scholarly journals Handedness in monkeys reflects hemispheric specialization within the central sulcus. An in vivo MRI study in right- and left-handed olive baboons

Cortex ◽  
2019 ◽  
Vol 118 ◽  
pp. 203-211 ◽  
Author(s):  
Konstantina Margiotoudi ◽  
Damien Marie ◽  
Nicolas Claidière ◽  
Olivier Coulon ◽  
Muriel Roth ◽  
...  
Keyword(s):  
Hemispheric Specialization ◽  
Central Sulcus ◽  
Olive Baboons ◽  
Left Handed ◽  
Mri Study

scholarly journals The sound of one-hand clapping: handedness and perisylvian neural correlates of a communicative gesture in chimpanzees

2012 ◽  
Vol 279 (1735) ◽  
pp. 1959-1966 ◽  
Author(s):  
Adrien Meguerditchian ◽  
Molly J. Gardner ◽  
Steven J. Schapiro ◽  
William D. Hopkins
Keyword(s):  
Hemispheric Specialization ◽  
Inferior Frontal Gyrus ◽  
Hand Preference ◽  
Planum Temporale ◽  
Brain Scans ◽  
Left Handed ◽  
The One ◽  
Language Areas ◽  
Research Facilities

Whether lateralization of communicative signalling in non-human primates might constitute prerequisites of hemispheric specialization for language is unclear. In the present study, we examined (i) hand preference for a communicative gesture (clapping in 94 captive chimpanzees from two research facilities) and (ii) the in vivo magnetic resonance imaging brain scans of 40 of these individuals. The preferred hand for clapping was defined as the one in the upper position when the two hands came together. Using computer manual tracing of regions of interest, we measured the neuroanatomical asymmetries for the homologues of key language areas, including the inferior frontal gyrus (IFG) and planum temporale (PT). When considering the entire sample, there was a predominance of right-handedness for clapping and the distribution of right- and left-handed individuals did not differ between the two facilities. The direction of hand preference (right- versus left-handed subjects) for clapping explained a significant portion of variability in asymmetries of the PT and IFG. The results are consistent with the view that gestural communication in the common ancestor may have been a precursor of language and its cerebral substrates in modern humans.

scholarly journals Functional topography of auditory areas derived from the combination of electrophysiological recordings and cortical electrical stimulation.

2021 ◽  
Author(s):  
Agnès Trébuchon ◽  
F.-Xavier Alario ◽  
Catherine Liégeois-Chauvel
Keyword(s):  
Language Processing ◽  
Hemispheric Specialization ◽  
Functional Characterization ◽  
Posterior Part ◽  
Epileptic Seizures ◽  
Superior Temporal Gyrus ◽  
Time Frequency ◽  
Depth Electrodes ◽  
Electrophysiological Recordings

The posterior part of the superior temporal gyrus (STG) has long been known to be a crucial hub for auditory and language processing, at the crossroad of the functionally defined ventral and dorsal pathways. Anatomical studies have shown that this “auditory cortex” is composed of several cytoarchitectonic areas whose limits do not consistently match macro-anatomic landmarks like gyral and sulcal borders. The functional characterization of these areas derived from brain imaging studies has some limitations, even when high field functional magnetic resonance imaging (fMRI) is used, because of the variability observed in the extension of these areas between hemispheres and individuals. In patients implanted with depth electrodes, in vivo recordings and direct electrical stimulations of the different sub-parts of the posterior STG allow to delineate different auditory sub-fields in Heschl’s gyrus (HG), Planum Temporale (PT), the posterior part of the superior temporal gyrus anterior to HG, the posterior superior temporal sulcus (STS), and the region at the parietal-temporal boundary commonly labelled “Spt”. We describe how this delineation can be achieved using data from electrical cortical stimulation combined with local field potentials and time frequency analysis recorded as responses to pure tones and syllables. We show the differences in functional roles between the primary and non-primary auditory areas, in the left and the right hemispheres. We discuss how these findings help understanding the auditory semiology of certain epileptic seizures and, more generally, the neural substrate of hemispheric specialization for language.

scholarly journals Assessment of Albumin ECM Accumulation and Inflammation as Novel In Vivo Diagnostic Targets for Multi-Target MR Imaging

Biology ◽  
2021 ◽  
Vol 10 (10) ◽  
pp. 964
Author(s):  
Jana Möckel ◽  
Julia Brangsch ◽  
Carolin Reimann ◽  
Jan O. Kaufmann ◽  
Ingolf Sack ◽  
...  
Keyword(s):  
Inductively Coupled Plasma ◽  
Endothelial Damage ◽  
Plaque Burden ◽  
Signal Loss ◽  
Inductively Coupled ◽  
Before And After ◽  
Plasma Mass Spectrometry ◽  
Magnetic Resonance Imaging Mri ◽  
Mri Study

Atherosclerosis is a progressive inflammatory vascular disease characterized by endothelial dysfunction and plaque burden. Extracellular matrix (ECM)-associated plasma proteins play an important role in disease development. Our magnetic resonance imaging (MRI) study investigates the feasibility of using two different molecular MRI probes for the simultaneous assessment of ECM-associated intraplaque albumin deposits caused by endothelial damage and progressive inflammation in atherosclerosis. Male apolipoprotein E-deficient (ApoE-/-)-mice were fed a high-fat diet (HFD) for 2 or 4 months. Another ApoE-/--group was treated with pravastatin and received a HFD for 4 months. T1- and T2*-weighted MRI was performed before and after albumin-specific MRI probe (gadofosveset) administration and a macrophage-specific contrast agent (ferumoxytol). Thereafter, laser ablation inductively coupled plasma mass spectrometry and histology were performed. With advancing atherosclerosis, albumin-based MRI signal enhancement and ferumoxytol-induced signal loss areas in T2*-weighted MRI increased. Significant correlations between contrast-to-noise-ratio (CNR) post-gadofosveset and albumin stain (R2 = 0.78, p < 0.05), and signal loss areas in T2*-weighted MRI with Perls’ Prussian blue stain (R2 = 0.83, p < 0.05) were observed. No interference of ferumoxytol with gadofosveset enhancement was detectable. Pravastatin led to decreased inflammation and intraplaque albumin. Multi-target MRI combining ferumoxytol and gadofosveset is a promising method to improve diagnosis and treatment monitoring in atherosclerosis.

Structures of major pilins in Clostridium perfringens demonstrate dynamic conformational change

2019 ◽  
Vol 75 (8) ◽  
pp. 718-732 ◽  
Author(s):  
Eiji Tamai ◽  
Seiichi Katayama ◽  
Hiroshi Sekiya ◽  
Hirofumi Nariya ◽  
Shigehiro Kamitori
Keyword(s):  
Conformational Change ◽  
Clostridium Perfringens ◽  
Bacterial Cell ◽  
Double Helix ◽  
Gram Positive Bacteria ◽  
Left Handed ◽  
Initial Adhesion ◽  
Practical Model ◽  
Host Tissues

Pili in Gram-positive bacteria are flexible rod proteins associated with the bacterial cell surface, and they play important roles in the initial adhesion to host tissues and colonization. The pilus shaft is formed by the covalent polymerization of major pilins, catalyzed by sortases, a family of cysteine transpeptidases. Here, X-ray structures of the major pilins from Clostridium perfringens strains 13 and SM101 and of sortase from strain SM101 are presented with biochemical analysis to detect the formation of pili in vivo. The major pilin from strain 13 adopts an elongated structure to form noncovalently linked polymeric chains in the crystal, yielding a practical model of the pilus fiber structure. The major pilin from strain SM101 adopts a novel bent structure and associates to form a left-handed twist like an antiparallel double helix in the crystal, which is likely to promote bacterial cell–cell interactions. A modeling study showed that pilin with a bent structure interacts favorably with sortase. The major pilin from strain SM101 was considered to be in an equilibrium state between an elongated and a bent structure through dynamic conformational change, which may be involved in pili-mediated colonization and sortase-mediated polymerization of pili.

Hemispheric Specialization in Normally and Slowly Developing Children: A Tachistoscopic and Dichaptic Evaluation

1980 ◽  
Vol 51 (3_suppl2) ◽  
pp. 1187-1201 ◽  
Author(s):  
H. G. Williams ◽  
V. A. Keough ◽  
J. M. Fisher ◽  
C. J. Seymour ◽  
M. G. Tanner
Keyword(s):  
Information Processing ◽  
Response Latency ◽  
Spatial Information ◽  
Hemispheric Specialization ◽  
Verbal Information ◽  
Considerable Evidence ◽  
Left Handed ◽  
Information Number

The purpose of the study was a description of hemispheric specialization characteristics of normally developing right- and left-handed children and determination of what differences in such characteristics, if any, existed between young normally developing and older slowly developing children. With dichaptic and tachistoscopic methods, hemispheric specialization characteristics of 15 slowly developing children (5-0 to 9-6 yr.) and 25 normally developing children (6-0 to 6-11 yr.) were assessed. Latencies and the number of correct responses were analyzed. Both right- and left-handed normally developing 6-yr.-olds showed considerable evidence of bilateralization of hemispheric functions for spatial and verbal information processing; slowly developing children exhibited unusual patterns of hemispheric specialization usually opposite those typically expected in children or adults. Response latency measures of performances of slowly developing children suggested a bilateralization of hemispheric function for processing of verbal and spatial information; number of correct responses indicated that lateralization of such functions was present.

Brain anatomy and ageing in non-demented adults with Down's syndrome: an in vivo MRI study

2009 ◽  
Vol 40 (4) ◽  
pp. 611-619 ◽  
Author(s):  
F. Beacher ◽  
E. Daly ◽  
A. Simmons ◽  
V. Prasher ◽  
R. Morris ◽  
...  
Keyword(s):  
Down's Syndrome ◽  
Down’S Syndrome ◽  
Brain Regions ◽  
Accelerated Ageing ◽  
Brain Anatomy ◽  
Parietal Lobes ◽  
Age Related ◽  
Brain Ageing ◽  
Mri Study

BackgroundPeople with Down's syndrome (DS) are at high risk for developing dementia in middle age. The biological basis for this is unknown. It has been proposed that non-demented adults with DS may undergo accelerated brain ageing.MethodWe used volumetric magnetic resonance imaging (MRI) and manual tracing to compare brain anatomy and ageing in 39 non-demented adults with DS and 42 healthy controls.ResultsIndividuals with DS had significant differences in brain anatomy. Furthermore, individuals with DS had a significantly greater age-related reduction in volume of frontal, temporal and parietal lobes, and a significantly greater age-related increase in volume of peripheral cerebrospinal fluid (CSF).ConclusionsNon-demented adults with DS have differences in brain anatomy and ‘accelerated’ ageing of some brain regions. This may increase their risk for age-related cognitive decline and Alzheimer's disease (AD).

scholarly journals Binding of Ferric Enterobactin by theEscherichia coli Periplasmic Protein FepB

2000 ◽  
Vol 182 (19) ◽  
pp. 5359-5364 ◽  
Author(s):  
Cathy Sprencel ◽  
Zhenghua Cao ◽  
Zengbiao Qi ◽  
Daniel C. Scott ◽  
Marjorie A. Montague ◽  
...  
Keyword(s):  
Specific Activity ◽  
Solid Phase ◽  
Cell Envelope ◽  
Binding Protein ◽  
Gel Filtration ◽  
Periplasmic Protein ◽  
Left Handed ◽  
Fluorescence Measurements ◽  
Rate Limiting Step

ABSTRACT The periplasmic protein FepB of Escherichia coli is a component of the ferric enterobactin transport system. We overexpressed and purified the binding protein 23-fold from periplasmic extracts by ammonium sulfate precipitation and chromatographic methods, with a yield of 20%, to a final specific activity of 15,500 pmol of ferric enterobactin bound/mg. Periplasmic fluid from cells overexpressing the binding protein adsorbed catecholate ferric siderophores with high affinity: in a gel filtration chromatography assay the Kd of the ferric enterobactin-FepB binding reaction was approximately 135 nM. Intrinsic fluorescence measurements of binding by the purified protein, which were more accurate, showed higher affinity for both ferric enterobactin (Kd = 30 nM) and ferric enantioenterobactin (Kd = 15 nM), the left-handed stereoisomer of the natural E. coli siderophore. Purified FepB also adsorbed the apo-siderophore, enterobactin, with comparable affinity (Kd = 60 nM) but did not bind ferric agrobactin. Polyclonal rabbit antisera and mouse monoclonal antibodies raised against nearly homogeneous preparations of FepB specifically recognized it in solid-phase immunoassays. These sera enabled the measurement of the FepB concentration in vivo when expressed from the chromosome (4,000 copies/cell) or from multicopy plasmids (>100,000 copies/cell). Overexpression of the binding protein did not enhance the overall affinity or rate of ferric enterobactin transport, supporting the conclusion that the rate-limiting step of ferric siderophore uptake through the cell envelope is passage through the outer membrane.

3D MENISCAL KINEMATICS DURING JOINT MOTION AND LOADING: A NOVEL IN-VIVO MRI STUDY OF THE KNEE

2012 ◽  
Vol 45 ◽  
pp. S369
Author(s):  
Daniel Watling ◽  
Gemma Whatling ◽  
Dr. Cathy Holt
Keyword(s):  
Joint Motion ◽  
Mri Study
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