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1.
BMC Pregnancy Childbirth ; 22(1): 238, 2022 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-35321664

RESUMEN

BACKGROUND: Preconception care (PCC) is care prior to conception to optimize parental health, and health of the future child, through biomedical and behavioral changes. Providing PCC to all women with a wish to conceive will improve perinatal health. PCC is especially important for women with a chronic disease, such as inflammatory bowel disease (IBD) and rheumatic diseases (RD). At present PCC is not part of routine care for these women. The aim of this study is to identify facilitators and barriers on a patient and professional level regarding the provision of PCC in women with IBD and RD. METHODS: An explorative survey study among women with IBD and RD, their treating physicians and obstetric professionals was performed. Patients with a wish to conceive, pregnant women or those with a recent pregnancy (< 1 year ago) visiting the outpatient clinic of a secondary and tertiary hospital and involved physicians and obstetric professionals were eligible. RESULTS: A total of 71% of the IBD patients (n = 22/31) and 35% of the RD patients (n = 20/58) received a PCC consultation. PCC consultation was considered easy to enter, short in time and patients felt comfortable. Patients (71% IBD; 62% RD) preferred a personal PCC consultation with their disease specific specialist together with an obstetrician. Patients specifically wanted to receive information about the safety of medication use and disease activity following delivery. Of the included healthcare professionals 67% (n = 31) agreed PCC was applicable to their patients. Main barrier to providing PCC was lack of time and unavailability of professionals. In total 41% (n = 16) of obstetric professionals felt they had the knowledge and skills to provide PCC compared to 33% (n = 1) and 75% (n = 3) of gastroenterologists and rheumatologists, respectively. CONCLUSION: Lack of awareness and urgency for the effectuation can be seen as important barriers for implementation of PCC. Due to the explorative nature generalisation of the results is not allowed. In the future, adaptation of the curricula of healthcare professionals by implementing interventions for pregnancy planning and preparation will generate awareness. Modelling of the impact of PCC might prove useful in resolving the lack of urgency for PCC realization.


Asunto(s)
Enfermedades Inflamatorias del Intestino , Atención Preconceptiva , Enfermedades Reumáticas , Enfermedad Crónica , Femenino , Humanos , Enfermedades Inflamatorias del Intestino/terapia , Atención Preconceptiva/métodos , Embarazo , Enfermedades Reumáticas/terapia , Centros de Atención Terciaria
2.
Environ Monit Assess ; 161(1-4): 11-27, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19184491

RESUMEN

A conditional time-averaged gradient (COTAG) system has been developed to provide direct long-term (weekly to monthly) average flux gradient measurements for a range of trace gases, between land and atmosphere. Over daily periods, atmospheric conditions can range from high stability, where the vertical gradients of ambient concentration are enhanced due to very small diffusivity, to highly unstable conditions, in which concentration gradients are small due to the intense turbulent activity of the surface layer. The large vertical gradients generated by high stability would bias the estimate of the actual flux: to avoid this, the COTAG system samples conditionally, within a carefully refined range of stability. A comparison with a continuous flux gradient system suggested that the removal of stable conditions from the sampling period does not substantially modify the evaluation of the long-term fluxes.


Asunto(s)
Monitoreo del Ambiente/economía , Monitoreo del Ambiente/métodos , Compuestos de Amonio Cuaternario/análisis , Dióxido de Azufre/análisis , Modelos Teóricos
3.
J Crohns Colitis ; 14(7): 888-895, 2020 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-31974546

RESUMEN

BACKGROUND AND AIMS: There is paucity of data on safety and efficacy of anti-tumour necrosis factor [TNF] in elderly inflammatory bowel disease [IBD] patients. We aimed to compare the long-term treatment failure rates and safety of a first anti-TNF agent in IBD patients between different age groups [<40 years/40-59 years/≥60 years]. METHODS: IBD patients who started a first anti-TNF agent were identified through IBDREAM, a multicentre prospective IBD registry. Competing risk regression was used to study treatment failure, defined as time to drug discontinuation due to adverse events [AEs] or lack of effectiveness, with discontinuation due to remission as a competing risk. RESULTS: A total of 895 IBD patients were included; 546 started anti-TNF at age <40 [61.0%], 268 at age 40-59 [29.9%], and 81 at age ≥60 [9.1%]. Treatment failure rate was higher in the two older groups (subhazard rate [SHR] age ≥60 1.46, SHR age 40-59 1.21; p = 0.03). The SHR in the elderly [>60] was 1.52 for discontinuation due to AEs and 1.11 for lack of effectiveness. Concomitant thiopurine use was associated with a lower treatment failure rate (SHR 0.78, 95% confidence interval [CI] 0.62-0.98, p = 0.031). Serious adverse event [SAE] rate, as well as serious infection rate, were significantly higher in elderly IBD patients [61.2 versus 16.0 and 12.4 per 1000 patient-years, respectively] whereas the malignancy rate was low in all age groups. CONCLUSIONS: Elderly IBD patients starting a first anti-TNF agent showed higher treatment failure rates, but concomitant thiopurine use at baseline was associated with lower failure rates. Elderly IBD patients demonstrated higher rates of SAEs and serious infections.


Asunto(s)
Adalimumab/uso terapéutico , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Infliximab/uso terapéutico , Inhibidores del Factor de Necrosis Tumoral/uso terapéutico , Adalimumab/efectos adversos , Adolescente , Adulto , Factores de Edad , Anciano , Deprescripciones , Quimioterapia Combinada , Femenino , Humanos , Inmunosupresores/uso terapéutico , Infliximab/efectos adversos , Masculino , Mercaptopurina/análogos & derivados , Mercaptopurina/uso terapéutico , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Sistema de Registros , Inducción de Remisión , Insuficiencia del Tratamiento , Inhibidores del Factor de Necrosis Tumoral/efectos adversos , Adulto Joven
4.
Child Care Health Dev ; 35(4): 440-53, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19638021

RESUMEN

PURPOSE: To review the quality and utility of currently available self-report generic quality of life (QOL) and health-related quality of life (HRQOL) measures for use with children and adolescents with human immunodeficiency virus and/or acquired immunodeficiency syndrome (HIV/AIDS). METHODS: Literature searches were conducted to identify QOL and HRQOL measures developed for, adapted for, or otherwise used with paediatric and adolescent populations with HIV/AIDS. The quality of measures (i.e. item generation techniques, instrument properties including reliability, validity and responsiveness) were compared and critically evaluated. RESULTS: Nineteen QOL/HRQOL measures were identified. Item content was generated from the respondent (adult) population in only eight (42%) measures. Seventeen (90%) measures reported internal reliability in the accepted range between 0.70 and 0.90 and four (21%) reported reproducibility statistics in this range. Although validity was reported for 19 (100%) measures, only six (32%) showed evidence for three or more properties, with construct validity being the most commonly reported aspect. The authors of eight (42%) measures reported evidence for responsiveness. CONCLUSIONS: While almost all measures reviewed demonstrated adequate psychometric properties, only one-third demonstrated all aspects of validity, and less than half demonstrated responsiveness. None included paediatric or adolescent populations with HIV/AIDS in their development, neglecting to obtain input from target respondents in item generation to determine what health-related and daily functioning factors are of importance to them. Despite noted limitations, the AUQUEI or the SWED-QUAL appear the best currently available generic measure, and the MQOL-HIV the preferred disease-specific measure, at least for use with older adolescents/young adults.


Asunto(s)
Infecciones por VIH/psicología , Calidad de Vida , Perfil de Impacto de Enfermedad , Adolescente , Niño , Preescolar , Métodos Epidemiológicos , Estado de Salud , Humanos , Psicometría
5.
Meat Sci ; 82(3): 399-404, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20416700

RESUMEN

Twenty-nine crossbred boars were used to evaluate the effects of live weight and processing on the sensory attributes and concentrations of androstenedione and androstenone (boar taint) in boar meat. Boars were stratified by litter across six weight group endpoints (90.9, 95.5, 100.0, 104.5, 109.1, and 113.6kg). Back fat and longissimus muscle from the lumbar region were used for androstenone determination, proximate analysis and sensory evaluation. Hams were cured for sensory analysis and were used to determine androstenone concentrations. Androstenone as an off-flavor did not differ (P>0.05) among treatments for longissimus lean or cured hams and was found to be in the "threshold" to "none detected" range. Back fat androstenone concentration was positively correlated (P<0.05) to hot carcass weight, however, lean androstenone concentration was not (P>0.05). No relationship was found (P>0.05) between androstenone concentration and days on feed, average daily gain or androstenedione concentration. Additionally, further processing decreased androstenone concentration by approximately 29%.

6.
Meat Sci ; 71(1): 52-61, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22064051

RESUMEN

Thirty-six USDA Select complexus, latissimus dorsi, rhomboideus, serratus ventralis (SEV), splenius, subscapularis, supraspinatus (SUS), and triceps brachii (TRB) muscles were studied. Muscles were assigned to one of four treatments: control, marinated, needle-pumped, and vacuum-tumbled to reach 10% brine pick-up after treatment. The solution was formulated to have 0.5% of sodium chloride and 0.4% of sodium tripolyphosphate in the end product. Steaks from the SEV, SUS, and TRB muscles were cooked on a grill and the other five muscles were oven-roasted whole, all of them cooked to an internal temperature of 71°C. Sensory evaluations and Warner-Bratzler shear force (WBSF) determinations were conducted immediately after cooking (Day-1), and after being cooked and stored frozen for 60 days (Day-60). For the Day-60 evaluation, samples were reheated using a microwave oven. The needle-pumped treatment reduced WBSF values compared to the control in 3 out of 8 muscles (P<0.05). The marinated treatment appeared to have the greatest influence on juiciness and was different from the control in 7 of 8 muscles (P<0.05). Comparing treated muscles to the control, tenderness was increased in 4 out of 8 muscles when needle pumped (P<0.05). Brine treatment reduced sensory detected connective tissue only in 2 of 8 muscles. More off-flavors were detected by the panel for marinated samples from six of eight muscles. All muscles had lower values for WBSF, less connective tissue and off-flavors, and higher juiciness, overall tenderness, and beef flavor intensity on Day-1 than Day-60. The needle-pumped method was slightly superior to the marinated and vacuum-tumbled treatments even though the differences were not always consistent. But, regardless of the application method, palatability traits were generally enhanced by brine treatments.

7.
Meat Sci ; 70(2): 347-56, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22063492

RESUMEN

The objective of this study was to identify a set of explanatory variables for Warner-Bratzler shear force and myofibril fragmentation indices after 7, 14, and 21d of aging; and sensory tenderness after 14d of aging of steaks from Brahman cattle. Insoluble collagen was negatively associated (P<0.001) with all tenderness traits across aging periods, and regression coefficients ranged from 5.69±0.49 to 9.12±0.29N for Warner-Bratzler shear force. The effect of lean color score (P<0.05) in analyses of unadjusted traits was diminished when data were adjusted for contemporary group (calves of the same sex, fed in one pen, and slaughtered the same day). Insoluble collagen may be of special importance and offer a unique opportunity to improve palatability of steaks from purebred Brahman cattle.

8.
Psychol Bull ; 120(2): 272-92, 1996 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8831298

RESUMEN

The purpose of this review is to extend the existing application of the frontal lobe hypothesis of cognitive aging beyond the limited work on inhibitory control (F. N. Dempster, 1992) to include memory processes supported by the prefrontal cortex. To establish a background for this analysis, I review existing models of prefrontal cortex function and present a synthesized model that includes a general function of temporal integration, supported by 4 specific processes: prospective memory, retrospective memory, interference control, and inhibition of prepotent responses. I found the frontal lobe hypothesis to perform well, with the exception of an inability to account for age-related declines in item recall and recognition memory, possibly a result of age-related declines in medial temporal function.


Asunto(s)
Envejecimiento/fisiología , Cognición/fisiología , Memoria/fisiología , Corteza Prefrontal/fisiología , Anciano , Envejecimiento/psicología , Mapeo Encefálico , Humanos , Inhibición Neural/fisiología , Pruebas Neuropsicológicas , Psicofisiología , Valores de Referencia
9.
J Mol Neurosci ; 6(2): 141-6, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-8746452

RESUMEN

Aberrant expression of the amyloid precursor protein (APP) gene may contribute to the beta-amyloid deposition seen in Alzheimer's disease and Down syndrome patients. Genomic DNA was isolated from human brain tissue and digested with HpaII, an enzyme sensitive to CpG methylation. Southern-blot analysis revealed the absence of methylation at a site in the APP gene of an Alzheimer's disease subject. This site was methylated in a nondemented subject and a subject with a non-Alzheimer's type of dementia (Pick's disease). This is the first report of an epigenetic defect in an Alzheimer's disease patient and the observation suggests that hypomethylation of the APP gene may be one of several factors contributing to aberrant gene expression in Alzheimer's disease.


Asunto(s)
Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/metabolismo , Precursor de Proteína beta-Amiloide/genética , Encéfalo/metabolismo , Lóbulo Temporal/metabolismo , Anciano , Anciano de 80 o más Años , Precursor de Proteína beta-Amiloide/biosíntesis , Autopsia , ADN/química , Demencia/genética , Demencia/metabolismo , Fosfatos de Dinucleósidos/análisis , Femenino , Expresión Génica , Humanos , Metilación , Valores de Referencia , Mapeo Restrictivo
10.
Aliment Pharmacol Ther ; 20(11-12): 1329-36, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15606395

RESUMEN

BACKGROUND: Ciprofloxacin is effective in perianal Crohn's disease but after treatment discontinuation symptoms reoccur. Infliximab is effective but requires maintenance therapy. AIM: To evaluate the effect of combined ciprofloxacin and infliximab in perianal Crohn's disease. METHODS: A double-blind placebo-controlled study was conducted. Patients were randomly assigned to receive 500-mg ciprofloxacin twice daily or a placebo for 12 weeks. All patients received 5-mg/kg infliximab in week 6, 8 and 12 and were followed for 18 weeks. Primary end-point was clinical response, defined as a 50% or greater reduction from baseline in the number of draining fistulae. Secondary end-points were the change in Perianal Disease Activity Index and hydrogen peroxide enhanced three-dimensional endoanal ultrasonography findings. Analysis was by intention-to-treat. RESULTS: Twenty-four patients were included but two discontinued treatment. At week 18, response was 73% (eight of 11) in the ciprofloxacin group and 39% (five of 13) in the placebo group (P = 0.12). Using logistic regression analysis patients treated with ciprofloxacin tended to respond better (OR = 2.37, CI: 0.94-5.98, P = 0.07). The Perianal Disease Activity Index score only improved (P = 0.008) in the ciprofloxacin group. Three-dimensional endoanal ultrasonography improved in three patients with a clinical response. CONCLUSIONS: A combination of ciprofloxacin and infliximab tended to be more effective than infliximab alone.


Asunto(s)
Antiinfecciosos/administración & dosificación , Anticuerpos Monoclonales/administración & dosificación , Ciprofloxacina/administración & dosificación , Enfermedad de Crohn/tratamiento farmacológico , Fármacos Gastrointestinales/administración & dosificación , Fístula Rectal/tratamiento farmacológico , Adolescente , Adulto , Enfermedad de Crohn/diagnóstico por imagen , Método Doble Ciego , Quimioterapia Combinada , Endosonografía/métodos , Femenino , Estudios de Seguimiento , Humanos , Infliximab , Masculino , Persona de Mediana Edad , Fístula Rectal/diagnóstico por imagen , Resultado del Tratamiento
11.
Am J Clin Pathol ; 101(5): 661-4, 1994 May.
Artículo en Inglés | MEDLINE | ID: mdl-8178775

RESUMEN

Inflammatory myopathies are a group of acquired disorders with histologic features of inflammation and nonspecific myopathic changes in the muscle fibers. Up to 25% of patients with clinical features of polymyositis reportedly have no inflammatory changes in their muscle biopsy specimens, but the absence of inflammatory infiltrates does not exclude an inflammatory myopathy. However, whether the lack of inflammation is caused by sampling variation or by a total lack of demonstrable inflammation in a particular patient has been unclear in the literature. The authors diagnosed polymyositis in six patients who underwent percutaneous muscle biopsy using a Bergstrom needle. Through one skin incision, the needle was inserted into different areas within the muscle compartment, obtaining three or four concurrent specimens from each patient. In all cases of needle biopsy, adequate tissue was obtained for histochemical and electron microscopic examination. All patients tolerated the procedure well and resumed normal daily activities the morning after biopsy. Although we saw inflammatory changes in at least one biopsy specimen from each patient, one or more of the remaining specimens contained no evidence of inflammation. This illustrates that inflammatory infiltrates can be focal in polymyositis. Because a specific diagnosis of inflammatory myopathy cannot be made in the absence of demonstrable inflammation, the diagnostic yield of multiple percutaneous needle biopsy specimen is potentially higher than that of the traditional single biopsy specimen obtained with the open surgical method.


Asunto(s)
Miositis/patología , Adulto , Biopsia con Aguja , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad , Músculos/patología
12.
Brain Res ; 352(2): 161-8, 1985 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-4027661

RESUMEN

Age- and diabetes-related neuronal degenerative changes were morphometrically evaluated in the arcuate (ARC) and ventromedial (VMH) hypothalamic nuclei of control (+/?) and diabetic (db/db) C57BL/KsJ mice between 4 and 16 weeks of age. By 4 weeks of age, (db/db) mice exhibited marked obesity and hyperglycemia relative to controls. An increase in the population of degenerated ARC neurons was detected at 8 weeks of age in (db/db) mice relative to (+/?) animals. By 16 weeks of age, a significant increase in the number of degenerated VMH neurons in (db/db) mice was found, relative to controls. In addition, the neuronal density (neurons/mm2 area of nucleus) of both the ARC and VMH nuclei was found to be depressed in (db/db) mice, relative to controls, by 16 weeks of age. These data suggest that the normal degenerative loss of ARC and VMH neurons that occurs with age in normal mice is enhanced in the (db/db) mouse. These findings suggest that a functional alteration in hypothalamic nuclei which are recognized to modulate autonomic, pancreatic and pituitary activity may be associated with the onset or expression of the diabetic condition in the C57BL/KsJ (db/db) mouse.


Asunto(s)
Núcleo Arqueado del Hipotálamo/patología , Diabetes Mellitus Experimental/patología , Núcleo Hipotalámico Ventromedial/patología , Factores de Edad , Animales , Glucemia/análisis , Diabetes Mellitus Experimental/sangre , Diabetes Mellitus Experimental/genética , Femenino , Genotipo , Ratones , Ratones Endogámicos C57BL
13.
Psychol Aging ; 5(4): 520-9, 1990 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-2278675

RESUMEN

Three experiments were conducted to examine age differences in memory for telephone numbers by adults ranging from 18 to 85 years of age. In the first 2 studies, using visual simultaneous presentation, age declines in immediate recall were evident on 10-digit numbers, but not on 3-digit numbers. With 7-digit numbers, the youngest group performed significantly better than the oldest (70-85 years) group. In the second study, more marked age declines occurred when subjects had to redial a number after a busy signal. The third experiment replicated the observed aging pattern with auditory sequential presentation. Also, chunked presentation of local telephone numbers resulted in high performance for old and young in sequential recall. The findings were discussed in relation to task processing demands and practical issues related to telephone number recall.


Asunto(s)
Envejecimiento/psicología , Memoria , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Memoria a Corto Plazo , Recuerdo Mental , Persona de Mediana Edad , Teléfono
14.
Psychol Aging ; 8(1): 81-6, 1993 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8461119

RESUMEN

This study examined the role of retrieval and encoding mechanisms in the magnitude of age differences in the recall of subject-performed tasks (SPTs). Eighty older (60-79 years old) and 80 younger adults (18-26 years old) were tested in 1 of 4 conditions by varying modality at both encoding and retrieval. The role of list organization in reducing age differences in SPT recall was also examined. The results suggested that older adults' SPT recall improves when motor processing is enhanced by list organization. Age differences in recall were reduced for an organized list when motor processing occurred during retrieval or encoding, but age differences in recall of an unorganized list remained under most conditions. Discrepant results in the literature concerning the magnitude of age differences in SPT recall could be due in part to differences in list characteristics, such as organization, that have not been fully explored.


Asunto(s)
Envejecimiento/psicología , Atención , Recuerdo Mental , Destreza Motora , Desempeño Psicomotor , Adolescente , Adulto , Anciano , Imagen Corporal , Femenino , Humanos , Masculino , Persona de Mediana Edad , Retención en Psicología , Semántica
15.
Psychol Aging ; 7(1): 72-82, 1992 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-1558708

RESUMEN

Gerontologists have long been concerned with the impact of individual-difference factors on memory. This study used a large sample (N = 2,495) of adult volunteers aged 18 to 90 years to determine if a set of individual-difference variables--vocabulary, education, depression, gender, marital status, and employment status--mediates the effects of aging on a wide range of laboratory-analogue tests of everyday memory. The data indicated that age was consistently the most significant predictor of memory performance, followed by vocabulary and gender. Vocabulary totally mediated age effects on a prose memory measure, and partial mediation of aging effects--primarily by vocabulary and gender--was observed on 5 other memory tests. These data suggest that when health samples of volunteers serve as research subjects, these individual differences can affect some memory test scores, but age remains the best overall predictor of memory performance.


Asunto(s)
Envejecimiento/psicología , Individualidad , Recuerdo Mental , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Aprendizaje Discriminativo , Femenino , Humanos , Masculino , Memoria a Corto Plazo , Persona de Mediana Edad , Pruebas Neuropsicológicas , Reconocimiento Visual de Modelos , Análisis de Regresión , Retención en Psicología
16.
Psychol Aging ; 16(2): 240-50, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11405312

RESUMEN

This research examined the impact of goal-setting conditions on memory beliefs and performance among older and younger adults. After baseline recall and assessment of beliefs, participants were assigned to goal-setting, goals plus feedback, or control. Then, additional recall trials were followed by repeated memory beliefs assessments. For both younger and older adults, performance, motivation, and self-efficacy were affected positively by goal-setting. The impact of goals plus feedback was mixed and varied as a function of age and dependent measure. Success rates for reaching memory goals, which were low for the older adults, may have been a factor in these results. Adults' self-set recall goals were predicted initially by baseline performance and self-efficacy. On the final trial, goals were predicted by last trial performance, self-efficacy, and control beliefs.


Asunto(s)
Envejecimiento/psicología , Objetivos , Conocimiento Psicológico de los Resultados , Recuerdo Mental , Motivación , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Memoria , Autoeficacia
17.
Environ Pollut ; 75(1): 53-9, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-15092049

RESUMEN

Fluxes of NO, NO2 and O3 were determined over a drained marshland pasture in south-east England by using flux-gradient techniques. Nitric oxide was found to be emitted at rates of up to 40 ng m(-2) s(-1), the rate of emission being related to the magnitude of the eddy diffusivity. Nitrogen dioxide deposited at rates of up to 90 ng m(-2) s(-1) under the control of stomatal resistance, a clear diurnal cycle being observed. Minimum canopy resistance was of the order of 80 s m(-1). Ozone deposition was also controlled by stomatal resistance, the minimum canopy resistance being around 100 s m(-1) and fluxes reaching a maximum of 220 ng m(-2) s(-1). Corrections made to NO and NO2 fluxes to compensate for chemical reactions showed flux divergences of the order of 30% for NO and NO2, but these were not statistically significantly different from the measured fluxes. The pasture was found to be a net sink for nitrogen in the form of NOx.

18.
Diagn Cytopathol ; 5(1): 3-8, 1989.
Artículo en Inglés | MEDLINE | ID: mdl-2721351

RESUMEN

Lipoid pneumonia (LP) is an uncommon entity with the characteristic radiographic features and histologic findings of alveoli filled with vacuolated, lipid-laden histiocytes. We questioned whether bronchoalveolar lavage (BAL) could be useful in the confirmation of LP. We examined lipid stains (oil-red O) in BAL specimens from 18 cases, representing a variety of pulmonary disease states, and compared them with an index case of confirmed LP. The index case of LP had a history of chronic intranasal use of mentholated petrolatum with subsequent x-ray findings of progressive air bronchograms. Positive histochemical confirmation (oil-red O) performed on frozen sections of transbronchial lung biopsy was obtained. Eleven of the non-LP cases had no intracellular staining of BAL macrophages with oil-red O stain, whereas the index case of LP exhibited markedly positive intracytoplasmic staining of macrophages for lipid. The remaining seven cases showed minimal to mild lipid staining with only one other case having moderate staining. This study demonstrates that BAL macrophages from patients with a variety of pulmonary states and without suspected LP do not demonstrate significant staining for intracellular lipids, in contrast with the expected strong positivity of LP. Lipid staining of BAL specimens, although not entirely specific, may be a preferred method for confirming the diagnosis of LP, thereby avoiding more invasive procedures.


Asunto(s)
Líquido del Lavado Bronquioalveolar/análisis , Neumonía por Aspiración/diagnóstico , Neumonía Lipoidea/diagnóstico , Adulto , Anciano , Líquido del Lavado Bronquioalveolar/citología , Femenino , Humanos , Lípidos/análisis , Masculino , Persona de Mediana Edad , Neumonía Lipoidea/diagnóstico por imagen , Tomografía Computarizada por Rayos X
19.
Diagn Cytopathol ; 2(4): 330-7, 1986 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-2431849

RESUMEN

Five cases of chordoma, diagnosed by fine-needle aspiration (FNA) biopsy, are presented. Four cases were histologically confirmed, and in one, immunocytochemical and ultrastructural studies were performed on both the aspirate and tissue specimen. Four cases presented as sacral masses, while in the fifth case, a destructive lesion of the clivus extended into the soft tissues of the lateral neck. A spectrum of cytomorphologic features was encountered including the presence of abundant microtissue fragments and cells in a dissociate pattern, often with abundant metachromatic extracellular matrix. Stellate and cuboidal cells often contained intracytoplasmic vacuoles of varying sizes. Intranuclear inclusions, mitotic figures, and anisonucleosis were prominent features of several cases. Immunoperoxidase studies on a single case demonstrated cytoplasmic staining for low- and high-molecular-weight cytokeratins, vimentin, and epithelial membrane antigen, while glial fibrillary acidic protein and carcinoembryonic antigen were negative. Ultrastructural features included the presence of mitochondrial endoplasmic reticulum complexes, occasional desmosome-like junctions, and abundant extracellular matrix adherent to the tumor cells. We believe the cytomorphologic findings are characteristic and, when taken in concert with immunocytochemical and ultrastructural studies, allow differentiation of chordoma from other primary or metastatic neoplasms occurring in bone. As demonstrated in our series, chordoma is often an unsuspected diagnosis. We believe that FNA biopsy of these lesions can lead to a correct preoperative diagnosis and may also be utilized to document recurrence and thus facilitate the evaluation and management of patients with these lesions.


Asunto(s)
Cordoma/patología , Anciano , Biopsia con Aguja , Neoplasias Óseas/patología , Vértebras Cervicales/patología , Cordoma/ultraestructura , Femenino , Histocitoquímica , Humanos , Técnicas para Inmunoenzimas , Queratinas/análisis , Masculino , Microscopía Electrónica , Persona de Mediana Edad , Sacro/patología , Neoplasias de la Columna Vertebral/patología
20.
Diagn Cytopathol ; 2(2): 118-25, 1986.
Artículo en Inglés | MEDLINE | ID: mdl-3522136

RESUMEN

Two cases of malignant thymic neoplasms diagnosed by transthoracic fine-needle aspiration (FNA) biopsy under fluoroscopic and computerized axial tomography (CT) guidance with histologic, immunocytochemical, and ultrastructural confirmation are presented. The clinical and cytomorphologic features of the first case were typical of a malignant thymoma. A characteristic biphasic cell population of benign epithelial cells and mature lymphocytes was seen in Diff-Quik- and Papanicolaou-stained smears from the anterior mediastinal mass and the paravertebral metastasis and was confirmed by histologic examination. Immunoperoxidase studies for T and B cell subsets demonstrated lymphocytes with the thymic lymphocyte phenotype (Leu 6). Electron microscopic (EM) examination revealed epithelial cells with desmosomal attachments, tonofilaments, and extended cell processes along with mature lymphocytes. FNA biopsy of the second case demonstrated features of a thymic carcinoma. Individually scattered and loosely clustered small groups of markedly anaplastic and pleomorphic large cells were seen both in the Diff-Quik- and Papanicolaou-stained smears. EM performed on the FNA specimen demonstrated the poorly differentiated epithelial nature of the malignancy. The mediastinal mass was partially resected and demonstrated an undifferentiated carcinoma staining positively for low-molecular-weight cytokeratin. Ultrastructure demonstrated cell attachments and relationships consistent with carcinoma. The lack of a lung or other extrapulmonary primary tumor was consistent with a thymic carcinoma. These cases demonstrate the value of performing EM and immunocytochemistry on material obtained by fine-needle aspiration, which can aid in establishing the correct diagnosis and facilitate the clinical management of patients with malignant thymic neoplasms.


Asunto(s)
Timoma/patología , Neoplasias del Timo/patología , Adulto , Biopsia con Aguja , Femenino , Histocitoquímica , Humanos , Inmunoquímica , Técnicas para Inmunoenzimas , Masculino , Microscopía Electrónica , Persona de Mediana Edad , Timoma/ultraestructura , Neoplasias del Timo/ultraestructura
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