both immunoassays. The time of the first positive result ranged from 4 to 12 h, and the time to the last positive result ranged from 18 to 60 h. Treatment of the samples with beta-glucuronidase increased the OnLine values between 20 and 60%, but it did not appreciably increase the detection time. GC-MS analysis showed no detectable levels of FNP, 3-hydroxy-FNP, desmethyl-FNP, 7-amino-3-hydroxy-FNP, and desmethyl-3-hydroxy-FNP. However, all samples collected past time zero showed detectable levels of 7-amino-FNP (> 2 ng/mL) with peak concentrations at 12-36 h. The peak levels of 7-amino-FNP by GC-MS paralleled the peak levels of the immunoassay response. The amount of 7-amino-FNP metabolite quantitated by GC-MS, however, accounted for only 15-20% of the total immunoassay crossreactive FNP metabolites.