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1.
J Chromatogr Sci ; 47(1): 57-66, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19161658

RESUMEN

Membrane introduction mass spectrometry (MIMS) is emerging as an important technique for on-line, real-time environmental monitoring. Because MIMS interfaces are simple and robust, they are ideally suited for operation in MS instrumentation used for in-field applications. We report the use of an on-line permeation tube to continuously infuse an isotopically labeled internal standard for continuous quantitative determinations in atmospheric and aqueous samples without the need for off-line calibration. This approach also provides important information on the operational performance of the analytical system during multi-day deployments. We report measured signal stability during on-line deployments in air and water of 7% based on variation of the internal standard response and have used this technique to quantify BTEX (benzene, toluene, ethylbenzenes, and xylenes), pinenes, naphthalene and 2-methoxyphenol (guaiacol) in urban air plumes at parts-per-billion by volume levels. Presented are several recent applications of MIMS-MS-MS for on-line environmental monitoring in atmospheric and aqueous environmental samples demonstrating laboratory, remote and mobile deployments. We also present the use of a thermally assisted MIMS interface for the direct measurement of polyaromatic hydrocarbons, alkylphenols, and other SVOCs in the low ppb range in aqueous environmental samples and discuss improvements in both the sensitivity and response times for selected SVOCs. The work presented in this paper represents significant improvements in field deployable mass spectrometric techniques, which can be applied to direct on-site analytical measurements of VOC and SVOCs in environmental samples.


Asunto(s)
Contaminantes Atmosféricos/análisis , Espectrometría de Masas/instrumentación , Espectrometría de Masas/métodos , Contaminantes Químicos del Agua/análisis , Membranas Artificiales , Hidrocarburos Policíclicos Aromáticos/análisis , Estándares de Referencia , Sensibilidad y Especificidad , Temperatura , Factores de Tiempo , Volatilización
2.
Br Dent J ; 232(7): 423, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35396399
3.
Br Dent J ; 229(4): 209, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32855448
4.
J Am Diet Assoc ; 80(6): 557-60, 1982 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7086008

RESUMEN

The acceptability of ground venison was evaluated by 91 consumers. Four meat patties were formulated: 100 percent beef, 100 venison, 50 percent venison/50 percent beef, and 50 percent venison/50 percent pork. The four patties received similar acceptability scores, except that the all-venison patty was less juicy and had a stronger game flavor. Mixing venison with beef or pork in a patty with about 18 percent fat increased the juiciness and decreased the game flavor. Mixing ground venison with ground beef or pork could make venison more palatable to consumers.


Asunto(s)
Carne/normas , Animales , Bovinos , Culinaria , Ciervos , Preferencias Alimentarias , Humanos , Carne/análisis , Porcinos
5.
Can J Gastroenterol ; 11(3): 217-9, 1997 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9167028

RESUMEN

Inflammatory bowel disease is rarely associated with pericarditis but both sulfasalazine and the aminosalicylates have been known to cause this complication. To the author's knowledge this is the first reported case of acute pericarditis caused by azathioprine. It is believed that pericarditis is yet another potential manifestation of hypersensitivity to this drug.


Asunto(s)
Antimetabolitos/efectos adversos , Azatioprina/efectos adversos , Colitis Ulcerosa/tratamiento farmacológico , Pericarditis/inducido químicamente , Adulto , Antimetabolitos/uso terapéutico , Azatioprina/uso terapéutico , Colitis Ulcerosa/diagnóstico , Colitis Ulcerosa/fisiopatología , Diagnóstico Diferencial , Ecocardiografía , Electrocardiografía , Humanos , Masculino , Pericarditis/diagnóstico , Pericarditis/fisiopatología
6.
Psychiatr Serv ; 52(1): 81-6, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11141533

RESUMEN

OBJECTIVE: Data from electroencephalograms (EEGs), including data from visual evoked-potential studies, were analyzed to assess their association with a specific type of explosive behavior in children and adolescents. METHODS: Data for 326 children and adolescents treated in a psychiatric clinic were examined. Eighty-two percent exhibited behavior consistent with intermittent explosive disorder, although diagnosis was not an inclusion criterion for the study. The presence of explosive behaviors was indicated by reports from the legal system, schools, parents, health care workers, and psychiatric intake interviews. A quantitative EEG and a series of pattern-reversal evoked-potential studies were administered to each patient. In these studies, children are shown a rapidly reversing checkerboard pattern or rapid flashes of light, and their brain waves (evoked potentials) are measured. RESULTS: Logistic regression indicated that patients who exhibited explosive behaviors were significantly more likely to produce high-amplitude P100 wave forms in the evoked-potential studies than patients who did not exhibit explosive behaviors. Forty-six percent of those with explosive behaviors met the clinically defined electrophysiological criteria for the high-amplitude P100 wave forms. CONCLUSIONS: The use of visual evoked-potential studies helped us classify a large subset of youths who exhibited out-of-control explosive behaviors. The findings suggest that a subgroup of individuals exhibiting explosive behaviors may have a predisposition for violent or explosive behavior that is an innate characteristic of their central nervous system. An understanding of the etiology of explosive behaviors permits the use of more appropriate intervention and treatment strategies.


Asunto(s)
Agresión , Encéfalo/fisiopatología , Trastornos Disruptivos, del Control de Impulso y de la Conducta/fisiopatología , Electroencefalografía , Potenciales Evocados Visuales , Conducta Impulsiva/fisiopatología , Temperamento , Adolescente , Niño , Trastornos Disruptivos, del Control de Impulso y de la Conducta/clasificación , Trastornos Disruptivos, del Control de Impulso y de la Conducta/diagnóstico , Femenino , Predisposición Genética a la Enfermedad , Humanos , Sistema Límbico/fisiopatología , Modelos Logísticos , Masculino , Estudios Retrospectivos
7.
Sci Total Environ ; 181(3): 265-78, 1996 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-8820441

RESUMEN

Surficial marine sediments from 20 sites within the Kitimat fjord system were analyzed for polycylic aromatic hydrocarbons (PAHs). Levels of the sum of the 16 USEPA priority pollutant PAHs varied from below detection limits (ca. 1 microg x g-1) to over 10 000 microg x g-1. Sediment PAH levels were highest in the immediate vicinity of a large aluminum smelter at the head of Kitimat Arm, and declined rapidly with increasing distance from the smelter. However, even at some of the more distant sites which are geographically isolated from the smelter PAH levels were elevated. The PAH distribution in the fjord system is consistent with a combination of aeolian and fluvial transport of PAHs emitted by the aluminum smelter at the head of Kitimat Arm. The mixture of PAHs present was qualitatively similar in all samples analyzed, including those from the distant sites. All aspects of the PAH composition are consistent with combustion generated PAHs. A correlation between PAH levels and sediment organic carbon was observed; however, this was only significant for highly contaminated sites in the harbor. This probably reflects the high organic content of particulate emissions from the smelter, rather than equilibrium partitioning of PAHs to sediment organic carbon within the harbor itself.


Asunto(s)
Aluminio , Sedimentos Geológicos/química , Compuestos Policíclicos/análisis , Contaminantes Químicos del Agua/análisis , Colombia Británica , Carbono/análisis
8.
J Wildl Dis ; 15(3): 443-6, 1979 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-228088

RESUMEN

Sera were collected from 12 Barbary sheet (Ammotragus lervia) and 11 mule deer (Odocoileus hemionus) occupying sympatric ranges in Palo Duro Canyon, Texas. These were tested for leptospirosis, brucellosis, bovine virus diarrhea, anaplasmosis, vesicular stomatitis, bluetongue (BT), epizootic hemorrhagic disease (EHD), infectious bovine rhinotracheitis (IBR), and coccidioidomycosis. Serologic reactors were found to IBR in 3 Barbery sheep, BT in 6 Barbary sheep and 6 mule deer and EHD in 3 Barbary sheep and 4 mule deer. Possible ramifications of evidence for these diseases in wild herbivore populations in this area are discussed.


Asunto(s)
Anticuerpos/análisis , Ciervos/inmunología , Ovinos/inmunología , Anaplasmosis/epidemiología , Anaplasmosis/inmunología , Animales , Lengua Azul/epidemiología , Lengua Azul/inmunología , Diarrea Mucosa Bovina Viral/epidemiología , Diarrea Mucosa Bovina Viral/inmunología , Brucelosis/epidemiología , Brucelosis/inmunología , Brucelosis/veterinaria , Bovinos , Coccidioidomicosis/epidemiología , Coccidioidomicosis/inmunología , Coccidioidomicosis/veterinaria , Rinotraqueítis Infecciosa Bovina/epidemiología , Rinotraqueítis Infecciosa Bovina/inmunología , Leptospirosis/epidemiología , Leptospirosis/inmunología , Leptospirosis/veterinaria , Texas , Virus de la Estomatitis Vesicular Indiana/inmunología
9.
Br Dent J ; 227(3): 176, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31399652

Asunto(s)
Decepción
12.
14.
J Expo Sci Environ Epidemiol ; 19(4): 349-58, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-18446186

RESUMEN

Urinary methoxyphenols (MPs) have been proposed as biomarkers of woodsmoke exposure. However, few field studies have been undertaken to evaluate the relationship between woodsmoke exposure and urinary MP concentrations. We conducted a pilot study at the US Forest Service-Savannah River Site, in which carbon monoxide (CO), levoglucosan (LG), and particulate matter (PM(2.5)) exposures were measured in wildland firefighters on prescribed burn days. Pre- and post-shift urine samples were collected from each subject, and cross-shift changes in creatinine-corrected urinary MP concentrations were calculated. Correlations between exposure measures and creatine-adjusted urinary MP concentrations were explored, and regression models were developed relating changes in urinary MP concentrations to measured exposure levels. Full-shift measurements were made on 13 firefighters over 20 work shifts in winter 2004 at the US Forest Service Savannah River site, a National Environmental Research Park. The average workshift length across the 20 measured shifts was 701+/-95 min. LG and CO exposures were significantly correlated for samples where the filter measurement captured at least 60% of the work shift (16 samples), as well as for the smaller set of full-shift exposure samples (n=9). PM(2.5) and CO exposures were not significantly correlated, and LG and PM(2.5) exposures were only significantly correlated for samples representing at least 60% of the work shift. Creatinine-corrected urinary concentrations for 20 of the 22 MPs showed cross-shift increases, with 14 of these changes showing statistical significance. Individual and summed creatinine-adjusted guaiacol urinary MPs were highly associated with CO (and, to a lesser degree, LG) exposure levels, and random-effects regression models including CO and LG exposure levels explained up to 80% of the variance in cross-shift changes in summed creatinine-adjusted guaiacol urinary MP concentrations. Although limited by the small sample size, this pilot study demonstrates that urinary MP concentrations may be effective biomarkers of occupational exposure to wood smoke among wildland firefighters.


Asunto(s)
Monóxido de Carbono/toxicidad , Monitoreo del Ambiente , Incendios , Glucosa/análogos & derivados , Exposición Profesional , Fenoles/orina , Humo , Adulto , Creatinina/orina , Glucosa/toxicidad , Humanos , Tamaño de la Partícula , Proyectos Piloto , Estados Unidos
15.
Chem Res Toxicol ; 13(4): 271-80, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10775327

RESUMEN

r-7,t-8,9,c-10-Tetrahydroxy-7,8,9,10-tetrahydrobenzo[a]pyrene (trans-anti-BaP-tetraol) is the major hydrolysis product of r-7, t-8-dihydroxy-t-9,10-epoxy-7,8,9,10-tetrahydrobenzo[a]pyrene (anti-BPDE), the principal ultimate carcinogen of the environmental pollutant benzo[a]pyrene (BaP). As part of a program to establish activation/detoxification profiles of urinary metabolites of BaP in humans, we developed a method for quantifying trans-anti-BaP-tetraol. Urine was collected from three groups of individuals exposed to BaP: psoriasis patients treated with a coal tar-containing ointment, steel workers, and smokers. [(2)H(12)]-trans-anti-BaP-tetraol was added to the urine as an internal standard. The urine was treated with beta-glucuronidase and sulfatase, and then the BaP-tetraols were enriched by reverse-phase and phenylboronic acid solid-phase extraction. The resulting fraction was treated with sodium hydride and methylmethane sulfonate to convert BaP-tetraols to the corresponding tetramethyl ethers (BaP-TME). The mixture was purified by normal-phase HPLC and analyzed by gas chromatography/negative ion chemical ionization/mass spectrometry with selected ion monitoring. [(13)CH(3)](4)-trans-anti-BaP-TME was used as an external standard. Ions at m/z 376, 380, and 388 were monitored for quantitation of trans-anti-BaP-TME, [(13)CH(3)](4)-trans-anti-BaP-TME, and [(2)H(12)]-trans-anti-BaP-TME, respectively. The instrumental detection limit was approximately 1 fmol of trans-anti-BaP-TME. trans-anti-BaP-tetraol (as trans-anti-BaP-TME) was detected in 20 of 20 individuals receiving coal tar therapy (mean, 16 fmol/mL of urine), 13 of 13 exposed steel workers (mean, 4.1 fmol/mL of urine), and nine of 21 cigarette smokers (mean, 0.5 fmol/mL of urine). The means in these groups were significantly different (P < 0.0001). The urine of steel workers was also analyzed for cis-anti-BaP-tetraol and cys-syn-BaP-tetraol, but neither was found. The results of this study provide a quantitative method for determination of parts per trillion levels of trans-anti-BaP-tetraol in human urine. Ultimately, this method can be employed as part of a phenotyping approach for assessing BaP metabolites in human urine.


Asunto(s)
7,8-Dihidro-7,8-dihidroxibenzo(a)pireno 9,10-óxido/metabolismo , Benzo(a)pireno/metabolismo , Carcinógenos/metabolismo , Cromatografía de Gases y Espectrometría de Masas , Humanos
16.
J Clin Microbiol ; 36(11): 3198-204, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9774565

RESUMEN

We report the characterization of a type-common human recombinant monoclonal antibody previously isolated by antigen selection from a phage-displayed combinatorial antibody library established from a herpes simplex virus (HSV)-seropositive individual. Competition with well-characterized murine monoclonal antibodies and immunodetection of gD truncations revealed that this antibody recognizes the group Ib antigenic site of glycoprotein D, a highly conserved and protective type-common determinant. To our knowledge, this is the first human group Ib monoclonal antibody ever described. The antibody also displayed first-order neutralization kinetics and a high neutralization rate constant, was capable of completely inhibiting syncytium formation by a fusogenic strain of HSV type 1, and efficiently neutralized low-passage clinical isolates of both HSV serotypes. Taken together with our earlier observations of the in vivo antiviral activities of this human recombinant antibody in animal models of HSV infection, the present results support the high therapeutic potential of this antibody.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Anticuerpos Antivirales/uso terapéutico , Simplexvirus/inmunología , Animales , Anticuerpos Monoclonales/clasificación , Anticuerpos Monoclonales/genética , Anticuerpos Antivirales/genética , Anticuerpos Antivirales/metabolismo , Antígenos Virales/genética , Chlorocebus aethiops , Efecto Citopatogénico Viral/inmunología , Mapeo Epitopo , Herpes Simple/terapia , Herpesvirus Humano 1/genética , Herpesvirus Humano 1/inmunología , Herpesvirus Humano 2/genética , Herpesvirus Humano 2/inmunología , Humanos , Inmunización Pasiva , Técnicas In Vitro , Cinética , Ratones , Pruebas de Neutralización , Proteínas Recombinantes/genética , Proteínas Recombinantes/inmunología , Proteínas Recombinantes/uso terapéutico , Células Vero , Proteínas del Envoltorio Viral/genética , Proteínas del Envoltorio Viral/inmunología
19.
Environ Sci Technol ; 31(8): 343A, 1997 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21650404
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