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At least 163 records · Page 9Linked to original sources
PubMed1986

Phylogenetic distance from man correlates with immunologic cross-reactivity among liver insulin receptors.

The hepatic insulin receptors from evolutionarily diverse species were evaluated to determine their ability to bind human insulin and their immunologic cross-reactivity with the human insulin receptor. We found that the liver membranes of each species possessed insulin receptors with remarkably similar affinities for human insulin. An immunoassay specific for human insulin receptor showed that the amount of shared antigenic determinants differed widely among the species tested and in general decreased as the phylogenetic distance from man increased. These data suggest that the ability to bind insulin has been highly conserved during evolution despite considerable variation in the primary structure of the insulin receptor.

Animals↗
PubMed2006

Surnames in Western Europe: a comparison of the subcontinental populations through isonymy.

We studied the isonymic structure of Western Europe using the distributions of 26.2 million surnames in 8 countries, 125 regions and 2094 towns of the Subcontinent. We found that, for the whole of Western Europe, Nei's distance was correlated with geographic distance (r=0.610+/-0.009). It was observed that at long geographic distances the isonymyc distance stays below linearity and tends to become asymptotic, and this was attributed to long distance migration. A dendrogram of the125 regions was built and the clusters identified by the dendrogram are almost exactly coincident with the nations of the Subcontinent. Random inbreeding calculated from isonymy, F(ST), was highest in Spanish regions, and lowest in France. The geographical distribution of alpha in 2094 towns, high in the Center and East of the Subcontinent and lower in Spain, is compatible with the settlement of subsequent waves of migrants moving from the West and from the South toward the centre of the Continent. The present surname structure of Western Europe is strictly linked to local languages.

Consanguinity↗
PubMed2002

An evaluation of direct orthogonal signal correction and other preprocessing methods for the classification of clinical study lots of a dermatological cream.

Different preprocessing methods (direct orthogonal signal correction (DOSC), standard normal variate (SNV), multiple scatter correction (MSC), first and second derivation, offset correction and detrend correction) are applied to two sets of NIR spectra of a dermatological cream with different concentrations of an active compound. The influence of these preprocessing methods on the classification of the samples into the right concentration class is evaluated using 1 and 3 nearest neighbour method (with Euclidean distance and correlation coefficient as distance parameters) as classification method. PLS and PCR modelling are also used to make a prediction of the concentration of the active compound. The direct orthogonal signal correction gives best results in most of the classification methods.

Dermatologic Agents↗
PubMed1983

Evaluation of a new defibrillation pathway--the tongue-epigastric route. I. Experimental studies in dogs.

The purpose of this study was to determine the efficacy of a tongue-epigastric defibrillation route in anesthetized dogs. Ventricular fibrillation was induced by rectangular pulses passed down a transvenous catheter into the right ventricle. Three groups of dogs were studied. Group I (15 dogs) received shocks from a 12 cm2 tongue electrode, a 50 cm2 circular, gelled self-adhesive electrode pad placed on the epigastrium and standard transthoracic defibrillator paddle electrodes. Shocks were given at energy levels of 50 to 460 joules (delivered energy, 50 ohm resistance). The success of the tongue-epigastric shocks in achieving defibrillation, and the resistance and current flow were determined at each energy level and compared with the same energy shocks from the standard transthoracic electrodes. In Group II (five dogs), comparisons were made between the 12 cm2 tongue electrode used in the first group of dogs and a larger tongue electrode of 40 cm2. In Group III (five dogs), intracardiac current flow (potential gradient) with tongue-epigastric and standard transthoracic electrodes was studied. In Group I, defibrillation success with the tongue-epigastric electrodes ranged from no success at 50 to 100 joules to 83% success at 460 joules. With standard transthoracic electrodes, success rates ranged from 65% at 50 joules to 100% at 300 joules. At all energies tested, the resistance was significantly higher and current significantly lower using tongue-epigastric compared with transthoracic electrodes. The higher tongue-epigastric resistance is probably related to the longer interelectrode distance; the correlation between interelectrode distance (x, in centimeters) and resistance (y, in ohms) in these dogs was y = 2.2x + 29.6, r = 0.78.(ABSTRACT TRUNCATED AT 250 WORDS)

Abdomen↗
PubMed2005

Patterns of genetic variation do not correlate with geographical distance in the reef-building coral Pocillopora meandrina in the South Pacific.

Dispersal may be a critical factor in the ability of reef-building corals to recover after major disturbances. We studied patterns of geographical structure using four microsatellite markers in seven South Pacific populations of Pocillopora meandrina, a major coral species from Polynesia. Variation within populations showed evidence of heterozygote deficiency. Genetic differentiation between populations was detected at a large scale (2000 km) between the Tonga and the Society Islands. Within the Society Islands, four of the five studied populations from Bora Bora, Moorea and Tahiti were not significantly different from each other. Unexpectedly, one of the three populations surveyed in Moorea was genetically different from the other two populations of this island (that were 5 and 10 km apart), and from the populations of the other two surveyed islands in this archipelago. We cannot rule out the possibility that this pattern is an equilibrium state, whereby short-range dispersal is locally more differentiating than long-range dispersal, as has been suggested by similar patterns reported in other studies. An alternative explanation that is globally consistent with all observations is that this is the signature of a large-scale destruction event, as for instance a bleaching event, followed by the recent restoration of populations by new colonists.

Animals↗
PubMed2000

How coil-cortex distance relates to age, motor threshold, and antidepressant response to repetitive transcranial magnetic stimulation.

Repetitive transcranial magnetic stimulation (rTMS) is a tool with antidepressant potential that uses a coil placed on the scalp to produce a powerful magnetic field that directly stimulates only the outermost cortex. MRI scans were obtained in 29 depressed adults involved in an rTMS antidepressant clinical treatment. These scans were analyzed to investigate the effect of distance from coil to cortex on clinical parameters. Longer motor cortex distance, but not prefrontal distance, strongly correlated with increased motor threshold (P<0.01). Clinical antidepressant response did not correlate with either distance. The rTMS antidepressant responders, however, were significantly younger (t=-2.430, P<0.05), and there appears to be a maximum threshold of age and distance to prefrontal cortex for response.

Adult↗
PubMed2002

Contribution of extraretinal signals to the scaling of object distance during self-motion.

We investigated the role of extraretinal information in the perception of absolute distance. In a computer-simulated environment, monocular observers judged the distance of objects positioned at different locations in depth while performing frontoparallel movements of the head. The objects were spheres covered with random dots subtending three different visual angles. Observers viewed the objects ateye level, either in isolation or superimposed on a ground floor. The distance and size of the spheres were covaried to suppress relative size information. Hence, the main cues to distance were the motion parallax and the extraretinal signals. In three experiments, we found evidence that (1) perceived distance is correlated with simulated distance in terms of precision and accuracy, (2) the accuracy in the distance estimate is slightly improved by the presence of a ground-floor surface, (3) the perceived distance is not altered significantly when the visual field size increases, and (4) the absolute distance is estimated correctly during self-motion. Conversely, stationary subjects failed to report absolute distance when they passively observed a moving object producing the same retinal stimulation, unless they could rely on knowledge of the three-dimensional movements.

Adolescent↗
PubMed2000

[Phylogenetic relationship of street rabies virus strains and their antigenic reactivity with antibodies induced by vaccine strains. II. Correlation between genetic distance and antibody reactivity].

The aim of these studies was the estimation of the influence of genetic divergence of reactivity with sera of people vaccinated against rabies of Polish rabies strains. Genetic similarity between CVS strain and street rabies strains of genotype 1 is relatively high. However, CVS strain showed the highest reactivity with standard immunoglobulin and sera of antirabies vaccinated people (measured by western blot method). It was completely different from street viruses. Cluster method based on genetic and serologic features indicated high difference between CVS strain and street rabies strains belonging to genotype 1 and genotype 5. On this basis CVS strain was classified as a separate cluster. The genetic divergence of rabies strains circulating in Poland suggests the need of permanent epidemiological and virological surveillance. Strains different in their genotypic and biotypic characteristics should be estimated according to their antigenic similarity to vaccine strain. In practice neutralisation test using mono- and polyclonal sera should be performed. Strains isolated from new or atypical animal species should be studied first of all.

Animals↗
PubMed1996

Genetic variation in the population of Ibiza (Spain): genetic structure, geography, and language.

A sample of 203 individuals from Ibiza (Balearic Islands, Spain) were tested for blood group and serum protein genetic variation and compared with other circum-Mediterranean populations. Allele frequencies were calculated for the following blood group and serum systems: ABO, Rh, MNSs, P, Lewis, Duffy, Kell, ORM, GC, TF, PI, and HP. The allele frequencies from Ibiza were compared with those from other Balearic Islands (Majorca and Minorca) and with related European and North African groups using an assortment of analytical methods (genetic distances, R matrix analysis, and Mantel tests). R matrix analysis revealed that Ibiza is genetically different from the other Balearic populations and, because of gene flow from Spain, clusters with European groups. The level of genetic microdifferentiation of the Mediterranean populations, measured by RST (average of the R matrix diagonal elements, rii), is 0.028. An examination of the relationship between genetic, geographic, and linguistic distances by Mantel tests revealed that genetic distances are significantly correlated with linguistic distances, whereas the genetic distances are not significantly correlated with geographic distances. The plot of mean per locus heterozygosity versus the genetic distance from the centroid of distribution revealed that all three Balearic Islands have experienced considerable gene flow but that Ibiza has been most affected by the action of stochastic processes.

Blood Group Antigens↗
PubMed2006

The size of the cochlea and predictions of insertion depth angles for cochlear implant electrodes.

AIMS: To establish normative data on the size of the basal turn of the cochlea using high-resolution computed tomography of the temporal bone in adults and children. To determine whether final insertion depth angle for a perimodiolar cochlear implant electrode varies according to cochlear size. METHODS: Forty-two patients screened for cochlear anomaly using computed tomography were randomly selected from patients with otologic disease. Reconstruction of the full basal turn was performed for both ears using a 1.0-mm layer, minimum intensity projection. The largest distance from the round window to the lateral wall (distance A) and the perpendicular distance (B) were measured. Distances were averaged between ears for each individual. In addition, 15 patients were implanted with the Nucleus 24 Contour Advance electrode array using a linear insertion depth of either 17 mm (n = 9) or 19 mm (n = 6). Postoperative X-rays were analyzed using the method of Xu et al. [Am J Otol 2000;21:49-56] to obtain the insertion depth angles for individual electrodes. RESULTS: Mean distance A was 9.23 mm (SD = 0.53, range 7.9-10.8 mm). Perpendicular distance B was significantly correlated with distance A (r2 = 0.57, p < 0.001). The mean difference in insertion depth angle between the 17 and 19 mm groups was 80 degrees . A statistically significant correlation (r2 = 0.51) was found between distance A and the insertion depth angle for the 17 mm group. CONCLUSIONS: The cochlear size measure distance A was repeatable to within the resolution of the high-resolution computed tomography image data. The basal turn of the normally formed cochlea is variable in size. These variations in size would produce >5.0 mm variation in the length of the lateral wall to the point consistent with an insertion depth angle of 360 degrees . Cochlear size influenced final insertion depth angles obtained for the perimodiolar Nucleus 24 Contour Advance electrode.

Adolescent↗
PubMed1983

Correlations between laboratory testing and distance running performance in marathoners of similar performance ability.

Correlations between distance running performance and laboratory testing were examined in 11 marathoners of similar fitness (VO2max 66.4 +/- 1.7 ml/kg X min). They performed a graded treadmill test and a subsequent 30 km cross-country run. Heart rate, oxygen intake, blood lactate, and plasma catecholamines were measured during the treadmill test. Lactate equivalent, individual lactate threshold, 4 mmol lactate threshold, submaximum (16 km/h running velocity) lactate behavior, submaximum catecholamine responses, submaximum lactate-catecholamine product, measured VO2max, and extrapolated VO2max were examined for their adequacy in the evaluation of distance running capacity. Race times and free urine catecholamines were estimated in the field experiment. Direct correlations were found between race times and minimum lactate equivalent (r = 0.69), submaximum lactate levels (r = 0.52), submaximum catecholamine responses (r = 0.69), submaximum lactate-catecholamine product (r = 0.79), respectively. Inverse correlations were observed between race times and oxygen intake at individual lactate threshold (r = -0.68), 4 mmol lactate threshold (r = -0.76), measured VO2max (r = -0.71), and extrapolated VO2max (r = -0.63). Further correlations were found between submaximum noradrenaline and lactate behavior (r = 0.53), as well as between noradrenaline and adrenaline responses (r = 0.72). No significant correlation was observed between relative heart volumes or catecholamine excretion and race times.

Adult↗