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PubMed2006

Comparison between color Doppler cineloop- and conventional spectral Doppler-derived maximum velocity and flow in the umbilical vein.

OBJECTIVE: To compare the umbilical venous flow velocity derived from color Doppler cineloop recordings with that derived from conventional spectral Doppler in normal pregnancies. METHOD: In 18 uncomplicated pregnancies between 19 and 39 weeks' gestation, color Doppler was used to find the maximum velocity in the cross-sectional vessel area of a free-floating loop of the umbilical vein. The maximum velocity was determined using the software tool HDI_Lab (Philips Medical Systems) after tracing the vessel area of interest. Conventional spectral Doppler was then used to determine the maximum velocity with the High-Q machine option. The cross-sectional area of the umbilical vein was determined using B-mode imaging and was subsequently used to determine the umbilical volume flow from both Doppler methods. Assuming a parabolic flow profile in the umbilical vein, the mean velocity is equal to half the maximum velocity. The fetal weight was estimated from fetal biometry using the four-parameter Hadlock formula. RESULTS: Maximum velocity was significantly (P = 0.003) higher with color Doppler cineloop (14.3 +/- 2.5 cm/s) compared with spectral Doppler (12.7 +/- 3.2 cm/s). Therefore, using the same cross-sectional area for both methods, the umbilical blood flow was significantly higher (P = 0.001) with color Doppler cineloop (127.9 +/- 59.0 mL/min) than it was with spectral Doppler (112.8 +/- 54.1 mL/min). The umbilical blood flow expressed as volume flow per kg fetal weight was significantly (P = 0.01) higher with color Doppler cineloop (126.0 +/- 57.0 mL/min/kg) than it was with spectral Doppler (115.0 +/- 53.0 mL/min/kg). CONCLUSIONS: Umbilical venous flow velocity derived from color Doppler cineloops is approximately 10% higher than that derived from spectral Doppler-derived velocity. The reduced angle dependence of the color Doppler cineloop technique and the large sampling area of the cross-sectional vessel should allow better determination of the correct maximum velocity in the umbilical vein.

Blood Flow Velocity↗

PubMed1998

A note on the possibility of explaining why a color cannot be both red and green.

To provide a neurophysiological basis for the opponent nature of color vision it has been previously argued that a color cannot be both red and green because color-opponent neurons cannot respond to both red and green at the same time. The present analysis shows that such arguments hinge on the possibility of excluding statements of the kind "a color can be both red and green." For an empirical fact to exclude such statements, these statements would have to be meaningful. However, statements like "a color is both red and green" are not meaningful and are not allowed in our language. Thus, the properties of neurons are not in a position to exclude the possibility of "a color that is both red and green." This means that this attempt to establish a neurophysiological basis for opponent colors is flawed.

Color Perception↗

PubMed1996

Iris color and macular pigment optical density.

The present study was designed to assess the relationship between iris color and macular pigment optical density. Both melanin and carotenoids (responsible for iris color and macular pigment composition, respectively) appear to protect the retina through similar mechanisms and higher concentrations may reduce the incidence of retinal degenerations. To evaluate this relationship, 95 subjects were examined and the following variables were measured: iris color; macular pigment optical density (MP); plasma concentrations of lutein and zeaxanthin and beta-carotene; dietary intake of lutein and zeaxanthin and beta-carotene; and total fat intake. Iris color was determined by self assessment and classified as blue or gray (group I), green or hazel (group II) or brown or black (group III). MP density was measured psychophysically by measuring foveal and parafoveal sensitivities to lights of 460 and 550 nm, using the method of heterochromatic flicker photometry. Plasma carotenoid concentrations were measured using reverse-phase high-performance liquid chromatography. Dietary intake was determined by a detailed food-frequency questionnaire. Despite similarities in diet and in blood concentrations of carotenoids, significant differences in macular pigment density (P < 0.02) were found for different colored irises (group I, n = 38, MP = 0.25; group II, n = 26, MP = 0.32; group III, n = 31, MP = 0.38). The covariation of iris color and MP indicates that past epidemiologic studies have not adequately determined the independent effects of either factor. The relationship of MP and iris color may be the result of one or two factors: the evolution of a shared tendency to accumulate melanin and carotenoids due to similar environmental pressures (e.g. light and oxygen); and/or MP might be depleted due to the tendency for eyes with light irises to transmit more light than eyes with dark irises, thus causing increased oxidative stress.

Adult↗

PubMed1987

Comparison of color sensation in dichoptic and in normal vision.

Color vision in humans is independent over a wide range of the spectral composition of the illuminating light (Young 1807; Hering 1879). The retinex theory accounts for this color constancy by assuming that for each of the three waveband channels determined by the retinal cones a global lightness record of the scene is first computed by the visual system. The three records then serve to generate color at every point (Land 1983). Where do these computations take place? In this report a scene consisting of fourteen colored fields was viewed while one band of wavelengths enters one eye and a different band enters the other (dichoptic case) or while both bands enter both eyes (normal case) under otherwise identical conditions. The perceived color of every field is very similar in both cases although the physical stimulation of the eyes differs. It is also found that color constancy is maintained under dichoptic conditions. The results show that the cortex is crucial for the computation of color.

Adult↗

PubMed1989

Nipple aspirate fluids in adult nonlactating women--lactose content, cationic Na+, K+, Na+/K+ ratio, and coloration.

The presence of lactose in nipple secretions is considered biochemical evidence of breast secretory activity, and has been reported to occur more frequently in white compared to brownish or green colored breast fluid. We studied lactose, Na+, and K+ concentrations, the Na+/K+ ratio, and the coloration of nipple aspirate fluid (NAF) from 49 nonpregnant women. A significant relationship was found between the concentrations of lactose, Na+, and K+, and age and the coloration of NAF. Lactose was present in 22/49 (44.8%) of the NAF samples and declined with age from 100% positivity in women less than or equal to 29 years to 29% in those less than or equal to 35 years. In NAF of deep yellow, brown and green colorations, only traces of lactose were found. Na+ and K+ increased with age and with darker colorations compared to white, pale yellow, or colorless NAF. Lactose was present in NAF samples from both parous and nulliparous younger women, indicating that the breasts of many nonpregnant women respond to prolactin stimulation; hence, lactose may provide a simple marker indicating active physiologic secretory activity of the breast. As reported previously, NAF of darker coloration, containing elevated levels of cholesterol, cholesterol oxidation products, and other substances, suggests retention and impaired reabsorption of these and other products of secretion. Because of the secretion and temporary retention by the breast glands of chemical substances of exogenous and endogenous origin, including mutagens and carcinogens, lactose concentration and coloration of NAF may be useful as markers of secretion and reabsorption in future physiologically based clinical and epidemiologic studies of the pathogenesis of breast disease.

Adult↗

PubMed1988

Association of breast fluid coloration with age, ethnicity, and cigarette smoking.

Nipple aspirates of breast fluid (NAF) occur with different colorations (colorless, white, pale yellow, dark yellow, brown, green, and black). Increasing concentrations of cholesterol, cholesterol 5,6-epoxides, estrogens, and fluorescent products of lipid peroxidation have been positively associated with the dark colorations (dark yellow, brown, green, and black). Because of the absence of data on these variations in breast fluid coloration, we made an exploratory study of their possible associations with age, ethnicity, clinical breast status, and breast cancer risk factors. Dark NAF colorations increased with age among white women from 22.5% at 20-29 years to 49.2% at 50-59 years. Among Chinese and Japanese women, the overall proportion of dark breast fluids was significantly lower (highest proportion 23.5%). A positive association of dark NAF coloration was found with current cigarette smoking (odds ratio = 1.64 [1.04-2.59]). A dose response between amount smoked and dark coloration was found in women less than 50 years of age, with women who smoked more than one pack per day having an odds ratio of 2.31 (1.30-4.67). No significant association of dark NAF was found with the major breast cancer risk factors or with actual benign or malignant breast disease. The dark colorations may represent pigmented products of apocrine gland secretion, lipofuscin complexes of peroxidated lipoprotein, breakdown products of hemoglobin, and possibly, diet-related secretory products.

Adult↗

PubMed1996

Pancreatic arteriovenous malformation with duodenal ulcer. Demonstration by color Doppler ultrasonography.

We report the color Doppler ultrasonography features of arteriovenous malformation (AVM) of the pancreas, a very rare disease. The patient was a 52-year-old man with congenital AVM of the pancreas and a duodenal ulcer that had been resistant to medication. Endoscopic color Doppler ultrasonography (color Doppler EUS) revealed many abnormal color signals showing pulsatile wave form at the portion of the duodenal wall involving the duodenal ulcer. Extracorporeal color Doppler ultrasonography revealed a mosaic-like color signal, caused by turbulent flow, in the portal trunk. Angiography demonstrated a vascular network with extensive proliferation at the pancreatic head and early portal filling. It is possible that the pancreatic AVM had caused the duodenal ulcer. Color Doppler EUS can be a useful modality for detection of vessel abnormalities of the gastrointestinal tract.

Arteriovenous Malformations↗

PubMed1998

The timing of color and location processing in the motor context.

In this study, the use of color and location as stimulus attributes manipulated during a simple action was aimed at comparing how dorsal (location) and ventral (color) features are integrated in action and the timing of their processing. Eighteen subjects were presented with a green dot on a computer screen, which they were required to point at and touch. In 20% of the trials, the location or the color of the target was altered at the onset of movement to this stimulus, requiring the participant to modify the initially programmed response according to specific motor instructions. In the 'location-go' group, the target changed in location and participants were instructed to reach the displaced stimulus by correcting their ongoing movement. In the 'location-stop' and 'color-stop' groups, subjects were instructed to interrupt their movement when the target changed location or color, respectively. Results showed that the latency of the first responses to the perturbation clearly depended on the stimulus attribute and not on the motor instruction tested: the response to color change was obtained about 80 ms later than both conditions involving location change. It is concluded that: (1) color processing is slower than location processing, and (2) the first reactions to the location change occur after the same delay irrespective of the response required from the subject.

Adult↗

PubMedDate not supplied

Enhanced color flow images in small hepatocellular carcinoma.

BACKGROUND: Features of enhanced color flow images in small hepatocellular carcinoma (HCC) are not fully elucidated. The purpose of this study was to clarify the characteristic vascular images in small HCC observed by enhanced color Doppler. METHODS: Enhanced color Doppler using the contrast agent Levovist was performed on 13 patients with HCC smaller than 30 mm. Enhanced color flow appearance was compared with angiographic findings. Time-intensity changes after injection of the contrast agent were analyzed in HCC nodules. RESULTS: Significant improvement in the detection of color flow signals was obtained in small HCC using Levovist, from 33% in precontrast to 92% in postcontrast (p < 0.005). Three patterns of enhanced color flow images, which were related to the angiographic findings, were observed. The time-intensity curve was classified into two types by "time to peak" and "time on plateau" and was associated with the patterns of enhanced images. CONCLUSION: Enhanced color flow imaging promises to be a useful method for evaluating tumor vascularity noninvasively and to contribute to the elucidation of the hemodynamics in small HCC.

Aged↗

PubMed1997

Usefulness of echo-color Doppler in differentiating parathyroid lesions from other cervical masses.

The aim of our study was to clarify possible differential color Doppler US features between parathyroid lesions and other cervical masses. A total of 56 parathyroid lesions in 54 patients with primary hyperparathyroidism were preoperatively examined with color Doppler sonography. Color Doppler flow patterns were compared with those of 72 thyroid nodules and 20 cervical lymph nodes. In 38 parathyroid lesions a correlation between color Doppler patterns and size, location, and pathological findings was performed. Color Doppler sonography showed five vascular distribution patterns: pattern I, absence of flow; pattern II, focal peripheral flow ("vascular pole") with arterial Doppler spectrum; pattern III, peripheral flow; pattern IV, internal flow ("parenchymal pattern"); pattern V, peripheral and intranodular flow. Pattern I was not specific for any cervical lesion considered. Conversely, pattern IV was observed solely in parathyroid lesions, and pattern II was observed in only one nonparathyroid lesion (thyroid nodule). Mixed pattern (pattern V) was observed solely in thyroid nodules. In addition, pattern III was a characteristic finding of thyroid nodules and was observed in only one parathyroid lesion. Color Doppler patterns of the parathyroid masses did not correlate with the size of the lesion or pathological findings, but only with the location of the gland. Our study showed that color Doppler assessment of parathyroid lesions is a useful integration of gray-scale US and may be helpful in distinguishing parathyroid lesions from other cervical masses.

Adenoma↗

PubMed2000

Learning and discrimination of colored papers in jumping spiders (Araneae, Salticidae).

Color discrimination in jumping spiders Hasarius adansoni was examined by heat-avoidance learning in association with colored papers. The arena for the experiment was divided into two halves by a pair of colored papers. The colored papers used in this study were blue, green, yellow, red, white, gray and black. In training sessions, one half of the arena was heated from the bottom by a hot plate, and freely walking spiders were individually trained to avoid the heated half. In subsequent memory tests without heat, they consistently avoided the heat-associated colored papers. We found that jumping spiders could learn blue-green, blue-yellow, blue-red, blue-gray, green-yellow, green-red, green-gray, yellow-red, yellow-gray and red-gray patterns. Moreover, spiders trained with a blue-white pattern, a green-white pattern, a yellow-white pattern or a red-white pattern could discriminate the blue, green, yellow or red from black. It seems that jumping spiders can discriminate the blue, green, yellow and red papers by their hue, although brightness may also be used together with the color cue to discriminate colored papers.

Animals↗

PubMed2005

Re-colorization of museum specimens: a modification of Romhanyi's technique based on pyridine/nicotine hemochromogen reactions.

Romhanyi's technique for preservation and restoration of color in museum specimens is almost unknown outside Hungary. The technique was based on the use of pyridine, nicotine and sodium dithionite (sodium hydrosulphite) for restoring the natural red color of formalin-fixed gross specimens. We developed a modification of the original technique using a mounting medium containing citrate-phosphate-dextrose (CPD) buffer and glycerin to control pH and osmolality. Specimens re-colorized with the modified and improved Romhanyi technique remained stable with a natural red color, and no histological deterioration, for more than 18 years. The technique demonstrates the formation of red colored complexes between nicotine and pyridine and ferro-hemochromes such as hemoglobin, myoglobin and other cytochromes in tissues, giving specimens a natural color. The modified technique enables further improvement for the old process of re-colorization of museum specimens. In addition, it opens up new methods for demonstration of nicotine, pyridine and their analogues in biological tissues.

Color↗

PubMed2004

Priority of color over scent during flower visitation by adult Vanessa indica butterflies.

Most flower visitors innately prefer a particular color and scent, and use them as cues for flower recognition and selection. However, in most cases, since color and scent serve as a combined signal, not only does the preference for an individual cue, but also the preference hierarchy among different cues, influence their flower visitation. In the present study, we attempted to reveal (1) the chromatic and (2) the olfactory cues that stimulate flower visiting, and (3) the preference hierarchy between these cues, using the naive adult butterfly Vanessa indica. When we offered 12 different-colored (six chromatic and six achromatic) paper flower models, V. indica showed a color preference for yellow and blue. When we examined the proboscis extension reflex (PER) of V. indica towards 16 individual compounds identified in the floral scents from two nectar plants belonging to the family Compositae, Taraxacum officinale and Cirsium japonicum, six compounds were found to have relatively high PER-eliciting activities, including benzaldehyde, acetophenone, and (E+Z)-nerolidol. When we combined color and scent cues in two-choice bioassays, where butterflies were offered flower models that were purple (a relatively unattractive color), the models scented with these active compounds were significantly more attractive than the odorless controls. In addition, synthetic blends mimicking the floral scents of T. officinale and C. japonicum (at doses equivalent to that of ten flowers) enhanced the number of visits to the scented models. However, the effect of odorizing was not conspicuous in parallel bioassays when yellow flower models were used, and the butterflies also significantly preferred odorless yellow models to scented purple models. These results demonstrate that V. indica depends primarily on color and secondarily on scent during flower visitation.

Animals↗

PubMed2005

Evaluation of arterial blood flow in esophageal varices via endoscopic color Doppler ultrasonography with a galactose-based contrast agent.

BACKGROUND: We examined the usefulness of endoscopic color Doppler ultrasonography, using Levovist in evaluating the arterial blood flow, in patients with esophageal varices. METHODS: The study involved 110 patients with esophageal varices who were examined using endoscopic color Doppler ultrasonography (ECDUS). We compared vessel images detected by pre-contrast ECDUS with those detected by enhanced ECDUS. We evaluated the detection rate of the pulsatile wave, and measured systolic velocity and end-diastolic velocity. We calculated the resistance index (RI), which demonstrates the resistance of peripheral vessels in arterial flow. RESULTS: Color flow images of the pulsatile wave were obtained by pre-contrast ECDUS in 3 (2.7%) of the 110 patients. Color flow images of the pulsatile waves were obtained in 40 (36.4%) of the 110 patients by enhanced ECDUS using Levovist. That is, by using Levovist, a pulsatile wave could be delineated in 37 patients in whom pulsatile waves were previously undiagnosed via pre-contrast ECDUS. Color flow images of the pulsatile waves were detected in 37 (37.7%) of the 98 F2 varices and in 3 (25.0%) of the 12 F3 varices. Color flow images of the pulsatile wave were detected in 35 (40.2%) of the 87 red color (RC)(+) varices, and in 5 (21.7%) of the 23 RC(++) or RC (+++) varices. Next, we calculated the RI of the pulsatile wave, obtained by enhanced ECDUS using Levovist, in 40 patients. The RI ranged from 0.49 to 0.83 (mean, 0.67 +/- 0.09); there were nine patients with RIs of less than 0.60, and all 9 of these patients had both F2 and RC(+) type varices (100%). CONCLUSIONS: Levovist contrast in ECDUS examinations suggests that arterial flow is involved in the formation of esophageal varices.

Adult↗

PubMed2006

Computation of color and brightness differences by rabbit visual cortex neurons.

Extracellular recording of the activity of 54 neurons in the rabbit visual cortex in responses to substitutions of eight colored and eight monochromatic stimuli in pairs was studied. Stimuli were uniform flashes of light displayed on an SVGA monitor and illuminated the whole retina. The responses of phasic neurons showed an initial discharge (50-90 msec from the moment of the change in stimulus), associated with the brightness or color difference between the stimuli. These "discrimination discharges" were used to construct an 8 x 8 matrix for each neuron, showing the mean number of spikes per sec in responses to changes in different pairs of stimuli. Processing of the matrix by factor analysis identified the major factors determining the axes of the sensory space. A brightness space with only two dimensions, with darkness and brightness orthogonal axes, was seen for 30% of neurons. A four-dimensional color space was seen in 22% of neurons, with two color and two achromatic axes. The sensory space of these neurons was similar to the spaces obtained by analyzing the early components of visual evoked potentials in rabbits induced by changes in color stimuli and behavioral operant responses in conditioned reflex color differentiation. The fundamental coincidence of the sensory spaces obtained by different methods identifies the general nature of the principle of vector coding and the existence of special neuronal mechanisms for detection of color and brightness differences in the visual field.

Action Potentials↗

PubMed1993

The revised Stroop color-naming task in social phobics.

Information processing was examined in a sample of social phobic individuals using a revised version of the Stroop color-naming task. In the first of two experiments, the response latencies of social phobics and matched community controls were compared when color-naming socially threatening words, physically threatening words and color words. Social phobics demonstrated greater response latencies regardless of type of stimulus word and additional interference in color-naming social threat words compared to the control group. The second experiment examined the cognitive structural change that has been hypothesized to accompany successful treatment of individuals with an anxiety disorder. Social phobics who were treated with cognitive-behavioral group therapy, phenelzine or pill placebo were classified as treatment responders or nonresponders, and their latencies to color-naming on the Stroop task were compared. Treatment responders showed a significant reduction in latencies to color-name social threat words (vs matched control words) while nonresponders did not. This effect was not demonstrated with color words or physically threatening words. Clinical implications and future research directions are discussed.

Adult↗

PubMed1992

Effects of home bleaching preparations on composite resin color.

The lightening of teeth is done professionally by exposure to warm hydrogen peroxide solutions or at home with an active bleaching gel of perhydrol urea or carbamide peroxide. This study compared the effects of two commercial bleaching gels on the color of composite resin with those in a previous study using the dental office technique. Commercial composite resins test specimens were exposed to the bleaching gels or water (control) for 312 hours at 37 degrees C at 100% relative humidity. Color change value was calculated with before-and-after solution exposure L*a*b* color values. ANOVA (alpha = 0.01) revealed no differences in the color of the specimens after use of the test solutions. All color change values were less than 2 or the normal limit of visual acuity. No visual color change was evident for these composite resins. The at-home method recorded no shade-altering effects compared with the professional technique, which created a noticeable color change.

Analysis of Variance↗

PubMed1994

Color coding of radiographic changes over time by means of image addition.

Differences between sequential radiographs may be displayed in color if the individual radiographs are transformed into monochromatic images and then added. Information in regions where the radiographs are identical is retained whereas differences are emphasized by the color coding that comes about in a quantitative manner from the gray level values in the sequence of radiographs. By using the three additive primary colors, red, blue, and green, two or three radiographs from a sequence may be added. Every possible state of a bone disease, progression, regression, or any combination, will produce a different and specific color code. Different development cycles are described, and the color coding that appears when color image addition is performed is analyzed. The color addition technique should constitute a useful substitute or alternative to subtraction.

Alveolar Bone Loss↗