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Purpose Dissolution dynamic nuclear polarization can increase the sensitivity of the 13C magnetic resonance spectroscopy experiment by at least four orders of magnitude and offers a novel approach to the development of MRI gene reporters based on enzymes that metabolize 13C‐labeled tracers. We describe here a gene reporter based on the enzyme pyruvate decarboxylase (EC 4.1.1.1), which catalyzes the decarboxylation of pyruvate to produce acetaldehyde and carbon dioxide. Methods Pyruvate decarboxylase from Zymomonas mobilis (zmPDC) and a mutant that lacked enzyme activity were expressed using an inducible promoter in human embryonic kidney (HEK293T) cells. Enzyme activity was measured in the cells and in xenografts derived from the cells using 13C MRS measurements of the conversion of hyperpolarized [1‐13C] pyruvate to H13 CO3–. Results Induction of zmPDC expression in the cells and in the xenografts derived from them resulted in an approximately two‐fold increase in the H13 CO3–/[1‐13C] pyruvate signal ratio following intravenous injection of hyperpolarized [1‐13C] pyruvate. Conclusion We have demonstrated the feasibility of using zmPDC as an in vivo reporter gene for use with hyperpolarized 13C MRS. Magn Reson Med 76:391–401, 2016. © 2015 The Authors. Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

$\textbf{Purpose}$ To develop an image analysis technique that distinguishes pseudoprogression from true progression by analyzing tumour heterogeneity in $T_2$-weighted images using topological descriptors of image heterogeneity called Minkowski functionals (MFs). $\textbf{Methods}$ Using a retrospective patient cohort ($n$ = 50), and blinded to treatment response outcome, unsupervised feature estimation was performed to investigate MFs for the presence of outliers, potential confounders, and sensitivity to treatment response. The progression and pseudoprogression groups were then unblinded and supervised feature selection was performed using MFs, size and signal intensity features. A support vector machine model was obtained and evaluated using a prospective test cohort. $\textbf{Results}$ The model gave a classification accuracy, using a combination of MFs and size features, of more than 85% in both retrospective and prospective datasets. A different feature selection method (Random Forest) and classifier (Lasso) gave the same results. Although not apparent to the reporting radiologist, the $T_2$-weighted hyperintensity phenotype of those patients with progression was heterogeneous, large and frond-like when compared to those with pseudoprogression. $\textbf{Conclusion}$ Analysis of heterogeneity, in $T_2$-weighted MR images, which are acquired routinely in the clinic, has the potential to detect an earlier treatment response allowing an early change in treatment strategy. Prospective validation of this technique in larger datasets is required.

Project Volunteer Power was a Manpower Administration pilot program in three cities (Birmingham, Minneapolis, and Malden, Massachusetts) using volunteer women's organizations on a planned basis to develop employment opportunities for the physically handicapped, the mentally retarded, and the mentally restored. (Author/BP)

Describes problems persons with a criminal record encounter in attempting to locate a job. Describes the National Clearinghouse on Offender Employment Restrictions established in 1971 and the steps it is taking to change laws to make it easier for ex-offenders to obtain jobs. (EJT)

Coca Cola's Agricultural Labor Project was designed to change the migrant's way of life from very unstable to stable by making migrant housing more habitable, creating permanent jobs, and providing numerous other fringe benefits. (BP)

Seven years after the Brooklyn Navy Yard was closed, the Yard was reopened through the efforts of Seatrain Shipbuilding Corporation to build oil tankers. A training program for unemployed and unskilled minority group members in the area of the yard was established through JOBS, revitalizing an economically depressed area. (AG)

Wildcat Service Corporation is a highly successful employment service for ex-drug addicts and alcholics who have served prison terms, are on welfare, and have little work experience. Funded mainly by the Manpower Administration, Wildcats's 3,000 workers perform service operations for many of New York City's government departments and businesses. (DS)

Traces the development of the concept of free public education for workers, children and adults, from the 1820's into the 1900's, through organized labor's efforts to implement such education. (MF)

Study finds job training compares favorably with that offered by public institutions. (Editor)

Early debate over employment service echoed contending demands of liberty and order. (Editor)

Army expands use of trainee instructors after successful test with wiremen. (Editor)

New York police, fire fighters prepare for postretirement careers as nurses. (Editor)

Study traces labor market experiences of group of men over a 5-year span. (Editor)

PURPOSE: Dissolution dynamic nuclear polarization can increase the sensitivity of the (13) C magnetic resonance spectroscopy experiment by at least four orders of magnitude and offers a novel approach to the development of MRI gene reporters based on enzymes that metabolize (13) C-labeled tracers. We describe here a gene reporter based on the enzyme pyruvate decarboxylase (EC 4.1.1.1), which catalyzes the decarboxylation of pyruvate to produce acetaldehyde and carbon dioxide. METHODS: Pyruvate decarboxylase from Zymomonas mobilis (zmPDC) and a mutant that lacked enzyme activity were expressed using an inducible promoter in human embryonic kidney (HEK293T) cells. Enzyme activity was measured in the cells and in xenografts derived from the cells using (13) C MRS measurements of the conversion of hyperpolarized [1-(13) C] pyruvate to H(13) CO3-. RESULTS: Induction of zmPDC expression in the cells and in the xenografts derived from them resulted in an approximately two-fold increase in the H(13) CO3-/[1-(13) C] pyruvate signal ratio following intravenous injection of hyperpolarized [1-(13) C] pyruvate. CONCLUSION: We have demonstrated the feasibility of using zmPDC as an in vivo reporter gene for use with hyperpolarized (13) C MRS. Magn Reson Med 76:391-401, 2016. © 2015 The Authors. Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

There is an expanding research interest in high-grade gliomas because of their significant population burden and poor survival despite the extensive standard multimodal treatment. One of the obstacles is the lack of individualized monitoring of tumor characteristics and treatment response before, during and after treatment. We have developed a two-stage semi-automatic method to co-register MRI scans at different time points before and after surgical and adjuvant treatment of high-grade gliomas. This two-stage co-registration includes a linear co-registration of the semi-automatically derived mask of the preoperative contrast-enhancing area or postoperative resection cavity, brain contour and ventricles between different time points. The resulting transformation matrix was then applied in a non-linear manner to co-register conventional contrast-enhanced T1 -weighted images. Targeted registration errors were calculated and compared with linear and non-linear co-registered images. Targeted registration errors were smaller for the semi-automatic non-linear co-registration compared with both the non-linear and linear co-registered images. This was further visualized using a three-dimensional structural similarity method. The semi-automatic non-linear co-registration allowed for optimal correction of the variable brain shift at different time points as evaluated by the minimal targeted registration error. This proposed method allows for the accurate evaluation of the treatment response, essential for the growing research area of brain tumor imaging and treatment response evaluation in large sets of patients. Copyright © 2016 John Wiley & Sons, Ltd.