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Author (up) de Borst, A.W.; Sack, A.T.; Jansma, B.M.; Esposito, F.; de Martino, F.; Valente, G.; Roebroeck, A.; di Salle, F.; Goebel, R.; Formisano, E. file  url
  Title Integration of “what” and “where” in frontal cortex during visual imagery of scenes Type Journal Article
  Year 2012 Publication NeuroImage Abbreviated Journal Neuroimage  
  Volume 60 Issue 1 Pages 47-58  
  Keywords Adolescent; Adult; Electroencephalography; Female; Frontal Lobe--physiology; Functional Neuroimaging; Humans; Imagination--physiology; Magnetic Resonance Imaging; Male; Young Adult  
  Abstract Imagination is a key function for many human activities, such as reminiscing, learning, or planning. Unravelling its neuro-biological basis is paramount to grasp the essence of our thoughts. Previous neuroimaging studies have identified brain regions subserving the visualisation of “what?” (e.g. faces or objects) and “where?” (e.g. spatial layout) content of mental images. However, the functional role of a common set of involved regions – the frontal regions – and their interplay with the “what” and “where” regions, has remained largely unspecified. This study combines functional MRI and electroencephalography to examine the full-brain network that underlies the visual imagery of complex scenes and to investigate the spectro-temporal properties of its nodes, especially of the frontal cortex. Our results indicate that frontal regions integrate the “what” and “where” content of our thoughts into one visually imagined scene. We link early synchronisation of anterior theta and beta oscillations to regional activation of right and central frontal cortices, reflecting retrieval and integration of information. These frontal regions orchestrate remote occipital-temporal regions (including calcarine sulcus and parahippocampal gyrus) that encode the detailed representations of the objects, and parietal “where” regions that encode the spatial layout into forming one coherent mental picture. Specifically the mesial superior frontal gyrus appears to have a principal integrative role, as its activity during the visualisation of the scene predicts subsequent performance on the imagery task.  
  Call Number Serial 386  
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Author (up) de Groat, W.C.; Yoshimura, N. file  url
  Title Changes in afferent activity after spinal cord injury Type Journal Article
  Year 2010 Publication Neurourology and Urodynamics Abbreviated Journal Neurourol Urodyn  
  Volume 29 Issue 1 Pages 63-76  
  Keywords Afferent Pathways/metabolism/*physiopathology; Animals; Central Nervous System/metabolism/*physiopathology; Ganglia, Spinal/metabolism/*physiopathology; Genetic Therapy/methods; Humans; Mechanotransduction, Cellular; Nerve Fibers, Myelinated; Nerve Fibers, Unmyelinated; Nerve Growth Factor/metabolism; Neuroanatomical Tract-Tracing Techniques; Neuronal Plasticity; Patch-Clamp Techniques; Pituitary Adenylate Cyclase-Activating Polypeptide/metabolism; Potassium Channels/metabolism; Recovery of Function; Reflex; Sodium Channels/metabolism; Spinal Cord Injuries/complications/metabolism/*physiopathology/therapy; Urinary Bladder/*innervation; Urinary Bladder, Neurogenic/etiology/metabolism/*physiopathology/therapy; *Urination; gamma-Aminobutyric Acid/metabolism  
  Abstract AIMS: To summarize the changes that occur in the properties of bladder afferent neurons following spinal cord injury. METHODS: Literature review of anatomical, immunohistochemical, and pharmacologic studies of normal and dysfunctional bladder afferent pathways. RESULTS: Studies in animals indicate that the micturition reflex is mediated by a spinobulbospinal pathway passing through coordination centers (periaqueductal gray and pontine micturition center) located in the rostral brain stem. This reflex pathway, which is activated by small myelinated (Adelta) bladder afferent nerves, is in turn modulated by higher centers in the cerebral cortex involved in the voluntary control of micturition. Spinal cord injury at cervical or thoracic levels disrupts voluntary voiding, as well as the normal reflex pathways that coordinate bladder and sphincter function. Following spinal cord injury, the bladder is initially areflexic but then becomes hyperreflexic due to the emergence of a spinal micturition reflex pathway. The recovery of bladder function after spinal cord injury is dependent in part on the plasticity of bladder afferent pathways and the unmasking of reflexes triggered by unmyelinated, capsaicin-sensitive, C-fiber bladder afferent neurons. Plasticity is associated with morphologic, chemical, and electrical changes in bladder afferent neurons and appears to be mediated in part by neurotrophic factors released in the spinal cord and the peripheral target organs. CONCLUSIONS: Spinal cord injury at sites remote from the lumbosacral spinal cord can indirectly influence properties of bladder afferent neurons by altering the function and chemical environment in the bladder or the spinal cord.  
  Call Number Serial 2147  
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Author (up) de Jong, A.; Dondorp, W.J.; Frints, S.G.M.; de Die-Smulders, C.E.M.; de Wert, G.M.W.R. file  url
  Title Advances in prenatal screening: the ethical dimension Type Journal Article
  Year 2011 Publication Nature Reviews. Genetics Abbreviated Journal Nat Rev Genet  
  Volume 12 Issue 9 Pages 657-663  
  Keywords Abortion, Eugenic; Aneuploidy; Child; *Chromosome Aberrations; Ethics, Medical; Female; Genetic Association Studies/*methods; Genetic Testing; Humans; Infant, Newborn; Karyotyping; Neonatal Screening/*ethics; Patient Rights/ethics; Pregnancy; Prenatal Diagnosis/ethics/methods; Sequence Analysis, DNA  
  Abstract Prenatal screening strategies are undergoing rapid changes owing to the introduction of new testing techniques. The overall tendency is towards broadening the scope of prenatal testing through increasingly sensitive ultrasound scans and genome-wide molecular tests. In addition, non-invasive prenatal diagnosis is likely to be introduced in the near future. These developments raise important ethical questions concerning meaningful reproductive choice, the autonomy rights of future children, equity of access and the proportionality of testing.  
  Call Number Serial 1356  
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Author (up) de Waal, F.B. file  url
  Title The organization of agonistic relations within two captive groups of Java-monkeys (Macaca fascicularis) Type Journal Article
  Year 1977 Publication Zeitschrift fur Tierpsychologie Abbreviated Journal Z Tierpsychol  
  Volume 44 Issue 3 Pages 225-282  
  Keywords Age Factors; Aggression; Animals; Behavior, Animal/*physiology; Competitive Behavior/*physiology; Fear; Female; Haplorhini; Humans; Macaca/*physiology; Macaca fascicularis/*physiology; Male; Sex Factors; Social Behavior; Social Dominance  
  Abstract The paper offers a detailed quantitative descripition of the distribution of agonistic activities over the members of two groups of Java-monkeys (Macaca fascicularis). These groups lived in captivity and were well-established: i.e. they had an extensive network of genealogical relationships. The study pays special attention to agonistic interactions with three or more participants. Its main purpose is an analysis of the way dyadic agonistic relations (e.g. dominance relations) are affected by third group members and the relations among these. The paper presents data on the ontogeny of 'dependent dominance', the 'control role' of the alpha-male, and the functions of different types of alliances.  
  Call Number Serial 126  
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Author (up) De, S. file  url
  Title Somatic mosaicism in healthy human tissues Type Journal Article
  Year 2011 Publication Trends in Genetics : TIG Abbreviated Journal Trends Genet  
  Volume 27 Issue 6 Pages 217-223  
  Keywords Aging; Animals; DNA, Mitochondrial/genetics; Humans; *Mosaicism; Mutation  
  Abstract From the fertilization of an egg until the death of an individual, somatic cells can accumulate genetic changes, such that cells from different tissues or even within the same tissue differ genetically. The presence of multiple cell clones with distinct genotypes in the same individual is referred to as 'somatic mosaicism'. Many endogenous factors such as mobile elements, DNA polymerase slippage, DNA double-strand break, inefficient DNA repair, unbalanced chromosomal segregation and some exogenous factors such as nicotine and UV exposure can contribute to the generation of somatic mutations, thereby leading to somatic mosaicism. Such changes can potentially affect the epigenetic patterns and levels of gene expression, and ultimately the phenotypes of cells. Although recent studies suggest that somatic mosaicism is widespread during normal development and aging, its implications for heightened disease risks are incompletely understood. Here, I discuss the origins, prevalence and implications of somatic mosaicism in healthy human tissues.  
  Call Number Serial 1775  
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Author (up) Dhib-Jalbut, S.; Marks, S. file  url
  Title Interferon-beta mechanisms of action in multiple sclerosis Type Journal Article
  Year 2010 Publication Neurology Abbreviated Journal Neurology  
  Volume 74 Suppl 1 Issue Pages S17-24  
  Keywords Animals; Antigen-Presenting Cells/*immunology; Cytokines/immunology; Humans; Immunity, Innate/*immunology; Immunologic Factors/*immunology; Interferon-beta/*immunology; *Models, Immunological; Multiple Sclerosis/*immunology; T-Lymphocytes/*immunology  
  Abstract ABSTRACT Multiple sclerosis (MS) is a chronic autoimmune disease of the CNS characterized by inflammation, demyelination, and axonal injury. These pathologic effects are manifested in clinical symptoms of relapse and disability. Various disease-modifying therapies have been developed in recent years to modulate the body's immune response. Among the most widely used are the beta interferons (IFNbeta). All produce comparable biological effects and are approved for the treatment of relapsing-remitting MS (RRMS). Although the precise mechanisms through which IFNbeta achieves its antiinflammatory and immunomodulatory effects remain uncertain, several modes of action have been proposed, including inhibition of T-cell activation and proliferation; apoptosis of autoreactive T cells; induction of regulatory T cells; inhibition of leukocyte migration across the blood-brain barrier; cytokine modulation; and potential antiviral activity. Endogenously produced IFNbeta in the injured brain is also now believed to contribute to mediation of antiinflammatory and regenerative effects. All these mechanisms are believed to underlie the therapeutic effect of IFNbeta in the treatment of RRMS.  
  Call Number Serial 1015  
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Author (up) Dilsaver, S.C.; Alessi, N.E. file  url
  Title Antipsychotic withdrawal symptoms: phenomenology and pathophysiology Type Journal Article
  Year 1988 Publication Acta Psychiatrica Scandinavica Abbreviated Journal Acta Psychiatr Scand  
  Volume 77 Issue 3 Pages 241-246  
  Keywords Antipsychotic Agents/*adverse effects; Brain/drug effects; Humans; Psychotic Disorders/*drug therapy; Receptors, Neurotransmitter/drug effects; Substance Withdrawal Syndrome/*physiopathology  
  Abstract The authors review the literature discribing non-dyskinetic antipsychotic withdrawal phenomena. Withdrawal of these agents can cause nausea, emesis, anorexia, diarrhea, rhinorrhea, diaphoresis, myalgia, paresthesia, anxiety, agitation, restlessness, and insomnia. Psychotic relapse is often presaged by increased anxiety, agitation, restlessness and insomnia, but the temporal relationship of these prodromal symptoms to reduction in the dosage or discontinuation of neuroleptics distinguishes them from the effects of abrupt withdrawal.  
  Call Number Serial 213  
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Author (up) Dimitrijevic, M.R.; Danner, S.M.; Mayr, W. file  url
  Title Neurocontrol of Movement in Humans With Spinal Cord Injury Type Journal Article
  Year 2015 Publication Artificial Organs Abbreviated Journal Artif Organs  
  Volume 39 Issue 10 Pages 823-833  
  Keywords Electric Stimulation Therapy; Humans; Motor Skills/physiology; Movement/*physiology; Spinal Cord/physiopathology; Spinal Cord Injuries/*physiopathology/therapy; Walking/physiology; Afferent inputs; Functional electrical stimulation; Motor control; Neurocontrol; Spinal cord injury  
  Abstract In this review of neurocontrol of movement after spinal cord injury, we discuss neurophysiological evidences of conducting and processing mechanisms of the spinal cord. We illustrate that external afferent inputs to the spinal cord below the level of the lesion can modify, initiate, and maintain execution of movement in absence or partial presence of brain motor control after chronic spinal cord injury. We review significant differences between spinal reflex activity elicited by single and repetitive stimulation. The spinal cord can respond with sensitization, habituation, and dis-habituation to regular repetitive stimulation. Therefore, repetitive spinal cord reflex activity can contribute to the functional configuration of the spinal network. Moreover, testing spinal reflex activity in individuals with motor complete spinal cord injury provided evidences for subclinical residual brain influence, suggesting the existence of axons traversing the injury site and influencing the activities below the level of lesion. Thus, there are two motor control models of chronic spinal cord injury in humans: “discomplete” and “reduced and altered volitional motor control.” We outline accomplishments in modification and initiation of altered neurocontrol in chronic spinal cord injury people with epidural and functional electrical stimulation. By nonpatterned electrical stimulation of lumbar posterior roots, it is possible to evoke bilateral extension as well as rhythmic motor outputs. Epidural stimulation during treadmill stepping shows increased and/or modified motor activity. Finally, volitional efforts can alter epidurally induced rhythmic activities in incomplete spinal cord injury. Overall, we highlight that upper motor neuron paralysis does not entail complete absence of connectivity between cortex, brain stem, and spinal motor cells, but there can be altered anatomy and corresponding neurophysiological characteristics. With specific input to the spinal cord below the level of the lesion, the clinical status of upper motor neuron paralysis without structural modification can be modified, and movements can be initiated. Thus, external afferent input can partially replace brain control.  
  Call Number Serial 2146  
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Author (up) Diringer, S.E.; Feingold, B.J.; Ortiz, E.J.; Gallis, J.A.; Araujo-Flores, J.M.; Berky, A.; Pan, W.K.Y.; Hsu-Kim, H. file  url
  Title River transport of mercury from artisanal and small-scale gold mining and risks for dietary mercury exposure in Madre de Dios, Peru Type Journal Article
  Year 2015 Publication Environmental Science. Processes & Impacts Abbreviated Journal Environ Sci Process Impacts  
  Volume 17 Issue 2 Pages 478-487  
  Keywords Animals; Diet; Environmental Exposure/*statistics & numerical data; Fishes/metabolism; Gold; Humans; Mercury/*analysis/metabolism; *Mining; Peru; Rivers/*chemistry; Water Pollutants, Chemical/*analysis/metabolism; Water Pollution, Chemical/statistics & numerical data  
  Abstract Artisanal and small-scale gold mining (ASGM) is a major contributor to deforestation and the largest anthropogenic source of atmospheric mercury worldwide. Despite significant information on the direct health impacts of mercury to ASGM miners, the impact of mercury contamination on downstream communities has not been well characterized, particularly in Peru's Madre de Dios region. In this area, ASGM has increased significantly since 2000 and has led to substantial political and social controversy. This research examined the spatial distribution and transport of mercury through the Madre de Dios River with distance from ASGM activity. This study also characterized risks for dietary mercury exposure to local residents who depend on fish from the river. River sediment, suspended solids from the water column, and fish samples were collected in 2013 at 62 sites near 17 communities over a 560 km stretch of the Madre de Dios River and its major tributaries. In areas downstream of known ASGM activity, mercury concentrations in sediment, suspended solids, and fish within the Madre de Dios River were elevated relative to locations upstream of mining. Fish tissue mercury concentrations were observed at levels representing a public health threat, with greater than one-third of carnivorous fish exceeding the international health standard of 0.5 mg kg(-1). This study demonstrates that communities located hundreds of kilometers downstream of ASGM activity, including children and indigenous populations who may not be involved in mining, are at risk of dietary mercury exposure that exceed acceptable body burdens. This report represents the first systematic study of the region to aid policy decision-making related to ASGM activities in Peru.  
  Call Number Serial 1528  
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Author (up) Dobson, S.D. file  url
  Title Are the differences between Stw 431 (Australopithecus africanus) and A.L. 288-1 (A. afarensis) significant? Type Journal Article
  Year 2005 Publication Journal of Human Evolution Abbreviated Journal J Hum Evol  
  Volume 49 Issue 1 Pages 143-154  
  Keywords Animals; Anthropology, Physical; Anthropometry; Biological Evolution; Body Constitution--physiology; Bone and Bones--anatomy & histology; Fossils; Hominidae--anatomy & histology; Humans; Joints--anatomy & histology; Pan troglodytes--anatomy & histology  
  Abstract Recent studies of early hominin body proportions paint a complex evolutionary picture, with multiple instances of reversal in body shape. These interpretations rest heavily upon the inferred limb joint proportions of Australopithecus africanus. For example, the partial skeleton Stw 431 has been suggested to show ape-like joint proportions compared to the A. afarensis specimen A.L. 288-1. This suggests an evolutionary reversal in the more recent A. africanus. However, no study has examined the probability of sampling the differences between Stw 431 and A.L. 288-1 from a single extant hominoid species. The present study compares elbow/hip and elbow/lumbosacral joint size ratios between Stw 431 and A.L. 288-1 using exact randomization, based on chimpanzee and human models of variation. Results indicate that differences in elbow/hip proportions between Stw 431 and A.L. 288-1 can be sampled from a single species. In contrast, differences in elbow/lumbosacral proportions between Stw 431 and A.L. 288-1 show a significantly low probability of being sampled from a single species. Thus, Stw 431 and A.L. 288-1 are not significantly different from each with regard to limb joint proportions, but Stw 431 has a significantly smaller lumbosacral joint. This pattern does not conform to previous interpretations of limb proportions in A. africanus. Low statistical power in the present study may account for the discrepancy. Further research is needed to illuminate the functional implications of variation in relative lumbosacral joint size in early hominins.  
  Call Number Serial 51  
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