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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 181: 286-308, 2017 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-28391158

RESUMEN

The matrix-isolated, mid-infrared spectra of seven acridine-based polycyclic aromatic nitrogen heterocycles (PANHs) have been measured and compared to their non-nitrogen containing parent molecule. The acridine species investigated include acridine, benz[a]acridine, benz[c]acridine, dibenz[a,j]acridine, dibenz[c,h]acridine, dibenz[a,h]acridine and dibenz[a,c]acridine. The previously reported results for 1 and 2-azabenz[a]anthracenes are included for comparison. The experimentally determined band frequencies and intensities are compared with their B3LYP/6-31G(d) values. The overall agreement between experimental and theoretical values is good and in line with our previous investigations. Shifts, typically to the blue, are noted for the C-H out-of-plane (CHoop) motions upon insertion of a nitrogen atom. The formation of a bay region upon addition of additional benzene rings to the anthracene/acridine structure splits the solo hydrogen motions into a bay region solo and an external solo hydrogen, with the bay region solo hydrogen coupling to the quartet hydrogen motions and the external solo hydrogen coupling with the duo hydrogen motions resulting in an extreme decrease in intensity for the CHoop solo hydrogen band when the external hydrogen is replaced by a nitrogen atom. The C-C and C-H in-plane region of this acridine series exhibits the characteristic two fold increase in intensity, noted previously for PANHs. The strong ≈1400cm-1 band, which was identified in the previous PANH study, is noted in several molecular species as well as another strong PANH feature between 1480 and 1515cm-1 for several molecules. The presence of these strong bands appear to be primarily responsible for the two-fold increase in the C-H in-plane region's (1100-1600cm-1) intensity. The C-H stretching region can be characterized by contributions from the solo (bay or external), duo and quartet hydrogens, similar to what was observed in the dibenzopolyacene compounds.

3.
J Nutr Health Aging ; 15(8): 624-30, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21968856

RESUMEN

BACKGROUND: Clinical trials that have assessed the best approach for treating under-nutrition in old age are scarce. OBJECTIVE: To determine the impact of an intensive nutritional intervention program led by a dietitian on the health and nutritional status of malnourished community dwelling older adults. METHODS: Sixty-eight eligible participants (age<75) were randomly assigned to a Dietetic Intervention Treatment (DIT), an intensive nutritional intervention led by a dietitian, or a Medical Treatment (MT), a physician-led standard care group, with an educational booklet regarding dietary requirements and recommendations for older adults. An additional 59 eligible participants who were unable to participate in the randomization were included as a non-randomized "untreated nutrition" group (UNG). RESULTS: Over the 6-month follow-up, the DIT group showed significant improvement in cognitive function (from 25.8±4.5 to 26.8±4, p=0.04), and depression score (from 7.3±3.9 to 5.4±3.9, p=0.04) compared with the change in the other 2 groups. The DIT group showed a significant improvement in intake of carbohydrates (+15% vs. +1% in the MT and +3% in the UNG), protein (+8% vs. +2% in the MT and -3% in the UNG), vitamin B6 (+20% vs. +7% in the MT and +8% in the UNG), and vitamin B1 (+22% vs. +11% in the MT and 0% in the UNG). The DIT group had a significantly lower cost of physician visits than the other 2 groups ($172.1±232.0 vs. $417.2±368.0 in the MT and $428.1±382.3 in the UNG, p=0.005). CONCLUSION: Intensive dietary intervention was moderately effective in lowering cost of services used and improving medical and nutritional status among community dwelling older adults.


Asunto(s)
Trastornos del Conocimiento/prevención & control , Cognición/fisiología , Depresión/dietoterapia , Ingestión de Energía , Educación en Salud/métodos , Desnutrición/dietoterapia , Estado Nutricional , Anciano , Anciano de 80 o más Años , Manejo de Caso , Trastornos del Conocimiento/economía , Depresión/economía , Carbohidratos de la Dieta/administración & dosificación , Proteínas en la Dieta/administración & dosificación , Dietética/métodos , Femenino , Educación en Salud/economía , Humanos , Masculino , Desnutrición/economía , Visita a Consultorio Médico/economía , Nivel de Atención/economía , Tiamina/administración & dosificación , Vitamina B 6/administración & dosificación
4.
Am J Med Genet ; 114(4): 458-65, 2002 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-11992571

RESUMEN

The fragile X syndrome is caused by an unstable CGG repeat sequence in the 5' untranslated region of the X-linked, FMR1 gene. When the number of repeats exceeds 200, the region is hypermethylated and the gene is silenced. The lack of the protein produced by the FMR1 gene, FMRP, causes the fragile X syndrome. Recent evidence suggests that FMR1 alleles with unmethylated long repeat tracks (40-200 repeats) may cause a specific somatic phenotype in women, premature ovarian failure, and may cause variation in the levels of FMR1 mRNA and FMRP. Because FMR1 is known to be involved in the regulation of subset of genes expressed in the brain, we investigated the variation in cognitive and/or behavioral performance among carriers of high repeat alleles. Specifically, we administered cognitive, behavioral, and adaptive performance tests to children identified with high repeat alleles who attended special education classes in Atlanta, Georgia public schools and to those with < 40 repeats drawn from the same population. Overall, we found no significant effect of repeat size and the psychometric measures in our test battery after adjustment for multiple comparisons. All scales were found to be within 1 SD standard deviation of the mean. We did find an intriguing, albeit marginally statistically significant, association in the cognitive profile among males and not females, consistent with an X-linked effect. After adjusting for the overall cognitive abilities score, Verbal Ability scores decreased and Nonverbal Reasoning scores increased with repeat number to a greater extent in males than females. Spatial Ability scores were not associated with repeat number.


Asunto(s)
Cognición , Síndrome del Cromosoma X Frágil/genética , Proteínas del Tejido Nervioso/genética , Proteínas de Unión al ARN , Repeticiones de Trinucleótidos , Adaptación Psicológica , Niño , Femenino , Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil , Humanos , Masculino , Pruebas Neuropsicológicas , Desempeño Psicomotor
6.
Science ; 290(5495): 1325-8, 2000 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-11082054

RESUMEN

High-resolution x-ray observations of the prototype starburst galaxy Messier 82 (M82) obtained with the advanced CCD (charge-coupled device) imaging spectrometer on board the Chandra X-ray Observatory provide a detailed view of hot plasma and energetic processes. Plasma with temperature of about 40,000,000 kelvin fills the inner 1 kiloparsec, which is much hotter than the 1,000,000 to 2,000,000 kelvin interstellar medium component in the Milky Way Galaxy. Produced by many supernova explosions, this central region is overpressurized and drives M82's prominent galactic wind into the intergalactic medium. We also resolved about 20 compact x-ray sources, many of which could be high-mass x-ray binary star systems containing black holes.

7.
J Child Adolesc Psychopharmacol ; 9(2): 99-107, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10461820

RESUMEN

OBJECTIVE: The purpose of this trial was to investigate the short-term safety and efficacy of quetiapine fumarate in the treatment of children and adolescents with autistic disorder (AD). METHOD: This was a 16-week, open-label trial that included 6 male subjects with a mean age of 10.9 +/- 3.3 years. All subjects met the DSM-IV criteria for AD and functioned in the mentally retarded range (mild, n = 2; moderate, n = 3; severe, n = 1). Behavioral ratings were obtained at baseline and every four weeks thereafter. RESULTS: Overall, there was no statistically significant improvement between baseline and endpoint for the group as a whole. Only two subjects completed 16 weeks of treatment and were considered "responders" by the global improvement item of the Clinical Global Impression Scale (CGIS). Dosages ranged from 100 to 350 mg/day (1.6-5.2 mg/kg/day). Subjects dropped out prematurely because of lack of response and sedation, limiting further dose increases (n = 3), and because of a possible seizure during the fourth week of treatment (n = 1). Other significant side effects included behavioral activation, increased appetite and weight gain (range, 0.9 to 8.2 kg). CONCLUSIONS: Quetiapine was poorly tolerated and associated with serious side effects in this clinical population.


Asunto(s)
Antipsicóticos/uso terapéutico , Trastorno Autístico/tratamiento farmacológico , Dibenzotiazepinas/uso terapéutico , Adolescente , Niño , Dibenzotiazepinas/administración & dosificación , Dibenzotiazepinas/efectos adversos , Humanos , Masculino , Estudios Prospectivos , Fumarato de Quetiapina , Aumento de Peso/efectos de los fármacos
8.
Astrophys J ; 513(1 Pt 2): L65-8, 1999 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-11543061

RESUMEN

Long-slit 8-13 micrometers spectroscopy of the nebula around NGC 1333 SVS 3 reveals spatial variations in the strength and shape of emission features that are probably produced by polycyclic aromatic hydrocarbons (PAHs). Close to SVS 3, the 11.2 micrometers feature develops an excess at approximately 10.8-11.0 micrometers and a feature appears at approximately 10 micrometers. These features disappear with increasing distance from the central source, and they show striking similarities to recent laboratory data of PAH cations, providing the first identification of emission features arising specifically from ionized PAHs in the interstellar medium.


Asunto(s)
Astronomía , Medio Ambiente Extraterrestre , Hidrocarburos Policíclicos Aromáticos/análisis , Hidrocarburos Policíclicos Aromáticos/química , Fenómenos Astronómicos , Cationes , Polvo Cósmico , Análisis Espectral
9.
Pediatr Clin North Am ; 45(3): 673-90, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9653444

RESUMEN

Surfactant therapy has significantly reduced mortality, but not morbidity, in the very low birthweight (VLBW) infant. Questions persist as to the edge of viability, the allocation of health care resources for the VLBW infant, and whether or not we are improving survival at the cost of contributing more handicapped individuals to society. Since surfactant alone has not reduced morbidity, other medical and behavioral treatments are being studied that may help to optimize neurodevelopmental outcome in the VLBW infant.


Asunto(s)
Discapacidades del Desarrollo/etiología , Recién Nacido de muy Bajo Peso , Surfactantes Pulmonares/uso terapéutico , Síndrome de Dificultad Respiratoria del Recién Nacido/tratamiento farmacológico , Niño , Análisis Costo-Beneficio , Discapacidades del Desarrollo/prevención & control , Humanos , Recién Nacido , Morbilidad , Surfactantes Pulmonares/economía , Síndrome de Dificultad Respiratoria del Recién Nacido/complicaciones , Síndrome de Dificultad Respiratoria del Recién Nacido/mortalidad , Análisis de Supervivencia , Resultado del Tratamiento
10.
J Autism Dev Disord ; 27(5): 501-17, 1997 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9403369

RESUMEN

Results from ROC curves of items from two scales, the Autism Diagnostic Interview (ADI) and Autism Diagnostic Interview-Revised (ADI-R), operationalizing DSM-IV criteria for autism are presented for 319 autistic and 113 other subjects from 8 international autism centers. Analyses indicate that multiple items were necessary to attain adequate sensitivity and specificity if samples with varying levels of language were considered separately. Although considering only current behavior was generally sufficient when a combination cutoff and additive model was employed, predictive power was highest when history was taken into account. A single set of criteria, as operationalized by individually structured questions in the ADI/ADI-R, was effective in differentiating autism from mental handicap and language impairment in subjects with a range of chronological ages and developmental levels.


Asunto(s)
Trastorno Autístico/diagnóstico , Escalas de Valoración Psiquiátrica/estadística & datos numéricos , Adolescente , Adulto , Factores de Edad , Algoritmos , Trastorno Autístico/psicología , Niño , Trastornos Generalizados del Desarrollo Infantil/diagnóstico , Preescolar , Diagnóstico Diferencial , Femenino , Humanos , Discapacidad Intelectual/diagnóstico , Discapacidad Intelectual/psicología , Inteligencia/clasificación , Pruebas de Inteligencia/estadística & datos numéricos , Masculino , Valor Predictivo de las Pruebas , Sensibilidad y Especificidad
11.
Astrophys J ; 474(2 Pt 1): 735-40, 1997 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-11539404

RESUMEN

Long-slit spectra across the Orion Bar reveal significant differences in the spatial behavior of the components of the 3 microns polycyclic aromatic hydrocarbon (PAH) spectrum. The strong PAH band at 3.29 microns generally decreases exponentially with distance from the ionization front into the molecular cloud (scale height approximately 12"), although excesses appear approximately 10" and 20" behind the ionization front, close to layers of H2 and CO emission, respectively. The 3.40 microns PAH feature separates into two components with very different spatial distributions. The main component (at 3.395 microns), along with the 3.51 microns band and the PAH plateau (3.3-3.6 microns), shows excess emission approximately 10" and approximately 20" behind the ionization front, stronger than the excesses in the 3.29 microns band. The extra component of the 3.40 microns band, which peaks at approximately 3.405 microns, has a spatial distribution very similar to the H2 emission. Aromatic C-H stretches in PAHs most likely produce the 3.29 microns feature. Aliphatic C-H stretches in either attached methyl side-groups or superhydrogenated PAHs, or perhaps both, could produce the complicated spectral and spatial structure at 3.40 microns.


Asunto(s)
Astronomía/métodos , Medio Ambiente Extraterrestre , Hidrocarburos Policíclicos Aromáticos , Astronomía/instrumentación , Hidrógeno , Espectrofotometría Infrarroja/métodos
12.
Astrophys J ; 461(1 Pt 1): 210-22, 1996 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-11539170

RESUMEN

We have obtained 5-8 micrometers spectra of the Galactic center from the Kuiper Airborne Observatory at resolving powers of approximately 50, approximately 150, and approximately 300. These spectra show absorption features at 5.5, 5.8, 6.1, and 6.8 micrometers. Together with previously observed features in the 3 micrometers region, these features are compared with laboratory spectra of candidate materials. The 3.0 and 6.1 micrometers features are due to the OH stretching and bending variations of H2O and are well fitted by water of hydration in silicates (e.g., talc). The 3.0 micrometer band is equally well fitted by ice mixtures containing 30% H2O, but such mixtures do not provide a good fit to the observed 6.1 micrometer band. The 3.4 and 6.8 micrometers features are identified with the CH stretching and deformation modes in CH2 and CH3 groups in saturated aliphatic hydrocarbons. The 6.1 micrometer band shows a short wavelength shoulder centered on 5.8 micrometer, attributed to carbonyl (C double bond O) groups in this interstellar hydrocarbon dust component. Finally, the narrow 5.5 micrometer feature is also attributed to carbonyl groups, but in the form of metal carbonyls [e.g., Fe(CO)4]. We have derived column densities and abundances along the line of sight toward the Galactic center for the various identified dust components. This analysis shows that hydrocarbon grains contain only 0.08 of the elemental abundance of C and contribute only a relatively minor fraction (0.1) of the total dust volume. Most of the interstellar dust volume is made up of silicates (approximately 0.6). Small graphite grains, responsible for the 2200 angstroms bump, account for 0.07 of the total dust volume. The remaining one-quarter of the interstellar dust volume consists of a material(s) without strong IR absorption features. Likely candidates include large graphite grains, diamonds, or amorphous carbon grains, which all have weak or no IR active modes. Finally, various models for the origin of the hydrocarbon dust component of the interstellar dust are discussed. All of them face some problems in explaining the observations, in particular, the absence of the spectroscopic signature of hydrocrbon grains in sources associated with molecular clouds.


Asunto(s)
Astronomía/instrumentación , Polvo Cósmico/análisis , Medio Ambiente Extraterrestre , Hidrocarburos/análisis , Aeronaves , Carbono/análisis , Hidrocarburos/química , Hielo/análisis , Modelos Teóricos , Silicatos/análisis , Espectrofotometría Infrarroja , Agua
13.
Neonatal Netw ; 15(2): 5-13, 1996 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8700095

RESUMEN

Managing the care of the very preterm infant can become a maze of diagnoses, treatments, and tests that blur progress and expectations along an infant's extended course in the NICU. Yet the health care environment demands that comprehensive, high-quality, cost-effective care be provided each infant and family entrusted to our care. Critical pathways based on gestational age at birth and postconceptional age throughout the hospital stay facilitate the necessary goal-oriented, interdisciplinary approach to infant care by providing consistency, flexibility, and quality management.


Asunto(s)
Manejo de Caso/organización & administración , Vías Clínicas/organización & administración , Recien Nacido Prematuro , Cuidado Intensivo Neonatal/organización & administración , Factores de Edad , Edad Gestacional , Humanos , Recién Nacido , Grupo de Atención al Paciente
14.
Icarus ; 107: 413-7, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-11539181

RESUMEN

A strong absorption band at 3590 +/- 20 cm-1 (2.790 +/- 0.015 micrometers) has been discovered in the spectrum of Io using the Kuiper Airborne Observatory (KAO). The 2 nu1 + nu3 combination mode of solid SO2 falls at this position. Since SO2 is abundant on Io it must contribute to the new band. However, a band due to H2O was predicted near this frequency in Io's spectrum based on laboratory experiments of H2O:SO2 mixed Io ice analogs which were used to assign the two weak, variable features of 3370 and 3170 cm-1 (2.97 and 3.15 micrometers) to trace amounts of H2O frozen in solid SO2 on Io. The new band probably originates from both SO2 and H2O. Unfortunately, the spectral resolution of the data is insufficient to settle the issue of whether there are two resolvable components.


Asunto(s)
Astronomía/instrumentación , Medio Ambiente Extraterrestre , Hielo/análisis , Júpiter , Dióxido de Azufre/análisis , Agua/análisis , Aeronaves/instrumentación , Radical Hidroxilo/análisis , Espectrofotometría Infrarroja
15.
Pediatr Clin North Am ; 40(5): 937-53, 1993 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8414716

RESUMEN

Advances in neonatology, particularly surfactant, have enabled us to significantly improve mortality in the extremely low-birth-weight prematurely born infant. The impact on morbidity remains less clear but decidedly optimistic as the preponderance of the data currently available suggests that although we have not improved outcome in this high-risk group of infants, neither have we increased the percentage of infants with significant impairments. But overall morbidity remains high, especially for the smallest and earliest survivors. There is a growing body of research that supports the idea that with modification of the stressful impact of the NICU environment on the physiologically unstable and vulnerable premature infant, we may be able to improve developmental outcome. We are already seeing even very small infants extubated at a younger age and ready for discharge home well before their originally anticipated "due date." Within this setting we have unequalled opportunity to positively impact development by caring for the infants in a supportive environment that integrates parents as primary caretakers who are comfortable and competent at the time of the infant's discharge home. Further research endeavors should be enlightening in this regard.


Asunto(s)
Recien Nacido Prematuro/crecimiento & desarrollo , Surfactantes Pulmonares/uso terapéutico , Humanos , Recién Nacido de Bajo Peso , Recién Nacido , Factores de Riesgo , Resultado del Tratamiento
16.
Science ; 262(5130): 86-9, 1993 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-17742963

RESUMEN

Much of the interstellar gas resides in photodissociation regions whose chemistry and energy balance is controlled by the flux of far-ultraviolet radiation upon them. These photons can ionize and dissociate molecules and heat the gas through the photoelectric effect working on dust grains. These regions have been extensively modeled theoretically, but detailed observational studies are few. Mapping of the prominent Orion Bar photodissociation region at wavelengths corresponding to the carbon-hydrogen stretching mode of polycyclic aromatic hydrocarbons, the 1-0 S(1) line of molecular hydrogen, and the J = 1-0 rotational line of carbon monoxide allows the penetration of the far-ultraviolet radiation into the cloud to be traced. The results strongly support the theoretical models and show conclusively that the incident far-ultraviolet radiation field, not shocks as has sometimes been proposed, is responsible for the emission in the Orion Bar.

17.
J Autism Dev Disord ; 22(4): 483-92, 1992 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1483972
19.
Clin Perinatol ; 19(3): 673-94, 1992 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-1382004

RESUMEN

It appears that the survivor of BPD is at risk for neurodevelopmental compromise but not necessarily to any greater extent than are prematurely born infants in general. What appears to be true is that as the neonatal course becomes more complicated, and the birth weight drops, the risk increases. If a BPD survivor sustains a moderate to severe IVH, particularly if accompanied by periventricular leukomalacia, the risk of significant handicap increases substantially. Effects of socioeconomic status (SES) are also important, and become more evident over time with a direct correlation between SES and outcome. Maximizing the environmental conditions while in the special care nursery, and reducing stress on the infant during the illness, may help to reduce risk of a compromised developmental outcome in the survivors. Careful monitoring of oxygen saturation postdischarge may similarly have a positive effect on outcome. Although direct comparability among studies is not possible, it appears that most reports suggest about half the survivors are free of any handicapping condition at follow-up, and about half are either moderately or severely impaired. Cerebral palsy is the most frequently reported handicapping condition. Since the presence or absence of significant IVH is not consistently reported across studies, it is not possible to know if infants who subsequently develop CP sustained a bleed, in addition to BPD, in the neonatal period. In studies in which this is more carefully delineated, that appears to be the case. In studies in which infants with significant hemorrhage were either excluded or dropped out, no survivors with cerebral palsy are reported. Approximately 4% of survivors across all studies reviewed were blind as a result of severe retinopathy of prematurity. Several studies excluded infants who developed significant ROP from their follow-up, so this percentage may be an underestimate of the actual incidence across all BPD survivors. With a greater number of gestationally younger infants surviving, this is one area of handicap that may increase in the years to come. Not all studies report on the presence of sensorineural hearing loss in survivors, but there is the suggestion this may occur perhaps in up to 4% of survivors. This is an area that future research should address. For infants who fall in the moderately handicapped category, typically defined as more than one standard deviation below the mean on a standardized developmental examination, that rating may change over time in either direction.(ABSTRACT TRUNCATED AT 400 WORDS)


Asunto(s)
Displasia Broncopulmonar/complicaciones , Discapacidades del Desarrollo/etiología , Trastornos del Crecimiento/etiología , Displasia Broncopulmonar/epidemiología , Displasia Broncopulmonar/terapia , Niño , Preescolar , Discapacidades del Desarrollo/epidemiología , Dexametasona/uso terapéutico , Estudios de Seguimiento , Trastornos del Crecimiento/epidemiología , Humanos , Incidencia , Lactante , Recién Nacido , Respiración Artificial/efectos adversos , Factores Socioeconómicos , Factores de Tiempo
20.
J Am Acad Child Adolesc Psychiatry ; 31(4): 746-50, 1992 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-1644740

RESUMEN

This report provides preliminary evidence for the efficacy of clomipramine in the treatment of young adults with autistic disorder. Four of five outpatients with autistic disorder showed significant improvement in social relatedness, obsessive compulsive symptoms, and aggressive and impulsive behavior with clomipramine treatment. These findings are consistent with previous evidence, suggesting that serotonin neurotransmission may be relevant to the treatment, and possibly the pathophysiology, of some symptoms of autistic disorder.


Asunto(s)
Trastorno Autístico/tratamiento farmacológico , Clomipramina/uso terapéutico , Adolescente , Adulto , Agresión/efectos de los fármacos , Trastorno Autístico/psicología , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Femenino , Humanos , Masculino , Trastorno Obsesivo Compulsivo/tratamiento farmacológico , Trastorno Obsesivo Compulsivo/psicología , Conducta Social
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