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Differences in automated depolarization patterns of Plasmodium falciparum and P. vivax malaria infections defined by the Cell-Dyn CD4000 haematology analyser.

Of 1014 samples submitted for full blood count analysis and malaria screening, 854 were designated malaria-negative by blood film microscopy, 79 were unequivocally identified as Plasmodium vivax and 81 as P. falciparum. All samples were additionally analysed with the Abbott Cell-Dyn CD4000 haematology instrument, and leucocyte differential plots of 90 degrees polarized vs. 90 degrees depolarized (NEU-EOS plot) and 90 degrees depolarized vs. 0 degree light (EOS I plot) scatter were specifically examined for abnormal depolarization patterns. Depolarization pattern types were correlated with microscopy (species) results, and these correlations were consolidated by polymerase chain reaction analysis. All 854 microscopically-designated malaria-negative samples showed a type 1 (normal) CD4000 depolarization pattern. Abnormal pattern types 2, 3a and 3b were entirely restricted to one of the two malaria categories. Plasmodium falciparum malaria showed two CD4000 pattern types only; a 'normal' type 1 pattern was seen in 36/75 (48%) cases and the remaining 39 cases were all abnormal pattern type 3a. In contrast, most (79/85) P. vivax malaria cases showed a distinctive clustered EOS I population (types 2 and 3b patterns) that was not seen with P. falciparum. Automated depolarization analysis provides an effective means of detecting malaria-associated haemozoin, and the patterns of intracellular haemozoin further appear to provide species differentiation between P. falciparum and P. vivax.

Animals↗

Occurrence and patterns of muramidase containing cells in Hodgkin's disease, non-Hodgkin's lymphomas, and reactive hyperplasia.

The occurrence and pattern of cytoplasmic muramidase containing histiocytes were studied by the unlabeled antibody peroxidase-antiperoxidase method in biopsy material from patients with Hodgkin's disease, non-Hodgkin's lymphomas, and reactive hyperplasia. The majority of lymph nodes from patients with Hodgkin's disease, nodular lymphoma, and reactive hyperplasia gave positive staining reactions when tested in this manner. Differences in the staining pattern were observed for the different conditions studied. In general, stain positive cells occurred in one of the following four patterns: nodular, dispersed, aggregating without background stain, or aggregating with background stain (mottling pattern). The nodular and aggregating without background stain patterns were not specific and were seen in various conditions. The dispersed pattern, however, was observed only in some cases of non-Hodgkin's diffuse lymphomas, suggesting a subgroup of tumors characterized by active participation of reactive histiocytes. The mottling pattern was virtually limited to Hodgkin's disease. Since the mottling pattern appeared to be produced by virtue of a large amount of extracellular muramidase, the elevation of the serum muramidase level in Hodgkin's disease may be related to enzymatically active secretory histiocytes. Moreover, the mottling staining pattern was observed frequently in the lymphocytic predominance and nodular sclerosis type of Hodgkin's disease, but relatively infrequently in the mixed cellularity or lymphocytic depletion types, suggesting that the variation in histiocytic activity may be related to the course of the disease. The decreased staining reaction observed in the latter two categories could not be accounted for by a decrease in the numbers of histiocytic cells in hematoxylin and eosin stained sections, suggesting that release or synthesis may be defective in those unfavorable types of Hodgkin's disease.

Cytoplasm↗

Electrophysiological recordings of patterned rat brain stem slice neurons.

Dissociated neuronal cultures on substrates patterned with extracellular matrix (ECM) proteins have yielded much information in the past. However, although the culture of brain slices has many advantages over dissociated neuronal cultures, its feasibility on patterned substrates has not been demonstrated to date. In the present study, neuronal outgrowth from brain stem slices onto homogeneous control substrates, and onto laminin structures of grid- and line-shape was achieved. Cultures were evaluated by means of phase contrast microscopy, antibody staining, and patch-clamp measurements. Only patterns with line sizes of more than 4 microm yielded satisfactory neuronal outgrowth. The size of the nodes in the pattern influenced the nodal compliance of the spreading cells and the amount of unstructured overgrowth. Best grid patterns were 4 microm lines and 10 microm nodes, best line patterns were 4 microm lines and 20 microm nodes. On patterned substrates, average sodium and potassium currents were reduced by approximately 50% compared to controls, whereas area-normalized ion-currents were in the same order of magnitude. This indicates that as a consequence of the pattern-enforced geometrical confinement, neurons tend to have a smaller surface. In addition, neurons on patterned substrates were rapidly covered with glial overgrowth. This was shown by antibody staining.

Animals↗

Statistical evaluation of clusters derived by nonlinear mapping of EEG spatial patterns.

New methods were devised to improve the discrimination of EEG spatial amplitude patterns recorded from arrays of 64 electrodes placed on visual, auditory or somatic cortex. The 64 traces shared a spatially coherent, aperiodic carrier wave with a spatial pattern of amplitude modulation (AM). Previous observations on AM patterns from rabbits trained to discriminate conditioned stimuli with reinforcement (CS+) and without (CS-) had revealed epochs between the CS and the CR in which AM patterns on CS+ trials could be distinguished from AM patterns on CS- trials. The AM patterns were expressed by points in 64-space that formed clusters. Levels of CS-/CS+ pattern separation were quantified by a pair-wise Euclidean distance method with cross-validation. The present study documents use of the technique for nonlinear mapping (NLM) to project the 64-dimensional structure onto a plane while preserving the relative distances between all points. The goodness of classification by the Euclidean distance measure was the same or improved after projection. Whereas the Euclidean distance measure only gave pair-wise classifications, the planar displays showed the patterns for multiple clusters simultaneously. These NLM-based methods revealed previously unrecognized structures within distributions of AM patterns in sensory cortices in the time period between the CS and CR.

Animals↗

Effects of elevated serotonin levels on patterns of GAP-43 expression during barrel development in rat somatosensory cortex.

Elevating cortical serotonin (5-HT) in rats with clorgyline, a monoamine oxidase A (MAO(A)) inhibitor, from postnatal day (P-0) to P-6 delays the organization of thalamocortical afferent fibers into a vibrissae-related pattern in the somatosensory cortex (S-I). Despite continued elevation of cortical 5-HT through P-8, the thalamocortical fibers do form, albeit with some delay, a characteristic vibrissae pattern of barrels in layer IV of S-I by P-8. The growth-associated protein, GAP-43, is transiently expressed in developing S-I cortex of normal rats in a vibrissae related pattern until P-7. After P-7, GAP-43 expression is reduced in the barrel centers and increased in the septa. The present study evaluated the effect of elevated 5-HT levels on the distribution of GAP-43 immunoreactivity in S-I. We employed 5-HT immunocytochemistry and 1,1'-dioctadecyl-3,3,3",3'-tetramethylindocarbocyanine perchlorate (DiI) labeling of thalamic radiations to confirm a 'barrelless' phenotype in P-6 clorgyline-treated animals and a recovered barrel pattern in treated animals allowed to survive until P-8 and P-10. GAP-43 immunocytochemistry was used to evaluate the cortical distribution of this protein in similarly treated littermates. Continuous inhibition of MAO(A) from P-0 to P-6 resulted in a corresponding loss of the GAP-43 vibrissae-related pattern at P-6. Despite continued elevation of cortical 5-HT until P-8 and P-10, the characteristic vibrissae-complementary pattern of GAP-43 emerged with expression concentrated in the septa and rows. GAP-43 vibrissae-related thalamocortical axon pattern never appeared in the clorgyline-treated animals. Thus, while elevated 5-HT delays development of a vibrissae-related pattern of thalamocortical afferents, it does not appear to alter the time when a GAP-43 vibrissae-related complementary pattern emerges.

Animals↗

Shared dynamics of attentional cost and pattern stability.

This paper examines the informational activity devoted by the CNS to couple oscillating limbs in order to sustain and stabilize bimanual coordination patterns. Through a double-task paradigm associating a bimanual coordination task and a reaction time (RT) task, we investigated the relation between the stability of preferred bimanual coordination patterns and the central cost expended by the CNS for their stabilization. Ten participants performed in-phase and anti-phase coordination patterns in a dual task condition (coordination + RT) at several frequencies (0.5, 0.75, 1.0, 1.5, and 2.0 Hz), thereby decreasing the stability of the bimanual patterns. Results showed a U-shaped evolution of pattern stability and attentional cost, as a function of oscillation frequency, exhibiting a minimum value at the same frequency. These findings indicate that central cost and pattern stability covary and may share common, high order dynamics. Moreover, the attentional focus given to the bimanual coordination and the RT task was also manipulated by requiring either shared attention or priority to the coordination task. Such a manipulation led to a tradeoff between pattern stability and RT performance: The more stable the pattern, the more costly it is to stabilize. This suggests that stabilizing a coordination pattern incurs a central cost that depends on its intrinsic stability. Conceptual consequences of these results for understanding the relationship between attention and coordination are drawn, and the mechanisms putatively at work in dual tasks are discussed.

Adult↗

Asymmetric interference in patterning discriminations: a case of modulated attention.

In sequential training positive patterning hinders negative patterning, but not vice versa. This asymmetry was attributed to interference of two different rules. In a Pavlovian skin conductance response conditioning experiment with humans, we further investigated this effect. Two groups performed sequential training of positive and negative patterning with a reduced number of trials per training schedule. In Group PNP, the sequence was positive patterning (A-, B-, AB+), negative patterning (C+, D+, CD-), followed by positive patterning (E-, F-, EF+). Group NPN consisted of negative patterning (A+, B+, AB-), positive patterning (C-, D-, CD+), and negative patterning (E+, F+, EF-) again. As predicted by an attentional explanation we found no interference. Hence, the asymmetry observed earlier had been due to less attention to specific stimuli in consequence of an extensive use of the numerosity-rule.

Adolescent↗

V-blender segregation patterns for free-flowing materials: effects of blender capacity and fill level.

Stable segregation patterns are shown to form in V-blenders over a wide range of vessel capacities, fill levels, and rotation rates. Slight changes in either rotation rate or fill level induce changes in pattern formation. Trajectory segregation in two regions of the flow, accumulating over many flow periods, drives segregation pattern formation. Scaling criteria derived to relate particle velocities to vessel size and rotation rate in rotating cylinders successfully predict the rotation rate for the transition between patterns across V-blenders of 0.8-26.5 quart total capacity. This agreement suggests that pattern formation is governed by the magnitude of particle velocities. Regardless of vessel size, when particle velocities at specific regions of the blender are below a certain value, one particular pattern appears, and when they increase beyond that speed (i.e. by changing the rotation rate or the vessel size), a different pattern emerges. A scaling relation between segregation pattern formation and blender fill level was not identified because the complex flow patterns in the V-blender (the length of the flowing layer and the mixture center of mass relative to the blender are constantly oscillating) preclude the determination of a relationship between blender fill level and particle velocities.

Chemical Phenomena↗

Generalized spike-and-wave patterns in children: clinical correlates.

All electroencephalograms performed in our institution between 1980 and 1990 were reviewed. The clinical characteristics of children with epilepsy and generalized spike-and-wave (SW) patterns were analyzed. The SW patterns were classified according to their frequency. Electroencephalograms of 154 children with epilepsy revealed SW patterns. Absence seizures were the most common first seizure, but partial seizures were frequent. More than 40% had several types of seizures. Sixty percent of the epileptic syndromes were generalized, but almost 25% were partial. The typical SW pattern was associated with absence seizures, a normal examination and computed tomographic scan, idiopathic generalized epilepsies, monotherapy, freedom from seizures, and lack of recurrence. The slow SW pattern was associated with West syndrome; a younger age at seizure onset; atonic, myoclonic, tonic, and partial simple seizures; an abnormal examination and computed tomographic scan; cryptogenic or symptomatic generalized epilepsy or symptomatic partial epilepsy; polytherapy; and poor seizure control. The fast SW pattern was associated with secondary generalized, partial, tonic-clonic, and complex partial seizures; a normal computed tomographic scan; cryptogenic partial epilepsy; isolated seizures; and seizure recurrence. Epilepsy with a typical SW pattern should be considered benign, epilepsy with a slow SW pattern malignant, and epilepsy with a fast SW pattern treacherous.

Adolescent↗

Encoded pattern classification using constructive learning algorithms based on learning vector quantization.

A novel encoding technique is proposed for the recognition of patterns using four different techniques for training artificial neural networks (ANNs) of the Kohonen type. Each template or model pattern is overlaid on a radial grid of appropriate size, and converted to a two-dimensional feature array which then acts as the training input to the ANN. The first technique employs Kohonen's self-organizing network, each neuron of which is assigned, after training, the label of the model pattern. It is found that a graphical plot of the labels of the neurons exhibits clusters (which means in effect that the feature array pertaining to distorted versions of the same pattern belongs to a specific cluster), thereby justifying the coding strategy used in this paper. When the new, unknown pattern is input to the network, it is classified to have the same label of the neuron whose corresponding model pattern is closest to the given pattern. In an attempt to reduce the computational time and the size of the network, and simultaneously improve accuracy in recognition, Kohonen's learning vector quantization (LVQ) algorithm is used to train the ANN. To further improve the network's performance and to realize a network of minimum size, two constructive learning algorithms, both based on LVQ, are proposed: (1) multi-step learning vector quantization (MLVQ), and (2) thermal multi-step learning vector quantization (TLVQ). When the proposed algorithms are applied to the classification of noiseless and noisy (and distorted) patterns, the results demonstrate that the pattern encoding strategy and the suggested training techniques for ANNs are efficient and robust. For lack of space, only the most essential results are presented here. For details, see Ganesh Murthy and Venkatesh (1996b).

Journal Article↗

Comparison of screw placement patterns on the rigidity of the sagittal split ramus osteotomy: technical note.

Various screw placement patterns have been described for fixation of the sagittal split ramus osteotomy. This study is a comparative evaluation of 3 different screw placement patterns on the rigidity of the sagittal split ramus osteotomy. Twenty cadaver mandibles were used to compare the load strength of triangular pattern, oblique linear pattern versus linear pattern. Internal fixation with screws placed in a triangular pattern were significantly more rigid than those fixed with screws placed in the other patterns. Also, internal fixation with an oblique linear pattern was more rigid than that with a linear pattern.

Bone Screws↗

Characterization of Neisseria meningitidis isolated by ribosomal RNA gene restriction patterns and restriction endonuclease digestion of chromosomal DNA.

The use of ribosomal RNA (rRNA) gene restriction patterns to study the molecular epidemiology of Neisseria meningitidis was investigated. Ninety-four isolates of Neisseria meningitidis were characterized by their rRNA gene restriction patterns with 16 + 23 S rRNA from Escherichia coli as a probe. Thirteen rRNA gene restriction patterns were recognized; each of these patterns represented between 1 and 30 isolates. Isolated with the outbreak-associated phenotype B15P1.16 (sulphonamide resistant) all gave a single rRNA gene restriction pattern but this pattern also contained isolates with other phenotypes. Further discrimination between isolates was achieved by comparison of banding patterns resulting from restriction endonuclease digestion of chromosomal DNA with Bgl II. This gave a banding pattern consisting of about ten bands which was simple to interpret. Using this technique 94 isolates were classified in 54 patterns containing between 1 and 14 isolates. Restriction endonuclease analysis with Bgl II characterized outbreak-associated isolates with the phenotype B15P1.16 and enabled strains not typable by conventional methods to be identified as probable outbreak-associated isolates. The techniques should prove useful for epidemiological studies.

Bacterial Proteins↗

Directed immobilization of protein-coated nanospheres to nanometer-scale patterns fabricated by electron beam lithography of poly(ethylene glycol) self-assembled monolayers.

Controlling the spatial organization of biomolecules on solid supports with high resolution is important for a wide range of scientific and technological problems. Here we report a study of electron beam lithography (EBL) patterning of a self-assembled monolayer (SAM) of the amide-containing poly(ethylene glycol) (PEG) thiol CH(3)O(CH(2)CH(2)O)(17)NHCO(CH(2))(2)SH on Au and demonstrate the patterning of biomolecular features with dimensions approaching 40 nm. The electron dose dependence of feature size and pattern resolution is studied in detail by atomic force microscopy (AFM), which reveals two distinct patterning mechanisms. At low doses, the pattern formation occurs by SAM ablation in a self-developing process where the feature size is directly dose-dependent. At higher doses, electron beam-induced deposition of material, so-called contamination writing, is seen in the ablated areas of the SAM. The balance between these two mechanisms is shown to depend on the geometry of the pattern. The patterned SAMs were backfilled with fluorescent 40-nm spheres coated with NeutrAvidin. These protein-coated spheres adhered to exposed areas in the SAM with high selectivity. This direct writing approach for patterning bioactive surfaces is a fast and efficient way to produce patterns with a resolution approaching that of single proteins.

Adhesiveness↗

Effect of left atrial-coronary sinus musculature connections on the coronary sinus activation pattern via retrograde conduction in patients with WPW syndrome.

BACKGROUND: Double potential (DP) activation patterns observed in coronary sinus (CS) electrograms recorded during left lateral atrial pacing, were explained by an initial low-frequency left atrial (LA) activation potential and secondary high-frequency CS musculature activation potential in canine hearts. Moreover, the connections between the LA and CS musculature vary greatly in size and location in the human heart. The purpose of this study was to investigate the relationship between the CS activation pattern during retrograde conduction via an accessory pathway (AP) and the location of left-sided APs. METHODS AND RESULTS: Fifty-one patients (31 males, mean age 48.6 years) who underwent radiofrequency catheter ablation of left-sided APs were divided into two groups according to the successful ablation site. The CS electrograms during retrograde AP conduction were classified into 3 types; single, fractionated, and DP activation patterns. A DP pattern was identified in 10 of 12 patients (83.3%) with posteroseptal to posterolateral APs, and in particular, 9 had a divergent sequence. Twenty-six of 39 patients (66.7%) with lateral to anterolateral APs, demonstrated a single pattern. The number of radiofrequency applications was significantly higher in patients with a DP pattern than in those with a single pattern (3.4 +/- 3.3 vs. 7.8 +/- 6.8, p < 0.01). CONCLUSION: Misleading information obtained when mapping for optimal ablation sites might result from DP patterns with a divergent sequence produced by discrete muscular connections between the LA and CS musculature. Ablation around left posterior APs may require meticulous observation of the CS activation patterns.

Action Potentials↗

Dietary patterns and the metabolic syndrome in obese and non-obese Framingham women.

OBJECTIVES: To examine the relationship between habitual dietary patterns and the metabolic syndrome (MetS) in women and to identify foci for preventive nutrition interventions. RESEARCH METHODS AND PROCEDURES: Dietary patterns, nutrient intake, cardiovascular disease (CVD), and MetS risk factors were characterized in 1615 Framingham Offspring-Spouse Study (FOS) women. Dietary pattern subgroups were compared for MetS prevalence and CVD risk factor status using logistic regression and analysis of covariance. Analyses were performed overall in women and stratified on obesity status; multivariate models controlled for age, apolipoprotein E (APOE) genotypes, and CVD risk factors. RESULTS: Food and nutrient profiles and overall nutritional risk of five non-overlapping habitual dietary patterns of women were identified including Heart Healthier, Lighter Eating, Wine and Moderate Eating, Higher Fat, and Empty Calories. Rates of hypertension and low high-density lipoprotein levels were high in non-obese women, but individual MetS risk factor levels were substantially increased in obese women. Overall MetS risk varied by dietary pattern and obesity status, independently of APOE and CVD risk factors. Compared with obese or non-obese women and women overall with other dietary patterns, MetS was highest in those with the Empty Calorie pattern (contrast p value: p<0.05). DISCUSSION: This research shows the independent relationship between habitual dietary patterns and MetS risk in FOS women and the influence of obesity status. High overall MetS risk and the varying prevalence of individual MetS risk factors in female subgroups emphasize the importance of preventive nutrition interventions and suggest potential benefits of targeted behavior change in both obese and non-obese women by dietary pattern.

Abdomen↗

Water and food consumption patterns of U.S. adults from 1999 to 2001.

OBJECTIVE: High water consumption has been proposed as an aid to weight control and as a means of reducing the energy density of the diet. This study examines the relationship between water consumption and other drinking and eating patterns. RESEARCH METHODS AND PROCEDURES: The National Health and Nutrition Examination Survey 1999 to 2001, with responses from 4755 individuals > or =18 years of age, provides the data for this cross-sectional analysis. A cluster analysis was performed using z-scores of specific food and beverage consumption to examine patterns. A multinomial logit analysis was used to examine sociodemographic characteristics of each dietary pattern and to examine the effects of water consumption on the likelihood of consuming a non-dairy caloric beverage. All results were weighted to be nationally representative and controlled for design effects. RESULTS: Within the sample, 87% consumed water, with an average daily consumption of 51.9 oz (1.53 liters) per consumer. Water consumers drank fewer soft/fruit drinks and consumed 194 fewer calories per day. Water consumers (potentially a self-selected sample) consumed more fruits, vegetables, and low- and medium-fat dairy products. Four distinct unhealthy dietary patterns were found that included little or no water consumption. Older and more educated persons used healthier food patterns. Mexican dietary patterns were much healthier than dietary patterns of blacks. DISCUSSION: Water consumption potentially is a dietary component to be promoted, but much more must be understood about its role in a healthy diet. Because high water consumption is linked with healthier eating patterns-patterns more likely to be followed by higher-educated, older adults-the target of water promotion and healthy diet options should focus on younger and less educated adults.

Adult↗

Food intake patterns and risk of coronary heart disease: a prospective cohort study examining the use of traditional scoring techniques.

OBJECTIVE: This study analyses the risk of coronary heart disease (CHD) associated with food intake patterns. DESIGN: A cohort study with follow-up in 1996 for first admission to hospital for a CHD diagnosis or death caused by CHD (280 cases). Three food patterns were identified from a food frequency questionnaire: (1) a predefined healthy food index; (2) a prudent diet (reflecting frequent intakes of wholemeal cereals, fruit and vegetables); and (3) a Western food pattern (reflecting frequent intakes of meat products, butter and white bread) derived by factor analysis. Both factor scores had a mean of zero and a standard deviation of 1. SETTING: Copenhagen County, Denmark. SUBJECTS: A random sample of 7316 adults participated in health examinations conducted either in 1982-1984, 1987, or 1991-1992. RESULTS: The healthy food index and the Western pattern were not associated with CHD. The prudent pattern was associated with a decreased risk of CHD (Hazard ratio (HR per score unit increase)=0.85; 95% confidence intervals (CI), 0.75, 0.96), but the association vanished (HR=1.06; 95% CI, 0.93, 1.21) after controlling for confounding. Body mass index (BMI) modified the effect of the prudent and the Western patterns on CHD risk, suggesting an inverse association between both patterns and CHD in persons with low BMI, while the risk of CHD seemed to be positively related to the prudent and the Western pattern in those with high BMIs. CONCLUSIONS: This study showed no association between dietary patterns and CHD risk, but suggests that BMI modifies the relation between diet and CHD risk.

Adult↗

Ambulatory systolic blood pressure patterns in elderly hypertensives.

In a recent study we found that patients with isolated systolic hypertension (ISH) had two patterns of systolic blood pressure (SBP) elevations by ambulatory BP monitoring (ABPM), sustained (S) and intermittent (I), the prognostic significance of which seems to be different. In the present study we tried to determine whether such patterns of SBP elevations may be detected among other hypertensives as well. Twenty-eight elderly patients (mean age 65.5+/-5.1 years), nine with ISH, 10 with systolodiastolic hypertension (SDH), and nine with white coat hypertension (WCH), underwent ABPM. Average clinic BP in the ISH group was 184/83 mm Hg, in the SDH group 172/101 mm Hg, and in the WCH group 166/91 mm Hg, where as the ABPM averages were 169/80, 167/95 and 132/73 mm Hg, respectively, and differences held true for both daytime and night-time. Five ISH and four SDH patients had S patterns on ABPM, while the other four ISH and six SDH patients exhibited I patterns; none of the nine WCH subjects had either S or I patterns. ECG revealed left ventricular hypertropy (LVH) and/or ischaemic changes in eight patients with S patterns (ISH and SDH groups combined), as opposed to two patients with I patterns and only one patient of the WCH group. This seems to further suggest that an S pattern of SBP elevation on ABPM may have worse prognostic implications than either an I pattern or no SBP elevation.

Aged↗