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1.
Appl Opt ; 58(22): 6152-6156, 2019 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-31503940

RESUMEN

Refractometry is important for characterizing the optical performance of materials. The refractive index can quickly be assessed using critical angle or thin-film techniques. However, these methods only assess the material surface. Measurement of bulk refractive index is performed by measuring the refracted angle of a transmitted beam but requires precision sample geometry. The method presented here avoids costly sample preparation by measuring the sample geometry and refracted angle simultaneously, using reflections from the front and back surfaces of a wedge of material. The method is demonstrated for polydimethylsiloxane prepared under a range of curing conditions, and no significant dependence was observed. Spectral dependence is characterized, and Sellmeier coefficients are reported.

2.
Plant Dis ; 100(1): 32-39, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30688574

RESUMEN

During surveys for postharvest diseases of apple and pear, an unknown postharvest fruit rot was observed in Washington State. The disease appeared to originate from infection of the stem and calyx tissue of the fruit or wounds on the fruit. An unknown pycnidial fungus was consistently isolated from the decayed fruit. Isolates from apple and pear were characterized and identified by molecular phylogenetic analysis and morphology. Pathogenicity of representative isolates on apple and pear fruit was tested under laboratory or field conditions. A BLAST search in GenBank showed that isolates differed from Phacidium lacerum and its synonym, Ceuthospora pinastri, by only 0 to 4 bp in sequences within part of the combined large ribosomal subunit + internal transcribed spacer + small ribosomal subunit regions. The phylogenetic analysis confirmed the taxonomic placement of the unknown fungus in the genus Phacidium, with the highest match being C. pinastri (formerly anamorphic P. lacerum) and with closely related taxa from GenBank forming congeneric clades. The fungus grew at 0 to 30°C and formed unilocular to multilocular pycnidial conidiomata on artificial media after approximately 5 to 7 days at room temperature. On potato dextrose agar incubated for a 12-h photoperiod, semi-immersed globose to subglobose pycnidial conidiomata were 250 to 1,000 µm in diameter (mean = 350), with 1 to 3 nonpapillate to slightly papillate ostioles and a buff conidial matrix. Conidia produced on phialides were 8 to 13 by 1.5 to 2.5 µm, hyaline, aseptate, cylindrical, with an abruptly tapered, typically slightly protuberant base, 2 to 3 guttules, and sometimes with a mucilaginous, flexuous, unbranched appendage which is attached to the apex of the conidium and disappears with age. Conidiogenous cells were flask shaped and 6 to 15 ×1.5 to 3 µm. Colony characteristics included felt-like aerial white mycelium, gray olivaceous at the center becoming greenish to colorless toward the margin, in concentric rings, with pycnidia forming in 5 to 7 days originating from the center of the plate. Morphological characteristics of the fungus had the greatest conformity with the description for C. pinastri. Based on molecular and morphological data, the fungus is identified as P. lacerum. 'Fuji' apple fruit and 'd'Anjou' pear fruit that were wounded, inoculated with representative isolates, and incubated at 0°C yielded the same symptoms as seen on decayed fruit collected from commercial fruit packinghouses. Stem-end rot, calyx-end rot, and wound-associated rot developed on fruit inoculated in the orchard after 3 months of cold storage. The fungus was reisolated from the diseased fruit. This is the first report of a fruit rot in apple and pear caused by P. lacerum. We propose Phacidium rot as the name of this disease.

3.
Persoonia ; 32: 52-82, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25264383

RESUMEN

The genus Lopadostoma (Xylariaceae, Xylariales) is revised. Most species formerly assigned to Lopadostoma do not belong to the genus. Twelve species are herein recognised, of which two are only known from morphology. Ten species, of which six (L. americanum, L. fagi, L. insulare, L. lechatii, L. meridionale and L. quercicola) are newly described, are characterised by both morphology and DNA phylogeny using LSU, ITS and rpb2 sequences. Morphologically, ecologically and phylogenetically Lopadostoma is a well-defined genus comprising exclusively species with pustular pseudostroma development in bark of angiospermous trees. Phaeosperma ailanthi, Phaeosperma dryophilum and Sphaeria linosperma are combined in Lopadostoma. Lopadostoma gastrinum is neotypified and L. turgidum is lecto- and epitypified. Species with asci and ascospores similar to those of Lopadostoma but having perithecia immersed in wood, particularly those of Lopadostoma subg. Anthostomopsis have been determined to be unrelated to the genus. DNA data confirm that Anthostoma is unrelated to Lopadostoma. Its type and currently only confirmed species Anthostoma decipiens belongs to Diatrypaceae. DNA data also show that L. pouzarii and Barrmaelia macrospora are unrelated to Lopadostoma. A commentary is provided for names in Lopadostoma and those names in Anthostoma that may be putative species of Lopadostoma based on their protologues. Anthostoma insidiosum is an older name for Anthostomella (Diatrype) adusta.

4.
Phys Rev Lett ; 111(3): 033903, 2013 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-23909326

RESUMEN

Despite major importance in physics, biology, and other sciences, the optical sensing of nanoscale structures in the far zone remains an open problem due to the fundamental diffraction limit of resolution. We establish that the expected value of spectral variance (Σ[over ˜](2)) of a far-field, diffraction-limited microscope image can quantify the refractive-index fluctuations of a label-free, weakly scattering sample at subdiffraction length scales. We report the general expression of Σ[over ˜] for an arbitrary refractive-index distribution. For an exponential refractive-index spatial correlation, we obtain a closed-form solution of Σ[over ˜] that is in excellent agreement with three-dimensional finite-difference time-domain solutions of Maxwell's equations. Sensing complex inhomogeneous media at the nanoscale can benefit fields from material science to medical diagnostics.


Asunto(s)
Interferometría/métodos , Modelos Teóricos , Nanotecnología/métodos , Refractometría/métodos , Luz , Dispersión de Radiación
5.
Opt Lett ; 37(10): 1601-3, 2012 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-22627509

RESUMEN

Various staining techniques are commonly used in biomedical research to investigate cellular morphology. By inducing absorption of light, staining dyes change the intracellular refractive index due to the Kramers-Kronig relationship. We present a method for creating 2D maps of real and imaginary refractive indices of stained biological cells using their thickness and absorptance. We validate our technique on dyed polystyrene microspheres and quantify the alteration in refractive index of stained biological cells. We reveal that specific staining of individual organelles can increase their scattering cross-section by orders of magnitudes, implying a major impact in the field of biophotonics.


Asunto(s)
Células Epiteliales/citología , Células Epiteliales/metabolismo , Fenómenos Ópticos , Coloración y Etiquetado , Eosina Amarillenta-(YS)/metabolismo , Hematoxilina/metabolismo , Espacio Intracelular/metabolismo
6.
Matern Child Health J ; 14(3): 360-4, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-19353254

RESUMEN

OBJECTIVE: To match Michigan birth and newborn screening records to identify and follow-up potentially unscreened infants, assess data quality, and demonstrate the utility of Link Plus linkage software for matching MCH related administrative datasets. METHODS: Birth and newborn screening records maintained by the Michigan Department of Community Health from January 2007 through March 2008 were used in this study. Link Plus, a freely-available probabilistic record linkage software program developed at the Centers for Disease Control and Prevention, was used to match records. Linkage performance was assessed by the linkage success rate (percentage of valid matches). Follow-up of un-matched records was conducted by the Michigan Newborn Screening Follow-up Program. RESULTS: Nearly all (99.2%) of the 142,178 birth records included in this study were successfully matched to newborn screening records. Following a transition to a web-based electronic birth certificate system and inclusion of a newborn screening card identification number on the birth record in 2008, the linkage success rate increased to 99.6% based on analysis of approximately 18,000 records. Of approximately 600 un-matched records, nearly half had received a newborn screen. Approximately 8% of un-matched records were due to parental refusal of newborn screening. Nine children received an initial screen as a result of this study; one was confirmed as having sickle cell trait. CONCLUSIONS: We have demonstrated that a freely available record linkage software, Link Plus, can be used to successfully match records of MCH databases thereby providing an opportunity for further research and quality assurance investigations.


Asunto(s)
Certificado de Nacimiento , Recolección de Datos/métodos , Nacimiento Vivo , Registro Médico Coordinado/métodos , Tamizaje Neonatal , Estudios Transversales , Registros Electrónicos de Salud , Estudios de Seguimiento , Humanos , Recién Nacido , Internet/organización & administración , Nacimiento Vivo/epidemiología , Michigan/epidemiología , Tamizaje Neonatal/organización & administración , Sistemas de Identificación de Pacientes , Proyectos Piloto , Desarrollo de Programa , Evaluación de Programas y Proyectos de Salud , Sistema de Registros , Programas Informáticos/normas , Integración de Sistemas
7.
Science ; 221(4607): 268-71, 1983 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-17815195

RESUMEN

A ground-based search for stratospheric chlorine monoxide was carried out during May and October 1981 with an infrared heterodyne spectrometer in the solar absorption mode. Lines due to stratospheric nitric acid and tropospheric carbonyl sulfide were detected at about 0.2 percent absorptance levels, but the expected 0.1 percent lines of chlorine monoxide in this same region were not seen. Stratospheric chlorine monoxide is less abundant by at least a factor of 7 than is indicated by in situ measurements, and the upper limit for the integrated vertical column density of chlorine monoxide is 2.3 x 10(13) molecules per square centimeter at the 95 percent confidence level. These results imply that the release of chlorofluorocarbons may be significantly less important for the destruction of stratospheric ozone than is currently thought.

8.
Plant Dis ; 91(8): 1059, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30780467

RESUMEN

Kluyveromyces marxianus var. marxianus, a causal agent of onion (Allium cepa L.) soft rot, was originally isolated from Walla Walla sweet onion bulbs grown in Oregon and subsequently isolated from onion throughout the southeast Washington onion-growing area, but was not found to be infecting dry bulb storage onions grown in central Washington (1). During September of 2001, a yeast was isolated from dry storage onion bulbs (cv. Teton) grown under sprinkler irrigation in central Washington, exhibiting soft rot symptoms and identified to be K. marxianus var. marxianus (2). Koch's postulate was completed using cv. Teton bulbs surface disinfested with 0.5% NaOCl for 2 min. This isolate and four isolates of Kluyveromyces marxianus var. marxianus (1) were cultured on potato dextrose agar and resuspended to an OD600 = 0.3 (approximately 105 CFU/ml). One-half of a milliliter of each isolate was inoculated to onion using the cut bulb method with three replicates and incubated in a moist chamber at 25°C for 7 days. Onion slices inoculated with the new isolate exhibited soft rot symptoms similar to those caused by the known isolates while no symptoms were observed for the water control. The yeast reisolated from symptomatic tissue was confirmed to be K. marxianus var. marxianus (2). The identification of K. marxianus var. marxianus infecting dry bulb storage onions grown in the Columbia Basin is of interest because the disease can be confused with bacterial soft rot and could become a serious problem in this important storage onion-growing region. References: (1) D. A. Johnson et al. Plant Dis. 72:359, 1988. (2) N. J. W. Kreger-van Rig, ed. The Yeasts: A Taxonomic Study. Elsevier, Amsterdam, 1984.

9.
Biomed Opt Express ; 8(8): 3828-3841, 2017 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-28856053

RESUMEN

The measurement of optical scattering as a function of angle, goniometry, can provide a wealth of information about tissue. The goniometry technique described here measures the intensity profile at the pupil planes of two microscope objectives with a scattering sample between them. The maximum observable scattering angle is extended by employing off-axis illumination. This configuration permits several advantages including: i) rapid measurement of scattering into 4π sr to characterize the entire scattering phase function in isotropic tissue, ii) sensitivity to axially asymmetric scattering from anisotropic fibrous tissue, iii) selective interrogation of small regions within spatially inhomogenous tissue, iv) concurrent measurement of scattering coefficient µs , and v) measurement of wavelength dependent scattering properties via spectrally tunable source. The instrument is validated by comparing measurements of microsphere suspensions to the Mie scattering solution. Instrument capabilities are demonstrated with samples of rat brain and mouse eye tissues.

10.
Mycologia ; 97(2): 464-73, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16396354

RESUMEN

A new species of Phacidiopycnis associated with pome fruits is described. The fungus causes fruit rot on apples during storage and is associated with a twig dieback and canker disease of crabapple trees and dead twigs of pear trees. To characterize the biology of the fungus and compare it with Ph. piri, the type species of the genus, effects of nine media and light on mycelial growth and pycnidial production, mycelial growth in response to temperature and mode of conidial germination in response to nutrient were determined. Apple-juice agar, pear-juice agar, prune-juice agar, potato-dextrose agar (PDA) and malt-extract agar, Czapek-Dox agar and oatmeal agar (OMA) favored mycelial growth. Cornmeal agar (CMA) did not favor mycelial growth. Light effect on pycnidial formation was medium dependent. Abundant pycnidia with mature conidia formed in 14 d old PDA and OMA cultures at 20 C, regardless of light, whereas none or very few pycnidia formed on other media in the dark. Fluorescent light stimulated formation of pycnidia except on CMA. The fungus grew at -3-25 C, with optimum growth at 15-20 C. Conidia germinated either by forming germ tubes or less often by budding. Budding of conidia occurred in 1 and 10% pear-juice solutions but not in 100% pear-juice solution. Six isolates of Ph. washingtonensis from different species of pome fruits had identical ITS sequences. The sizes of the ITS region were the same for both Ph. washingtonensis and Ph. piri, and four polymorphic nucleotide sites were found in the ITS region between Ph. washingtonensis and Ph. piri. The similarity in ITS sequences between these two taxa is confirmatory evidence for the erection of the new species of Phacidiopycnis associated with pome fruits we describe here.


Asunto(s)
Ascomicetos/clasificación , Ascomicetos/aislamiento & purificación , Malus/microbiología , Pyrus/microbiología , Ascomicetos/citología , Ascomicetos/fisiología , Medios de Cultivo , ADN de Hongos/química , ADN de Hongos/genética , ADN Espaciador Ribosómico/química , ADN Espaciador Ribosómico/genética , Datos de Secuencia Molecular , Micelio/citología , Micelio/crecimiento & desarrollo , Fotograbar , Fotomicrografía , Polimorfismo Genético , Análisis de Secuencia de ADN , Homología de Secuencia de Ácido Nucleico , Esporas Fúngicas , Temperatura , Washingtón
11.
Mycologia ; 97(1): 25-32, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16389953

RESUMEN

Sphaeropsis pyriputrescens, the causal agent of Sphaeropsis rot of pears and apples, is a recently described species. In this study the effects of culture media, temperature, water potential, pH and light on mycelial growth and pycnidial production of S. pyriputrescens were evaluated. Apple juice agar and pear juice agar were most suitable for mycelial growth of all six isolates tested. Cornmeal agar was not suitable for either mycelial growth or pycnidial production. The fungus grew from -3 to 25 C, with optimum growth at 20 C and no growth at 30 C. The fungus grew at water potential as low as -5.6 MPa on potassium chloride-amended potato-dextrose agar (PDA). Hyphal extension was not observed at -7.3 MPa after 10 d incubation, but growth resumed when the inoculum plugs were placed on PDA. The fungus grew at pH 3.3-6.3 and optimum growth was at pH 3.3-4.2. No mycelial growth was observed at pH above 7.2 after 10 d incubation, but growth resumed when the inoculum plugs were transferred onto PDA. Regardless of medium tested, few pycnidia formed at 20 C in the dark. Pycnidial production was enhanced significantly by fluorescent light, but continuous light appeared to reduce pycnidial production, depending on the medium. Oatmeal agar (OMA) was most suitable for production of pycnidia and conidia. Pycnidia that formed on 3 wk old OMA cultures at 20 C under 12 h light/12 h dark produced abundant conidia, and the technique is recommended for inoculum production.


Asunto(s)
Ascomicetos/crecimiento & desarrollo , Medios de Cultivo , Malus/microbiología , Enfermedades de las Plantas/microbiología , Pyrus/microbiología , Agar , Ascomicetos/metabolismo , Ascomicetos/patogenicidad , Ambiente , Concentración de Iones de Hidrógeno , Luz , Técnicas Microbiológicas , Micelio/metabolismo , Temperatura , Agua
12.
Clin Pharmacol Ther ; 32(2): 270-6, 1982 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7094513

RESUMEN

Two osmotically driven, controlled-release dosage forms of indomethacin were evaluated in a multiple-dose crossover study in 12 healthy subjects. Following equivalent daily doses, less frequent dosing of both controlled-release forms resulted in plasma concentration profiles that are more uniform than those following capsule regimens. After the first day, morning predose plasma levels wer significantly higher for the controlled-release treatments. Renal clearances were similar between days and among treatments. Total urinary recoveries were comparable for all regimens.


Asunto(s)
Indometacina/metabolismo , Preparaciones de Acción Retardada , Formas de Dosificación , Estudios de Evaluación como Asunto , Humanos , Indometacina/administración & dosificación , Cinética , Distribución Aleatoria
13.
Clin Pharmacol Ther ; 66(4): 358-66, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10546919

RESUMEN

OBJECTIVE: To evaluate the effect of regular-strength grapefruit juice, a cytochrome P4503A4 (CYP3A4) inhibitor, on the pharmacokinetics of a commonly prescribed regimen of oral lovastatin. METHODS: In a randomized crossover study, 16 healthy subjects received a single 40 mg dose of lovastatin in the evening after each consumed an 8-ounce glass of regular-strength grapefruit juice or water with breakfast for 3 consecutive days. The effect of the same grapefruit juice and water regimen on the pharmacokinetics of midazolam (2 mg oral dose given 1 hour after the third day of grapefruit juice and water) was used as a positive control in the same subjects. Plasma concentrations of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors were determined by an enzyme inhibition assay, and concentrations of lovastatin, lovastatin acid, and midazolam were determined by liquid chromatography-tandem mass spectrometry. RESULTS: The area under the plasma concentration-time profiles (AUC) and maximum plasma concentrations (Cmax) of HMG-CoA reductase inhibitors increased slightly (-30% for each) after consumption of grapefruit juice. Similar effects on AUC and Cmax (approximately 40% increase for each) were noted after analysis of samples of hydrolyzed plasma (which converts inactive lactones to active hydroxy acid species). The AUC and Cmax values for lovastatin approximately doubled in the presence of grapefruit juice, whereas the same parameters for lovastatin acid increased 1.6-fold. Grapefruit juice caused the AUC for midazolam to increase by a factor of approximately 2.4. CONCLUSIONS: Daily consumption of a glass of regular-strength grapefruit juice has a minimal effect on plasma concentrations of HMG-CoA reductase inhibitors (approximately 30% to 40% increase) after a 40 mg evening dose of lovastatin.


Asunto(s)
Anticolesterolemiantes/sangre , Bebidas , Citrus , Inhibidores de Hidroximetilglutaril-CoA Reductasas/sangre , Lovastatina/sangre , Adulto , Análisis de Varianza , Anticolesterolemiantes/administración & dosificación , Área Bajo la Curva , Estudios Cruzados , Interacciones Alimento-Droga , Cromatografía de Gases y Espectrometría de Masas , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/administración & dosificación , Lovastatina/administración & dosificación , Masculino , Valores de Referencia
14.
Arch Neurol ; 50(3): 265-8, 1993 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8442705

RESUMEN

OBJECTIVE: A retrospective study was performed to delineate the clinical characteristics of symptomatic unruptured aneurysms. DESIGN: Patient histories, operative reports, and angiograms in 111 patients with 132 unruptured aneurysms were reviewed. SETTING: Tertiary care university hospital. PATIENTS: One hundred eleven patients with 132 unruptured intracranial aneurysms were studied. There were 85 women and 26 men, with a mean age of 51.2 years (age range, 11 to 77 years). Many patients were referred by community neurologists and neurosurgeons for further evaluation and neurosurgical management. RESULTS: Fifty-four symptomatic patients were identified. Group 1 (n = 19; mean aneurysm diameter, 2.1 cm) had acute symptoms: ischemia (n = 7), headache (n = 7), seizure (n = 3), and cranial neuropathy (n = 2). Group 2 (n = 35; mean aneurysm diameter, 2.2 cm) had chronic symptoms attributed to mass effect: headache (n = 18), visual loss (n = 10), pyramidal tract dysfunction (n = 4), and facial pain (n = 3). Group 3 (n = 57; mean aneurysm diameter, 1.1 cm) had asymptomatic aneurysms. CONCLUSIONS: Acute severe headache, comparable to subarachnoid hemorrhage headache, but without nuchal rigidity, was associated with the following mechanisms: aneurysm thrombosis, localized meningeal inflammation, and unexplained. Unruptured aneurysms may be misdiagnosed as optic neuritis or migraine, or serve as a nidus for cerebral thromboembolic events. Internal carotid artery and posterior circulation aneurysms were more likely to cause focal symptoms from mass effect than were anterior cerebral artery and middle cerebral artery aneurysms. Weeks to years may elapse before their diagnosis. The absence of subarachnoid blood does not exclude an aneurysm as a cause for acute or chronic neurologic symptoms.


Asunto(s)
Aneurisma Intracraneal , Enfermedad Aguda , Adolescente , Adulto , Anciano , Enfermedades de las Arterias Carótidas/complicaciones , Enfermedades de las Arterias Carótidas/diagnóstico , Enfermedades de las Arterias Carótidas/patología , Arteria Carótida Interna , Niño , Enfermedad Crónica , Femenino , Cefalea/etiología , Humanos , Aneurisma Intracraneal/complicaciones , Aneurisma Intracraneal/diagnóstico , Aneurisma Intracraneal/patología , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
15.
Neurology ; 52(9): 1908-10, 1999 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-10371546

RESUMEN

The authors report a new side effect of the dopamine agonists pramipexole and ropinirole: sudden irresistible attacks of sleep. Eight PD patients taking pramipexole and one taking ropinirole fell asleep while driving, causing accidents. Five experienced no warning before falling asleep. The attacks ceased when the drugs were stopped. Neurologists who prescribe these drugs and patients who take them should be aware of this possible side effect.


Asunto(s)
Antiparkinsonianos/efectos adversos , Conducción de Automóvil , Indoles/efectos adversos , Enfermedad de Parkinson/tratamiento farmacológico , Sueño/efectos de los fármacos , Tiazoles/efectos adversos , Vigilia/efectos de los fármacos , Anciano , Anciano de 80 o más Años , Antiparkinsonianos/uso terapéutico , Benzotiazoles , Humanos , Indoles/uso terapéutico , Masculino , Persona de Mediana Edad , Pramipexol , Tiazoles/uso terapéutico
16.
J Clin Pathol ; 33(10): 926-35, 1980 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-7430358

RESUMEN

A system of processing the laboratory data of a busy haematology department serving a teaching group of hospitals and the general practitioners of the district is described. The system, which has been in routine use for over two years, is based on a dedicated CTL8030 computer sited in the laboratory utilising Lynwood visual display units (VDUs) for both input and access to the data files. Data from the Coulter 'S' is fed by an interface to the computer and to other data handling modules. Manual test results are entered via VDUs, mainly by laboratory staff who also validate all data. Access is available to all data for answering telephone requests. Data are retained on the disc file for 48 hours only, and cumulative reporting was not planned into the system as deliberate policy. Quality control of the Coulter 'S' output is maintained both throughout the day and retrospectively at the end of each working day using both whole blood patient blood transfusion profiles, a record of blood and product usage, worksheets, quality control information, end-of-day listing in alphabetical order plus statistical information for administrative purposes. Since its introduction the system has been remarkably free from breakdown as a result of hardware failure. A number of fail safe/fallbacks have been included in the system.


Asunto(s)
Análisis Químico de la Sangre , Computadores , Pruebas Hematológicas , Recuento de Células Sanguíneas , Pruebas de Coagulación Sanguínea , Tipificación y Pruebas Cruzadas Sanguíneas , Transfusión Sanguínea , Presentación de Datos , Humanos , Hierro/sangre , Control de Calidad
17.
J Clin Pharmacol ; 32(2): 136-40, 1992 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-1613123

RESUMEN

Twelve healthy male volunteers received single market-image 40-mg oral doses of lovastatin and simvastatin (both lactone prodrugs), or pravastatin (a beta-hydroxyacid) at 1 week intervals in a three-way crossover study to quantify HMG-CoA reductase inhibitors in plasma. Multiple plasma samples were collected up to 24 hours after the dose and assayed for active and total HMG-CoA reductase inhibitors. After equal oral doses, higher plasma concentrations of HMG-CoA reductase inhibitory activity after pravastatin than after either lovastatin of simvastatin (2-3 fold greater area under the concentration-time curve) suggest a greater potential availability of pravastatin-related inhibitory activity to peripheral tissues.


Asunto(s)
Inhibidores de Hidroximetilglutaril-CoA Reductasas , Lovastatina/análogos & derivados , Lovastatina/farmacocinética , Pravastatina/farmacocinética , Administración Oral , Adulto , Esquema de Medicación , Humanos , Masculino , Simvastatina
18.
J Clin Pharmacol ; 41(6): 612-9, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11402629

RESUMEN

Montelukast, a leukotriene receptor antagonist, has demonstrated efficacy and tolerability in the treatment of asthma in patients age 6 years and older. The purpose of this open, one-period, multicenter population pharmacokinetic study was to identify a chewable tablet (CT) dose of montelukast for administration to children ages 2 to 5 years with asthma, yielding a single-dose pharmacokinetic profile (area under the plasma concentration-time curve [AUC]) comparable to that of the 10 mg film-coated tablet (FCT) dose in adults. Because patient numbers were small and the volume of blood that could be collected from individual 2- to 5-year-old patients was limited, a population pharmacokinetic approach was used to estimate population AUC (AUCpop). The 4 mg CT dose of montelukast was well tolerated and yielded an AUCpop (2721 ng.h/mL) similar to that of the adult AUCpop (2595 ng.h/mL) observed after a 10 mg FCT dose. These results support the selection of a 4 mg once-daily CT dose of montelukast for future efficacy and safety studies in children ages 2 to 5 years with asthma.


Asunto(s)
Acetatos/administración & dosificación , Acetatos/farmacocinética , Antiasmáticos/administración & dosificación , Asma/tratamiento farmacológico , Quinolinas/administración & dosificación , Quinolinas/farmacocinética , Acetatos/efectos adversos , Acetatos/uso terapéutico , Adulto , Antiasmáticos/efectos adversos , Antiasmáticos/farmacocinética , Antiasmáticos/uso terapéutico , Área Bajo la Curva , Niño , Preescolar , Ciclopropanos , Formas de Dosificación , Femenino , Humanos , Antagonistas de Leucotrieno/administración & dosificación , Antagonistas de Leucotrieno/efectos adversos , Antagonistas de Leucotrieno/farmacocinética , Antagonistas de Leucotrieno/uso terapéutico , Masculino , Quinolinas/efectos adversos , Quinolinas/uso terapéutico , Sulfuros
19.
J Clin Pharmacol ; 40(11): 1274-9, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11075313

RESUMEN

Potential for inhibition of CYP3A activity by simvastatin, an HMG-CoA reductase inhibitor, was evaluated in 12 healthy male subjects who received placebo or 80 mg of simvastatin, the maximal recommended dose, once daily for 7 consecutive days. On day 7, an intravenous injection of 3 microCi [14C N-methyl]erythromycin for the erythromycin breath test (EBT) was coadministered with a 2 mg oral solution of midazolam. The values for percent 14C exhaled during the first hour (for EBT) and the pharmacokinetic parameters of midazolam (AUC, Cmax, t1/2) were not affected following multiple once-daily oral doses of simvastatin 80 mg. The 95% confidence interval was 0.97 to 1.18 for EBT and 0.99 to 1.23 for midazolam AUC. In addition, the total urinary recoveries of midazolam and its 1'-hydroxy metabolites (free plus conjugate) obtained from both treatments were not statistically different (p > 0.200). These data demonstrate that multiple dosing of simvastatin, at the highest recommended clinical dose, does not significantly alter the in vivo hepatic or intestinal CYP3A4/5 activity as measured by the commonly used EBT and oral midazolam probes.


Asunto(s)
Hidrocarburo de Aril Hidroxilasas , Inhibidores Enzimáticos del Citocromo P-450 , Eritromicina/farmacocinética , Inhibidores de Hidroximetilglutaril-CoA Reductasas/farmacología , Midazolam/farmacocinética , Oxidorreductasas N-Desmetilantes/antagonistas & inhibidores , Simvastatina/farmacología , Administración Oral , Adulto , Pruebas Respiratorias , Estudios Cruzados , Citocromo P-450 CYP3A , Humanos , Masculino , Método Simple Ciego
20.
J Clin Pharmacol ; 41(5): 573-81, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11361054

RESUMEN

Two randomized, two-period crossover studies were conducted to evaluate the effects of repeat oral dosing of troglitazone (Study I) and pioglitazone (Study II) on the pharmacokinetics of plasma HMG-CoA reductase inhibitors following multiple oral doses of simvastatin and of simvastatin on the plasma pharmacokinetics of troglitazone (Study I) in healthy subjects. In both studies, each subject received two treatments. Treatment A consisted of once-daily oral doses of troglitazone 400 mg (Study I) or pioglitazone 45 mg (Study II) for 24 days with coadministration of once-daily doses of simvastatin 40 mg (Study I) or 80 mg (Study II) on Days 15 through 24. Treatment B consisted of once-daily oral doses of simvastatin 40 mg (Study I) or 80 mg (Study II) for 10 days. In Study I, the area under the plasma concentration-time profiles (AUC) and maximum plasma concentrations (Cmax) of HMG-CoA reductase inhibitors in subjects who received both troglitazone and simvastatin were decreased modestly (by approximately 30% for Cmax and approximately 40% for AUC), but time to reach Cmax (tmax) did not change, as compared with those who received simvastatin alone. Simvastatin, administered orally as a 40 mg tablet daily for 10 days, did not affect the AUC or tmax (p > 0.5) but caused a small but clinically insignificant increase (approximately 25%) in Cmax for troglitazone. In Study II, pioglitazone, at the highest approved dose for clinical use, did not significantly alter any of the pharmacokinetic parameters (AUC, Cmax, and tmax) of simvastatin HMG-CoA reductase inhibitory activity. For all treatment regimens, side effects were mild and transient, suggesting that coadministration of simvastatin with either troglitazone or pioglitazone was well tolerated. The modest effect of troglitazone on simvastatin pharmacokinetics is in agreement with the suggestion that troglitazone is an inducer of CYP3A. The insignificant effect of simvastatin on troglitazone pharmacokinetics is consistent with the conclusion that simvastatin is not a significant inhibitor for drug-metabolizing enzymes. The lack of pharmacokinetic effect of pioglitazone on simvastatin supports the expectation that this combination may be used safely.


Asunto(s)
Cromanos/sangre , Cromanos/farmacología , Inhibidores de Hidroximetilglutaril-CoA Reductasas/farmacología , Hipoglucemiantes/farmacología , Simvastatina/sangre , Simvastatina/farmacología , Tiazoles/sangre , Tiazoles/farmacología , Tiazolidinedionas , Administración Oral , Adulto , Análisis de Varianza , Área Bajo la Curva , Cromanos/efectos adversos , Intervalos de Confianza , Estudios Cruzados , Esquema de Medicación , Interacciones Farmacológicas , Femenino , Cefalea/inducido químicamente , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/sangre , Hipoglucemiantes/sangre , Masculino , Persona de Mediana Edad , Pioglitazona , Simvastatina/efectos adversos , Tiazoles/efectos adversos , Troglitazona
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