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Biomedical subjects

Janet Sangare

Publications and source records attributed to Janet Sangare.

4 recordsLinked to original sources

PET [11C]DASB imaging of serotonin transporters in patients with alcoholism.

OBJECTIVE: Alcoholism and aggression have each been associated with neurochemical measurements suggestive of decreased serotonin synaptic transmission. We measured densities of the serotonin transporter (SERT) in a moderate-sized sample of alcoholic patients who were assessed for aggressive characteristics. METHODS: Thirty alcoholic inpatients and 18 healthy controls received a PET scan with [(11)C]-3-amino-4-(2-dimethylaminomethylphenylsulfanyl)-benzonitrile. The alcoholic inpatients were classified as aggressive or nonaggressive based on a comparison between the top third and bottom third scores on the Buss-Durkee Hostility Index. RESULTS: Using a pixel-wise comparison, no brain region showed significant alterations in SERT binding among the 3 groups of subjects (aggressive alcoholic subjects, nonaggressive alcoholic subjects, and healthy controls) or between the combined alcoholic group and healthy controls. None of the clinical measures (including measures of aggression) correlated with SERT binding in the alcoholic subjects. CONCLUSION: Contrary to prior imaging reports using the nonselective ligand [(123)I]beta-CIT, we found no significant alterations of SERT density in alcoholic patients.

Adult↗

Widespread decrease of nicotinic acetylcholine receptors in Parkinson's disease.

OBJECTIVE: Nicotinic acetylcholine receptors have close interactions with the dopaminergic system and play critical roles in cognitive function. The purpose of this study was to compare these receptors between living PD patients and healthy subjects. METHODS: Nicotinic acetylcholine receptors were imaged in 10 nondemented Parkinson's disease patients and 15 age-matched healthy subjects using a single-photon emission computed tomography ligand [(123)I]5-iodo-3-[2(S)-2-azetidinylmethoxy]pyridine. Using an arterial input function, we measured the total distribution volume (V; specific plus nondisplaceable), as well as the delivery (K(1)). RESULTS: Parkinson's disease showed a widespread significant decrease (approximately 10%) of V in both cortical and subcortical regions without a significant change in K(1). INTERPRETATION: These results indicate the importance of extending the study to demented patients.

Aged↗

Whole-body biodistribution and estimation of radiation-absorbed doses of the dopamine D1 receptor radioligand 11C-NNC 112 in humans.

UNLABELLED: The present study estimated radiation-absorbed doses of the dopamine D(1) receptor radioligand [(11)C]((+)-8-chloro-5-(7-benzofuranyl)-7-hydroxy-3-methyl-2,3,4,5-tetrahydro-1H-3-benzazepine) (NNC 112) in humans, based on dynamic whole-body PET in healthy subjects. METHODS: Whole-body PET was performed on 7 subjects after injection of 710 +/- 85 MBq of (11)C-NNC 112. Fourteen frames were acquired for a total of 120 min in 7 segments of the body. Regions of interest were drawn on compressed planar images of source organs that could be identified. Radiation dose estimates were calculated from organ residence times using the OLINDA 1.0 program. RESULTS: The organs with the highest radiation-absorbed doses were the gallbladder, liver, lungs, kidneys, and urinary bladder wall. Biexponential fitting of mean bladder activity demonstrated that 15% of activity was excreted via the urine. With a 2.4-h voiding interval, the effective dose was 5.7 microSv/MBq (21.1 mrem/mCi). CONCLUSION: (11)C-NNC 112 displays a favorable radiation dose profile in humans and would allow multiple PET examinations per year to be performed on the same subject.

Adult↗

PET imaging of serotonin transporters with [11C]DASB: test-retest reproducibility using a multilinear reference tissue parametric imaging method.

UNLABELLED: Parametric imaging of serotonin transporters (SERT) with 11C-labeled 3-amino-4-(2-dimethylaminomethyl-phenylsulfanyl)benzonitrile ([11C]DASB) PET is a useful data analysis tool. The purpose of this study was to evaluate the reproducibility of measurements of SERT binding potential (BP) and relative blood flow (R1) by a 2-parameter multilinear reference tissue parametric imaging method (MRTM2) for human [11C]DASB studies. METHODS: Eight healthy subjects (3 men, 5 women; age, 26 +/- 9 y) underwent 2 [11C]DASB PET scans separated by 1 h on the same day (dose, 703 +/- 111 MBq). Parametric images of BP and R1 were generated by MRTM2 using the cerebellum as a reference region. The k'2 (clearance rate constant from the reference region) required by MRTM2 was estimated by the 3-parameter MRTM. Reproducibility of BP and R1 measurements was evaluated by calculating bias (100 x (retest - test/test), variability (SD of the bias), and reliability (intraclass correlation coefficient = rho) for several representative regions of interest (ROIs). BP and R1 were estimated for ROI time-activity curves fitted by MRTM2 and were compared with those based on the parametric images. RESULTS: The test-retest (0.066 +/- 0.013/0.06 +/- 0.011 min(-1)) MRTM k'2 reproducibility was excellent with small bias (3%) and variability (6%) and high reliability (0.95). Retest BP values were consistently lower than those of test BP values in all regions (a mean negative bias of approximately 6%; P < 0.001). The test-retest BP variability was relatively small, ranging from 4% to 13%, with rho ranging from 0.44 to 0.85. In contrast to BP, test-retest R1 values were similar with negligible bias of < or =0.1%. The test-retest R1 variability was excellent and smaller than that of BP ranging from 3% to 6%, with rho ranging from 0.58 to 0.95. BP and R1 values estimated by the ROI time-activity curve-fitting method were slightly lower ( approximately 3% and approximately 1%, respectively) than those by the parametric imaging method (P < 0.001). However, the test-retest bias and variability of BP and R1 were very similar for both ROI and parametric methods. CONCLUSION: Our results suggest that [11C]DASB parametric imaging of BP and R1 with the noninvasive MRTM2 method is reproducible and reliable for PET studies of SERT.

Adult↗