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State effects and the effects of state building: institution building and the formation of state-centred societies

2016

AbstractThis article discusses the assumptions underlying state-building efforts and the effects of these efforts. It addresses two main questions: why has state building not led to the establishment of effective states? And what are the effects of statebuilding? It is argued that these efforts have been based on an institutionalist model of the state derived from a Weberian framework, and that the basic reason why state building has failed is that the creation of effective states requires the creation of state-centred societies, where both material and symbolic resources are concentrated in the state. This is very difficult to achieve for external actors. But, although state building has n…

Positive Controls in Adults and Children Support That Very Few, If Any, New Neurons Are Born in the Adult Human Hippocampus.

2020

Adult hippocampal neurogenesis was originally discovered in rodents. Subsequent studies identified the adult neural stem cells and found important links between adult neurogenesis and plasticity, behavior, and disease. However, whether new neurons are produced in the human dentate gyrus (DG) during healthy aging is still debated. We and others readily observe proliferating neural progenitors in the infant hippocampus near immature cells expressing doublecortin (DCX), but the number of such cells decreases in children and few, if any, are present in adults. Recent investigations using dual antigen retrieval find many cells stained by DCX antibodies in adult human DG. This has been interprete…

Human hippocampal neurogenesis drops sharply in children to undetectable levels in adults.

2018

New neurons continue to be generated in the subgranular zone of the dentate gyrus of the adult mammalian hippocampus(1-5). This process has been linked to learning and memory, stress and exercise, and is thought to be altered in neurological disease(6-10). In humans, some studies have suggested that hundreds of new neurons are added to the adult dentate gyrus every day(11), whereas other studies find many fewer putative new neurons(12-14). Despite these discrepancies, it is generally believed that the adult human hippocampus continues to generate new neurons. Here we show that a defined population of progenitor cells does not coalesce in the subgranular zone during human fetal or postnatal …

Rescuing Over-activated Microglia Restores Cognitive Performance in Juvenile Animals of the Dp(16) Mouse Model of Down Syndrome.

2020

Microglia are brain-resident immune cells and regulate mechanisms essential for cognitive functions. Down syndrome (DS), the most frequent cause of genetic intellectual disability, is caused by a supernumerary chromosome 21, containing also genes related to the immune system. In the hippocampus of the Dp(16) mouse model of DS and DS individuals, we found activated microglia, as assessed by their morphology; activation markers; and, for DS mice, electrophysiological profile. Accordingly, we found increased pro-inflammatory cytokine levels and altered interferon signaling in Dp(16) hippocampi. DS mice also showed decreased spine density and activity of hippocampal neurons and hippocampus-depe…

Microglia in Alzheimer’s Disease: Activated, Dysfunctional or Degenerative

2018

Microglial activation has been considered a crucial player in the pathological process of multiple human neurodegenerative diseases. In some of these pathologies, such as Amyotrophic Lateral Sclerosis or Multiple Sclerosis, the immune system and microglial cells (as part of the cerebral immunity) play a central role. In other degenerative processes, such as Alzheimer’s disease (AD), the role of microglia is far to be elucidated. In this “mini-review” article, we briefly highlight our recent data comparing the microglial response between amyloidogenic transgenic models, such as APP/PS1 and AD patients. Since the AD pathology could display regional heterogeneity, we focus our work at the hipp…

Differential Associations of IL-4 With Hippocampal Subfields in Mild Cognitive Impairment and Alzheimer’s Disease

2019

Background/Aims: A bi-directional communication between the immune system and the central nervous system has been recently suggested. Among many cytokines, the role of IL-4 - with anti-inflammatory properties- in counteracting age-related inflammatory changes in the brain is strongly supported among studies. With this study, we aimed at investigating the association between volumetric measures of hippocampal subregions -in healthy older controls (HC), subjects affected by mild cognitive impairment (MCI) and Alzheimer’s Disease (AD)- with circulating levels of IL-4. Methods: From AddNeuroMed Project 113 HC, 101 stable MCI (sMCI), 22 converter MCI (cMCI) and 119 AD were included. Hippocampal …

Clearing Amyloid-β Through PPARγ/ApoE Activation by Genistein is an Experimental Treatment of Alzheimer's Disease

2016

Amyloid-β (Aβ) clearance from brain, which is decreased in Alzheimer’s disease, is facilitated by apolipoprotein E. Apo E is up-regulated by activation of the retinoid X receptor moiety of the RXR/PPARγ dimeric receptor. Genistein, a non-toxic, well tested and inexpensive drug has a multifaceted protective effect: antioxidant (because it stimulates the expression of antioxidant genes), anit-inflammatory and stimulator of activates the PPARγ receptor, which results in increased expression of ApoE. Treatment of an Alzheimer’s mouse model with genistein results in a remarkable and rapid improvement in various parameters of cognition, such as hippocampal learning, recognition memory, implicit m…

2018

The bioactive coating of calcium phosphate cement (CPC) is a promising approach to enhance the bone-healing properties of bone substitutes. The purpose of this study was to evaluate whether coating CPCs with bone sialoprotein (BSP) results in increased bone formation. Forty-five female C57BL/6NRj mice with an average age of six weeks were divided into three groups. Either a BSP-coated or an uncoated three-dimensional plotted scaffold was implanted into a drilled 2.7-mm diameter calvarial defect, or the defect was left empty (control group; no CPC). Histological analyses revealed that BSP-coated scaffolds were better integrated into the local bone stock eight weeks after implantation. Bone v…

The Effects of Early Life Stress on the Brain and Behaviour: Insights From Zebrafish Models

2021

The early life period represents a window of increased vulnerability to stress, during which exposure can lead to long-lasting effects on brain structure and function. This stress-induced developmental programming may contribute to the behavioural changes observed in mental illness. In recent decades, rodent studies have significantly advanced our understanding of how early life stress (ELS) affects brain development and behaviour. These studies reveal that ELS has long-term consequences on the brain such as impairment of adult hippocampal neurogenesis, altering learning and memory. Despite such advances, several key questions remain inadequately answered, including a comprehensive overview…

Injectable Bone Substitute Based on β-TCP Combined With a Hyaluronan-Containing Hydrogel Contributes to Regeneration of a Critical Bone Size Defect T…

2015

In the present in vivo study, the regenerative potential of a new injectable bone substitute (IBS) composed of beta-tricalcium phosphate (β-TCP) and hyaluronan was tested in a rabbit distal femoral condyle model. To achieve this, 2 defects of 6 mm in diameter and 10 mm in length were drilled into each femur condyle in a total of 12 animals. For each animal, 1 hole was filled with the substitute material, and the other was left empty to serve as the control. After 1, 3, and 6 months, the regenerative process was analyzed by radiography as well as by histological and histomorphometrical analysis. The results revealed that bone tissue formation took place through osteoconductive processes over…