Longitudinal Brain Size Measurements in App/Ps1 Transgenic Mice

2010 ◽  
Vol 4 ◽  
pp. MRI.S5885 ◽  
Author(s):  
Trevor J. Vincent ◽  
Jonathan D. Thiessen ◽  
Laryssa M. Kurjewicz ◽  
Shelley L. Germscheid ◽  
Allan J. Turner ◽  
...  
Keyword(s):  
Brain Size ◽  
Three Dimensional ◽  
Gene Mutations ◽  
Mutant Form ◽  
Swedish Mutation ◽  
Significant Difference ◽  
Lateral Width ◽  
Resolution Imaging ◽  
Or Gene ◽  
The Brain

There appear to be species differences among the effects of gene mutations related to familial Alzheimer's disease on the brain during aging. To gain a better understanding of the effects of the Swedish mutation of amyloid precursor protein and the mutant form of human presenilin 1 on mice, commercially available mice from Jackson Laboratory were studied. Three dimensional T2*-weighted imaging was used to monitor the size of brains of APP/PS1 mice monthly, from 6 to 13 months of age. No significant difference was measured in the size of the medial-lateral width, dorsal-ventral height, rostral-caudal length or the volume of the APPSwe/ PS1 mouse brain. Faster and higher-resolution imaging methods are needed to accurately determine if small volume or shape changes occur in mouse brains with age or gene mutations.

On the microstructural origin of brain white matter hydraulic permeability

2021 ◽  
Vol 118 (36) ◽  
pp. e2105328118
Author(s):  
Marco Vidotto ◽  
Andrea Bernardini ◽  
Marco Trovatelli ◽  
Elena De Momi ◽  
Daniele Dini
Keyword(s):  
White Matter ◽  
Corpus Callosum ◽  
Drug Transport ◽  
Three Dimensional ◽  
Principal Component ◽  
Hydraulic Permeability ◽  
Convection Enhanced Delivery ◽  
Brain White Matter ◽  
Significant Difference ◽  
The Brain

Brain microstructure plays a key role in driving the transport of drug molecules directly administered to the brain tissue, as in Convection-Enhanced Delivery procedures. The proposed research analyzes the hydraulic permeability of two white matter (WM) areas (corpus callosum and fornix) whose three-dimensional microstructure was reconstructed starting from the acquisition of electron microscopy images. We cut the two volumes with 20 equally spaced planes distributed along two perpendicular directions, and, on each plane, we computed the corresponding permeability vector. Then, we considered that the WM structure is mainly composed of elongated and parallel axons, and, using a principal component analysis, we defined two principal directions, parallel and perpendicular, with respect to the axons’ main direction. The latter were used to define a reference frame onto which the permeability vectors were projected to finally obtain the permeability along the parallel and perpendicular directions. The results show a statistically significant difference between parallel and perpendicular permeability, with a ratio of about two in both the WM structures analyzed, thus demonstrating their anisotropic behavior. Moreover, we find a significant difference between permeability in corpus callosum and fornix, which suggests that the WM heterogeneity should also be considered when modeling drug transport in the brain. Our findings, which demonstrate and quantify the anisotropic and heterogeneous character of the WM, represent a fundamental contribution not only for drug-delivery modeling, but also for shedding light on the interstitial transport mechanisms in the extracellular space.

scholarly journals Comparative brain analysis of wild and hatchery reared Mahseer (Tor putitora) relative to their body weight and length

2022 ◽  
Vol 82 ◽  
Author(s):  
N. Ullah ◽  
I. Ullah ◽  
M. Israr ◽  
A. Rasool ◽  
F. Akbar ◽  
...  
Keyword(s):  
Body Weight ◽  
Brain Size ◽  
Function Analysis ◽  
Analysis Of Covariance ◽  
Brain Morphology ◽  
Wild Stock ◽  
Significant Difference ◽  
Tor Putitora ◽  
Discriminate Function Analysis ◽  
The Brain

Abstract The present study was aimed at comparing the brain size of mahseer (Tor putitora) in relation to their body weight and standard length, to investigate the potential impact of rearing environment on brain development in fish. The weight of the brain and three of its subdivisions cerebellum (CB), optic tectum (OT), and telencephalon (TC) were measured for both wild and hatchery-reared fish. The data was analysed using multiple analysis of covariance (MANCOVA), analysis of covariance (ANCOVA), and discriminate function analysis (DFA). We found the fish reared under hatchery conditions exhibit smaller brain size related to body weight, when compared to the wild ones. A significant (p<0.5) difference was observed in the length of CB and OT concerning the standard body length while no significant difference was found in TC of the fish from both the origins. The results of the current study highlight a logical assumption that neural deficiency affects the behaviour of fish, that’s why the captive-reared fish show maladaptive response and face fitness decline when released to the natural environment for wild stock enhancement. The current study concluded that hatchery-reared fish exhibit variations in gross brain morphology as compared to their wild counterpart.

scholarly journals Neuroanatomical diversity of corpus callosum and brain volume in the Autism Brain Imaging Data Exchange (Abide) project

2014 ◽  
Author(s):  
Aline Lefebvre ◽  
Anita Beggiato ◽  
Thomas Bourgeron ◽  
Roberto Toro
Keyword(s):  
Corpus Callosum ◽  
Data Exchange ◽  
Brain Volume ◽  
Brain Size ◽  
Intracranial Volume ◽  
Long Distance ◽  
Significant Difference ◽  
Standard Deviations ◽  
Intelligence Scores ◽  
The Brain

The corpus callosum -- the main pathway for long-distance inter-hemispheric integration in the human brain -- has been frequently reported to be smaller among autistic patients compared with non-autistic controls. We conducted a meta-analysis of the literature which suggested a statistically significant difference. However, the studies included were heavily underpowered: on average only 20% power to detect differences of 0.3 standard deviations, which makes it difficult to establish the reality of such a difference. We therefore studied the size of the corpus callosum among 694 subjects (328 patients, 366 controls) from the Abide cohort. Despite having achieved 99% power to detect statistically significant differences of 0.3 standard deviations, we did not observe any. To better understand the neuroanatomical diversity of the corpus callosum, and the possible reasons for the previous findings, we analysed the relationship between its size, the size of the brain, intracranial volume and intelligence scores. The corpus callosum appeared to scale non-linearly with brain size, with large brains having a proportionally smaller corpus callosum. Additionally, intelligence scores correlated with brain volume among controls but the correlation was significantly weaker among patients. We used simulations to determine to which extent these two effects could lead to artefactual differences in corpus callosum size within populations. We observed that, were there a difference in brain volume between cases and controls, normalising corpus callosum size by brain volume would not eliminate the brain volume effect, but adding brain volume as a covariate in a linear model would. Finally, we observed that because of the weaker correlation of intelligence scores and brain volume among patients, matching populations by intelligence scores could result in a bias towards including more patients with large brain volumes, inducing an artificial difference. Overall, our results highlight the necessity for open data sharing efforts such as Abide to provide a more solid ground for the discovery of neuroimaging biomarkers, within the context of the wide human neuroanatomical diversity.

scholarly journals Comparison of diffusion-weighted imaging and enhanced T1-weighted sequencing in patients with multiple sclerosis

2017 ◽  
Vol 30 (4) ◽  
pp. 347-351 ◽  
Author(s):  
Amin Abolhasani Foroughi ◽  
Roohollah Salahi ◽  
Alireza Nikseresht ◽  
Hora Heidari ◽  
Masoume Nazeri ◽  
...  
Keyword(s):  
Multiple Sclerosis ◽  
Contrast Enhancement ◽  
Three Dimensional ◽  
Contrast Imaging ◽  
Technical Parameters ◽  
Flair Sequence ◽  
Significant Difference ◽  
Mri Protocol ◽  
Weighted Sequences ◽  
The Brain

Introduction The purpose of this study was to assess whether demographic, brain anatomical regions and contrast enhancement show differences in multiple sclerosis (MS) patients with increased diffusion lesions (ID group) compared with diffusion restriction (DR group). Method MRI protocol comprised T1- and T2-weighted sequences with and without gadolinium (Gd), and sagittal three-dimensional FLAIR sequence, DWI and ADC maps were prospectively performed in 126 MS patients from January to December 2015. The investigation was conducted to evaluate differences in demographic, cord and brain regional, technical, and positive or negative Gd contrast imaging parameters in two groups of ID and DR. Statistical analysis was performed by using SPSS. Results A total of 9.6% of patients showed DR. In the DR group, 66.6% of the patients showed contrast enhancement of plaques, whereas 29.2% of the IR group showed enhancement of plaques. The most prevalent group was non-enhanced plaques in the ID group, followed by Gd-enhanced plaques in the ID group. Patients in the ID group (90.4%) were significantly more than in the DR group (9.6%). Out of the 40 patients with Gd-enhanced plaques, 80.5% was from the ID group and 19.5% from the DR group. Conclusion MRI of the brain, unlike of the cord, with Gd demonstrates significant difference in enhancement between the two groups ( p < 0.05). No significant difference was seen in demographic, cord and brain regional, and technical parameters, EDSS, disease duration, and attack rate as well as demographic and regional parameters between the ID and decrease diffusion groups ( p > 0.05).

scholarly journals Variation in the strength of allometry drives rates of evolution in primate brain shape

2020 ◽  
Vol 287 (1930) ◽  
pp. 20200807 ◽  
Author(s):  
G. Sansalone ◽  
K. Allen ◽  
J. A. Ledogar ◽  
S. Ledogar ◽  
D. R. Mitchell ◽  
...  
Keyword(s):  
Brain Size ◽  
Three Dimensional ◽  
Shape Evolution ◽  
Evolutionary Time ◽  
Primate Brain ◽  
Rates Of Evolution ◽  
Evolutionary Allometry ◽  
The Relationship ◽  
The Brain ◽  
Brain Shape

Large brains are a defining feature of primates, as is a clear allometric trend between body mass and brain size. However, important questions on the macroevolution of brain shape in primates remain unanswered. Here we address two: (i), does the relationship between the brain size and its shape follow allometric trends and (ii), is this relationship consistent over evolutionary time? We employ three-dimensional geometric morphometrics and phylogenetic comparative methods to answer these questions, based on a large sample representing 151 species and most primate families. We found two distinct trends regarding the relationship between brain shape and brain size. Hominoidea and Cercopithecinae showed significant evolutionary allometry, whereas no allometric trends were discernible for Strepsirrhini, Colobinae or Platyrrhini. Furthermore, we found that in the taxa characterized by significant allometry, brain shape evolution accelerated, whereas for taxa in which such allometry was absent, the evolution of brain shape decelerated. We conclude that although primates in general are typically described as large-brained, strong allometric effects on brain shape are largely confined to the order's representatives that display more complex behavioural repertoires.

scholarly journals Evolution of the Human Brain: the key roles of DHA (omega-3 fatty acid) and Δ6-desaturase gene

OCL ◽  
2018 ◽  
Vol 25 (4) ◽  
pp. A401 ◽  
Author(s):  
Didier Majou
Keyword(s):  
Positive Selection ◽  
Homo Sapiens ◽  
Brain Size ◽  
Gene Mutations ◽  
Maximum Size ◽  
Omega 3 ◽  
Homo Neanderthalensis ◽  
Key Enzyme ◽  
The Brain ◽  
Δ6 Desaturase

The process of hominization involves an increase in brain size. The development of hominids’ cognitive capital up to the emergence ofHomo sapienswas due to interactive, iterative, and integrative coevolution, allowing positive selection. Although this depends on many factors, in this position paper we show three categories that stand out: gene mutations, food resources, and cognitive and behavioral stimulation.Australopithecusbenefited both from the inactivation of theGULOanduricasegenes and from bipedalism causing the cognitive capital of theHomo genus to develop advantageously. This evolution depended on two factors. Firstly, a triggering factor: gradual climate change.Homostarted to regularly consume meat in addition to plants and insects. Secondly, a stimulating factor: mutations in theFADS2gene, which encodes Δ6-desaturase; a key enzyme for the synthesis of DHA and sapienic acid. The polymorphism of this gene appears to have been essential in allowing theHomo genus to adapt to its food, and for its evolution. It provides an undeniable advantage in terms of the productivity of fat synthesis (DHA), and may partly explain positive selection. With the advent of cooking and new mutations producing even moreFADS2, the brain reached its maximum size inHomo neanderthalensis, in a food ecosystem that provided favorable quantities of α-Linolenic acid and DHA. However, the Würm glaciation upset this equilibrium, revealing its fragility as regards to the brain and fertility.Homo sapiens, benefiting from new variants of theFADS2gene, were able to adapt to this harsh environment, whereas Neanderthal man was unable to do so and became extinct.

Development of Mucoadhesive Buccal Drug Delivery System of Propranolol Hydrochloride Using Aster ericoides Mucilage

2020 ◽  
Vol 10 (2) ◽  
pp. 133-148
Author(s):  
Ankaj Kaundal ◽  
Pravin Kumar ◽  
Rajendra Awasthi ◽  
Giriraj T. Kulkarni
Keyword(s):  
Buccal Cavity ◽  
Three Dimensional ◽  
Hot Water ◽  
Fickian Diffusion ◽  
Aster Ericoides ◽  
Dimensional Network ◽  
Buccal Tablet ◽  
Significant Difference ◽  
Volunteer Group

Aim: The study was aimed to develop mucoadhesive buccal tablets using Aster ericoides leaves mucilage. Background : Mucilages are naturally occurring high-molecular-weight polyuronides, which have been extensively studied for their application in different pharmaceutical dosage forms. Objective: The objective of the present research was to establish the mucilage isolated from the leaves of Aster ericoides as an excipient for the formulation of the mucoadhesive buccal tablet. Method: The mucilage was isolated from the leaves of Aster ericoides by maceration, precipitated with acetone and characterized. Tablets were prepared using wet granulation technique and evaluated for various official tests. Results: The mucilage was found to be non-toxic on A-431 and Vero cell lines. It was insoluble but swellable in cold and hot water. The results indicate that mucilage can form a three-dimensional network. The pH of the mucilage (6.82 ± 0.13) indicated that it might be non-irritant to the buccal cavity. The mucilage was found to be free from microbes. The release of drug was by Fickian diffusion. The in vivo buccal tablet acceptance was 80%. No significant difference between the diastolic blood pressure of standard and Aster tablets treated volunteer group was recorded. Conclusion: The mucilage was found to be non-toxic on A-431 and Vero cell lines. It was insoluble but swellable in cold and hot water. The results indicate that mucilage can form a three-dimensional network. The pH of the mucilage (6.82 ± 0.13) indicated that it might be non-irritant to the buccal cavity. The mucilage was found to be free from microbes. The release of drug was by Fickian diffusion. The in vivo buccal tablet acceptance was 80%. No significant difference between the diastolic blood pressure of standard and Aster tablets treated volunteer group was recorded. Other: However, to prove the potency of the polymer, in vivo bioavailability studies in human volunteers are needed along with chronic toxicity studies in suitable animal models.

Bilateral Striatal Necrosis with Polyneuropathy with a Novel SLC25A19 (Mitochondrial Thiamine Pyrophosphate Carrier OMIMI*606521) Mutation: Treatable Thiamine Metabolic Disorder—A Report of Two Indian Cases

2019 ◽  
Vol 50 (05) ◽  
pp. 313-317 ◽  
Author(s):  
Vykuntaraju K. Gowda ◽  
Varunvenkat M. Srinivasan ◽  
Kapil Jehta ◽  
Maya D. Bhat
Keyword(s):  
Gene Mutations ◽  
Febrile Illness ◽  
Flaccid Paralysis ◽  
Thiamine Pyrophosphate ◽  
Homozygous Mutation ◽  
Missense Variation ◽  
Magnetic Resonance Imaging Mri ◽  
The Brain ◽  
Generation Sequencing ◽  
Striatal Necrosis

Abstract Background SLC25A19 gene mutations cause Amish congenital lethal microcephaly and bilateral striatal necrosis with polyneuropathy. We are reporting two cases of bilateral striatal necrosis with polyneuropathy due to SLC25A19 gene mutations. Methods A 36-month-old boy and a 5-year-old girl, unrelated, presented with recurrent episodes of flaccid paralysis and encephalopathy following nonspecific febrile illness. Examination showed dystonia and absent deep tendon reflexes. Results Nerve conduction studies showed an axonal polyneuropathy. Magnetic resonance imaging (MRI) of the brain in both cases showed signal changes in the basal ganglia. Next-generation sequencing revealed a novel homozygous missense variation c.910G>A (p.Glu304Lys) in the SLC25A19 gene in the boy and a homozygous mutation c.869T > A (p. Leu290Gln) in the SLC25A19 gene in the girl. Mutations were validated by Sanger sequencing, and carrier statuses of parents of both children were confirmed. Both children improved with thiamine supplementation. Conclusion If any child presents with recurrent encephalopathy with flaccid paralysis, dystonia, and neuropathy, a diagnosis of bilateral striatal necrosis with polyneuropathy due to SLC25A19 mutations should be considered and thiamine should be initiated.

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