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Nuclear Medicine jobs in "Statewide" - VA

Looking for a job in a big city? Even if you've heard that a market is "saturated", we can help! Many job openings for physicians may be hidden and unavailable unless you know where to look. An excellent

Nuclear Medicine jobs in "Statewide" - TX

Nuclear Medicine jobs in "Statewide" - PA

Looking for a job in a big city? Even if you've heard that a market is "saturated", we can help! Many job openings for physicians may be hidden and unavailable unless you know where to

Nuclear Medicine jobs in "Statewide" - OH

Nuclear Medicine jobs in "Statewide" - NY

Nuclear Medicine jobs in "Statewide" - NJ

Nuclear Medicine jobs in "Statewide" - MD

Nuclear Medicine jobs in "Statewide" - IN

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Nuclear Medicine jobs in "Statewide" - DC

Nuclear Medicine jobs in "Statewide" - CT

Nuclear Medicine jobs in "Statewide" - CA

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Nuclear Medicine jobs in "Jeddah" - SA

Head Medical: Nuclear Medicine Consultant required for the Gulf Region Ref Number: ANS0024 Excellent tax free remuneration packages including; Travel + Housing

Strengthening our profession through community and collaboration.

Strengthening our profession through community and collaboration. J Nucl Med. 2012 Feb;53(2):14N Authors: Fahey FH PMID: 22302970 [PubMed - in process]

SNM Submits Imaging Endpoint Comments to FDA.

SNM Submits Imaging Endpoint Comments to FDA. J Nucl Med. 2012 Feb;53(2):13N Authors: Clarke B, Merrill J PMID: 22302969 [PubMed - in process]

What is an NMAA?

What is an NMAA? J Nucl Med. 2012 Feb;53(2):12N Authors: Botkin C, Henkin R PMID: 22302968 [PubMed - in process]

MedPAC: Imaging Spending Down.

MedPAC: Imaging Spending Down. J Nucl Med. 2012 Feb;53(2):11NA Authors: PMID: 22302967 [PubMed - in process]

From the newsline editor.

From the newsline editor. J Nucl Med. 2012 Feb;53(2):11N Authors: Ziessman H PMID: 22302966 [PubMed - in process]

Molecular Imaging of Early αvβ3 Integrin Expression Predicts Long-Term Left-Ventricle Remodeling After Myocardial Infarction in Rats.

Molecular Imaging of Early αvβ3 Integrin Expression Predicts Long-Term Left-Ventricle Remodeling After Myocardial Infarction in Rats. J Nucl Med. 2012 Feb;53(2):318-23 Authors: Sherif HM, Saraste A, Nekolla SG, Weidl E, Reder S, Tapfer A, Rudelius M, Higuchi T, Botnar RM, Wester HJ, Schwaiger M Abstract UNLABELLED: (18)F-galacto-RGD ((18)F-RGD) is a PET tracer binding to α(v)β(3) integrin receptors that are upregulated after myocardial infarction (MI) as part of the healing process. We studied whether myocardial (18)F-RGD uptake early after MI is associated with long-term left-ventricle (LV) remodeling in a rat model. METHODS: Wistar rats underwent sham operation (n = 9) or permanent coronary ligation (n = 25). One week after MI, rats were injected with (18)F-RGD to evaluate α(v)β(3) integrin expression using a preclinical PET system. In the same rats, LV volumes and defect size were measured 1 and 12 wk after MI by (13)N-ammonia PET and MRI, respectively. RESULTS: One week after MI, (18)F-RGD uptake was increased in the defect area as compared with the remote myocardium of MI rats or sham-operated controls (percentage injected dose per cubic centimeter, 0.20 ± 0.05 vs. 0.06 ± 0.03 and 0.07 ± 0.04, P < 0.001). At this time, (18)F-RGD uptake was associated with capillary density in histologic sections. Average (18)F-RGD uptake in the defect area was lowest in the rats demonstrating greater than 20% relative increase in the LV end-diastolic volume from 1 to 12 wk (percentage injected dose per centimeter cubed, 0.15 ± 0.07 vs. 0.21 ± 0.05, P < 0.05). In a multivariable logistic regression analysis, low (18)F-RGD uptake was a significant predictor of increase in end-diastolic volume (r = 0.51, P < 0.05). CONCLUSION: High levels of (18)F-RGD uptake in the perfusion defect area early after MI were associated with the absence of significant LV remodeling after 12 wk of follow-up. These results suggest that α(v)β(3) integrin expression is a potential biomarker of myocardial repair processes after MI and enables the monitoring of these processes by molecular imaging to derive possible prognostic information. PMID: 22302965 [PubMed - in process]

Stratification of Nucleoside Analog Chemotherapy Using 1-(2'-Deoxy-2'-18F-Fluoro-β-D-Arabinofuranosyl)Cytosine and 1-(2'-Deoxy-2'-18F-Fluoro-β-L-Arabinofuranosyl)-5-Methylcytosine PET.

Stratification of Nucleoside Analog Chemotherapy Using 1-(2'-Deoxy-2'-18F-Fluoro-β-D-Arabinofuranosyl)Cytosine and 1-(2'-Deoxy-2'-18F-Fluoro-β-L-Arabinofuranosyl)-5-Methylcytosine PET. J Nucl Med. 2012 Feb;53(2):275-80 Authors: Lee JT, Campbell DO, Satyamurthy N, Czernin J, Radu CG Abstract UNLABELLED: The ability to measure tumor determinants of response to nucleoside analog (NA) chemotherapy agents such as gemcitabine and related compounds could significantly affect the management of several types of cancer. Previously we showed that the accumulation in tumors of the new PET tracer 1-(2'-deoxy-2'-(18)F-fluoro-β-d-arabinofuranosyl)cytosine ((18)F-FAC) is predictive of responses to gemcitabine. (18)F-FAC retention in cells requires deoxycytidine kinase (dCK), a rate-limiting enzyme in the deoxyribonucleoside salvage metabolism and in gemcitabine conversion from an inactive prodrug to a cytotoxic compound. The objectives of the current study were to determine whether (18)F-FAC tumor uptake is also influenced by cytidine deaminase (CDA), a determinant of resistance to gemcitabine; to develop a new PET assay using (18)F-FAC and the related probe 1-(2'-deoxy-2'-(18)F-fluoro-β-l-arabinofuranosyl)-5-methylcytosine (l-(18)F-FMAC) to profile tumor lesions for both dCK and CDA enzymatic activities; and to determine whether this PET assay can identify the most effective NA chemotherapy against tumors with differential expression of dCK and CDA. METHODS: Isogenic murine leukemic cell lines with defined dCK and CDA activities were generated by retroviral transduction. A cell viability assay was used to determine the sensitivity of the isogenic cell lines to the dCK-dependent NA prodrugs gemcitabine and clofarabine. In vitro enzymatic and cell-based tracer uptake assays and in vivo PET with (18)F-FAC and l-(18)F-FMAC were used to predict tumor responses to gemcitabine and clofarabine. RESULTS: dCK and CDA activities measured by kinase and tracer uptake assays correlated with the sensitivity of isogenic cell lines to gemcitabine and clofarabine. Coexpression of CDA decreased the sensitivity of dCK-positive cells to gemcitabine treatment in vitro by 15-fold but did not affect responses to clofarabine. Coexpression of CDA decreased (18)F-FAC but not l-(18)F-FMAC, phosphorylation, and uptake by dCK-positive cells. (18)F-FAC and l-(18)F-FMAC PET estimates of the enzymatic activities of dCK and CDA in tumor implants in mice were predictive of responses to gemcitabine and clofarabine treatment in vivo. CONCLUSION: These findings support the utility of PET-based phenotyping of tumor nucleoside metabolism for guiding the selection of NA prodrugs. PMID: 22302964 [PubMed - in process]

Modern Nuclear Imaging for Paragangliomas: Beyond SPECT.

Modern Nuclear Imaging for Paragangliomas: Beyond SPECT. J Nucl Med. 2012 Feb;53(2):264-74 Authors: Taïeb D, Neumann H, Rubello D, Al-Nahhas A, Guillet B, Hindié E Abstract Paragangliomas are rare neuroendocrine tumors that may arise anywhere along the paraganglial system, with a high frequency of hereditary forms or multifocal disease. Most often, paragangliomas are benign and progress slowly, but metastases may occur in about 10% of patients. In this respect, nuclear imaging in combination with anatomic imaging may be required to fully delineate the extent of the disease. PET has been increasingly used in imaging paraganglioma, paralleled by great efforts toward the development of new tracers. Recent data indicate that the choice of PET tracers should be tailored to tumor localization and to the patient's genetic status. This article provides insight into the many PET radiotracers that are currently available and others that are still only under research and guides clinicians toward appropriate use in relation to genetic carrier status. In addition, this article provides nuclear medicine physicians with the background knowledge required for understanding relationships between imaging phenotypes and molecular genetics. PMID: 22302963 [PubMed - in process]

Dosimetry Based on 99mTc-Macroaggregated Albumin SPECT/CT Accurately Predicts Tumor Response and Survival in Hepatocellular Carcinoma Patients Treated with 90Y-Loaded Glass Microspheres: Preliminary Results.

Dosimetry Based on 99mTc-Macroaggregated Albumin SPECT/CT Accurately Predicts Tumor Response and Survival in Hepatocellular Carcinoma Patients Treated with 90Y-Loaded Glass Microspheres: Preliminary Results. J Nucl Med. 2012 Feb;53(2):255-63 Authors: Garin E, Lenoir L, Rolland Y, Edeline J, Mesbah H, Laffont S, Porée P, Clément B, Raoul JL, Boucher E Abstract UNLABELLED: Radioembolization of liver cancers using (90)Y-loaded microspheres is experiencing more widespread use. However, few data are available concerning the doses delivered to the tumors and the healthy liver. This retrospective study was conducted to calculate the tumor dosimetry (planned tumor dose [T(plan) D]) and nontumor dosimetry in patients treated by (90)Y-loaded glass microspheres and determine whether tumor dosimetry could predict response and survival. METHODS: Thirty-six patients with hepatocellular carcinoma (HCC), including 16 with portal vein thrombosis (PVT), were treated with (90)Y-loaded glass microspheres. The T(plan) D and the dose delivered to the injected healthy liver were calculated using a quantitative analysis of the (99m)Tc-macroaggregated albumin ((99m)Tc-MAA) SPECT/CT exam. Responses were assessed after 3 mo, using the criteria of the European Association for the Study of the Liver. Progression-free survival (PFS) and overall survival (OS) were evaluated using Kaplan-Meier tests. RESULTS: The response rate was 69% for the overall population and 75% for the PVT patients. The dose delivered to the tumor was the only parameter associated with response with multivariate analysis (P = 0.019). A threshold T(plan) D value of 205 Gy was predictive of response, with a sensitivity of 100% and an accuracy of 91%. Quantitative (99m)Tc-MAA SPECT/CT allowed us to increase the injected activity for 4 patients with large lesions. PFS was only 5.2 mo and OS 9 mo when using a T(plan) D of less than 205 Gy versus 14 mo (P = 0.0003) and 18 mo (P = 0.0322), respectively, with a T(plan) D of 205 Gy or more. CONCLUSION: Quantitative (99m)Tc-MAA SPECT/CT is predictive of response, PFS, and OS. Dosimetry based on (99m)Tc-MAA SPECT/CT can be used for the selection of patients and for an adaptation of treatment planning, especially in selected patients (particularly in the case of large tumors). These results also confirm the efficacy and safety of (90)Y-loaded microspheres in treating HCC, even in the presence of PVT (and especially when (99m)Tc-MAA uptake is seen inside the PVT). PMID: 22302962 [PubMed - in process]

Performance of 18F-Fluoro-Ethyl-Tyrosine (18F-FET) PET for the Differential Diagnosis of Primary Brain Tumor: A Systematic Review and Metaanalysis.

Performance of 18F-Fluoro-Ethyl-Tyrosine (18F-FET) PET for the Differential Diagnosis of Primary Brain Tumor: A Systematic Review and Metaanalysis. J Nucl Med. 2012 Feb;53(2):207-14 Authors: Dunet V, Rossier C, Buck A, Stupp R, Prior JO Abstract UNLABELLED: For the past decade, PET with (18)F-fluoro-ethyl-tyrosine ((18)F-FET) has been used in the evaluation of patients with primary brain tumors (PBTs), but so far series have reported only a limited number of patients. The purpose of this systematic review and metaanalysis was to assess the diagnostic performance of (18)F-FET PET in patients with suspicion of PBT. METHODS: We examined studies published in the literature using MEDLINE and EMBASE databases. Inclusion criteria were use of (18)F-FET PET for initial assessment of patients with a newly diagnosed brain lesion; patients who had no radiotherapy, surgery, or chemotherapy before (18)F-FET PET; and use of histology as a gold standard. Metaanalysis was performed on a per-patient basis. We secondarily performed receiver-operating-characteristic analysis of pooled patients to determine tumor-to-background ratio (TBR) of (18)F-FET uptake and best diagnostic value. RESULTS: Thirteen studies totaling 462 patients were included. For the diagnosis of PBT, (18)F-FET PET demonstrated a pooled sensitivity of 0.82 (95% confidence interval [CI], 0.74-0.88), specificity of 0.76 (95% CI, 0.44-0.92), area under the curve of 0.84 (95% CI, 0.80-0.87), positive likelihood ratio of 3.4 (95% CI, 1.2-9.5), and negative likelihood ratio of 0.24 (95% CI, 0.14-0.39). Receiver-operating-characteristic analysis indicated that a mean TBR threshold of at least 1.6 and a maximum TBR of at least 2.1 had the best diagnostic value for differentiating PBTs from nontumoral lesions. CONCLUSION: (18)F-FET PET demonstrated excellent performance for diagnosing PBTs. Strict standardization of PET acquisition protocols and prospective, multicenter studies investigating the added value over current MRI are now needed to establish (18)F-FET PET as a highly relevant tool for patient management. PMID: 22302961 [PubMed - in process]

Promising New Photon Detection Concepts for High-Resolution Clinical and Preclinical PET.

Promising New Photon Detection Concepts for High-Resolution Clinical and Preclinical PET. J Nucl Med. 2012 Feb;53(2):167-70 Authors: Levin CS Abstract The ability of PET to visualize and quantify regions of low concentration of PET tracer representing subtle cellular and molecular signatures of disease depends on relatively complex biochemical, biologic, and physiologic factors that are challenging to control, as well as on instrumentation performance parameters that are, in principle, still possible to improve on. Thus, advances to the latter can somewhat offset barriers of the former. PET system performance parameters such as spatial resolution, contrast resolution, and photon sensitivity contribute significantly to PET's ability to visualize and quantify lower concentrations of signal in the presence of background. In this report we present some technology innovations under investigation toward improving these PET system performance parameters. We focus particularly on a promising advance known as 3-dimensional position-sensitive detectors, which are detectors capable of distinguishing and measuring the position, energy, and arrival time of individual interactions of multi-interaction photon events in 3 dimensions. If successful, these new strategies enable enhancements such as the detection of fewer diseased cells in tissue or the ability to characterize lower-abundance molecular targets within cells. Translating these advanced capabilities to the clinic might allow expansion of PET's roles in disease management, perhaps to earlier stages of disease. In preclinical research, such enhancements enable more sensitive and accurate studies of disease biology in living subjects. PMID: 22302960 [PubMed - in process]

Synthesis and Preliminary Evaluation of 18F-Labeled Pyridaben Analogues for Myocardial Perfusion Imaging with PET.

Synthesis and Preliminary Evaluation of 18F-Labeled Pyridaben Analogues for Myocardial Perfusion Imaging with PET. J Nucl Med. 2012 Feb 2; Authors: Mou T, Zhao Z, Fang W, Peng C, Guo F, Liu B, Ma Y, Zhang X Abstract In this study the (18)F-labeled pyridaben analogs 2-tertbutyl-4-chloro-5-(4-(2-(18)F-fluoroethoxy))benzyloxy-2H-pyridazin-3-one ((18)F-FP1OP) and 2-tertbutyl-4-chloro-5-(4-(2-(2-(2-(18)F-fluoroethoxy)ethoxy)ethoxy))benzyloxy-2H-pyridazin-3-one ((18)F-FP3OP) were synthesized, characterized, and evaluated as potential myocardial perfusion imaging (MPI) agents with PET. METHODS: The tosylate labeling precursors of 2-tert-butyl-4-chloro-5-(4-(2-tosyloxy-ethoxy))-benzyloxy-2H-pyridazin-3-one (OTs-P1OP), 2-tert-butyl-4-chloro-5-(4-(2-(2-(2-tosyloxy-ethoxy)ethoxy)ethoxy))-benzyloxy-2H-pyridazin-3-one (OTs-P3OP), and the corresponding nonradioactive compounds ((19)F-FP1OP and (19)F-FP3OP) were synthesized and characterized by infrared, (1)H nuclear magnetic resonance, (13)C nuclear magnetic resonance, and mass spectrometry analysis. (18)F-FP1OP and (18)F-FP3OP were obtained by 1-step nucleophilic substitution of tosyl with (18)F and evaluated as MPI agents in vitro (physicochemical properties, stability), ex vivo (autoradiography), and in vivo (toxicity and biodistribution in normal mice; cardiac PET in healthy Chinese mini swine and in acute myocardial infarction and chronic myocardial ischemia models). RESULTS: The total radiosynthesis time of both tracers, including final high-pressure liquid chromatography purification, was about 70-90 min. Typical decay-corrected radiochemical yields were about 50%, and the radiochemical purities were more than 98% after purification. (18)F-FP1OP had lower hydrophilicity and higher water stability than that of (18)F-FP3OP. In biodistribution studies, both (18)F-FP1OP and (18)F-FP3OP had high heart uptake (31.13 ± 6.24 and 31.10 ± 3.72 percentage injected dose per gram at 2 min after injection, respectively) and high heart-to-liver, heart-to-lung, and heart-to-blood ratios at all time points after injection. Further autoradiography evaluation of (18)F-FP1OP showed that the heart uptake could be blocked effectively by rotenone or nonradioactive (19)F-FP1OP. Clear cardiac PET images of (18)F-FP1OP were obtained in healthy Chinese mini swine at 2, 15, 30, 60, and 120 min after injection, and the uptake of perfusion deficit areas was much lower than in normal tissue in both acute myocardial infarction and chronic myocardial ischemia models. CONCLUSION: The (18)F-labeled pyridaben analogs reported in this study have high heart uptake and low background uptake in both the mouse model and the Chinese mini swine model. The tracer with the shorter radiolabeling side chain ((18)F-FP1OP) has better stability, faster clearance from the major organs, and a higher heart-to-liver ratio than the other tracer ((18)F-FP3OP). On the basis of the promising biologic properties, this mitochondrial complex I-targeted tracer ((18)F-FP1OP) is worthy to be developed as an MPI agent and to be compared with the other PET MPI agents in the future. PMID: 22302832 [PubMed - as supplied by publisher]