DNA methyltransferase 1 (DNMT1) is the enzyme primarily responsible for propagation of the methylation pattern in cells. Mutations in DNMT1 have been linked to the development of adult-onset neurodegenerative disorders; these disease-associated mutations occur in the regulatory replication foci-targeting sequence (RFTS) domain of the protein. The RFTS domain is an endogenous inhibitor of DNMT1 activity that binds to the active site and prevents DNA binding.
View Article and Find Full Text PDFDNA methylation, a form of epigenetic gene regulation, is important for normal cellular function. In cells, proteins called DNA methyltransferases (DNMTs) establish and maintain the DNA methylation pattern. Changes to the normal DNA methylation pattern are linked to cancer development and progression, making DNMTs potential cancer drug targets.
View Article and Find Full Text PDFHeterozygous mutations in the GBA1 gene - encoding lysosomal glucocerebrosidase (GCase) - are the most common genetic risk factors for Parkinson's disease (PD). Experimental evidence suggests a correlation between decreased GCase activity and accumulation of alpha-synuclein (aSyn). To enable a better understanding of the relationship between aSyn and GCase activity, we developed and characterized two mouse models that investigate aSyn pathology in the context of reduced GCase activity.
View Article and Find Full Text PDFMultiple mutations have been described in the human GBA1 gene, which encodes the lysosomal enzyme beta-glucocerebrosidase (GCase) that degrades glucosylceramide and is pivotal in glycosphingolipid substrate metabolism. Depletion of GCase, typically by homozygous mutations in GBA1, is linked to the lysosomal storage disorder Gaucher's disease (GD) and distinct or heterozygous mutations in GBA1 are associated with increased Parkinson's disease (PD) risk. While numerous genes have been linked to heritable PD, GBA1 mutations in aggregate are the single greatest risk factor for development of idiopathic PD.
View Article and Find Full Text PDFVisual system toxicity may manifest anywhere in the visual system, from the eye proper to the visual brain. Therefore, effective screening for visual system toxicity must evaluate not only ocular structures (ie, eye and optic nerve) but also multiple key brain regions involved in vision (eg, optic tract, subcortical relay nuclei, and primary and secondary visual cortices). Despite a generally comparable pattern across species, the neuroanatomic organization and function of the visual brain in rodents and rabbits exhibit appreciable differences relative to nonrodents.
View Article and Find Full Text PDFBackground: Various stains have been devised to reveal degenerative or reactive cell phenotypes, or the disintegrative and/or neuropathic lesions associated with Alzheimer's, Parkinson's, and Pick's diseases, Down's syndrome, or chemical toxicity. Utilization of silver staining has allowed researchers to elucidate neural pathways promoting a greater understanding of the functional connections between brain regions. All of these methods employing silver can be characterized as 'directed staining technologies'.
View Article and Find Full Text PDFIn eukaryotes, the most common epigenetic DNA modification is methylation of carbon 5 of cytosines, predominantly in CpG dinucleotides. Methylation patterns are established and maintained by a family of proteins known as DNA methyltransferases (DNMTs). DNA methylation is an important epigenetic mark associated with gene repression, and disruption of the normal DNA methylation pattern is known to play a role in several disease states.
View Article and Find Full Text PDFIn humans, the most common epigenetic DNA modification is methylation of the 5-carbon of cytosines, predominantly in CpG dinucleotides. DNA methylation is an important epigenetic mark associated with gene repression. Disruption of the normal DNA methylation pattern is known to play a role in the initiation and progression of many cancers.
View Article and Find Full Text PDFBackground: Over the past 10 years, three new MD schools have been created in the state of Michigan, while the Michigan State University College of Human Medicine (MSU-CHM) has increased their class size to 850 students. The aim of this study was to determine if MSU-CHM alumni who graduate from an MSU-affiliated primary care residency from a single graduate medical education (GME) training program in Michigan are more likely to go on to practice in close proximity to the location of their training program immediately after graduation compared to non MSU-CHM alumni. Changes over time in the proportion of primary care graduates who received fellowship training immediately following residency were also compared between these groups.
View Article and Find Full Text PDFBackground And Purpose: The potential for therapeutic antibody treatment of neurological diseases is limited by poor penetration across the blood-brain barrier. I.c.
View Article and Find Full Text PDFImportance: Switching between generic antiepileptic drugs is a highly debated issue that affects both clinical care and overall health care costs.
Objective: To evaluate the single-dose pharmacokinetic bioequivalence of 3 (1 branded and 2 generic drugs) on-market, immediate-release lamotrigine drug products.
Design, Setting, And Participants: The Equivalence Among Antiepileptic Drug Generic and Brand Products in People With Epilepsy (EQUIGEN) single-dose study is a crossover, prospective, sequence-randomized, replicate pharmacokinetic study conducted at 5 US academic epilepsy centers.
Proc SPIE Int Soc Opt Eng
August 2016
The Advanced Topographic Laser Altimeter System (ATLAS) Instrument has been in integration and testing over the past 18 months in preparation for the Ice, Cloud and Land Elevation Satellite - 2 (ICESat-2) Mission, scheduled to launch in 2017. ICESat-2 is the follow on to ICESat which launched in 2003 and operated until 2009. ATLAS will measure the elevation of ice sheets, glaciers and sea ice or the "cryosphere" (as well as terrain) to provide data for assessing the earth's global climate changes.
View Article and Find Full Text PDFMultiple sclerosis (MS) causes demyelinating lesions in the white matter and increased iron deposition in the subcortical gray matter. Myelin protons have an extremely short T2* (<1ms) and are not directly detected with conventional clinical magnetic resonance (MR) imaging sequences. Iron deposition also reduces T2*, leading to reduced signal on clinical sequences.
View Article and Find Full Text PDFPhosphoribosyl diphosphate (PRPP) is an important intermediate in cellular metabolism. PRPP is synthesized by PRPP synthase, as follows: ribose 5-phosphate + ATP → PRPP + AMP. PRPP is ubiquitously found in living organisms and is used in substitution reactions with the formation of glycosidic bonds.
View Article and Find Full Text PDFWe used controlled cortical impact in mice to model human traumatic brain injury (TBI). Local injury was accompanied by distal diaschisis lesions that developed within brain regions anatomically connected to the injured cortex. At 7 days after injury, histochemistry documented broadly distributed lesions, particularly in the contralateral cortex and ipsilateral thalamus and striatum.
View Article and Find Full Text PDFOnly a handful of bird species are known to use foraging tools in the wild. Amongst them, the New Caledonian crow (Corvus moneduloides) stands out with its sophisticated tool-making skills. Despite considerable speculation, the evolutionary origins of this species' remarkable tool behaviour remain largely unknown, not least because no naturally tool-using congeners have yet been identified that would enable informative comparisons.
View Article and Find Full Text PDFRecessively inherited loss-of-function mutations in the PTEN-induced putative kinase 1(Pink1), DJ-1 (Park7) and Parkin (Park2) genes are linked to familial cases of early-onset Parkinson's disease (PD). As part of its strategy to provide more tools for the research community, The Michael J. Fox Foundation for Parkinson's Research (MJFF) funded the generation of novel rat models with targeted disruption ofPink1, DJ-1 or Parkin genes and determined if the loss of these proteins would result in a progressive PD-like phenotype.
View Article and Find Full Text PDFNeurological dysfunction is common in humans and animals with lysosomal storage diseases. β-Mannosidosis, an autosomal recessive inherited disorder of glycoprotein catabolism caused by deficiency of the lysosomal enzyme β-mannosidase, is characterized by intracellular accumulation of small oligosaccharides in selected cell types. In ruminants, clinical manifestation is severe, and neuropathology includes extensive intracellular vacuolation and dysmyelination.
View Article and Find Full Text PDFBackground: High-grade appendiceal adenocarcinoma is a rare malignancy with propensity for peritoneal metastases (PM). The impact of neoadjuvant chemotherapy on operative cytoreduction (CRS) and intraperitoneal chemotherapy (HIPEC) and patient survival was reviewed.
Methods: A total of 45 patients with PM from high-grade appendiceal adenocarcinoma were identified from a prospective database.
We evaluated the acute (up to 24 h) pathophysiological response to primary blast using a rat model and helium driven shock tube. The shock tube generates animal loadings with controlled pure primary blast parameters over a wide range and field-relevant conditions. We studied the biomechanical loading with a set of pressure gauges mounted on the surface of the nose, in the cranial space, and in the thoracic cavity of cadaver rats.
View Article and Find Full Text PDFSpecies loss can lead to cascading effects on communities, including the disruption of ecological processes such as seed dispersal. The endangered 'Alalā (Corvus hawaiiensis), the largest remaining species of native Hawaiian forest bird, was once common in mesic and dry forests on the Big Island of Hawai'i, but today it exists solely in captivity. Prior to its extinction in the wild, the 'Alalā may have helped to establish and maintain native Hawaiian forest communities by dispersing seeds of a wide variety of native plants.
View Article and Find Full Text PDFElectrophysiological and behavioral studies have demonstrated that muscimol administered through the cranial meninges can prevent focal neocortical seizures. It was proposed that transmeningeal muscimol delivery can be used for the treatment of intractable focal neocortical epilepsy. However, it has not been proved that muscimol administered via the transmeningeal route can penetrate into the neocortex.
View Article and Find Full Text PDFBlast-induced traumatic brain injury (TBI) is the signature insult in combat casualty care. Survival with neurological damage from otherwise lethal blast exposures has become possible with body armor use. We characterized the neuropathologic alterations produced by a single blast exposure in rats using a helium-driven shock tube to generate a nominal exposure of 35 pounds per square inch (PSI) (positive phase duration ∼ 4 msec).
View Article and Find Full Text PDFMany new therapeutics for Alzheimer's disease delay the accumulation of amyloid-β (Aβ) in transgenic mice, but evidence for clearance of preexisting plaques is often lacking. Here, we demonstrate that anti-Aβ immunotherapy combined with suppression of Aβ synthesis allows significant removal of antecedent deposits. We treated amyloid-bearing tet-off APP (amyloid precursor protein) mice with doxycycline to suppress transgenic Aβ production before initiating a 12 week course of passive immunization.
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