scholarly journals Effect of Motion Contrast on Human Cortical Responses to Moving Stimuli

1998 ◽  
Vol 79 (5) ◽  
pp. 2794-2803 ◽  
Author(s):  
Gordon L. Shulman ◽  
Jacob Schwarz ◽  
Francis M. Miezin ◽  
Steven E. Petersen
Keyword(s):  
Superior Temporal Sulcus ◽  
Square Wave ◽  
Moving Stimuli ◽  
Positron Emission ◽  
Motion Condition ◽  
Collateral Sulcus ◽  
Cortical Responses ◽  
Motion Contrast ◽  
The Right ◽  
Unidirectional Motion

Shulman, Gordon L., Jacob Schwarz, Francis M. Miezin, and Steven E. Petersen. Effect of motion contrast on human cortical responses to moving stimuli. J. Neurophysiol. 79: 2794–2803, 1998. The cortical areas activated by motion-defined contours were studied in humans using positron emission tomography (PET). Subjects observed four types of random dot fields, displayed through a 21° diam aperture: unidirectional motion of a translating dot field, motion in opposing directions of two superimposed translating fields, motion in opposing directions of dots in contiguous spatial regions (motion contrast), producing a square wave grating defined by motion, and luminance variation of stationary dots in contiguous spatial regions, producing a square wave grating defined by luminance. Relative to a static dot field, the unidirectional motion condition activated areas previously described, including areas 17/18, lateral temporal-occipital–parietal cortex (MT/MST), and the superior temporal sulcus. Motion-defined gratings increased the activation of areas 17/18 and MT/MST, but not the superior temporal sulcus, and added more dorsal areas in the cuneus, roughly corresponding to V3/V3a, and ventral areas in the lingual gyrus/collateral sulcus, roughly corresponding to V2/VP. Luminance defined gratings, relative to a static dot field, activated areas 17/18, regions in the dorsal cuneus similar to those activated by motion defined gratings, and a region near the left collateral sulcus, slightly lateral to the motion grating activation. They also activated a region in the right fusiform gyrus that was more weakly activated by the motion grating. These results indicate that adding motion contrast to large moving fields increases activity in areas 17/18 and MT/MST and adds both dorsal and ventral regions that are similar for motion and luminance defined contours.

scholarly journals Primary Gastrointestinal Stromal Tumor of the Liver with Cystic Changes

2019 ◽  
Vol 13 (1) ◽  
pp. 58-65
Author(s):  
Takashi Tashiro ◽  
Fumihiro Uwamori ◽  
Yukiomi Nakade ◽  
Tadahisa Inoue ◽  
Yuji Kobayashi ◽  
...  
Keyword(s):  
Liver Tumors ◽  
Past History ◽  
Brain Infarction ◽  
Arterial Phase ◽  
First Case ◽  
Positron Emission ◽  
Cystic Changes ◽  
Multiple Bone Metastases ◽  
The Right ◽  
Cells Of Cajal

Gastrointestinal stromal tumors (GISTs) are known to originate specifically from the intestinal cells of Cajal located in the gastrointestinal mesenchyme. GISTs developing outside of the digestive tract have barely been reported. We encountered a first case of large primary GISTs in the liver with cystic changes. A 63-year-old man with a past history of brain infarction visited our hospital. The computed tomography (CT) revealed a 6-cm and a 10-cm mass in the right and the caudal lobe of the liver, respectively. These tumors have marginal enhancement in the arterial phase; however, they presented as hypodense in the internal tumor sites. Both liver tumors had cystic changes. Gastrointestinal examinations using endoscopy revealed no other gastrointestinal tumors, and [18F]-fluoro-2-deoxy-D-glucose positron emission tomography/CT revealed multiple bone metastases in addition to the liver tumors. The liver tumor specimens were composed of spindle cells, and the immunohistochemical staining for c-Kit and for DOG1, as discovered on GIST, was positive. The patient was diagnosed with primary hepatic GIST with cystic changes.

scholarly journals Primary pulmonary epithelioid sarcoma: a case report

2021 ◽  
Vol 15 (1) ◽  
Author(s):  
Eiki Mizutani ◽  
Riichiro Morita ◽  
Keiko Abe ◽  
Makoto Kodama ◽  
Shogo Kasai ◽  
...  
Keyword(s):  
Tumor Cells ◽  
Lung Tumor ◽  
Smooth Muscle Actin ◽  
Asbestos Exposure ◽  
Epithelioid Sarcoma ◽  
Whole Body ◽  
Health Examination ◽  
Positron Emission ◽  
Primary Lung Tumor ◽  
The Right

Abstract Background Epithelioid sarcoma most frequently occurs in the dermal or subcutaneous area of the distal extremities. To date, there have been three cases of primary pulmonary epithelioid sarcoma reported. We report a case of epithelioid sarcoma that is considered a primary lung tumor. Case presentation A 65-year-old asymptomatic Asian male patient underwent chest radiography during a routine health examination, and an abnormal mass was detected. His past medical history was unremarkable. He smoked 40 cigarettes every day and had slightly obstructive impairment on spirometry. He worked as an employee of a company and had no history of asbestos exposure. He underwent partial resection of the right lung by thoracoscopy. A histological examination of the tumor revealed a cellular nodule of epithelioid and spindle-shaped cells. Some of the tumor cells displayed rhabdoid features and reticular arrangement in a myxomatous stroma. Immunohistochemically, the tumor cells were positive for vimentin, smooth muscle actin (SMA), CD34, and epithelial membrane antigen (EMA); loss of the BAF47/INI1 protein in the tumor cells was also confirmed. A diagnosis of epithelioid sarcoma was established. Careful screening by whole-body positron emission tomography for another primary lesion after surgery did not detect any possible lesion. He had no cutaneous disease. Conclusion To our knowledge, this is the fourth case of a proximal-type epithelioid sarcoma considered as a primary lung tumor.

scholarly journals Frequency-Dependent Changes of Regional Cerebral Blood Flow during Finger Movements

1996 ◽  
Vol 16 (1) ◽  
pp. 23-33 ◽  
Author(s):  
Norihiro Sadato ◽  
Vicente Ibañez ◽  
Marie-Pierre Deiber ◽  
Gregory Campbell ◽  
Marc Leonardo ◽  
...  
Keyword(s):  
Sensorimotor Cortex ◽  
Anterior Cingulate ◽  
Progressive Change ◽  
Positron Emission ◽  
Primary Sensorimotor Cortex ◽  
Neuronal Recruitment ◽  
Simple Movement ◽  
The Right ◽  
Fast Rates ◽  
Significant Activation

To study the effect of the repetition rate of a simple movement on the distribution and magnitude of neuronal recruitment, we measured regional CBF (rCBF) in eight normal volunteers, using positron emission tomography and 15O-labeled water. An auditory-cued, repetitive flexion movement of the right index finger against the thumb was performed at very slow (0.25 and 0.5 Hz), slow (0.75 and 1 Hz), fast (2 and 2.5 Hz), and very fast (3 and 4 Hz) rates. The increase of rCBF during movement relative to the resting condition was calculated for each pair of movement conditions. Left primary sensorimotor cortex showed no significant activation at the very slow rates. There was a rapid rise of rCBF between the slow and the fast rates, but no further increase at the very fast rates. The right cerebellum showed similar changes. Changes in the left primary sensorimotor cortex and the cerebellum likely reflect the effect of the movement rate. The posterior supplementary motor area (SMA) showed its highest activation at the very slow rates but no significant activation at the very fast rates. Changes correlating with those in the SMA were found in the anterior cingulate gyrus, right prefrontal area, and right thalamus. The decreases in CBF may reflect a progressive change in performance from reactive to predictive.

scholarly journals Prefrontal and striatal dopamine D2/D3 receptors correlate with fMRI BOLD activation during stopping

2021 ◽  
Author(s):  
Philippe Pfeifer ◽  
Alexandra Sebastian ◽  
Hans Georg Buchholz ◽  
Christoph P. Kaller ◽  
Gerhard Gründer ◽  
...  
Keyword(s):  
Dopamine Receptor ◽  
Response Inhibition ◽  
Neural Circuit ◽  
Blood Oxygen Level Dependent ◽  
Stop Signal Task ◽  
Endogenous Opioid System ◽  
Endogenous Opioid ◽  
Genetic Determination ◽  
Positron Emission ◽  
The Right

AbstractD2-like dopamine receptors in animals and humans have been shown to be linked to impulsive behaviors that are highly relevant for several psychiatric disorders. Here, we investigate the relationship between the fronto-striatal D2/D3 dopamine receptor availability and response inhibition in a selected population of healthy OPRM1 G-allele carriers. Twenty-two participants successively underwent blood-oxygen level dependent functional magnetic resonance imaging (fMRI) while performing a stop-signal task and a separate positron emission tomography (PET) scan. Striatal and extrastriatal D2/D3 dopamine receptor availability was measured using the radiotracer [18F]fallypride. Caudate D2/D3 dopamine receptor availability positively correlated with stopping-related fronto-striatal fMRI activation. In addition, right prefrontal D2/D3 dopamine receptor availability correlated positively with stopping-related striatal fMRI BOLD signal. Our study partially replicates previous findings on correlations between striatal D2/D3 dopamine receptor availability and response inhibition in a population selected for its genetic determination of dopamine response to alcohol and as a modulator of impulse control via the endogenous opioid system. We confirm the important role of D2/D3 dopamine receptor availability in the fronto-striatal neural circuit for response inhibition. Moreover, we extend previous findings suggesting that dopamine receptor availability in the right inferior frontal cortex, a crucial region of the stopping network, is also strongly associated with stopping-related striatal fMRI activity in healthy OPRM1 G-allele carriers.

scholarly journals Regional Gas Exchange and Cellular Metabolic Activity in Ventilator-induced Lung Injury

2007 ◽  
Vol 106 (4) ◽  
pp. 723-735 ◽  
Author(s):  
Guido Musch ◽  
Jose G. Venegas ◽  
Giacomo Bellani ◽  
Tilo Winkler ◽  
Tobias Schroeder ◽  
...  
Keyword(s):  
Gas Exchange ◽  
Lung Injury ◽  
Metabolic Activity ◽  
Cell Activation ◽  
Test Lung ◽  
Ventilator Induced Lung Injury ◽  
Positron Emission ◽  
Cellular Metabolic Activity ◽  
The Right ◽  
Tissue Fraction

Background Alveolar overdistension and repetitive derecruitment-recruitment contribute to ventilator-induced lung injury (VILI). The authors investigated (1) whether inflammatory cell activation due to VILI was assessable by positron emission tomography and (2) whether cell activation due to dynamic overdistension alone was detectable when other manifestations of VILI were not yet evident. Methods The authors assessed cellular metabolic activity with [(18)F]fluorodeoxyglucose and regional gas exchange with [(13)N]nitrogen. In 12 sheep, the left ("test") lung was overdistended with end-inspiratory pressure of 50 cm H(2)O for 90 min, while end-expiratory derecruitment of this lung was either promoted with end-expiratory pressure of -10 cm H(2)O in 6 of these sheep (negative end-expiratory pressure [NEEP] group) or prevented with +10 cm H(2)O in the other 6 (positive end-expiratory pressure [PEEP] group) to isolate the effect of overdistension. The right ("control") lung was protected from VILI. Results Aeration decreased and shunt fraction increased in the test lung of the NEEP group. [(18)F]fluorodeoxyglucose uptake of this lung was higher than that of the control lung and of the test lung of the PEEP group, and correlated with neutrophil count. When normalized by tissue fraction to account for increased aeration of the test lung in the PEEP group, [(18)F]fluorodeoxyglucose uptake was elevated also in this group, despite the fact that gas exchange had not yet deteriorated after 90 min of overdistension alone. Conclusion The authors could detect regional neutrophil activation in VILI even when end-expiratory derecruitment was prevented and impairment of gas exchange was not evident. Concomitant end-expiratory derecruitment converted this activation into profound inflammation with decreased aeration and regional shunting.

scholarly journals Primary mucosal malignant melanoma of the nasal cavity

2020 ◽  
Vol 6 (5) ◽  
pp. 988
Author(s):  
Subrata Mukhopadhyay ◽  
Misbahul Haque
Keyword(s):  
Computed Tomography ◽  
Malignant Melanoma ◽  
Nasal Cavity ◽  
Maxillary Antrum ◽  
Positron Emission ◽  
Recurrent Epistaxis ◽  
Mucosal Malignant Melanoma ◽  
The Right ◽  
Primary Mucosal Malignant Melanoma ◽  
Enhanced Computed Tomography

<p>Primary mucosal melanoma of the nasal cavity and paranasal sinuses is a very aggressive and rare disease with only about 0.5 % of malignant melanoma arising from the nasal cavity. There are only few reports from India. We report a rare case of sino-nasal mucosal malignant melanoma in a 58 years old female who presented with blackish coloured sino-nasal mass involving right nasal cavity, spontaneous and recurrent epistaxis and obliteration of the right naso-labial fold with occasional pain in the past 10 months. Contrast enhanced computed tomography scan showed a heterogenous mass involving right nasal cavity, right maxillary antrum and right ethmoidal area. A positron emission tomography computed tomography was also done which showed increased uptake in the region mentioned above. Initial biopsy, the mass was diagnosed as malignant melanoma. Total maxillectomy was performed with plan of post-operative radiotherapy.</p>

scholarly journals Reduced Ventrolateral fMRI Response during Observation of Emotional Gestures Related to the Degree of Dopaminergic Impairment in Parkinson Disease

2009 ◽  
Vol 21 (7) ◽  
pp. 1321-1331 ◽  
Author(s):  
Martin Lotze ◽  
Matthias Reimold ◽  
Ulrike Heymans ◽  
Arto Laihinen ◽  
Marianne Patt ◽  
...  
Keyword(s):  
Parkinson Disease ◽  
Facial Expressions ◽  
Motor Impairment ◽  
Superior Temporal Sulcus ◽  
Healthy Controls ◽  
Emotional Facial Expressions ◽  
Ventrolateral Prefrontal Cortex ◽  
Average Decrease ◽  
Fmri Response ◽  
The Right

Recent findings point to a perceptive impairment of emotional facial expressions in patients diagnosed with Parkinson disease (PD). In these patients, administration of dopamine can modulate emotional facial recognition. We used fMRI to investigate differences in the functional activation in response to emotional and nonemotional gestures between PD patients and age-matched healthy controls (HC). In addition, we used PET to evaluate the striatal dopamine transporter availability (DAT) with [11C]d-threo-methylphenidate in the patient group. Patients showed an average decrease to 26% in DAT when compared to age-corrected healthy references. Reduction in the DAT of the left putamen correlated not only with motor impairment but also with errors in emotional gesture recognition. In comparison to HC, PD patients showed a specific decrease in activation related to emotional gesture observation in the left ventrolateral prefrontal cortex (VLPFC) and the right superior temporal sulcus. Moreover, the less DAT present in the left putamen, the lower the activation in the left VLPFC. We conclude that a loss of dopaminergic neurotransmission in the putamen results in a reduction of ventrolateral prefrontal access involved in the recognition of emotional gestures.

Primary Pericardial Angiosarcoma: A Case Report and Literature Review

2021 ◽  
Author(s):  
hong sun ◽  
min zhao
Keyword(s):  
Literature Review ◽  
Early Stage ◽  
Radical Resection ◽  
Primary Angiosarcoma ◽  
Positron Emission ◽  
Contrast Enhanced ◽  
Wide Range ◽  
The Right ◽  
Enhanced Computed Tomography ◽  
Contrast Enhanced Computed Tomography

Abstract Primary angiosarcoma is extremely rare malignant tumor that has no typical symptoms and progress rapidly with poor prognosis. It is mesenchymal in origin and observed most frequently in the right atrium, cases in the pericardium is much more rare. Only few can detected in the early-stage allowing complete radical resection with a mean survival of 3 months to 1 year. There is few pericardial angiosarcoma reported among these years. The present study reports a case of a 44-year-old woman with primary pericardial angiosarcoma, who underwent a wide range of imaging methods, including transthoracic echocardiography, contrast-enhanced computed tomography (CT) and positron emission tomography-magnetic resonance imaging (PET-MRI). The patient recovered well after operation in two years and died due to the recrudescence and pulmonary metastases in April, 2020. We report the case for its rarity and revealing the early detection of primary pericardial angiosarcoma with imaging examinations is critical for prognosis. Finally a literature review is done.

Whole body muscle activity during weightlifting exercise evaluated by positron emission tomography

2021 ◽  
Author(s):  
Rikuto Yoshimizu ◽  
Junsuke Nakase ◽  
Takafumi Mochizuki ◽  
Yasushi Takata ◽  
Kengo Shimozaki ◽  
...  
Keyword(s):  
Positron Emission Tomography ◽  
Muscle Activity ◽  
Erector Spinae ◽  
Triceps Surae ◽  
Emission Tomography ◽  
Whole Body ◽  
Computed Tomography Images ◽  
Positron Emission ◽  
The Right ◽  
Fdg Accumulation

Abstract BackgroundThis study investigated the whole-body skeletal muscle activity pattern of hang power clean (HPC), a major weight training exercise, using positron emission tomography (PET).MethodTwelve college weightlifting athletes performed three sets of HPC 20 times with a barbell set to 40 kg both before and after an intravenous injection of 37 MBq 18F-fluorodeoxyglucose (FDG). PET-computed tomography images were obtained 50 min after FDG injection. Regions of interest were defined within 71 muscles. The standardized uptake value was calculated to examine the FDG uptake of muscle tissue per unit volume, and FDG accumulation was compared to the control group. The Mann–Whitney U-test was used to evaluate the differences in the mean SUV between groups. The difference between SUVs of the right and left muscles was evaluated by a paired t-test. A P-value < 0.05 was considered statistically significant.ResultsFDG accumulation within the vastus lateralis, vastus intermedius, and vastus medialis was higher than that of the rectus femoris. FDG accumulation within the triceps surae muscle was significantly higher only in the soleus. In the trunk and hip muscles, FDG accumulation of only the erector spinae was significantly increased. In all skeletal muscles, there was no difference between SUVs of the right and left muscles.ConclusionsThe monoarticular muscles in the lower limbs were active in HPC. In contrast, deep muscles in the trunk and hip were not active during HPC. HPC is not suitable for core training and needs to be supplemented with other training.

Sign in / Sign up

Export Citation Format

Share Document