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PubMed2000

[Statistical efficiency of depth discrimination in stereoscopically overlapped and step-edge patterns].

We compared observers' statistical efficiencies of depth discrimination for two stereoscopic patterns: an overlapped pattern where two planes are overlapped at different depths, and a step-edge pattern where two planes are arranged side by side. In both patterns, elements in one plane were differentiated from those in the other plane by color (red vs. green) or orientation (45 deg vs. -45 deg). In the experiment, subjects were required to determine which plane was in front when Gaussian disparity noise was added to both of the elements' disparity values. The results showed that efficiencies were the same level for both patterns when the elements were differentiated by color. On the other hand, efficiencies were lower for the overlapped pattern than the step-edge pattern when the elements were differentiated by orientation regardless of the set size of elements. The patterns which we used were so sparse that the differences between the color and orientation conditions should arise from the process after matching.

Color Perception↗
PubMed2000

Comparison of conventional and pattern discrimination perimetry in a prospective study of glaucoma patients.

PURPOSE: To determine whether pattern discrimination perimetry detects progression of glaucomatous visual fields earlier than conventional static automated perimetry. METHODS: One hundred nine eyes of 109 patients with open angle glaucoma were enrolled in a longitudinal prospective study. Each patient underwent visual field examinations with conventional and pattern discrimination perimetry using the 30-2 program of the Humphrey Visual Field Analyzer (Humphrey Instruments Inc., San Leandro, CA) and a custom program for the pattern discrimination perimeter, respectively at 6-month intervals. Progression of glaucomatous visual field damage was assessed separately at each visit by predetermined criteria for conventional and pattern discrimination perimetry. The time to progression from baseline was calculated and the hemifield that showed progression first was documented for both conventional and pattern discrimination perimetry. RESULTS: Patients were followed for a mean of 5.1 years and a mean of 11.6 visits. Sixty-eight (62.3%) patients did not show progression with either technique. Of the remaining 41 patients, 15 (36.5%) showed progression with conventional perimetry alone, 9 (21.9%) with pattern discrimination perimetry alone, and 17 (41.4%) showed progression with both techniques. Of these 17 patients, 11 (64.7%) were detected earlier by conventional perimetry, and 6 (35.2%) were detected earlier by pattern discrimination perimetry. CONCLUSIONS: This study suggests that pattern discrimination perimetry is less effective than conventional perimetry in evaluating progressive glaucomatous visual field damage.

Adolescent↗
PubMed2000

Tumor patterning: analogies of neoplastic morphogenesis with embryogenesis.

Patterning or pattern formation is a spatial and temporal process, by which ordered arrangements of cells and tissue structure are attained. The term is mostly applied to the morphogenesis in developmental biology, but it can also be useful for the neomorphogenesis in tumor biology. Despite increasing data on the proliferation and differentiation of tumor cells, processes of tumor patterning are rarely studied and poorly understood. A fundamental embryonic process of patterning is the gastrulation and a basic example of neoplastic patterning is the colonic adenoma-carcinoma sequence. Both processes exhibit distinct nuclear translocations and expressions of beta-catenin, which is considered to be a decisive transcriptional regulator. Our recent studies demonstrate striking analogies of patterning and nuclear beta-catenin expressions between the colonic adenoma-carcinoma sequence and the gastrulation steps. The shared patterns are dissociation, reassembly, tubular reconstruction and branching of neoplastic cells in association with nuclear beta-catenin expressions. These new findings establish patterning as a relevant concept for tumor biology and link the neoplastic morphogenesis with embryogenesis.

Body Patterning↗
PubMed2001

Detailed field pattern is intrinsic to the embryonic mouse hippocampus early in neurogenesis.

There is accumulating evidence that the mammalian cerebral cortex is regionally specified early in neurogenesis. However, the degree and scale of the regional pattern that is intrinsic to different parts of the cortical primordium remains unclear. Here, we show that detailed patterning-the accurate positioning of several areas or fields-is intrinsic to the part of the primordium that generates the hippocampus. A caudomedial portion of the cortical primordium, the site from which the hippocampus arises, was isolated from potential extrinsic patterning cues by maintaining it in explant culture. Explants were prepared at embryonic day (E) 12.5, which is early in hippocampal neurogenesis in the mouse and 3 d before individual fields are seen by differential gene expression. Allowed to develop for 3 d in vitro, E12.5 explants upregulate field-specific patterns of gene expression with striking temporal and spatial accuracy. Possible sources of patterning signals intrinsic to the explants were evaluated by removing the cortical hem or presumptive extrahippocampal cortex from the explants. To expose cells to different local positional cues, explant fragments were grafted into ectopic positions in a larger explant. None of these manipulations altered the development of patterned, field-specific gene expression. Finally, explants harvested at E10.5 also upregulate field-specific gene expression, although less robustly. Some hippocampal patterning information is therefore intrinsic to the caudomedial cortical primordium at the time that the first hippocampal neurons are born at E10.5. By E12.5, hippocampal field patterning appears to be well established and resistant to the manipulation of several potential intrinsic cues.

Animals↗
PubMed2002

Spotting patterns on the fly.

Recognizing and anticipating change in industry patterns is a core competence for companies today, allowing managers to capitalize on opportunities before they are apparent to others. Yet despite the growing realization that recognizing patterns is important, companies are far from mastering how to do it, especially at the strategic level, where information is usually less profuse and much less precise. Pattern recognition is not a new skill, though, at least not to people outside the business world. Since antiquity, naturalists have relied on their ability to spot patterns to make sense of their surroundings. And surprisingly, there is much businesspeople can learn from bird-watching--as removed as it may seem from the fast-paced, bruising world of business--in terms of the cognitive demands pattern recognition requires. To learn more, HBR spoke with David Sibley, perhaps the nation's foremost birdwatcher and illustrator, and Julia Yoshida, a birder since 1965 and a physician at the Lahey Clinic in Burlington, Massachusetts. Sibley explains how expert birders draw on a wealth of tacit knowledge built up over the years to make identifications in a matter of seconds: "Once you've mastered common patterns, the real trick is to educate yourself about where discrepancies are most likely to appear--and to concentrate your attention on those areas." Although so fast as to be almost unconscious, the process he describes seems to be as methodical as one of Yoshida's medical diagnoses. "Recognizing a pattern involves knowing what to look for, what the possibilities are, and then sorting out those patterns when you are actually confronted with the patient," Yoshida says. "I don't think it's a eureka moment at all. It's a methodical process."

Administrative Personnel↗
PubMed2003

Antipsychotic medication use patterns and associated costs of care for individuals with schizophrenia.

BACKGROUND: Schizophrenia is a costly and complicated disorder to treat. A variety of schizophrenia treatment guidelines have been developed to provide valuable expert advice to practicing psychiatrists on various treatment options that are presumed to result in the best outcomes. However, examination of antipsychotic medication use patterns has suggested that current prescribing practices do not mirror recommended treatment guidelines and may have adverse economic consequences. AIM OF THE STUDY: This study seeks to describe antipsychotic medication treatment patterns and estimate the total costs of care associated with treatment patterns for individuals diagnosed with schizophrenia in usual care settings. METHODS: Use of outpatient antipsychotic medications and other health services during 1997 was obtained for 2,082 individuals with a diagnosis of schizophrenia in the IMS Health LifeLink employer claims database. We describe outpatient antipsychotic treatment patterns, estimated the costs of schizophrenia care by treatment pattern, and compared costs by treatment pattern using regression models. RESULTS: During 1997, 26% (n=536) of individuals diagnosed with schizophrenia received no antipsychotic medication in the outpatient setting, while 52% (n=1,088) were treated with only one antipsychotic (Monotherapy). For individuals who received more than one antipsychotic medication during 1997 (n=458), 13% (n=262) switched antipsychotic medications (Switch), 7% (n=154) augmented their original antipsychotic therapy with an additional antipsychotic (Augment), and 2% (n=42) of individuals were on more than one antipsychotic therapy at the start of the year. After adjusting for covariates, Switch and Augment patterns were associated with significant increases in total costs (an increase of 4,706 dollars (p<0.0001) and 4,244 dollars (p=0.0002), respectively) relative to Monotherapy. DISCUSSION: These results indicate that a substantial proportion of individuals with a diagnosis of schizophrenia were not treated with or had low exposure to antipsychotic therapy. Individuals treated with antipsychotic monotherapy experienced nearly half the annual costs as individuals who were treated with antipsychotic polytherapy or who switched antipsychotic medications. These observations should be interpreted in the context of the study limitations. IMPLICATIONS FOR HEALTH CARE PROVISION AND USE: This analysis indicates that there may be considerable room for improvement in the treatment for individuals diagnosed with schizophrenia. IMPLICATIONS FOR HEALTH POLICIES: Though schizophrenia affects a very small portion of the population, the individual and societal burden associated with the disorder is quite high. This paper suggests that antipsychotic monotherapy and continuous therapy, commonly recommended by published treatment guidelines, may be associated with economic savings. IMPLICATIONS FOR FURTHER RESEARCH: Future research should evaluate the impact of newer antipsychotic medications on patterns of care and economic outcomes. More information is also needed on which individual patient characteristics are likely to predict success or failure on specific treatments. Finally, more detailed information on the reasons or rationale for switching or augmenting original pharmacotherapy would be valuable in improving medication management in these complex and often difficult to treat patients.

Adult↗
PubMed1987

Persistence and extinction of the effect of visual pattern deprivation in the fly.

Visual pattern discrimination in the fly (Boettcherisca peregrina) is dependent on post-emergence experience of light and visual patterns (Mimura 1986). A behavioural study was made on the persistence of the functional modification that results from visual deprivation. When the fly was kept in the dark for 5 days post-emergence, the development of visual pattern discrimination was impaired completely, irrespective of the subsequent light condition, while photosensitivity was not impaired. A "deprivation" effect could also be produced by exposing the fly for at least 1 h soon after emergence to a definite pattern instead of its usual contrasted environment. Persistence of this deprivation effect depended on the subsequent light conditions: The effect was more persistent when the flies were kept in continuous darkness (DD) than when they were raised in light-dark (LD) environment; and The longer the presentation of a definite pattern, the more stable was the deprivation effect. Extinction of the deprivation effect was replaced with the development of normal pattern discrimination. In flies that had experienced a lighted, white, unpatterned environment after emergence, the normal development of pattern discrimination was impaired. This deprivation effect was persistently maintained when flies were kept in DD, but when flies were exposed to this environment for 5 h or more and then kept in LD, normal pattern discrimination developed gradually.

Animals↗
PubMed1998

Calculating the exact probability of language-like patterns in biomolecular sequences.

We present algorithms for the exact computation of the probability that a random string of a certain length matches a given regular expression. These algorithms can be used to determine statistical significance in a variety of pattern searches such as motif searches and gene-finding. This work improves upon work of Kleffe and Langebacker (Kleffe & Langbecker 1990) and of Sewell and Durbin (Sewell & Durbin 1995) in several ways. First, in many cases of interest, the algorithms presented here are faster. In addition, the type of pattern considered here strictly includes those of both previous works but also allows, for instance, arbitrary length gaps. Also, the type of probability model which can be used is more general than that of Sewell and Durbin, allowing for Markov chains. The problem solved in this work is in fact in the class of NP-hard problems which are believed to be intractable. However, the problem is fixed-parameter tractable, meaning that it is tractable for small patterns. The is problem is also computationally feasible for many patterns which occur in practice. As a sample application, we consider calculating the statistical significance of most of the PROSITE patterns as in Sewell and Durbin. Whereas their method was only fast enough to exactly compute the probabilities for sequences of length 13 larger than the pattern length, we calculate these probabilities for sequences of up to length 2000. In addition, we calculate most of these probabilities using a first order Markov chain. Most of the PROSITE patterns have high significance at length 2000 under both the i.i.d. and Markov chain models. For further applications, we demonstrate the calculation of the probability of a PROSITE pattern occurring on either strand of a random DNA sequence of up to 500 kilo-bases and the probability of a simple gene model occurring in a random sequence of up to 1 megabase.

Algorithms↗
PubMed2004

Significance of dermoscopic patterns in detecting malignant melanoma on acral volar skin: results of a multicenter study in Japan.

OBJECTIVE: To determine diagnostic variables such as sensitivity and specificity of the major dermoscopic patterns observed in melanocytic lesions on acral volar skin, with particular attention to the significance of the parallel ridge pattern and irregular diffuse pigmentation in detecting acral melanoma. DESIGN: Multicenter, retrospective study. SETTING: University hospitals in Japan. PATIENTS: Patients with melanocytic lesions on acral volar skin. A total of 712 melanocytic lesions (103 malignant melanomas, including 36 in situ lesions, and 609 melanocytic nevi) were consecutively collected from the files of 3 hospitals. Diagnoses of all the lesions had been determined histopathologically. INTERVENTIONS: Dermoscopic examination. MAIN OUTCOME MEASURES: The sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy of the major dermoscopic patterns seen in benign and malignant melanocytic lesions on acral volar skin. RESULTS: The parallel ridge pattern and irregular diffuse pigmentation showed extremely high specificity (99.0% and 96.6%, respectively) and very high negative predictive value (97.7% and 97.5%, respectively) in malignant melanoma. For melanoma in situ, the positive predictive value and diagnostic accuracy of the parallel ridge pattern were significantly higher than those of irregular diffuse pigmentation (P = .009 and P = .006, respectively). In melanocytic nevi, the specificity and positive predictive value of the parallel furrow pattern and/or the latticelike pattern were found to be very high (93.2% and 98.3%, respectively). CONCLUSIONS: Dermoscopy is immensely helpful in differentiating malignant melanomas from melanocytic nevi on acral volar skin. Moreover, the parallel ridge pattern aids in detecting acral melanomas in early, curable stages.

Adult↗
PubMedDate not supplied

Dietary patterns and the risk of coronary heart disease in women.

BACKGROUND: Although substantial information on individual nutrients or foods and risk of coronary heart disease (CHD) is available, little is known about the role of overall eating pattern. METHODS: Using dietary information from a food frequency questionnaire in 1984 from the Nurses' Health Study, we conducted factor analysis and identified 2 major dietary patterns-"prudent" and "Western"-and calculated factor scores of each pattern for individuals in the cohort. We used logistic regression to examine prospectively the associations between dietary patterns and CHD risk among 69 017 women aged 38 to 63 years in 1984 without history of major chronic diseases. RESULTS: The prudent pattern was characterized by higher intakes of fruits, vegetables, legumes, fish, poultry, and whole grains, while the Western pattern was characterized by higher intakes of red and processed meats, sweets and desserts, french fries, and refined grains. Between 1984 and 1996, we documented 821 CHD cases. After adjusting for coronary risk factors, the prudent diet score was associated with a relative risk (RR) of 0.76 (95% confidence interval (CI), 0.60-0.98; P for trend test,.03) comparing the highest with lowest quintile. Extreme quintile comparison yielded an RR of 1.46 (95% CI, 1.07-1.99; P for trend test,.02) for the Western pattern. Those who were jointly in the highest prudent diet quintile and lowest Western diet quintile had an RR of 0.64 (95% CI, 0.44-0.92) compared with those with the opposite pattern profile. CONCLUSION: A diet high in fruits, vegetables, whole grains, legumes, poultry, and fish and low in refined grains, potatoes, and red and processed meats may lower risk of CHD.

Adult↗
PubMed1986

Simultaneous recording of pattern electroretinography and visual evoked potentials in multiple sclerosis. A method to separate demyelination from axonal damage to the optic nerve.

Pattern electroretinograms (P-ERGs) and visual evoked potentials (VEPs) were recorded in 35 patients with multiple sclerosis and in 35 age-matched normal subjects. Four patterns of abnormalities were noted in the group with multiple sclerosis. The most frequent abnormality consisted of the following: normal P-ERG, delayed P100, and prolonged interpeak interval between the b-wave of the P-ERG and P100 (retinocortical time). This pattern indicates demyelination of the optic nerve. A second pattern consisted of absent P-ERG and absent VEP. This pattern was associated with optic atrophy and/or central scotoma, indicating severe optic nerve axonopathy with retrograde degeneration of ganglion cells. A third pattern consisted of normal P-ERG and absent VEP, suggesting a total block of transmission at the optic nerve. A fourth pattern consisted of present but low-amplitude P-ERG, delayed VEP, and prolonged retinocortical time, indicating a demyelinating process with partial axonal involvement. The concomitant use of P-ERG and VEP results in a better classification of the type and severity of dysfunction affecting the optic nerve. The prognostic value of the four patterns for recovery of visual function is discussed.

Electroretinography↗
PubMed2005

Spectrum of pattern dystrophy in pseudoxanthoma elasticum.

OBJECTIVE: To study the prevalence, type, and features of pattern dystrophy in patients with pseudoxanthoma elasticum (PXE). METHODS: A search of the photographic records at the Vanderbilt Eye Institute using the keywords "angioid streaks and pseudoxanthoma elasticum" yielded 28 names. Of the 23 subjects meeting the patient selection criteria, 22 were confirmed to have a positive diagnosis for PXE after reviewing the medical history information. The diagnosis was confirmed by the constellation of fundus findings in all 22 subjects, by a clinical examination of the skin in 9, and by a skin biopsy specimen in 1. RESULTS: Pattern dystrophy was present in 16 patients (27 eyes) of those with PXE. Fourteen patients (23 eyes) had fundus pulverulentus, 3 patients (5 eyes) had butterfly-shaped dystrophy, and 1 patient (2 eyes) each had fundus flavimaculatus and reticular dystrophy. One eye of one patient developed solitary vitelliform pattern dystrophy during follow-up. Two patients showed progression from one pattern into another during follow-up. Another patient, who at first showed no evidence of pattern dystrophy in either eye, developed fundus pulverulentus in both eyes 5 years later. One patient had simultaneous evidence of 2 types: butterfly and fundus flavimaculatus pattern in each eye. Angioid streaks were seen in each eye of all patients. Peau d'orange was noted in 18 patients, optic nerve drusen in 5, and retinal crystalline bodies in 9. Choroidal neovascular membrane was present in 15 patients. CONCLUSIONS: All 5 varieties of pattern dystrophy, 2 of which were not previously associated with PXE, were seen in patients with PXE. Fluorescein angiogram was useful in delineating the type and extent of pattern dystrophy.

Adult↗
PubMed2000

Physiological patterns in the hippocampo-entorhinal cortex system.

The anatomical connectivity and intrinsic properties of entorhinal cortical neurons give rise to ordered patterns of ensemble activity. How entorhinal ensembles form, interact, and accomplish emergent processes such as memory formation is not well-understood. We lack sufficient understanding of how neuronal ensembles in general can function transiently and distinctively from other neuronal ensembles. Ensemble interactions are bound, foremost, by anatomical connectivity and temporal constraints on neuronal discharge. We present an overview of the structure of neuronal interactions within the entorhinal cortex and the rest of the hippocampal formation. We wish to highlight two principle features of entorhinal-hippocampal interactions. First, large numbers of entorhinal neurons are organized into at least two distinct high-frequency population patterns: gamma (40-100 Hz) frequency volleys and ripple (140-200 Hz) frequency volleys. These patterns occur coincident with other well-defined electrophysiological patterns. Gamma frequency volleys are modulated by the theta cycle. Ripple frequency volleys occur on each sharp wave event. Second, these patterns occur dominantly in specific layers of the entorhinal cortex. Theta/gamma frequency volleys are the principle pattern observed in layers I-III, in the neurons that receive cortical inputs and project to the hippocampus. Ripple frequency volleys are the principle population pattern observed in layers V-VI, in the neurons that receive hippocampal output and project primarily to the neocortex. Further, we will highlight how these ensemble patterns organize interactions within distributed forebrain structures and support memory formation.

Afferent Pathways↗
PubMed1991

Spatial and temporal patterns of muscle cleavage in the chick thigh and their value as criteria for homology.

Regions of lower cell density, called cleavage zones, emerge within the dorsal and ventral muscle masses in the vertebrate limb to separate distinct muscles. In the chick thigh, the stereotyped patterns of separation have been broadly outlined, but differences in interpretation exist because no criteria for separation have been defined, and the tissues of the limb are indistinct early in development. We have examined the cleavage process using modern applications of light microscopy and immunocytochemistry to completely detail the spatial and temporal progression of cleavage in stage 27-32 embryos. We find that each muscle has a complex but characteristic pattern of separation along the proximodistal axis. The complex pattern of separation is not related to the positions of muscles within the thigh, locations of blood vessels, activity patterns of muscles, or innervation patterns. The initial separation patterns are more straightforward than later separations and may be of value in determining the phylogenetic history of limb muscles since the same patterns are common to many tetrapods. Our detailed documentation clarifies the ontogeny of the thigh musculature and reveals more complex separation patterns between muscles than previously described.

Animals↗
PubMed1994

Embryonic expression patterns of the Drosophila decapentaplegic gene: separate regulatory elements control blastoderm expression and lateral ectodermal expression.

Patterns of decapentaplegic (dpp) transcripts derived from the intact gene were compared to the patterns of transcripts generated by partial dpp transgenes in Drosophila embryos. Sequences closest to the dpp coding regions, the dpp hin region, were sufficient to express lacZ-tagged mRNA in patterns indistinguishable from the patterns of endogenous dpp expression in the dorsal and terminal cells at the blastoderm stage, in the dorsal ectoderm during germ band elongation, and in narrow stripes of ectodermal cells along the dorsal edge of the ectoderm and at the boundary between the lateral and ventral neurogenic regions during germ band shortening. The latter pattern of expression responded to the segment polarity genes naked and wingless. However, these dpp sequences were not sufficient to drive lacZ-tagged mRNA expression in other cells normally expressing dpp, including cells in the gnathal segments, the clypeolabrum, the foregut, the midgut visceral mesoderm, and the hindgut. Two separate regulatory regions were found in the dpp hin region. A 479 bp region upstream of the promoter was necessary for the segmented pattern of expression in the lateral ectoderm and for expression in the midgut endoderm. Cis-acting elements in the 2 kbp second intron directed expression in the dorsal and terminal regions of the blastoderm, acted on a heterologous promoter, the P-element promoter, and responded to pattern information derived from the maternal effect dorsal/ventral patterning genes.

Animals↗
PubMed2005

Anatomical variations of the cutaneous innervation patterns of the sural nerve on the dorsum of the foot.

The present study attempts to determine the cutaneous pattern of distribution of the sural nerve on the dorsum of the foot to note the predominant pattern present and whether there was any association between the innervation pattern and sex or side. A total of 260 Indian feet (78 adult feet: 60 male, 18 female; 52 fetal feet: 20 male, 32 female) were dissected. The results showed six patterns of innervation of the toes by the sural nerve. In Type I, the lateral side of the little toe was supplied by the sural nerve alone and the adjacent sides of the 2nd, 3rd, 4th, and 5th toes by the superficial peroneal nerve alone (35.38%). In Type II the lateral side of the little toe was supplied by the sural nerve alone and the adjacent sides of the 4th and 5th toes by the sural nerve along with the superficial peroneal nerve (10%). In Type III the lateral side of the little toe was supplied by the sural nerve alone and the adjacent sides of the 3rd, 4th, and 5th toes by the sural nerve along with the superficial peroneal nerve (21.15%). In Type IV the lateral 1(1/2) toes were supplied by the sural nerve alone and the adjacent sides of the 3rd and 4th toes by the superficial peroneal nerve alone (3.85%). In Type V the lateral 1(1/2) toes were supplied by the sural nerve alone and the adjacent sides of the 3rd and 4th toes were supplied by the sural nerve along with the superficial peroneal nerve (5%). In Type VI the lateral 2(1/2) toes were supplied by the sural nerve alone (24.61%). The predominant patterns were Type I (35.38%), Type VI (24.61%), and Type III (21.15%). There was no association between the innervation pattern of the sural nerve and sex or side. The pattern, which is usually described, was found in only 35.38% of feet. Considering the variation in the pattern of cutaneous distribution of the sural nerve in Indian feet, the function of the sural nerve may be to supply a wider area of skin than is usually described.

Adult↗
PubMed2002

Detection of underlying characteristics of nuclear chromatin patterns of thyroid tumor cells using texture and factor analyses.

BACKGROUND: Aspiration biopsy cytology of thyroid tumors has been used more frequently in recent times to differentiate between malignant and benign lesions. Chromatin patterns of the tumor cell nuclei are one of most important factors for cytologic diagnosis. The interpretation of nuclear chromatin patterns is subjective and more difficult than that of nuclear size or shape. In the present report, we investigated how to detect underlying chromatin characteristics of benign and malignant thyroid tumor cells by means of texture and factor analyses. METHODS: We employed a computer-aided system in which light microscopy was combined with an image processor and monochrome camera. Using this system, 100 randomly selected cells in a Papanicolaou stained, aspiration biopsy cytologic smear in each case of 39 benign and malignant thyroid tumor cases were digitized. We applied two-dimensional and higher texture analyses with the use of co-occurrence and run-length matrices to analyze the chromatin patterns. Factor analysis was used to determine whether a large number of independent variables actually measured one or more underlying common variables. RESULTS: According to parameters with high factor-loading values, the morphologic chromatin characters were classified into three categories according to heterogeneity, contrast, and homogeneity of chromatin patterns. On the basis of analyses with these morphologic categories, nuclei of papillary carcinoma showed higher contrast of chromatin patterns than did those of the benign group. Moreover, there was a variety of contrasting chromatin patterns among cells in each papillary carcinoma case in comparison with the benign group. In contrast, follicular carcinomas showed a significant difference in the standard deviation of factor 3, which indicated more monotonous chromatin patterns among cells in each follicular carcinoma case than in each benign case. CONCLUSION: We believe that this technique, using texture and factor analyses, is useful in the detection of underlying characteristics of nuclear chromatin patterns in aspiration biopsy cytology.

Adenocarcinoma, Follicular↗
PubMed2006

Patterning of coronary arteries in wildtype and connexin43 knockout mice.

Abnormal patterning of coronary arteries (CAs) is a clinically significant problem, and as yet, few animal models have been systematically investigated for coronary patterning defects. Here we characterized coronary artery (CA) insertion and branching patterns of the proximal coronary stems in the hearts of wildtype and heterozygous connexin43 knockout (Cx43alpha1 KO) mice. This study entailed the use of high-resolution micro CT imaging for three-dimensional coronary reconstructions. MicroCT of 17 wildtype mice showed a remarkably consistent pattern of CA deployment in the normal mouse heart. Two main CA stems are inserted from the left and right into the aorta. The right coronary artery then branches immediately into the right main and the septal-conal branch, while the left coronary artery branches further distally into the circumflex and the anterior descending CA. This patterning of CA anatomy was confirmed by histology, and by using a vascular smooth muscle or endothelial cell specific lacZ reporter gene to delineate the CAs. A parallel analysis of 25 heterozygous Cx43alpha1 KO mouse hearts showed 22 had defects in patterning of the CAs. They exhibited a wide variation in CA anatomy, including abnormal origin and course of the main CA stems, multiple accessories, and dual septal-conal branches. Overall, these studies show loss of one Cx43alpha1 allele (haploinsufficiency) leads to a high incidence of coronary patterning defects. These findings suggest CA patterning is sensitive to Cx43alpha1 gene dosage.

Animals↗