scholarly journals Individual variations of the human corticospinal tract and its hand-related motor fibers using diffusion MRI tractography

2018 ◽  
Author(s):  
Kyriakos Dalamagkas ◽  
Magdalini Tsintou ◽  
Yogesh Rathi ◽  
Lauren J O'Donnell ◽  
Ofer Pasternak ◽  
...  
Keyword(s):  
Diffusion Mri ◽  
Corticospinal Tract ◽  
Human Subjects ◽  
Biophysical Parameters ◽  
Motor Representation ◽  
Healthy Human ◽  
Disease States ◽  
Fiber Tracts ◽  
Cord Injury ◽  
Hand Motor Area

The corticospinal tract (CST) is one of the most well-studied tracts in human neuroanatomy. Its clinical significance can be demonstrated in many notable traumatic conditions and diseases such as stroke, spinal cord injury (SCI) or amyotrophic lateral sclerosis (ALS). With the advent of diffusion MRI and tractography the computational representation of the human CST in a 3D model became available. However, the representation of the entire CST and, specifically, the hand motor area has remained elusive. In this paper we proposed a novel method, using manually-drawn ROIs based on robustly identifiable neuroanatomic structures to delineate the entire CST and isolate its hand motor representation as well as to estimate their variability and generate a database of their volume, length and biophysical parameters. Using 37 healthy human subjects we performed a qualitative and quantitative analysis of the CST and the hand-related motor fiber tracts (HMFTs). Finally, we have created variability heatmaps from 37 subjects for both the aforementioned tracts, which could be utilized as reference for clinicians to explore neuropathology in both trauma and disease states.

Relevant Biophysical Parameters Discrimination along Corticospinal Tract in Patients with Stroke Using Convolutional Neural Networks

2021 ◽  
Vol 51 ◽  
pp. 95-103
Author(s):  
Abderrazek Zeraii ◽  
Amine Ben Slama ◽  
Lazhar Rmili ◽  
Cyrine Drissi ◽  
Mokhtar Mars ◽  
...  
Keyword(s):  
Motor Neurons ◽  
Corticospinal Tract ◽  
Diffusion Tensor ◽  
Biophysical Parameters ◽  
Spinal Motor Neurons ◽  
Fiber Tracts ◽  
Subacute Stroke ◽  
Quantitative Metrics ◽  
White Matter Fiber Tracts

Stroke remains the leading source of long-term disability. As the only direct descending motor pathway, the corticospinal tract (CST) is the primary pathway to innervate spinal motor neurons and one of the most well studied tracts in human neuroanatomy. Its clinical significance can be demonstrated in many distinguished traumatic situations and diseases such as stroke. Along‐tract statistics analysis enables the extraction of quantitative diffusion metrics along specific white matter fiber tracts. Besides quantitative metrics derived from classical diffusion tensor imaging (DTI), such as fractional anisotropy and diffusivities. In this study, we extracted DTI derived quantitative microstructural diffusion metrics along the CST tract in patients with moderate to severe subacute stroke. Respectively DTI metric of individual patient's fiber tract was then plotted. This approach may be useful for future studies that may compare in two different time (acute and chronic). The contribution of this work presents a totally computerized method of DTI image recognition based on conventional neural network (CNN) in order to supply quantitative appraisal of clinical characteristics. The obtained results have achieved an important classification (Accuracy=94.12%) when applying the CNN. The proposed methodology enables us to assess the classification of the used DTI images database within a reduced processing time. Experimental results prove the success of the proposed rating system for a suitable analysis of microstructural diffusion when compared to previous work.

scholarly journals Association betweenFaecalibacterium prausnitziiand dietary fibre in colonic fermentation in healthy human subjects

2010 ◽  
Vol 104 (5) ◽  
pp. 693-700 ◽  
Author(s):  
Robin F. J. Benus ◽  
Tjip S. van der Werf ◽  
Gjalt W. Welling ◽  
Patricia A. Judd ◽  
Moira A. Taylor ◽  
...  
Keyword(s):  
Intestinal Microbiota ◽  
Dietary Fibre ◽  
Human Subjects ◽  
Healthy Human ◽  
Formulated Diets ◽  
Disease States ◽  
Before And After ◽  
Complex Ecosystem ◽  
Positive Correlations ◽  
Proportional Reduction

The intestinal microbiota are a complex ecosystem influencing the immunoregulation of the human host, providing protection from colonising pathogens and producing SCFA as the main energy source of colonocytes. Our objective was to investigate the effect of dietary fibre exclusion and supplementation on the intestinal microbiota and SCFA concentrations. Faecal samples were obtained from healthy volunteers before and after two 14 d periods of consuming formulated diets devoid or supplemented with fibre (14 g/l). The faecal microbiota were analysed using fluorescentin situhybridisation and SCFA were measured using GLC. There were large and statistically significant reductions in the numbers of theFaecalibacterium prausnitzii(P ≤ 0·01) andRoseburiaspp. (P ≤ 0·01) groups during both the fibre-free and fibre-supplemented diets. Significant and strong positive correlations between the proportion ofF. prausnitziiand the proportion of butyrate during both baseline normal diets were found (pre-fibre freer0·881,P = 0·001; pre-fibre supplementedr0·844,P = 0·002). A significant correlation was also found between the proportional reduction inF. prausnitziiand the proportional reduction in faecal butyrate during both the fibre-free (r0·806;P = 0·005) and the fibre-supplemented diet (r0·749;P = 0·013). These findings may contribute to the understanding of the association between fibre, microbiota and fermentation in health, during enteral nutrition and in disease states such as Crohn's disease.

Minimizing Carry-Over Effects After Treatment Failure and Maximizing Therapeutic Outcome

2014 ◽  
Vol 222 (3) ◽  
pp. 171-178 ◽  
Author(s):  
Mareile Hofmann ◽  
Nathalie Wrobel ◽  
Simon Kessner ◽  
Ulrike Bingel
Keyword(s):  
Treatment Failure ◽  
Human Subjects ◽  
Subsequent Treatment ◽  
Clinical Samples ◽  
Administration Route ◽  
Healthy Human ◽  
Negative Experiences ◽  
Analgesic Treatment ◽  
Balanced Design ◽  
Carry Over

According to experimental and clinical evidence, the experiences of previous treatments are carried over to different therapeutic approaches and impair the outcome of subsequent treatments. In this behavioral pilot study we used a change in administration route to investigate whether the effect of prior treatment experience on a subsequent treatment depends on the similarity of both treatments. We experimentally induced positive or negative experiences with a topical analgesic treatment in two groups of healthy human subjects. Subsequently, we compared responses to a second, unrelated and systemic analgesic treatment between both the positive and negative group. We found that there was no difference in the analgesic response to the second treatment between the two groups. Our data indicate that a change in administration route might reduce the influence of treatment history and therefore be a way to reduce negative carry-over effects after treatment failure. Future studies will have to validate these findings in a fully balanced design including larger, clinical samples.

Detection of Soluble Fibrin Monomer Complexes in Blood by Means of Protamine Sulphate Test

1968 ◽  
Vol 20 (01/02) ◽  
pp. 044-049 ◽  
Author(s):  
B Lipiński ◽  
K Worowski
Keyword(s):  
Human Subjects ◽  
Coronary Thrombosis ◽  
Mean Value ◽  
Healthy Human ◽  
Protamine Sulphate ◽  
Soluble Fibrin ◽  
Fibrin Monomer ◽  
Dog Plasma ◽  
The Mean ◽  
Precipitable Protein

SummaryIn the present paper described is a simple test for detecting soluble fibrin monomer complexes (SFMC) in blood. The test consists in mixing 1% protamine sulphate with diluted oxalated plasma or serum and reading the optical density at 6190 Å. In experiments with dog plasma, enriched with soluble fibrin complexes, it was shown that OD read in PS test is proportional to the amount of fibrin recovered from the precipitate. It was found that SFMC level in plasma increases in rabbits infused intravenously with thrombin and decreases after injection of plasmin with streptokinase. In both cases PS precipitable protein in serum is elevated indicating enhanced fibrinolysis. In healthy human subjects the mean value of OD readings in plasma and sera were found to be 0.30 and 0.11, while in patients with coronary thrombosis they are 0.64 and 0.05 respectively. The origin of SFMC in circulation under physiological and pathological conditions is discussed.

Chronic stress decreases circulating endocannabinoid 2-arachidonoylglycerol in healthy human subjects

2015 ◽  
Author(s):  
Buqing Yi ◽  
Igor Nichiporuk ◽  
Matthias Feuerecker ◽  
Gustav Schelling ◽  
Alexander Chouker
Keyword(s):  
Chronic Stress ◽  
Human Subjects ◽  
Healthy Human ◽  
Healthy Human Subjects

Neuroserpin in Bipolar Disorder

2020 ◽  
Vol 20 (7) ◽  
pp. 518-523
Author(s):  
Rugül Köse Çinar
Keyword(s):  
Gene Expression ◽  
Bipolar Disorder ◽  
Polymerase Chain Reaction Method ◽  
Type I ◽  
Healthy Controls ◽  
Neuroprotective Effects ◽  
Expression Levels ◽  
Disease States ◽  
Cord Injury ◽  
System Functioning

Objective: Neuroserpin is a serine protease inhibitor predominantly expressed in the nervous system functioning mainly in neuronal migration and axonal growth. Neuroprotective effects of neuroserpin were shown in animal models of stroke, brain, and spinal cord injury. Postmortem studies confirmed the involvement of neuroserpin in Alzheimer’s disease. Since altered adult neurogenesis was postulated as an aetiological mechanism for bipolar disorder, the possible effect of neuroserpin gene expression in the disorder was evaluated. Methods: Neuroserpin mRNA expression levels were examined in the peripheral blood of bipolar disorder type I manic and euthymic patients and healthy controls using the polymerase chain reaction method. The sample comprised of 60 physically healthy, middle-aged men as participants who had no substance use disorder. Results: The gene expression levels of neuroserpin were found lower in the bipolar disorder patients than the healthy controls (p=0.000). The neuroserpin levels did not differ between mania and euthymia (both 96% down-regulated compared to the controls). Conclusion: Since we detected differences between the patients and the controls, not the disease states, the dysregulation in the neuroserpin gene could be interpreted as a result of the disease itself.

Sign in / Sign up

Export Citation Format

Share Document