scholarly journals Localisation in PET Images: Direct Fitting of the Intercommissural (AC—PC) Line

1989 ◽  
Vol 9 (5) ◽  
pp. 690-695 ◽  
Author(s):  
K. J. Friston ◽  
R. E. Passingham ◽  
J. G. Nutt ◽  
J. D. Heather ◽  
G. V. Sawle ◽  
...  

A technique is described for estimating the position of the intercommisural line (AC–PC line) directly from landmarks on positron emission tomographic (PET) images, namely the ventral aspects of the anterior and posterior corpus callosum, the thalamus, and occipital pole. The relationship of this estimate to the true AC–PC line, fitted through the centres of the anterior and posterior commissures, showed minimal vertical and angular displacement when measured on magnetic resonance imaging (MRI) scans. Using regression analysis, the ease and reliability of fitting to these points was found to be high. This directly derived AC–PC line estimate was validated in terms of the assumptions used in the method of Fox et al. The ratio of distance between the AC–PC line and a line passing through the base of the inion (GI line) to total brain height was 0.21, as predicted. The technique has been further validated by localizing focal activation of the sensorimotor cortex. The technique is discussed in terms of absolute limits to localization of structures in the brain using noninvasive tomographic techniques in general and PET in particular.

2017 ◽  
Vol 59 (3) ◽  
pp. 355-362 ◽  
Author(s):  
Supika Kritsaneepaiboon ◽  
Natee Ina ◽  
Thirachit Chotsampancharoen ◽  
Supaporn Roymanee ◽  
Sirichai Cheewatanakornkul

Background Cardiac and liver iron assessment using magnetic resonance imaging (MRI) is non-invasive and used as a preclinical “endpoint” in asymptomatic patients and for serial iron measurements in iron-overloaded patients. Purpose To compare iron measurements between hepatic and myocardial T2* and T2 at 1.5T and 3T MRI in normal and iron-overloaded patients. Material and Methods The T2 and T2* values from the regions of interest (ROIs) at mid-left ventricle and mid-hepatic slices were evaluated by 1.5T and 3T MRI scans for healthy and iron-overloaded patients. Results For iron-overloaded patients, the myocardial T2 (1.5T) and myocardial T2 (3T) values were 60.3 ms (range = 56.2–64.8 ms) and 55 ms (range = 51.6–60.1 ms) (ρ = 0.3679) while the myocardial T2* (3T) 20.5 ms (range = 18.4–25.9 ms) was shorter than the myocardial T2* (1.5T) 35.9 ms (range = 31.4–39.5 ms) (ρ = 0.6454). The hepatic T2 at 1.5T and 3T were 19.1 ms (range = 14.8–27.9 ms) and 15.5 ms (14.6–20.4 ms) (ρ = 0.9444) and the hepatic T2* at 1.5T and 3T were 2.7 ms (range = 1.8–5.6 ms) and 1.8 ms (range = 1.1–2.9 ms) (ρ = 0.9826). The line of best fit exhibiting the linearity of the hepatic T2* (1.5T) and hepatic T2* (3T) had a slope of 2 and an intercept of –0.387 ms (R = 0.984). Conclusion Our study found myocardial T2 (1.5T) nearly equal to T2 (3T) with myocardial T2* (3T) 1.75 shorter than myocardial T2* (1.5T). The relationship of hepatic T2* (1.5T) and hepatic T2* (3T) was linear with T2* (1.5T) approximately double to T2* (3T) in iron-overloaded patients. This linear relationship between hepatic T2* (1.5T) and hepatic T2 (3T) could be an alternative method for estimating liver iron concentration (LIC) from 3T.


2010 ◽  
Vol 23 (2) ◽  
pp. 264-273 ◽  
Author(s):  
Adrienne Withall ◽  
Henry Brodaty ◽  
Annette Altendorf ◽  
Perminder S. Sachdev

ABSTRACTBackground: There is growing recognition that apathy is not only a symptom of depression but may be an independent syndrome. This is the first study to investigate the relationship of apathy and depression longitudinally following stroke and to examine the association with dementia.Method: 106 consecutive eligible participants following stroke received extensive medical, psychiatric and neuropsychological assessments at three to six months (index assessment) and 15 months (follow-up assessment) after their stroke. A subset of participants received magnetic resonance imaging (MRI) scans at index assessment. Ratings were made for DSM-IV major or minor depression and for apathy using the Apathy Evaluation Scale (AES).Results: While there was no significant overlap between apathy and depression at index assessment (OR = 1.79, 95% CI 0.48, 6.66), the overlap was significant a year later (OR = 7.75, 95% CI 2.60, 23.13). Dementia at index assessment was a common risk factor for both apathy and depression at follow-up (OR = 12.45, 95% CI 2.98, 52.02 and OR = 10.35, 95% CI 2.84, 37.72, respectively).Conclusions: Apathy and depression after stroke have a common predictor and overlap longitudinally. The overlap might be due to cumulative vascular pathology and because of the relationship of each of these syndromes to dementia, which was an important, possibly causal, predictor for both.


2020 ◽  
Vol 21 (9) ◽  
pp. 649-660
Author(s):  
Subashini Raman ◽  
Syed Mahmood ◽  
Ayah R. Hilles ◽  
Md Noushad Javed ◽  
Motia Azmana ◽  
...  

Background: Blood-brain barrier (BBB) plays a most hindering role in drug delivery to the brain. Recent research comes out with the nanoparticles approach, is continuously working towards improving the delivery to the brain. Currently, polymeric nanoparticle is extensively involved in many therapies for spatial and temporal targeted areas delivery. Methods: We did a non-systematic review, and the literature was searched in Google, Science Direct and PubMed. An overview is provided for the formulation of polymeric nanoparticles using different methods, effect of surface modification on the nanoparticle properties with types of polymeric nanoparticles and preparation methods. An account of different nanomedicine employed with therapeutic agent to cross the BBB alone with biodistribution of the drugs. Results: We found that various types of polymeric nanoparticle systems are available and they prosper in delivering the therapeutic amount of the drug to the targeted area. The effect of physicochemical properties on nanoformulation includes change in their size, shape, elasticity, surface charge and hydrophobicity. Surface modification of polymers or nanocarriers is also vital in the formulation of nanoparticles to enhance targeting efficiency to the brain. Conclusion: More standardized methods for the preparation of nanoparticles and to assess the relationship of surface modification on drug delivery. While the preparation and its output like drug loading, particle size, and charge, permeation is always conflicted, so it requires more attention for the acceptance of nanoparticles for brain delivery.


2021 ◽  
Vol 190 ◽  
pp. 553-559
Author(s):  
Irina K. Malashenkova ◽  
Vadim L. Ushakov ◽  
Sergey A. Krynskiy ◽  
Daniil P. Ogurtsov ◽  
Nikita A. Khailov ◽  
...  

2021 ◽  
Vol 19 (2) ◽  
pp. 19-27
Author(s):  
A. V. DUBOVAYA ◽  
◽  
S. Ya. IAROSHENKO ◽  
O. A. PRILUTSKAYA ◽  
◽  
...  

The article discusses the influence of stress on the development of nervous tissue, in particular, on the synthesis of neurotrophins (by the example of the brain-derived neurotrophic factor (BDNF), as the most studied class representative). The biological functions of BDNF are discussed as well as its influence on neuroplasticity and the mechanisms by which the protection of neurons is carried out. The article covers the relationship of the stress-implementing system (hypothalamic-pituitary-adrenal axis) and its main active agent (cortisol) with the BDNF synthesis system at its various levels: from the inhibition of mRNA formation to the mechanisms of postsynaptic signal transmission. Information is also provided on changes of BDNF levels due to the maternal deprivation. Epigenetic changes under the influence of glucocorticoids are also reported. However, it is not only glucocorticoids that alter the functioning of the neurotrophin system. The article provides examples of the reverse effect, enabling to consider neurotrophins as a substance with an anti-stress function. In conclusion, the authors give examples of activities that, according to research, can stimulate the synthesis of neurotrophic factor in the brain.


2021 ◽  
Vol 3 (2) ◽  
Author(s):  
Roheela Yasmeen ◽  
Nida Mobeen ◽  
Muhammad Amjad Khan ◽  
Irfan Aslam ◽  
Samia Chaudhry

Epilepsy which is also called seizures disorder is an uncontrolled action of the central nervous system. Itis not a single disease but a set of neurological disorders. Actually in this situation, the brain does notreceive a precise signal and as a result an abnormal condition is produced that is usually involuntary inaction. In this review, we aimed to focus on the relationship of anti-epileptic drugs with sexual dysfunctionand adaptation of better remedies that improve a patient’s family life. Sexual dysfunction is a commoncomorbidity in people with epilepsy which badly affects their quality of life. Sexual dysfunction is causedby different factors like psychiatric problems, anti-epileptic drugs (AEDs) and social factors etc. Sexualdysfunctions include ejaculatory failure, lessen libido, penile erection in men and irregular menstrual cyclein women. Common drugs such as Topiramate, Gabapentin (GBP), Valproate (VA), Carbamazepine (CBZ),Olanzapine (OL) and Risperidone (RTG) that are in practice to treat epilepsy usually produced adverseeffect on sexual dysfunction. Even though a lot of studies have been carried out to control sexualdysfunction in epilepsy’s patient, but still research is going on. Medicine such as Cyproheptadine,Mianserin, Buspirone, Yohimbine were found better to treat epilepsy with minimum side effects of sexualdysfunction. Moreover, it is also seen that certain vasodilators, folate , and vitamin supplements areeffective in improving the quality of life.


Author(s):  
Luis Raul Meza Mendoza ◽  
María Elena Moya Martinez ◽  
Angelica Maria Sabando Suarez

Since the beginning of humanity, an attempt has been made to explain the way in which man acquires knowledge, the way in which he assimilates, processes and executes it in order to develop the teaching-learning process that people need throughout of his life, which forces to change the learning schemes using new study methodologies, such as neuroscience, which is a discipline that studies the functioning of the brain, the relationship of neurons to the formation of synapses creating immediate responses which transmits to the body voluntarily and involuntarily, in addition to controlling the central and peripheral nervous system with their respective functions. It is necessary to change the traditional scheme and implement new strategies that allow the teacher to venture into neuroscience, in order to individually understand the different learning processes that students do. As some authors of neuroscience say, the brain performs processes of acquisition, storage and evocation of information, which form new knowledge schemes that generate changes in the attitude of the human being, for this reason teachers are responsible for taking advantage of what It is known about the multiple functions of the brain and be clear about the various ways of acquiring knowledge.


2019 ◽  
Vol 4 (2) ◽  
pp. 114-129
Author(s):  
Hamam Burhanuddin

The study in this paper are explain about the studies of medical (medicine) blood type have the same relationship to human character because the blood producing antibodies and antigens. It could determine a person helpless hold strong or weak body, has an allergy to something or not, in the blood also contains various nutrients (like protein) and also the oxygen being supplied to the brain and nerves and body affect performance someone will then be emanated from the attitude of the person and social interaction. As has been explained, but keep in mind, there is blood in the genes, the nature of which is carried in the body/genotif rightly so it is, but we can not ignore the fenotif/nature arising or visible, this trait appear due to interaction between genes and the environment, so even if the person is smart in the intelligentsia and emotional, but grew up in a bad environment is going to be a bad trait. The theory of personality based on blood type can be used as a reference in parenting children through an understanding of the fundamental principles of the application of personality accompanied by parenting. Furthermore, the taking of steps in the care tailored to the stage of development of the child, in the Qur'an explicitly did not mentioned paragraph that discusses about blood type, but in the Qur'an there are blood (ad-Dam), Islamic studies in the study of Children is seen as a mandate from God, forming 3-dimensional relationships, with parents as the central figure. First, her parents relationship with God that is backed by the presence of children. Second, the relationship of the child (which still need a lot of guidance) with God through his parents. Third, the relationship of the child with both parents under the tutelage and guidance of God.


2016 ◽  
Vol 37 (3) ◽  
pp. 1095-1107 ◽  
Author(s):  
Jean-Dominique Gallezot ◽  
Beata Planeta ◽  
Nabeel Nabulsi ◽  
Donna Palumbo ◽  
Xiaoxi Li ◽  
...  

Measurements of drug occupancies using positron emission tomography (PET) can be biased if the radioligand concentration exceeds “tracer” levels. Negative bias would also arise in successive PET scans if clearance of the radioligand is slow, resulting in a carryover effect. We developed a method to (1) estimate the in vivo dissociation constant Kd of a radioligand from PET studies displaying a non-tracer carryover (NTCO) effect and (2) correct the NTCO bias in occupancy studies taking into account the plasma concentration of the radioligand and its in vivo Kd. This method was applied in a study of healthy human subjects with the histamine H3 receptor radioligand [11C]GSK189254 to measure the PK-occupancy relationship of the H3 antagonist PF-03654746. From three test/retest studies, [11C]GSK189254 Kd was estimated to be 9.5 ± 5.9 pM. Oral administration of 0.1 to 4 mg of PF-03654746 resulted in occupancy estimates of 71%–97% and 30%–93% at 3 and 24 h post-drug, respectively. NTCO correction adjusted the occupancy estimates by 0%–15%. Analysis of the relationship between corrected occupancies and PF-03654746 plasma levels indicated that PF-03654746 can fully occupy H3 binding sites ( ROmax = 100%), and its IC50 was estimated to be 0.144 ± 0.010 ng/mL. The uncorrected IC50 was 26% higher.


Part I. The Medulla Oblongata, And Its Variations Acoording To Diet And Feeding Habits In previous communications to this Society the relationship of the habits of feeding and diet to the form and pattern of the medulla oblongata has been described in the cyprinoids, clupeids, and gadoids (Evans, 1931, 1932, 1935). This research takes up a similar study of the brain of the Pleuronectidae. The expense has been borne by a grant from the Royal Society for which the author tenders his grateful thanks. It has seemed to be desirable to extend the observations to the fore- and mid-brain, as in some members of the family these present a very marked development. In order to elucidate some of the problems that arise I have also studied the brain of the eel, and some interesting conclusions have resulted. We find, as a result of examination by the naked eye and of serial sections, that we can divide the following species into four groups as follows: I. The sole, Solea vulgaris .


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