Ancylostoma caninum is a widely prevalent parasitic nematode in dogs across the world. There has been a notable increase in reports of anthelmintic resistance in A. caninum within the United States of America in recent years, which has led us to investigate the potential of this scenario in Canada.
View Article and Find Full Text PDFThe canine hookworm is one of the most prevalent parasitic nematodes in dogs worldwide and has the potential for zoonotic transmission to humans, including the development of cutaneous larva migrans. Recent confirmation of anthelmintic resistance (AR) in to several anthelmintic classes, mainly in the USA, indicates the potential for this scenario in Canada. We consider various factors that may lead to resistant isolates in Canada, such as the widespread use of antiparasitic drugs without the assessment of efficacy; increased prevalence in various Canadian provinces; and the importation of dogs, mostly from the USA, with a history of persistent infection by .
View Article and Find Full Text PDFUpper Normandy has several disadvantages in terms of access to dental health care for disabled people: an insufficient medical population, a lack of dental schools and dental care networks.A cross-sectional epidemiological investigation, using a questionnaire form, was carried out between November 2014 and February 2015 with a cohort of dentists in this region.The topics on this form focused firstly on accessibility and compliance with standards of dental offices and the influencing factors which are hampering their accessibility implementation, and secondly on the oral care of disabled patients by practitioners of this region : the impact of incentives, influencing factors which are complicating the dental care and the usage of private and public structures.
View Article and Find Full Text PDFDown syndrome (DS), caused by trisomy 21, is the most common genetic cause of intellectual disability and is associated with a greatly increased risk of early-onset Alzheimer's disease (AD). The Ts65Dn mouse model of DS exhibits several key features of the disease including developmental delay and AD-like cognitive impairment. Accumulating evidence suggests that impairments in early brain development caused by trisomy 21 contribute significantly to memory deficits in adult life in DS.
View Article and Find Full Text PDFBackground: The recent spread of positron emission tomography-computed tomography (PET/CT) poses extremity dosimetry challenges. The question arose whether the radiation dose measured by the ring thermoluminescent dosimeter usually worn on the proximal phalanx (P1) of the index finger measures doses that are representative of the true doses received by the upper extremities of the operators. A prospective individual dosimetry study was performed in which the personal equivalent dose Hp (0.
View Article and Find Full Text PDFDeficiency of protein phosphatase-2A is a key event in Alzheimer's disease. An endogenous inhibitor of protein phosphatase-2A, inhibitor-1, I1PP2A, which inhibits the phosphatase activity by interacting with its catalytic subunit protein phosphatase-2Ac, is known to be upregulated in Alzheimer's disease brain. In the present study, we overexpressed I1PP2A by intracerebroventricular injection with adeno-associated virus vector-1-I1PP2A in Wistar rats.
View Article and Find Full Text PDFAutism is a neurodevelopmental disorder characterized clinically by impairments in social interaction and verbal and non-verbal communication skills as well as restricted interests and repetitive behavior. It has been hypothesized that altered brain environment including an imbalance in neurotrophic support during early development contributes to the pathophysiology of autism. Here we report that sera from children with autism which exhibited abnormal levels of various neurotrophic factors induced cell death and oxidative stress in mouse primary cultured cortical neurons.
View Article and Find Full Text PDFProtein phosphatase-2A (PP2A) deficiency is a cause of the abnormal hyperphosphorylation of tau, which composes neurofibrillary tangles (NFTs) in Alzheimer's disease (AD) brain. We previously reported that both mRNA and protein expression of inhibitor I of PP2A (I(1)(PP2A)) are elevated in AD brain and that this inhibitor induces a dose-dependent inhibition of PP2A activity and tau hyperphosphorylation in NIH3T3 cells. However, whether I(1)(PP2A) can induce AD neurofibrillary degeneration and cognitive impairment was not known.
View Article and Find Full Text PDFSporadic Alzheimer's disease (AD) is a multifactorial metabolic brain disorder characterized by progressive neurodegeneration. Decreased brain energy and glucose metabolism occurs before the appearance of AD symptoms and worsens while the disease progresses. Deregulated brain insulin signaling has also been found in AD recently.
View Article and Find Full Text PDFBesides the presence of amyloid beta (Aβ) plaques and neurofibrillary tangles, neurogenesis and synaptic plasticity are markedly impaired in Alzheimer's disease (AD) possibly contributing to cognitive impairment. In this context, neurotrophic factors serve as a promising therapeutic approach via utilization of regenerative capacity of brain to shift the balance from neurodegeneration to neural regeneration. However, besides more conventional "bystander" effect, to what extent can neurotrophic compounds affect underlying AD pathology remains questionable.
View Article and Find Full Text PDFA minor component of coffee unrelated to caffeine, eicosanoyl-5-hydroxytryptamide (EHT), provides protection in a rat model for Alzheimer's disease (AD). In this model, viral expression of the phosphoprotein phosphatase 2A (PP2A) endogenous inhibitor, the I2(PP2A), or SET protein in the brains of rats leads to several characteristic features of AD including cognitive impairment, tau hyperphosphorylation, and elevated levels of cytoplasmic amyloid-β protein. Dietary supplementation with EHT for 6-12 months resulted in substantial amelioration of all these defects.
View Article and Find Full Text PDFThe etiopathogenesis of neither the sporadic form of Alzheimer disease (AD) nor of amyotrophic lateral sclerosis (ALS) is well understood. The activity of protein phosphatase-2A (PP2A), which regulates the phosphorylation of tau and neurofilaments, is negatively regulated by the myeloid leukemia-associated protein SET, also known as inhibitor-2 of PP2A, I2(PP2A). In AD brain, PP2A activity is compromised, probably because I2(PP2A) is overexpressed and is selectively cleaved at asparagine 175 into an N-terminal fragment, I2NTF, and a C-terminal fragment, I2CTF, and both fragments inhibit PP2A.
View Article and Find Full Text PDFAlzheimer's disease (AD) involves several possible molecular mechanisms, including impaired brain insulin signaling and glucose metabolism. To investigate the role of metabolic insults in AD, we injected streptozotocin (STZ), a diabetogenic compound if used in the periphery, into the lateral ventricle of the 6-month-old 3xTg-AD mice and studied the cognitive function as well as AD-like brain abnormalities, such as tau phosphorylation and Aβ accumulation, 3-6 weeks later. We found that STZ exacerbated impairment of short-term and spatial reference memory in 3xTg-AD mice.
View Article and Find Full Text PDFAlzheimer's disease is multifactorial and involves several different mechanisms. The sporadic form of the disease accounts for over 99% of the cases. As of yet, there is no practical and widely available animal model of the sporadic form of the disease.
View Article and Find Full Text PDFAlzheimer's disease (AD) can be divided into sporadic AD (SAD) and familial AD (FAD). Most AD cases are sporadic and result from multiple etiologic factors, including environmental, genetic, and metabolic factors, whereas FAD is caused by mutations in the presenilins or amyloid-β (Aβ) precursor protein (APP) genes. A commonly used animal model for AD is the 3xTg-AD transgenic mouse model, which harbors mutated presenilin 1, APP, and tau genes and thus represents a model of FAD.
View Article and Find Full Text PDFAlzheimer's disease (AD) is multifactorial and, to date, no single cause of the sporadic form of this disease, which accounts for over 99% of the cases, has been established. In AD brain, protein phosphatase-2A (PP2A) activity is known to be compromised due to the cleavage and translocation of its potent endogenous inhibitor, I2PP2A, from the neuronal nucleus to the cytoplasm. Here, we show that adeno-associated virus vector-induced expression of the N-terminal I2NTF and C-terminal I2CTF halves of I2PP2A , also called SET, in brain reproduced key features of AD in Wistar rats.
View Article and Find Full Text PDFDown syndrome (DS) is caused by the triplication of ∼240 protein-coding genes on chromosome 21 and is the most prevalent form of developmental disability. This condition results in abnormalities in many organ systems, as well as in intellectual retardation. Many previous efforts to understand brain dysfunction in DS have indicated that cognitive deficits are coincident with reduced synaptic plasticity and decreased neuronal proliferation.
View Article and Find Full Text PDFAdult neurogenesis, the production of new neurons in certain brain regions, is known to decrease with age and the loss of neurogenic potential has been implicated in Alzheimer's disease (AD), a leading cause of dementia in the elderly. Cerebrolysin (CBL) has been shown to increase neurogenesis in models of stroke and AD. CBL is composed of small peptides with activity similar to neurotrophic factors including ciliary neurotrophic factor (CNTF), which may mediate its neurogenic effects.
View Article and Find Full Text PDFDespite huge advances on Alzheimer's disease (AD) etiology, the clinical diagnosis remains the unique commonly used tool to detect the onset of the disease. For instance, epidemiological studies report that the combination of episodic and working memory disorders represents the most consistent sign of progression from mild cognitive impairment to AD. However, such working memory disorders failed to be observed early in transgenic mouse models of AD because the behavioral procedures used do not tackle properly crucial components of working memory.
View Article and Find Full Text PDFA therapeutic strategy against cognitive disorders like Alzheimer's disease is to take advantage of the regenerative ability of the brain and the properties of neurotrophic factors to shift the balance from neurodegeneration to neurogenesis and neuronal plasticity. Although the ciliary neurotrophic factor (CNTF) has some of the required neuroprotective characteristics, its clinical use, due to its side effects, i.e.
View Article and Find Full Text PDFIn addition to the occurrence of numerous neurofibrillary tangles and Aβ plaques, neurogenesis and neuronal plasticity are markedly altered in Alzheimer disease (AD). Although the most popular therapeutic approach has been to inhibit neurodegeneration, another is to promote neurogenesis and neuronal plasticity by utilizing the regenerative capacity of the brain. Here we show that, in a transgenic mouse model of AD, 3xTg-AD mice, there was a marked deficit in neurogenesis and neuroplasticity, which occurred before the formation of any neurofibrillary tangles or Aβ plaques and was associated with cognitive impairment.
View Article and Find Full Text PDFIndependent of the aetiology, AD (Alzheimer's disease) neurofibrillary degeneration of abnormally hyperphosphorylated tau, a hallmark of AD and related tauopathies, is apparently required for the clinical expression of the disease and hence is a major therapeutic target for drug development. However, AD is multifactorial and heterogeneous and probably involves several different aetiopathogenic mechanisms. On the basis of CSF (cerebrospinal fluid) levels of Abeta(1-42) (where Abeta is amyloid beta-peptide), tau and ubiquitin, five different subgroups, each with its own clinical profile, have been identified.
View Article and Find Full Text PDFDevelopment of rational therapeutic treatments of Alzheimer disease (AD) requires the elucidation of the etiopathogenic mechanisms of neurofibrillary degeneration and β-amyloidosis, the two hallmarks of this disease. Here we show, employing an adeno-associated virus serotype 1 (AAV1)-induced expression of the C-terminal fragment (I(2CTF)) of I(2)(PP2A), also called SET, in rat brain, decrease in protein phosphatase 2A (PP2A) activity, abnormal hyperphosphorylation of tau, and neurodegeneration; littermates treated identically but with vector only, i.e.
View Article and Find Full Text PDFDevelopment of neurotrophic peptidergic drugs that can mimic neurotrophins and promote neurogenesis and maturation of newborn cells into mature functional neurons represents an exciting therapeutic opportunity for treatment of Alzheimer disease and other learning and memory disorders as well as enhancing cognition of normal individuals. Here we report the design of a peptidergic compound, Ac-DGGLAG-NH2, called P21, when administered peripherally, enhanced learning as well as both short-term and spatial reference memories of normal adult C57Bl6 mice. P21 induced enhancement of neurogenesis and maturation of newly born neurons in the granular cell layer and subgranular zone of the dentate gyrus.
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