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1.
AJNR Am J Neuroradiol ; 39(5): 935-941, 2018 05.
Article in English | MEDLINE | ID: mdl-29545251

ABSTRACT

BACKGROUND AND PURPOSE: Tension-type and migraine-type headaches are the most common chronic paroxysmal disorders of childhood. The goal of this study was to compare regional cerebral volumes and diffusion in tension-type and migraine-type headaches against published controls. MATERIALS AND METHODS: Patients evaluated for tension-type or migraine-type headache without aura from May 2014 to July 2016 in a single center were retrospectively reviewed. Thirty-two patients with tension-type headache and 23 with migraine-type headache at an average of 4 months after diagnosis were enrolled. All patients underwent DWI at 3T before the start of pharmacotherapy. Using atlas-based DWI analysis, we determined regional volumetric and diffusion properties in the cerebral cortex, thalamus, caudate, putamen, globus pallidus, hippocampus, amygdala, nucleus accumbens, brain stem, and cerebral white matter. Multivariate analysis of covariance was used to test for differences between controls and patients with tension-type and migraine-type headaches. RESULTS: There were no significant differences in regional brain volumes between the groups. Patients with tension-type and migraine-type headaches showed significantly increased ADC in the hippocampus and brain stem compared with controls. Additionally, only patients with migraine-type headache showed significantly increased ADC in the thalamus and a trend toward increased ADC in the amygdala compared with controls. CONCLUSIONS: This study identifies early cerebral diffusion changes in patients with tension-type and migraine-type headaches compared with controls. The hypothesized mechanisms of nociception in migraine-type and tension-type headaches may explain the findings as a precursor to structural changes seen in adult patients with chronic headache.


Subject(s)
Brain/diagnostic imaging , Brain/pathology , Migraine Disorders/diagnostic imaging , Migraine Disorders/pathology , Tension-Type Headache/diagnostic imaging , Tension-Type Headache/pathology , Adolescent , Child , Child, Preschool , Chronic Disease , Female , Humans , Infant , Magnetic Resonance Imaging , Male , Retrospective Studies
2.
J Mol Med (Berl) ; 93(12): 1297-309, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26330151

ABSTRACT

UNLABELLED: Recent studies implicate TRPV4 receptors in visceral pain signaling and intestinal inflammation. Our aim was to evaluate the role of TRPV4 in the control of gastrointestinal (GI) motility and to establish the underlying mechanisms. We used immunohistochemistry and PCR to study TRPV4 expression in the GI tract. The effect of TRPV4 activation on GI motility was characterized using in vitro and in vivo motility assays. Calcium and nitric oxide (NO) imaging were performed to study the intracellular signaling pathways. Finally, TRPV4 expression was examined in the colon of healthy human subjects. We demonstrated that TRPV4 can be found on myenteric neurons of the colon and is co-localized with NO synthase (NOS-1). In vitro, the TRPV4 agonist GSK1016790A reduced colonic contractility and increased inhibitory neurotransmission. In vivo, TRPV4 activation slowed GI motility and reduced stool production in mouse models mimicking pathophysiological conditions. We also showed that TRPV4 activation inhibited GI motility by reducing NO-dependent Ca(2+) release from enteric neurons. In conclusion, TRPV4 is involved in the regulation of GI motility in health and disease. KEY MESSAGES: • Recent studies implicate TRPV4 in pain signaling and intestinal inflammation. • Our aim was to characterize the role of TRPV4 in the control of GI motility. • We found that TRPV4 activation reduced colonic contractility. • Our studies also showed altered TRPV4 mRNA expression in IBS-C patients. • TRPV4 may be a novel pharmacological target in functional GI diseases.


Subject(s)
Colon/physiology , Gastrointestinal Motility/genetics , Nitric Oxide/metabolism , Synaptic Transmission/genetics , TRPV Cation Channels/genetics , TRPV Cation Channels/metabolism , Adult , Aged , Aged, 80 and over , Animals , Case-Control Studies , Colon/drug effects , Colon/physiopathology , Disease Models, Animal , Female , Gastrointestinal Motility/drug effects , Gene Expression , Guanylate Cyclase/metabolism , Humans , Irritable Bowel Syndrome/drug therapy , Irritable Bowel Syndrome/genetics , Irritable Bowel Syndrome/metabolism , Irritable Bowel Syndrome/physiopathology , Leucine/analogs & derivatives , Leucine/pharmacology , Male , Mice , Mice, Knockout , Middle Aged , Models, Biological , Muscle Contraction/drug effects , Muscle, Smooth/drug effects , Muscle, Smooth/metabolism , Myenteric Plexus/metabolism , Nitric Oxide Synthase/metabolism , Sulfonamides/pharmacology , TRPV Cation Channels/antagonists & inhibitors
3.
J Dairy Sci ; 95(2): 864-75, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22281351

ABSTRACT

Single nucleotide polymorphism (SNP) associations with milk production traits found to be significant in different screening experiments, including SNP in genes hypothesized to be in gene pathways affecting milk production, were tested in a validation population to confirm their association. In total, 423 SNP were genotyped across 411 Holstein bulls, and their association with 6 milk production traits--Australian Selection Index (indicating the profitability of an animal's milk production), protein, fat, and milk yields, and protein and fat composition--were tested using single SNP regressions. Seventy-two SNP were significantly associated with one or more of the traits; their effects were in the same direction as in the screening experiment and therefore their association was considered validated. An over-representation of SNP (43 of the 423) on chromosome 20 was observed, including a SNP in the growth hormone receptor gene previously published as having an association with protein composition and protein and milk yields. The association with protein composition was confirmed in this experiment, but not the association with protein and milk yields. A multiple SNP regression analysis for all SNP on chromosome 20 was performed for all 6 traits, which revealed that this mutation was not significantly associated with any of the milk production traits and that at least 2 other quantitative trait loci were present on chromosome 20.


Subject(s)
Cattle/genetics , Lactation/genetics , Polymorphism, Single Nucleotide/genetics , Quantitative Trait, Heritable , Animals , Cattle/physiology , Chromosome Mapping/veterinary , Female , Genome/genetics , Genotype , Lactation/physiology , Male , Milk/chemistry , Milk/metabolism
4.
Anim Genet ; 40(2): 176-84, 2009 Apr.
Article in English | MEDLINE | ID: mdl-19067671

ABSTRACT

A number of cattle breeds have become highly specialized for milk or beef production, following strong artificial selection for these traits. In this paper, we compare allele frequencies from 9323 single nucleotide polymorphism (SNP) markers genotyped in dairy and beef cattle breeds averaged in sliding windows across the genome, with the aim of identifying divergently selected regions of the genome between the production types. The value of the method for identifying selection signatures was validated by four sources of evidence. First, differences in allele frequencies between dairy and beef cattle at individual SNPs were correlated with the effects of those SNPs on production traits. Secondly, large differences in allele frequencies generally occurred in the same location for two independent data sets (correlation 0.45) between sliding window averages. Thirdly, the largest differences in sliding window average difference in allele frequencies were found on chromosome 20 in the region of the growth hormone receptor gene, which carries a mutation known to have an effect on milk production traits in a number of dairy populations. Finally, for the chromosome tested, the location of selection signatures between dairy and beef cattle was correlated with the location of selection signatures within dairy cattle.


Subject(s)
Cattle/genetics , Alleles , Animals , Breeding , Cattle/growth & development , Cattle/physiology , Chromosome Mapping/veterinary , Databases, Genetic , Female , Gene Frequency , Genotype , Lactation , Male , Meat , Milk/metabolism , Polymorphism, Single Nucleotide , Receptors, Somatotropin/genetics
5.
Anim Genet ; 39(2): 105-11, 2008 Apr.
Article in English | MEDLINE | ID: mdl-18241301

ABSTRACT

The extent and pattern of linkage disequilibrium (LD) between closely spaced markers contain information about population history, including past population size and selection history. Selection signatures can be identified by comparing the LD surrounding a putative selected allele at a locus to the putative non-selected allele. In livestock populations, locations of selection signatures identified in this way should be correlated with QTL affecting production traits, as the populations have been under strong artificial selection for these traits. We used a dense SNP map of bovine chromosome 6 to characterize the pattern of LD on this chromosome in Norwegian Red cattle, a breed which has been strongly selected for milk production. The pattern of LD was generally consistent with strong selection in regions containing QTL affecting milk production traits, including a strong selection signature in a region containing a mutation known to affect milk production. The results demonstrate that in livestock populations, the origin of selection signatures will often be QTL for livestock production traits, and illustrate the value of selection signatures in uncovering new mutations with potential effects on quantitative traits.


Subject(s)
Cattle/genetics , Chromosome Mapping , Polymorphism, Single Nucleotide , Selection, Genetic , Animals , Computer Simulation , Female , Gene Frequency , Genetic Markers , Linkage Disequilibrium , Male , Models, Genetic , Norway , Reproduction/genetics
6.
Mol Ecol ; 15(6): 1481-92, 2006 May.
Article in English | MEDLINE | ID: mdl-16629805

ABSTRACT

Anthropogenic activities continue to cause massive fragmentation and reduction of forest area worldwide. With fragmentation and reduction of habitat recognized as the greatest threats to biodiversity, the implementation of improved, informed and conservation-based forestry practices is essential, and requires a greater understanding of the responses of different organisms to forest fragmentation. While genetic techniques can add invaluable insights to fragmentation studies they have rarely been employed, particularly for multiple species. In the present study, we combined genetic information, obtained from allozyme loci and anonymous single copy nuclear DNA markers, with ecological data to investigate the impacts of forest fragmentation on two log-dwelling beetles with different life histories, in an 'islands of bush in a sea of pine' model, at Tumut in New South Wales, Australia. Both the relatively mobile (i.e. has high dispersal ability and/or broad habitat range) Adelium calosomoides and the less mobile Apasis puncticeps showed reduced mobility and gene flow in fragmented compared to continuous forest: there was significantly greater isolation by distance and stronger local structure revealed by spatial autocorrelation in fragmented forest. Analysis of patch and species characteristics revealed that genetic and demographic structure may be influenced by log degradation class for both species, and number of potential dispersal barriers, distance from continuous forest and desiccation intolerance/moisture preference for Ap. puncticeps. Thus the pine plantation matrix poses a barrier or filter for gene flow and mobility in both beetle species.


Subject(s)
Coleoptera/genetics , Environment , Geography , Trees/growth & development , Animals , Biodiversity , Coleoptera/physiology , Gene Flow , Genotype , Industry , Population Density , Victoria
8.
Curr Anthropol ; 999(1): 000357-000384, 2000 Jun.
Article in English | MEDLINE | ID: mdl-11045927

ABSTRACT

Over the past 40 years, traditional perspectives on the constitution of human groups have been subjected to stringent critique within anthropology. This began with the dismantling of accepted "race" divisions after World War II and continued with analyses of the meaning and reality of African "tribal" distinctions from the 1960s until the present. Archaeologists, ethnographers, linguists, and historians of Africa now work within a research milieu where social interactions, cultural exchange, and the dynamic nature of group identifications are accepted as a normal part of the human experience. At the same time, new techniques have been developed for the examination of human history, techniques based upon an expanding repertoire of tools for the analysis of genetic variability in human populations. Perhaps the most striking result of this research has been Cavalli-Sforza, Menozzi, and Piazza's The History and Geography of Human Genes. Rather less attention has been paid, however, to the conceptual relationships between the human groups defined through such analyses, in Africa and elsewhere, and those defined through other kinds of research. This paper is a preliminary examination of the fit between genetic, archaeological, and ethnographic data on the African past.

9.
Curr Anthropol ; 41(3): 357-384, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10768880

ABSTRACT

Over the past 40 years, traditional perspectives on the constitution of human groups have been subjected to stringent critique within anthropology. This began with the dismantling of accepted "race" divisions after World War II and continued with analyses of the meaning and reality of African "tribal" distinctions from the 1960s until the present. Archaeologists, ethnographers, linguists, and historians of Africa now work within a research milieu where social interactions, cultural exchange, and the dynamic nature of group identifications are accepted as a normal part of the human experience. At the same time, new techniques have been developed for the examination of human history, techniques based upon an expanding repertoire of tools for the analysis of genetic variability in human populations. Perhaps the most striking result of this research has been Cavalli-Sforza, Menozzi, and Piazza's The History and Geography of Human Genes. Rather less attention has been paid, however, to the conceptual relationships between the human groups defined through such analyses, in Africa and elsewhere, and those defined through other kinds of research. This paper is a preliminary examination of the fit between genetic, archaeological, and ethnographic data on the African past.

10.
Curr Anthropol ; 999(2): 000357-000384, 2000 Jun.
Article in English | MEDLINE | ID: mdl-11045932

ABSTRACT

Over the past 40 years, traditional perspectives on the constitution of human groups have been subjected to stringent critique within anthropology. This began with the dismantling of accepted "race" divisions after World War II and continued with analyses of the meaning and reality of African "tribal" distinctions from the 1960s until the present. Archaeologists, ethnographers, linguists, and historians of Africa now work within a research milieu where social interactions, cultural exchange, and the dynamic nature of group identifications are accepted as a normal part of the human experience. At the same time, new techniques have been developed for the examination of human history, techniques based upon an expanding repertoire of tools for the analysis of genetic variability in human populations. Perhaps the most striking result of this research has been Cavalli-Sforza, Menozzi, and Piazza's The History and Geography of Human Genes. Rather less attention has been paid, however, to the conceptual relationships between the human groups defined through such analyses, in Africa and elsewhere, and those defined through other kinds of research. This paper is a preliminary examination of the fit between genetic, archaeological, and ethnographic data on the African past.

11.
Chronic Dis Can ; 18(2): 70-90, 1997.
Article in English | MEDLINE | ID: mdl-9268286

ABSTRACT

This paper provides a brief history of Canadian health surveys and a review of health or health-related surveys from the first national household survey in 1950/51 to the present time. Surveys have evolved from collecting information on health care utilization, health status and some risk behaviours to a wider range of health determinants following the 1974 Lalonde report. In addition to the occasional cross-sectional surveys, there are periodic surveys, longitudinal surveys, school-based surveys and surveys based on subgroups in the population or specific topic areas. The survey review is presented in the following four tables: Table 1 summarizes national surveys including such information as the date(s) and frequency of data collection, topic areas, target population, sample size and response rate for each survey; Table 2 provides the same information for provincial surveys; both tables point to Table 3, which supplements the previous information with survey sponsors and contacts; Table 4 provides similar information for commercial surveys. This reference, which will be updated periodically, is intended to act as a source of information and support in the development of new surveys.


Subject(s)
Health Care Surveys/history , Health Surveys , Canada/epidemiology , History, 20th Century , Humans , Research Design , Research Support as Topic/history
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