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1.
J Adv Model Earth Syst ; 11(11): 3343-3361, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32025278

RESUMEN

Numerical models have been highly successful in simulating global carbon and nutrient cycles in today's ocean, together with observed spatial and temporal patterns of chlorophyll and plankton biomass at the surface. With this success has come some confidence in projecting the century-scale response to continuing anthropogenic warming. There is also increasing interest in using such models to understand the role of plankton ecosystems in past oceans. However, today's marine environment is the product of billions of years of continual evolution-a process that continues today. In this paper, we address the questions of whether an assumption of species invariance is sufficient, and if not, under what circumstances current model projections might break down. To do this, we first identify the key timescales and questions asked of models. We then review how current marine ecosystem models work and what alternative approaches are available to account for evolution. We argue that for timescales of climate change overlapping with evolutionary timescales, accounting for evolution may to lead to very different projected outcomes regarding the timescales of ecosystem response and associated global biogeochemical cycling. This is particularly the case for past extinction events but may also be true in the future, depending on the eventual degree of anthropogenic disruption. The discipline of building new numerical models that incorporate evolution is also hugely beneficial in itself, as it forces us to question what we know about adaptive evolution, irrespective of its quantitative role in any specific event or environmental changes.

2.
Comput Biol Med ; 69: 44-51, 2016 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-26717240

RESUMEN

We propose a novel computational approach to automatically identify the fetal heart rate patterns (fHRPs), which are reflective of sleep/awake states. By combining these patterns with presence or absence of movements, a fetal behavioral state (fBS) was determined. The expert scores were used as the gold standard and objective thresholds for the detection procedure were obtained using Receiver Operating Characteristics (ROC) analysis. To assess the performance, intraclass correlation was computed between the proposed approach and the mutually agreed expert scores. The detected fHRPs were then associated to their corresponding fBS based on the fetal movement obtained from fetal magnetocardiogaphic (fMCG) signals. This approach may aid clinicians in objectively assessing the fBS and monitoring fetal wellbeing.


Asunto(s)
Feto , Magnetocardiografía/métodos , Tercer Trimestre del Embarazo , Embarazo , Procesamiento de Señales Asistido por Computador , Femenino , Humanos
3.
Food Chem ; 188: 149-60, 2015 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-26041177

RESUMEN

Glucose is an aldosic monosaccharide that is centrally entrenched in the processes of photosynthesis and respiration, serving as an energy reserve and metabolic fuel in most organisms. As both a monomer and as part of more complex structures such as polysaccharides and glucosides, glucose also plays a major role in modern food products, particularly where flavor and or structure are concerned. Over the years, many diverse methods for detecting and quantifying glucose have been developed; this review presents an overview of the most widely employed and historically significant, including copper iodometry, HPLC, GC, CZE, and enzyme based systems such as glucose meters. The relative strengths and limitations of each method are evaluated, and examples of their recent application in the realm of food chemistry are discussed.


Asunto(s)
Técnicas de Química Analítica , Análisis de los Alimentos/métodos , Glucosa/análisis , Glucemia/análisis , Cromatografía de Gases , Cromatografía Líquida de Alta Presión , Electrodos , Electroforesis Capilar , Enzimas
4.
Carbohydr Polym ; 115: 444-7, 2015 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-25439917

RESUMEN

Cereal starch amylose/amylopectin (AM/AP) is critical in functional properties for food and industrial applications. Conventional methods of AM/AP are time consuming and labor intensive making it difficult to screen the large sample sets necessary for evaluating breeding samples and investigating environmental impact on starch development. The objective was to adapt and optimize the iodine binding assay in a 96-well plate format for measurement at both λ 620 nm and λ 510 nm. The standard curve for amylose content was scaled to a 96-well plate format and demonstrated R(2) values of 0.999 and 0.993 for single and dual wavelengths, respectively. The plate methods were applicable over large ranges of amylose contents: high amylose maize starch at 61.7±2.3%, normal wheat starch at 29.0±0.74%, and a waxy maize starch at 1.2±0.9%. The method exhibited slightly greater amylose content values than the Concanavalin A method for normal type starches; but is consistent with cuvette scale iodine binding assays.


Asunto(s)
Amilosa/análisis , Amilosa/química , Técnicas de Química Analítica/métodos , Yodo/química , Calibración , Grano Comestible/química , Almidón/química
5.
J Agric Food Chem ; 61(24): 5715-9, 2013 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-23705643

RESUMEN

Cover crop treatments and nitrogen (N) fertilization rates were investigated for their impact on sorghum grain quality attributes. Sorghum was planted in field plots treated with differing cover cropping systems and fertilization rates. The size (weight and diameter) and hardness of the kernels were influenced by both the cover crop and N rates. The protein content increased as the N rate increased and also with the addition of cover crops to the system. The protein digestibility values and starch granule size distributions were not affected by N rate or the cover cropping treatments. Soil properties were tested to determine relationships with grain quality attributes. The utilization of cover crops appears to increase the protein content without causing a deleterious effect on protein digestibility. The end-product quality is not hampered by the use of beneficial cropping systems necessary for sustainable agriculture.


Asunto(s)
Agricultura/métodos , Productos Agrícolas/crecimiento & desarrollo , Fertilizantes , Compuestos de Nitrógeno/metabolismo , Semillas/crecimiento & desarrollo , Sorghum/crecimiento & desarrollo , Fenómenos Químicos , Conservación de los Recursos Naturales , Productos Agrícolas/química , Productos Agrícolas/metabolismo , Proteínas en la Dieta/análisis , Proteínas en la Dieta/metabolismo , Digestión , Calidad de los Alimentos , Kansas , Fenómenos Mecánicos , Proteínas de Almacenamiento de Semillas/análisis , Proteínas de Almacenamiento de Semillas/biosíntesis , Semillas/química , Semillas/metabolismo , Suelo/química , Sorghum/química , Sorghum/metabolismo , Almidón/análisis , Almidón/metabolismo
6.
Sex Dev ; 5(5): 241-9, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22116535

RESUMEN

Hypospadias is increasingly common, and requires surgery to repair, but its aetiology is poorly understood. The marsupial tammar wallaby provides a unique opportunity to study hypospadias because penile differentiation occurs postnatally. Androgens are responsible for penile development in the tammar, but the majority of differentiation, in particular formation and closure of the urethral groove forming the penile urethra in males, occurs when there is no measurable sex difference in the concentrations of testosterone or dihydrotestosterone in either the gonads or the circulation [corrected]. Phalluses were examined morphologically from the sexually indifferent period (when androgens are high) to well after the time that the phallus becomes sexually dimorphic. We show that penile development and critical changes in the positioning of the urethra occur in the male phallus begin during an early window of time when androgens are high. Remodelling of the urethra in the male occurs between days 20-60. The critical period of time for the establishment urethral closure occurs during the earliest phases of penile development. This study suggests that there is an early window of time before day 60 when androgen imprinting must occur for normal penile development and closure of the urethral groove.


Asunto(s)
Macropodidae/crecimiento & desarrollo , Uretra/anatomía & histología , Uretra/crecimiento & desarrollo , Animales , Femenino , Macropodidae/anatomía & histología , Masculino
7.
Physiol Meas ; 32(2): 263-73, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21252416

RESUMEN

The purpose of fetal magnetoencephalography (fMEG) is to record and analyze fetal brain activity. Unavoidably, these recordings consist of a complex mixture of bio-magnetic signals from both mother and fetus. The acquired data include biological signals that are related to maternal and fetal heart function as well as fetal gross body and breathing movements. Since fetal breathing generates a significant source of bio-magnetic interference during these recordings, the goal of this study was to identify and quantify the signatures pertaining to fetal breathing movements (FBM). The fMEG signals were captured using superconducting quantum interference devices (SQUIDs) The existence of FBM was verified and recorded concurrently by an ultrasound-based video technique. This simultaneous recording is challenging since SQUIDs are extremely sensitive to magnetic signals and highly susceptible to interference from electronic equipment. For each recording, an ultrasound-FBM (UFBM) signal was extracted by tracing the displacement of the boundary defined by the fetal thorax frame by frame. The start of each FBM was identified by using the peak points of the UFBM signal. The bio-magnetic signals associated with FBM were obtained by averaging the bio-magnetic signals time locked to the FBMs. The results showed the existence of a distinctive sinusoidal signal pattern of FBM in fMEG data.


Asunto(s)
Movimiento Fetal/fisiología , Magnetismo/métodos , Movimiento/fisiología , Respiración , Femenino , Humanos , Interpretación de Imagen Asistida por Computador , Magnetoencefalografía , Embarazo , Ultrasonografía Prenatal
8.
Br J Radiol ; 84(1000): 375-9, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21159801

RESUMEN

OBJECTIVES: This study investigates the reliability of femoral neck shaft angle (NSA) measurements made with the software and images available in routine clinical practice. METHODS: Using the Centricity Enterprise™ (GE Healthcare Pty Ltd Piscataway, NJ) picture archiving and communication system (PACS), the NSA of the proximal femur was measured from anteroposterior radiographs of adult hips. 3 independent observers, using a standardised technique, performed a total of 120 measurements. RESULTS: The Pearson's correlation coefficient for the intraobserver agreement was 0.98 (p<0.01) and for interobserver measurements 0.86 (p<0.01). Bland-Altman plots revealed the limits of intraobserver agreement to be ±2.5°, but interobserver limits of agreement to be ±6°. The intraclass correlation coefficient (ICC) was also calculated. The interobserver ICC was 0.62 (0.42-0.78, 95% confidence interval (CI); p<0.001). The intraobserver ICC was 0.98 (0.95-0.99, 95% CI; p<0.001). CONCLUSION: PACS software has many advantages, but when using systems that can display angle measurements to one-tenth of a degree caution must be exercised to ensure that reliability of these measurements is not overestimated. We found that in the context of measuring the NSA of the proximal femur the reliability of the measurement, even under the best conditions, is only ±6° for different observers.


Asunto(s)
Cuello Femoral/diagnóstico por imagen , Articulación de la Cadera/diagnóstico por imagen , Sistemas de Información Radiológica , Tomografía Computarizada por Rayos X/métodos , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Procesamiento de Señales Asistido por Computador , Adulto Joven
9.
Ann Biomed Eng ; 39(3): 964-72, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21140290

RESUMEN

Changes in fetal magnetocardiographic (fMCG) signals are indicators for fetal body movement. We propose a novel approach to reliably extract fetal body movements based on the field strength of the fMCG signal independent of its frequency. After attenuating the maternal MCG, we use a Hilbert transform approach to identify the R-wave. At each R-wave, we compute the center-of-gravity (cog) of the coordinate positions of MCG sensors, each weighted by the magnitude of the R-wave amplitude recorded at the corresponding sensor. We then define actogram as the distance between the cog computed at each R-wave and the average of the cog from all the R-waves in a 3-min duration. By applying a linear de-trending approach to the actogram we identify the fetal body movement and compare this with the synchronous occurrence of the acceleration in the fetal heart rate. Finally, we apply this approach to the fMCG recorded simultaneously with ultrasound from a single subject and show its improved performance over the QRS-amplitude based approach in the visually verified movements. This technique could be applied to transform the detection of fetal body movement into an objective measure of fetal health and enhance the predictive value of prevalent clinical testing for fetal wellbeing.


Asunto(s)
Algoritmos , Diagnóstico por Computador/instrumentación , Diagnóstico por Computador/métodos , Electrodos , Monitoreo Fetal/métodos , Movimiento Fetal/fisiología , Magnetocardiografía/métodos , Diseño de Equipo , Femenino , Humanos , Embarazo , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
10.
Poult Sci ; 89(9): 1802-14, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20709964

RESUMEN

Ammonia is the primary basic gas in the atmosphere and has the most important role in the neutralization of atmospheric acids generated by fossil fuel combustion. The reaction product forms a NH(4)(+) aerosol, which is a major component of atmospheric particulates. These NH(4)(+) particulates are part of atmospheric haze and may be transported long distances from the production site before returning to the surface by dry deposition or scavenged by precipitation. Animal production produces a significant component of anthropogenic NH(3) emissions and the National Academy of Sciences concluded that NH(3) emissions estimates from animal feeding operations have not been characterized sufficiently, leading the US Environmental Protection Agency to institute studies in the United States to obtain NH(3) emissions from animal feeding operations under the US Environmental Protection Agency Air Consent Agreement. The objective of this study is to obtain additional broiler NH(3) emissions estimates using a backward Lagrangian stochastic technique. This technique uses NH(3) concentrations measured upwind and downwind of the farm, wind observations, and atmospheric dispersion model calculations to obtain whole-farm emissions. Ammonia emissions were low at bird placement and increased steadily after about the third week of growth. At the end of the flock (47 d, ~297,000 birds), cumulative emissions for the flock cycle period were 0.016 kg of NH(3).bird(-1).flock(-1). Between-flock emissions, including bird harvest, cleanout, temporary storage of litter outside of the buildings, and downtime (buildings closed), added another 0.003 kg of NH(3).bird(-1).flock(-1). Emissions from this broiler farm were less than from some eastern US broiler farms but were comparable to broiler farms in Europe. Based on the results of this study and a similar winter study at this same farm, total flock wintertime and summertime (flock cycle plus between-flock) NH(3) emissions from this farm represented 7.8 and 8.3% of feed N as NH(3)-N, respectively, or an annual average of 8.1%.


Asunto(s)
Agricultura , Contaminantes Atmosféricos/química , Contaminación del Aire , Amoníaco/química , Pollos/fisiología , Animales , California , Estiércol , Modelos Teóricos , Estaciones del Año , Factores de Tiempo , Viento
11.
Phys Rev E Stat Nonlin Soft Matter Phys ; 80(4 Pt 2): 046213, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19905421

RESUMEN

The Hilbert phase phi(t) of a signal x(t) exhibits slips when the magnitude of their successive phase difference |phi(t(i+1))-phi(t(i))| exceeds pi. By applying this approach to periodic, uncorrelated, and long-range correlated data, we show that the standard deviation of the time difference between the successive phase slips Deltatau normalized by the percentage of slips in the data is characteristic of the correlation in the data. We consider a 50x50 square lattice and model each lattice point by a second-order autoregressive (AR2) process. Further, we model a subregion of the lattice using a different set of AR2 parameters compared to the rest. By applying the proposed approach to the lattice model, we show that the two distinct parameter regions introduced in the lattice are clearly distinguishable. Finally, we demonstrate the application of this approach to spatiotemporal neonatal and fetal magnetoencephalography signals recorded using 151 superconducting quantum interference device sensors to identify the sensors containing the neonatal and fetal brain signals and discuss the improved performance of this approach over the traditionally used spectral approach.


Asunto(s)
Algoritmos , Encéfalo/fisiología , Diagnóstico por Computador/métodos , Electroencefalografía/métodos , Modelos Neurológicos , Diagnóstico Prenatal/métodos , Simulación por Computador , Humanos , Recién Nacido
12.
Physiol Meas ; 30(10): 1051-60, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19738317

RESUMEN

We propose a multi-stage approach using Wavelet and Hilbert transforms to identify uterine contraction bursts in magnetomyogram (MMG) signals measured using a 151 magnetic sensor array. In the first stage, we decompose the MMG signals by wavelet analysis into multilevel approximate and detail coefficients. In each level, the signals are reconstructed using the detail coefficients followed by the computation of the Hilbert transform. The Hilbert amplitude of the reconstructed signals from different frequency bands (0.1-1 Hz) is summed up over all the sensors to increase the signal-to-noise ratio. Using a novel clustering technique, affinity propagation, the contractile bursts are distinguished from the noise level. The method is applied on simulated MMG data, using a simple stochastic model to determine its robustness and to seven MMG datasets.


Asunto(s)
Electromiografía/normas , Magnetismo/normas , Contracción Uterina/fisiología , Electromiografía/métodos , Femenino , Humanos , Magnetismo/métodos , Miografía/métodos , Miografía/normas , Embarazo
13.
Transpl Infect Dis ; 11(5): 454-7, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19558375

RESUMEN

We present a case of fulminant leptospirosis that was acquired in the suburban area by a 48-year-old male renal transplant recipient. He developed acute renal and hepatic failure with profound jaundice. Spirochetes were identified on liver biopsy. Weil's disease was suspected, and the diagnosis was further supported by a positive serum Leptospira interrogans icterohaemorrhagiae antibody titer. Unfortunately, he suffered from recurrent lower gastrointestinal bleeding, had a prolonged hospital course, and eventually succumbed to overwhelming sepsis. This case is the third report to our knowledge of leptospirosis in a renal transplant recipient in the English literature.


Asunto(s)
Trasplante de Riñón/efectos adversos , Leptospira interrogans serovar icterohaemorrhagiae , Leptospirosis/complicaciones , Lesión Renal Aguda/etiología , Biopsia , Resultado Fatal , Humanos , Leptospira interrogans serovar icterohaemorrhagiae/clasificación , Leptospira interrogans serovar icterohaemorrhagiae/aislamiento & purificación , Leptospirosis/microbiología , Hígado/microbiología , Fallo Hepático Agudo/etiología , Masculino , Persona de Mediana Edad , Sepsis/etiología
14.
Foot Ankle Surg ; 15(2): 65-8, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19410171

RESUMEN

BACKGROUND: Hallux valgus is a common forefoot condition, with numerous operations described to correct the deformity. Debate remains as to the relative importance of correcting the position of the sesamoid apparatus. METHODS: Forty-six cases were reviewed. Preoperative and post-operative X-rays were used to measure forefoot width, inter-metatarsal angle (IM), hallux valgus (HV) angle and sesamoid position (Reynolds stations). Satisfaction was assessed via questionnaire. RESULTS: Significant improvements were seen in all radiological parameters. 37/43 patients were satisfied with the result. Comparison between the satisfied and non-satisfied group revealed significant differences in the IM angle (p<0.05) and HV angle (p<0.05). However, patient satisfaction was not associated with post-op sesamoid position or change in sesamoid position (p>0.05). CONCLUSIONS: This study showed that scarf osteotomy, can successfully correct hallux valgus, with high levels of satisfaction. Satisfaction is associated with a greater correction of deformity. Improvement in sesamoid position was not associated with patient satisfaction.


Asunto(s)
Hallux Valgus/cirugía , Huesos Sesamoideos/cirugía , Fenómenos Biomecánicos , Hallux Valgus/diagnóstico por imagen , Humanos , Osteotomía/métodos , Satisfacción del Paciente , Radiografía , Estudios Retrospectivos , Estadísticas no Paramétricas , Encuestas y Cuestionarios , Resultado del Tratamiento
15.
Physiol Meas ; 30(1): N1-10, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19104135

RESUMEN

The design, safety analysis and performance of a fetal visual stimulation system suitable for fetal and neonatal magnetoencephalography studies are presented. The issue of fetal, neonatal and maternal safety is considered and the maximum permissible exposure is computed for the maternal skin and the adult eye. The risk for neonatal eye exposure is examined. It is demonstrated that the fetus, neonate and mother are not at risk.


Asunto(s)
Potenciales Evocados Visuales , Luz , Magnetoencefalografía/instrumentación , Diagnóstico Prenatal/instrumentación , Diseño de Equipo , Femenino , Humanos , Recién Nacido , Magnetoencefalografía/efectos adversos , Exposición Materna , Diagnóstico Prenatal/efectos adversos
16.
Neuroimage ; 43(3): 521-7, 2008 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-18760370

RESUMEN

OBJECTIVE: We propose to use cross-correlation function to determine significant fetal and neonatal evoked responses (ERs). METHODS: We quantify ERs by cross-correlation between the stimulus time series and the recorded brain signals. The statistical significance of the correlation is calculated by surrogate analysis. For validation of our approach we investigated a model which mimics the generation of ERs. The model assumes a fixed latency of the ER and contains two parameters, epsilon and lambda. Whether or not the system responds to a given stimulus is controlled by epsilon. The amount to which the system is excited from the base line (background activity) is governed by lambda. We demonstrate the technique by applying it to auditory evoked responses from four fetuses (21 records) between 27 and 39 weeks of gestational age and four neonates (eight records). RESULTS: The method correctly identified the ER and the latency incorporated in the model. A combined analysis of fetuses and neonates data resulted in a significant negative correlation between age and latency. CONCLUSIONS: The analysis of ER, especially for fetal and newborn recordings, should be based on advanced data analysis including the assessment of the significance of responses. The negative correlation between age and latency indicates the neurological maturation. SIGNIFICANCE: The proposed method can be used to objectively assess the ER in fetuses and neonates.


Asunto(s)
Encéfalo/fisiología , Potenciales Evocados Auditivos/fisiología , Feto/fisiología , Recién Nacido/fisiología , Modelos Neurológicos , Humanos , Magnetoencefalografía
17.
Clin Neuropathol ; 27(1): 13-20, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18257470

RESUMEN

Primary central nervous system (PCNS) diffuse large B-cell lymphoma (DLBCL) is an aggressive form of non-Hodgkin's lymphoma whose growth is restricted to the central nervous system and eye. Primary CNS DLBCL has a poor prognosis relative to other extranodal DLBCL. Recently DLBCL has been subclassified as germinal and non-germinal center B-cell types using microarray. Germinal center B-cell DLBCL is associated with better prognosis compared to non-germinal center B-cell group. The objective of the study was to subcategorize the PCNS DLBCL into germinal center and non-germinal center DLBCL using immunohistochemistry and to correlate its prognostic significance. 21 immunocompetent patients were diagnosed with PCNS DLBCL over last 20 years at William Beaumont Hospital. Clinical data on outcome were collected and their specimens were retrieved. Immunohistochemical staining was done using markers, CD20, CD10, Bcl-6, MUM-1, MIB-1, Bcl-2 and by molecular analysis of the immunoglobulin heavy chain gene (IgH) variable region. Immunohistochemistry showed 1/21 (positive cases/examined cases) for CD10, 19/21 for Bcl-6, 19/21 for MUM-1 and 15/21 for Bcl-2. The expression pattern of CD10(-) MUM-1(+) is corresponded to the non-germinal center DLBCL. The MIB-1 index ranged from 40--80% with a mean of 57%, indicating a high proliferation of lymphoma cells. The IgH gene variable region analysis showed monoclonality in 15 of 21 cases (71%). Primary CNS DLBCL has a non-germinal center B-cell phenotype in majority of cases and has a high Bcl-2 positivity and MIB-1 index. These features might be associated with poor prognosis.


Asunto(s)
Linfocitos B/inmunología , Neoplasias del Sistema Nervioso Central/inmunología , Neoplasias del Sistema Nervioso Central/patología , Linfoma de Células B Grandes Difuso/inmunología , Linfoma de Células B Grandes Difuso/patología , Adolescente , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/análisis , Neoplasias del Sistema Nervioso Central/mortalidad , Cartilla de ADN , Femenino , Humanos , Inmunohistoquímica , Inmunofenotipificación , Estimación de Kaplan-Meier , Activación de Linfocitos/inmunología , Linfoma de Células B Grandes Difuso/mortalidad , Masculino , Persona de Mediana Edad , Pronóstico
18.
Intern Med J ; 38(3): 178-82, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17645502

RESUMEN

BACKGROUND: A recent report has suggested that occult Cushing's syndrome (CS) may be present in a significant number of patients with type 2 diabetes mellitus. The aim of this study was to determine whether any patients in our clinic population with diabetes had this condition. METHODS: One hundred and seventy-one consecutive overweight attendees at the diabetic clinic were enrolled in a study to assess the presence of occult CS. The initial screen was with the 1 mg overnight dexamethasone suppression test and follow-up testing, where indicated was with a 24 h collection for urine-free cortisol. RESULTS: Thirty-one of 171 patients had a positive result from the overnight dexamethasone suppression test. Follow-up testing with 24 h urine-free cortisol reduced the number of patients with positive results to 3. Two of these were shown to have alcoholic pseudo-CS. The third patient has had several high urine-free cortisol results, in the presence of normal scans of pituitary and adrenals. He has no stigmata of CS and is being observed. CONCLUSION: Based on the results of our study, there would appear to be little value in screening type 2 diabetics for CS, in the absence of clinical suspicion.


Asunto(s)
Síndrome de Cushing/diagnóstico , Dexametasona , Diabetes Mellitus Tipo 2/complicaciones , Hidrocortisona/orina , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Síndrome de Cushing/complicaciones , Síndrome de Cushing/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Prospectivos
19.
Opt Lett ; 32(16): 2348-50, 2007 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-17700781

RESUMEN

We present the design, construction, and initial characterization of a multifunctional imaging/scattering spectroscopy system built around a commercial inverted microscope platform. The system enables co-registered brightfield, Fourier-filtered darkfield, and fluorescence imaging; monochromatic angle-resolved scattering measurements; and white-light wavelength-resolved scattering spectroscopy from the same field of view. A fiber-based illumination system provides illumination-wavelength flexibility and a good approximation to a point source. The performance of the system in its various data acquisition modes is experimentally verified using fluorescent microspheres. This multifunctional instrument provides a platform for studies on adherent cells from which the biophysical implications of subcellular light scattering can be studied in conjunction with sensitive fluorescence-based techniques.


Asunto(s)
Luz , Orgánulos/química , Dispersión de Radiación , Microscopía Fluorescente/métodos , Análisis Espectral/métodos
20.
Int J STD AIDS ; 18(5): 308-11, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17524189

RESUMEN

Hormonal changes may be important in the onset and clearance of bacterial vaginosis. We studied vaginal flora and serum oestradiol levels of 55 women at baseline and during hormonal treatment. None developed bacterial vaginosis (BV) from normal vaginal flora, 69% of women had normal flora at baseline increasing to 91% following hormonal treatment. The mean oestradiol level with BV was 39.07 ng/L compared with 176.41 ng/L with normal flora. Non-smokers had a mean oestradiol level of 173.95 ng/L compared with 118.67 ng/L in smokers. Recombinant follicle-stimulating hormone resulted in a mean oestradiol rise of 113.9 ng/L. The mean rise was 330.4 ng/L with improved vaginal flora but only 15.1 ng/L in persistently abnormal or worsening flora. A rise in oestradiol in this group of women was associated with a significant reduction of abnormal flora. Reversion from BV to normal flora was associated with a greater rise in oestradiol than where abnormal flora persisted or worsened. This study supports a possible hormonal influence in the natural history of BV. The lower oestradiol levels in smokers may help explain their increased risk of BV.


Asunto(s)
Estradiol/sangre , Vagina/microbiología , Vaginosis Bacteriana , Adulto , Bacterias/crecimiento & desarrollo , Estradiol/metabolismo , Estrógenos/metabolismo , Estrógenos/uso terapéutico , Femenino , Hormona Folículo Estimulante/uso terapéutico , Humanos , Proyectos Piloto , Proteínas Recombinantes/uso terapéutico , Fumar/efectos adversos , Vagina/efectos de los fármacos , Vagina/fisiología
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