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Cm Intervals (cm + interval)
Selected AbstractsFine mapping of a sedative-hypnotic drug withdrawal locus on mouse chromosome 11GENES, BRAIN AND BEHAVIOR, Issue 1 2006H. M. Hood We have established that there is a considerable amount of common genetic influence on physiological dependence and associated withdrawal from sedative-hypnotic drugs including alcohol, benzodiazepines, barbiturates and inhalants. We previously mapped two loci responsible for 12 and 9% of the genetic variance in acute alcohol and pentobarbital withdrawal convulsion liability in mice, respectively, to an approximately 28-cM interval of proximal chromosome 11. Here, we narrow the position of these two loci to a 3-cM interval (8.8 Mb, containing 34 known and predicted genes) using haplotype analysis. These include genes encoding four subunits of the GABAA receptor, which is implicated as a pivotal component in sedative-hypnotic dependence and withdrawal. We report that the DBA/2J mouse strain, which exhibits severe withdrawal from sedative-hypnotic drugs, encodes a unique GABAA receptor ,2 subunit variant compared with other standard inbred strains including the genetically similar DBA/1J strain. We also demonstrate that withdrawal from zolpidem, a benzodiazepine receptor agonist selective for ,1 subunit containing GABAA receptors, is influenced by a chromosome 11 locus, suggesting that the same locus (gene) influences risk of alcohol, benzodiazepine and barbiturate withdrawal. Our results, together with recent knockout studies, point to the GABAA receptor ,2 subunit gene (Gabrg2) as a promising candidate gene to underlie phenotypic differences in sedative-hypnotic physiological dependence and associated withdrawal episodes. [source] Refined linkage to the RDP/DYT12 locus on 19q13.2 and evaluation of GRIK5 as a candidate geneMOVEMENT DISORDERS, Issue 7 2004Christoph Kamm MD Abstract By examining two previously described families with rapid-onset dystonia parkinsonism, we have identified a key recombination event that places the disease locus (DYT12) into a 5.9 cM interval flanked by markers D19S224 and D19S900. Evaluation of a positional candidate gene, the glutamate receptor subunit GRIK5, revealed no mutations. © 2004 Movement Disorder Society [source] Linkage analysis of schizophrenia to chromosome 15AMERICAN JOURNAL OF MEDICAL GENETICS, Issue 8 2001Dr. Pablo V. Gejman Abstract We have mapped a sample of 68 families consisting of one or more affected sibling pairs with schizophrenia or schizoaffective disorder with 20 markers spanning all of chromosome 15 to investigate whether there is a locus on chromosome 15 that confers an increased susceptibility to schizophrenia using parametric and nonparametric linkage analyses. Allele sharing identical by descent and multipoint maximum likelihood score (MLS) statistics were employed. Results show excess allele sharing for multiple markers in 15q11.2,q25, a chromosomal region previously found linked to a decrease in the normal inhibition of the P50 auditory-evoked response to the second of paired stimuli, a decrease associated with schizophrenia. Excess allele sharing was found for markers spanning about 48 cM in 15q11.2,q25 (D15S1002,D15S1023). The greatest single point allele sharing was found at D15S659 (62.6%). The multipoint MLS scores were greater than 1.0 in the 30,52 cM interval delimited by ACTC and D15S150, with a maximum value of 2.0 with GENEHUNTER PLUS near D15S1039. © 2001 Wiley-Liss, Inc. [source] A genomewide linkage study of age at onset in schizophrenia,AMERICAN JOURNAL OF MEDICAL GENETICS, Issue 5 2001Alastair G. Cardno Abstract There is strong evidence for a genetic contribution to age at onset of schizophrenia, which probably involves both susceptibility loci for schizophrenia and modifying loci acting independent of disease risk. We sought evidence of linkage to loci that influence age at onset of schizophrenia in a sample of 94 affected sibling pairs with DSM-IV schizophrenia or schizoaffective disorder, and age at first psychiatric contact of 45 years or less. Individuals were genotyped for 229 microsatellite markers spaced at approximately 20 cM intervals throughout the genome. Loci contributing to age at onset were sought by a quantitative maximum-likelihood multipoint linkage analysis using MAPMAKER/SIBS. A nonparametric multipoint analysis was also performed. The genomewide significance of linkage results was assessed by simulation studies. There were six maximum-likelihood LOD score peaks of 1.5 or greater, the highest being on chromosome 17q (LOD,=,2.54; genomewide P,=,0.27). This fulfils Lander and Kruglyak's [1995: Nat Genet 11:241,247] criteria for suggestive linkage in that it would be expected to occur once or less (0.3 times) per genome scan. However, this finding should be treated with caution because the LOD score appeared to be almost solely accounted for by the pattern of ibd sharing at one marker (D17S787), with virtually no evidence of linkage over flanking markers. None of the linkage results achieved genomewide statistical significance, but the LOD score peak on chromosome 13q (LOD,=,1.68) coincided with the region showing maximum evidence for linkage in the study by Blouin et al. [1998: Nat Genet 20:70,73] of categorical schizophrenia. © 2001 Wiley-Liss, Inc. [source] Integration of magnetism and heavy metal chemistry of soils to quantify the environmental pollution in Kathmandu, NepalISLAND ARC, Issue 4 2005Pitambar Gautam Abstract Soil profiles of the Kathmandu urban area exhibit significant variations in magnetic susceptibility (,) and saturation isothermal remanence (SIRM), which can be used to discriminate environmental pollution. Magnetic susceptibility can be used to delineate soil intervals by depth into normal (< 10,7 m3/kg), moderately enhanced (10,7,< 10,6 m3/kg) and highly enhanced (, 10,6 m3/kg). Soils far from roads and industrial sites commonly fall into the ,normal' category. Close to a road corridor, soils at depths of several centimeters have the highest ,, which remains high within the upper 20 cm interval, and decreases with depth through ,moderately magnetic' to ,normal' at approximately 30,40 cm. Soils in the upper parts of profiles in urban recreational parks have moderate ,. Soil SIRM has three components of distinct median acquisition fields (B1/2): soft (30,50 mT, magnetite-like phase), intermediate (120,180 mT, probably maghemite or soft coercivity hematite) and hard (550,600 mT, hematite). Close to the daylight surface, SIRM is dominated by a soft component, implying that urban pollution results in enrichment by a magnetite-like phase. Atomic absorption spectrometry of soils from several profiles for heavy metals reveals remarkable variability (ratio of maximum to minimum contents) of Cu (16.3), Zn (14.8) and Pb (9.3). At Rani Pokhari, several metals are well correlated with ,, as shown by a linear relationship between the logarithmic values. At Ratna Park, however, both , and SIRM show significant positive correlation with Zn, Pb and Cu, but poor and even negative correlation with Fe (Mn), Cr, Ni and Co. Such differences result from a variety of geogenic, pedogenic, biogenic and man-made factors, which vary in time and space. Nevertheless, for soil profiles affected by pollution (basically traffic-related), , exhibits a significant linear relationship with a pollution index based on the contents of some urban elements (Cu, Pb, Zn), and therefore it serves as an effective parameter for quantifying the urban pollution. [source] Small-scale variability in surface moisture on a fine-grained beach: implications for modeling aeolian transportEARTH SURFACE PROCESSES AND LANDFORMS, Issue 10 2009Brandon L. Edwards Abstract Small-scale variations in surface moisture content were measured on a fine-grained beach using a Delta-T Theta probe. The resulting data set was used to examine the implications of small-scale variability for estimating aeolian transport potential. Surface moisture measurements were collected on a 40 cm × 40 cm grid at 10 cm intervals, providing a total of 25 measurements for each grid data set. A total of 44 grid data sets were obtained from a representative set of beach sub-environments. Measured moisture contents ranged from about 0% (dry) to 25% (saturated), by weight. The moisture content range within a grid data set was found to vary from less than 1% to almost 15%. The magnitude of within-grid variability varied consistently with the mean moisture content of the grid sets, following an approximately normal distribution. Both very wet and very dry grid data sets exhibited little internal variability in moisture content, while intermediate moisture contents were associated with higher levels of variability. Thus, at intermediate moisture contents it was apparent that some portions of the beach surface could be dry enough to allow aeolian transport (i.e. moisture content is below the critical threshold), while adjacent portions are too wet for transport to occur. To examine the implications of this finding, cumulative distribution functions were calculated to model the relative proportions of beach surface area expected to be above or below specified threshold moisture levels (4%, 7%, and 14%). It was found that the implicit inclusion of small-scale variability in surface moisture levels typically resulted in changes of less than 1% in the beach area available for transport, suggesting that this parameter can be ignored at larger spatial scales. Copyright © 2009 John Wiley & Sons, Ltd. [source] Current practice compared with the international guidelines: endoscopic surveillance of Barrett's esophagusJOURNAL OF EVALUATION IN CLINICAL PRACTICE, Issue 5 2007Nassira Amamra MPH Abstract Rationale, aims and objectives, To describe the current practice for the surveillance of patients with Barrett's esophagus, to compare this practice with the national guidelines published by the French Society of Digestive Endoscopy in 1998 and to identify the factors associated with the compliance to guidelines. Method, To determine the attitudes of French hepatogastroenterologists to screening for Barrett's oesophagus, a postal anonymous questionnaire survey was undertaken. It was sent to 246 hepatogastroenterologists in the Rhone-Alpes area. We defined eight criteria allowed to assess the conformity of practices with the guidelines. We created three topics composed of several criterion. The topics analysed were ,Biopsies', ,Surveillance' and the diagnosis of high grade dysplasia. We studied the factors which could be associated with the compliance with the guidelines. Results, The response rate was 81.3%. For 58.0% of the gastroenterologists, endoscopic biopsy sampling were made according to French guidelines (four-quadrant biopsies at 2 cm intervals). Agreement was 78.0% regarding the interval of surveillance for no dysplasia (every 2 or 3 years) and 78.5% regarding the low-grade dysplasia (every 6 or 12 months). For the management of high-grade dysplasia, 28.6% actually confirm the diagnosis by a second anatomopathologist and 42.0% treated by proton pump inhibitor during 2 months. Concerning the biopsies, the young gastroenterologists and gastroenterologists practising in university hospitals had a better adherence to the guidelines (Relative Risk: 2.22, 95% CI 1.25,3.95 and 3.74, 95% CI 1.04,13.47, respectively). The other factors of risk were not statistically significant. Conclusions, The endoscopic follow-up is mostly realized in accordance with the national guidelines. However, there is a wide variability in individual current practice. [source] Rapid seismic reflection imaging at the Clovis period Gault site in central TexasARCHAEOLOGICAL PROSPECTION, Issue 4 2007John A. Hildebrand Abstract Using a modified seismic reflection imaging system with rapid translation of receivers, stratigraphic profiles were collected at the Gault site in central Texas. For rapid data collection, spikeless geophone receivers were placed in sand-filled bags at tight spacing, and these receivers were rapidly pulled along the ground surface between shots. Shots were produced by a small hammer strike to a vertical pipe at 20-cm intervals. High quality ultrashallow seismic reflection profiles were collected at a rate of 25,m,h,1, significantly faster than what is possible with conventional seismic reflection imaging using individually planted geophones. Ground-penetrating radar was attempted, but abandoned owing to the poor penetration of the radar signals in the clay soils present at the Gault site. Electromagnetic induction grids were collected surrounding each seismic reflection profile, and provided information on near-surface ground water. Seismic reflection images of Gault site stratigraphy provided greater depth penetration than accessible from backhoe trenching and coring, and helped to better outline the site geological context. Seismic images reveal coherent reflections at shallow depths (0,2.5,m), and extensive scattering at deeper levels (2.5,8,m), underlain by reflection-free zones. These data are interpreted as clay and gravel layers overlaying palaeostream channels carved into the limestone bedrock. Where comparative data were available, the geophysical findings were corroborated by observations of site stratigraphy in archaeological excavation units, backhoe trenches and cores. Seismic reflection studies at the Gault site revealed a palaeochannel filled with pre-Clovis age sediments. Pre-Clovis age sediments are not known to occur at other locations within the Gault site. They provide a unique opportunity to test for cultural remains of great antiquity. Copyright © 2007 John Wiley & Sons, Ltd. [source] A high-resolution diatom record of late-Quaternary sea-surface temperatures and oceanographic conditions from the eastern Norwegian SeaBOREAS, Issue 4 2002CHRISTOPHER J. A. BIRKS Core MD95-2011 was taken from the eastern Vøring Plateau, near the Norwegian coast. The section between 250 and 750 cm covers the time period from 13 000 to 2700 cal. yr BP (the Lateglacial and much of the Holocene). Samples at 5 cm intervals were analysed for fossil diatoms. A data-set of 139 modern sea-surface diatom samples was related to contemporary sea-surface temperatures (SSTs) using two different numerical methods. The resulting transfer functions were used to reconstruct past sea-surface temperatures from the fossil diatom assemblages. After the cold Younger Dryas with summer SSTs about 6°C, temperatures warmed rapidly to about 13°C. One of the fluctuations in the earliest Holocene can be related to the Pre-Boreal Oscillation, but SSTs were generally unstable until about 9700 cal. yr BP. Evidence from diatom concentration and magnetic susceptibility suggests a change and stabilization of water currents associated with the final melting of the Scandinavian Ice Sheet at c. 8100 cal. yr BP. A period of maximum warmth between 9700 and 6700 cal. yr BP had SSTs 3,5°C warmer than at present. Temperatures cooled gradually until c. 3000 cal. yr BP, and then rose slightly around 2750 cal. yr BP. The varimax factors derived from the Imbrie & Kipp method for sea-surface-temperature reconstructions can be interpreted as water-masses. They show a dominance of Arctic Waters and Sea Ice during the Younger Dryas. The North Atlantic current increased rapidly in strength during the early Holocene, resulting in warmer conditions than previously. Since about 7250 cal. yr BP, Norwegian Atlantic Water gradually replaced the North Atlantic Water, and this, in combination with decreasing summer insolation, led to a gradual cooling of the sea surface. Terrestrial systems in Norway and Iceland responded to this cooling and the increased supply of moisture by renewed glaciation. Periods of glacial advance can be correlated with cool oscillations in the SST reconstructions. By comparison with records of SSTs from other sites in the Norwegian Sea, spatial and temporal changes in patterns of ocean water-masses are reconstructed, to reveal a complex system of feedbacks and influences on the climate of the North Atlantic and Norway. [source] | ||||||||||||||||