R W Howell

Summary

Affiliation: New Jersey
Country: USA

Publications

  1. pmc Monte Carlo simulation of irradiation and killing in three-dimensional cell populations with lognormal cellular uptake of radioactivity
    Roger W Howell
    Department of Radiology, Division of Radiation Research, University of Medicine and Dentistry of New Jersey New Jersey Medical School Cancer Center, Newark, NJ 07103, USA
    Int J Radiat Biol 88:115-22. 2012
  2. pmc Auger processes in the 21st century
    Roger W Howell
    Department of Radiology, New Jersey Medical School, University of Medicine and Dentistry of New Jersey, Newark, NJ, USA
    Int J Radiat Biol 84:959-75. 2008
  3. pmc Challenges and progress in predicting biological responses to incorporated radioactivity
    R W Howell
    Department of Radiology, UMDNJ New Jersey Medical School, Newark, NJ 07103, USA
    Radiat Prot Dosimetry 122:521-7. 2006
  4. pmc Modeling multicellular response to nonuniform distributions of radioactivity: differences in cellular response to self-dose and cross-dose
    Roger W Howell
    Division of Radiation Research, Department of Radiology, New Jersey Medical School, University of Medicine and Dentistry of New Jersey, Newark, New Jersey 07103, USA
    Radiat Res 163:216-21. 2005
  5. pmc Bystander effects caused by nonuniform distributions of DNA-incorporated (125)I
    Roger W Howell
    Division of Radiation Research, Department of Radiology, University of Medicine and Dentistry of New Jersey, New Jersey Medical School, Newark, NJ 07103, USA
    Micron 33:127-32. 2002
  6. ncbi request reprint Radioprotection against biological effects of internal radionuclides in vivo by S-(2-aminoethyl)isothiouronium bromide hydrobromide (AET)
    V R Narra
    Department of Radiology, University of Medicine and Dentistry of New Jersey, Newark 07103
    J Nucl Med 36:259-66. 1995
  7. pmc Isolating effects of microscopic nonuniform distributions of (131)I on labeled and unlabeled cells
    Prasad V S V Neti
    Department of Radiology, New Jersey Medical School, University of Medicine and Dentistry of New Jersey, Newark, New Jersey 07103, USA
    J Nucl Med 45:1050-8. 2004
  8. pmc Bystander responses in three-dimensional cultures containing radiolabelled and unlabelled human cells
    M Pinto
    Department of Radiology, UMDNJ New Jersey Medical School, MSB F 451, 185 South Orange Avenue, Newark, NJ 07103, USA
    Radiat Prot Dosimetry 122:252-5. 2006
  9. pmc When may a nonuniform distribution of 131I be considered uniform? An experimental basis for multicellular dosimetry
    Prasad V S V Neti
    Division of Radiation Research, Department of Radiology, New Jersey Medical School, University of Medicine and Dentistry of New Jersey, Newark, New Jersey 07103, USA
    J Nucl Med 44:2019-26. 2003
  10. ncbi request reprint Relative biological effectiveness of 99mTc radiopharmaceuticals
    V R Narra
    Department of Radiology, University of Medicine and Dentistry of New Jersey, Newark 07103
    Med Phys 21:1921-6. 1994

Research Grants

Collaborators

Detail Information

Publications31

  1. pmc Monte Carlo simulation of irradiation and killing in three-dimensional cell populations with lognormal cellular uptake of radioactivity
    Roger W Howell
    Department of Radiology, Division of Radiation Research, University of Medicine and Dentistry of New Jersey New Jersey Medical School Cancer Center, Newark, NJ 07103, USA
    Int J Radiat Biol 88:115-22. 2012
    ..The present work develops theoretical models to simulate these observations...
  2. pmc Auger processes in the 21st century
    Roger W Howell
    Department of Radiology, New Jersey Medical School, University of Medicine and Dentistry of New Jersey, Newark, NJ, USA
    Int J Radiat Biol 84:959-75. 2008
    ..This article provides a review of the research in this field that was published during the years 2004-2007, the period that has elapsed since the previous meeting...
  3. pmc Challenges and progress in predicting biological responses to incorporated radioactivity
    R W Howell
    Department of Radiology, UMDNJ New Jersey Medical School, Newark, NJ 07103, USA
    Radiat Prot Dosimetry 122:521-7. 2006
    ..Evidence shows that even under conditions of 'uniform' distribution of radioactivity, a combination of organ dosimetry, voxel dosimetry and dosimetry at the cellular and multicellular levels can be required to predict response...
  4. pmc Modeling multicellular response to nonuniform distributions of radioactivity: differences in cellular response to self-dose and cross-dose
    Roger W Howell
    Division of Radiation Research, Department of Radiology, New Jersey Medical School, University of Medicine and Dentistry of New Jersey, Newark, New Jersey 07103, USA
    Radiat Res 163:216-21. 2005
    ....
  5. pmc Bystander effects caused by nonuniform distributions of DNA-incorporated (125)I
    Roger W Howell
    Division of Radiation Research, Department of Radiology, University of Medicine and Dentistry of New Jersey, New Jersey Medical School, Newark, NJ 07103, USA
    Micron 33:127-32. 2002
    ..These experimental data, coupled with theoretical dosimetry calculations, indicate that bystander effects play an important role in the killing of unlabeled cells when nonuniform distributions of DNA-incorporated (125)I are present...
  6. ncbi request reprint Radioprotection against biological effects of internal radionuclides in vivo by S-(2-aminoethyl)isothiouronium bromide hydrobromide (AET)
    V R Narra
    Department of Radiology, University of Medicine and Dentistry of New Jersey, Newark 07103
    J Nucl Med 36:259-66. 1995
    ..The observed DMFs for AET also support our earlier premise that the mechanism by which DNA-incorporated Auger emitters impart biological damage is primarily radical mediated, and hence indirect in nature...
  7. pmc Isolating effects of microscopic nonuniform distributions of (131)I on labeled and unlabeled cells
    Prasad V S V Neti
    Department of Radiology, New Jersey Medical School, University of Medicine and Dentistry of New Jersey, Newark, New Jersey 07103, USA
    J Nucl Med 45:1050-8. 2004
    ..On the other hand, unlabeled cells only receive a cross-dose. This work uses a novel approach to examine the lethal effects of microscopic nonuniformities of (131)I individually on the labeled and unlabeled cells...
  8. pmc Bystander responses in three-dimensional cultures containing radiolabelled and unlabelled human cells
    M Pinto
    Department of Radiology, UMDNJ New Jersey Medical School, MSB F 451, 185 South Orange Avenue, Newark, NJ 07103, USA
    Radiat Prot Dosimetry 122:252-5. 2006
    ..No delay occurred in progression of bystander cells through G(1), when the labelled cells were irradiated at dose rates up to 0.32 Gy h(-1)...
  9. pmc When may a nonuniform distribution of 131I be considered uniform? An experimental basis for multicellular dosimetry
    Prasad V S V Neti
    Division of Radiation Research, Department of Radiology, New Jersey Medical School, University of Medicine and Dentistry of New Jersey, Newark, New Jersey 07103, USA
    J Nucl Med 44:2019-26. 2003
    ..This work uses a cell culture model to examine the impact of nonuniformity at the multicellular level on the lethal effects of (131)I...
  10. ncbi request reprint Relative biological effectiveness of 99mTc radiopharmaceuticals
    V R Narra
    Department of Radiology, University of Medicine and Dentistry of New Jersey, Newark 07103
    Med Phys 21:1921-6. 1994
    ..This suggests that the Auger electrons emitted in the decay of 99mTc are not capable of causing extreme toxicity in vivo. These results provide further support for 99mTc as the radionuclide of choice for imaging in nuclear medicine...
  11. ncbi request reprint Radioprotection by DMSO against the biological effects of incorporated radionuclides in vivo--Comparison with other radioprotectors and evidence for indirect action of Auger electrons
    S M Goddu
    Department of Radiology, New Jersey Medical School, University of Medicine and Dentistry of New Jersey, Newark 07103, USA
    Acta Oncol 35:901-7. 1996
    ..The present findings provide supporting evidence that the mechanism responsible for the extreme biological damage caused by DNA-bound Auger emitters is largely radical mediated and therefore indirect in nature...
  12. pmc Free radical-initiated and gap junction-mediated bystander effect due to nonuniform distribution of incorporated radioactivity in a three-dimensional tissue culture model
    A Bishayee
    Division of Radiation Research, Department of Radiology, University of Medicine and Dentistry of New Jersey, 07103, USA
    Radiat Res 155:335-44. 2001
    ..Furthermore, at least a part of these bystander effects are initiated by free radicals and are likely to be mediated by gap junctional intercellular communication...
  13. pmc Radiation protection by cysteamine against the lethal effects of intracellularly localized Auger electron, alpha- and beta-particle emitting radionuclides
    A Bishayee
    Department of Radiology, New Jersey Medical School, University of Medicine and Dentistry of New Jersey, Newark 07103, USA
    Acta Oncol 39:713-20. 2000
    ..1, respectively. MEA provides more protection against indirect than direct effects of ionizing radiation, and indirect effects play a role in the radiotoxicity of Auger electron emitters incorporated into the DNA of mammalian cells...
  14. pmc Log normal distribution of cellular uptake of radioactivity: implications for biologic responses to radiopharmaceuticals
    Prasad V S V Neti
    Division of Radiation Research, Department of Radiology, New Jersey Medical School, University of Medicine and Dentistry of New Jersey, Newark, New Jersey, USA
    J Nucl Med 47:1049-58. 2006
    ..In the present study, the distribution of activity per cell is experimentally determined and its implications for predicting biologic response are examined...
  15. ncbi request reprint Calculation of equivalent dose for Auger electron emitting radionuclides distributed in human organs
    S M Goddu
    Department of Radiology, University of Medicine and Dentistry of New Jersey, New Jersey Medical School, Newark 07103, USA
    Acta Oncol 35:909-16. 1996
    ..The results show an increase in the mean equivalent dose for Auger electron emitters when a significant fraction of the organ activity localizes in the DNA...
  16. ncbi request reprint Marrow-sparing effects of 117mSn(4+)diethylenetriaminepentaacetic acid for radionuclide therapy of bone cancer
    A Bishayee
    Department of Radiology, University of Medicine and Dentistry of New Jersey New Jersey Medical School, Newark 07103, USA
    J Nucl Med 41:2043-50. 2000
    ..A recent study on 47 patients using the short-range CE emitter 117mSn(4+)diethylenetriaminepentaacetic acid (117mSn(4+)DTPA) supports this hypothesis. The hypothesis is now tested using 117mSn(4+)DTPA in a mouse femur model...
  17. ncbi request reprint Biologic dosimetry of bone marrow: induction of micronuclei in reticulocytes after exposure to 32P and 90Y
    M Lenarczyk
    Department of Radiology, University of Medicine and Dentistry of New Jersey-New Jersey Medical School, Newark 07103, USA
    J Nucl Med 42:162-9. 2001
    ..CONCLUSION: Micronuclei in peripheral blood reticulocytes can be used as a noninvasive biologic dosimeter for measuring absorbed dose rate and absorbed dose to bone marrow from incorporated radionuclides...
  18. pmc Concomitant quantification of targeted drug delivery and biological response in individual cells
    Massimo Pinto
    University of Medicine and Dentistry of New Jersey, Newark, NJ 07101, USA
    Biotechniques 43:64, 66-71. 2007
    ..The overall approach presented herein may be useful in the context of evaluating responses to targeted drug delivery...
  19. pmc Biological response to nonuniform distributions of (210)Po in multicellular clusters
    Prasad V S V Neti
    Division of Radiation Research, Department of Radiology, New Jersey Medical School, University of Medicine and Dentistry of New Jersey, Newark, NJ 07103, USA
    Radiat Res 168:332-40. 2007
    ..Neither the mean cluster absorbed dose nor a semi-empirical multicellular dosimetry approach could accurately predict the lethal effects of (210)Po-citrate...
  20. pmc A multi-port low-fluence alpha-particle irradiator: fabrication, testing and benchmark radiobiological studies
    Prasad V S V Neti
    Department of Radiology, Division of Radiation Research, New Jersey Medical School, Newark, New Jersey 07103, USA
    Radiat Res 161:732-8. 2004
    ..Clonogenic cell survival experiments with AG1522 human fibroblasts indicate that the RBE of the alpha particles compared to (137)Cs gamma rays is about 7.6 for this biological end point...
  21. pmc Investigation of adaptive responses in bystander cells in 3D cultures containing tritium-labeled and unlabeled normal human fibroblasts
    Massimo Pinto
    Department of Radiology, Division of Radiation Research, UMDNJ New Jersey Medical School Cancer Center, Newark, New Jersey 07103, USA
    Radiat Res 174:216-27. 2010
    ..Higher dose rates and/or higher LET may be required to observe stressful bystander effects in this experimental system, whereas lower dose rates and challenge doses may be required to detect adaptive bystander responses...
  22. ncbi request reprint Adaptive responses to low-dose/low-dose-rate gamma rays in normal human fibroblasts: the role of growth architecture and oxidative metabolism
    Sonia M De Toledo
    Department of Radiology, UMDNJ New Jersey Medical School, Newark, New Jersey 07101, USA
    Radiat Res 166:849-57. 2006
    ..Expression of connexin 43, a constitutive protein of gap junctions, and the G(1) checkpoint were more sensitive to regulation by gamma rays in cells maintained in a three-dimensional than in a two-dimensional configuration...
  23. pmc Lognormal distribution of cellular uptake of radioactivity: statistical analysis of alpha-particle track autoradiography
    Prasad V S V Neti
    Division of Radiation Research, Department of Radiology, New Jersey Medical School, University of Medicine and Dentistry of New Jersey, Newark, New Jersey 07103, USA
    J Nucl Med 49:1009-16. 2008
    ..2006;47:1049-1058) with the aid of autoradiography. To ascertain the influence of Poisson statistics on the interpretation of the autoradiographic data, the present work reports on a detailed statistical analysis of these earlier data...
  24. ncbi request reprint Flow cytometry as a strategy to study radiation-induced bystander effects in co-culture systems
    Bogdan I Gerashchenko
    Department of Radiology, University of Medicine and Dentistry of New Jersey, New Jersey Medical School, Newark, New Jersey 07103 2714, USA
    Cytometry A 54:1-7. 2003
    ..Qualitative and quantitative assessment of bystander effects requires quick and reliable methodologies. The present work uses a flow cytometric approach to study proliferation of bystander cells co-cultured with irradiated cells...
  25. ncbi request reprint Characterization of cell-cycle progression and growth of WB-F344 normal rat liver epithelial cells following gamma-ray exposure
    Bogdan I Gerashchenko
    Department of Radiology, University of Medicine and Dentistry of New Jersey, New Jersey Medical School, Newark, NJ 07103, USA
    Cytometry A 61:134-41. 2004
    ..Here, the distribution of phases in the cell-cycle and the proliferation ability of WB-F344 cells are characterized at various time points after the cells have been irradiated with different doses of gamma-rays...
  26. ncbi request reprint Cell proximity is a prerequisite for the proliferative response of bystander cells co-cultured with cells irradiated with gamma-rays
    Bogdan I Gerashchenko
    Department of Radiology, University of Medicine and Dentistry of New Jersey, New Jersey Medical School, Newark, New Jersey 07103 2714, USA
    Cytometry A 56:71-80. 2003
    ....
  27. pmc Radiation-induced reductions in transporter mRNA levels parallel reductions in intestinal sugar transport
    Marjolaine Roche
    Department of Pharmacology and Physiology, New Jersey Medical School, NJ, USA
    Am J Physiol Regul Integr Comp Physiol 298:R173-82. 2010
    ..In conclusion, the effect of radiation may be posttranscriptional, and radiation-damaged intestines can still respond to dietary stimuli...
  28. pmc Proliferative response of bystander cells adjacent to cells with incorporated radioactivity
    Bogdan I Gerashchenko
    Department of Radiology, University of Medicine and Dentistry of New Jersey, New Jersey Medical School, Newark, New Jersey 07103, USA
    Cytometry A 60:155-64. 2004
    ..The aim of the current work is to investigate the possible proliferative bystander effects caused by intracellular irradiation with incorporated radionuclides, specifically the short-range beta particle emitter, tritium ((3)H)...
  29. ncbi request reprint Bystander cell proliferation is modulated by the number of adjacent cells that were exposed to ionizing radiation
    Bogdan I Gerashchenko
    Department of Radiology, University of Medicine and Dentistry of New Jersey, New Jersey Medical School, Newark, New Jersey 07103 2714, USA
    Cytometry A 66:62-70. 2005
    ....
  30. ncbi request reprint Does metabolic radiolabeling stimulate the stress response? Gene expression profiling reveals differential cellular responses to internal beta vs. external gamma radiation
    Nicholas F Marko
    Department of Biochemistry and Molecular Biology, The George Washington University Medical Center, 2300 Eye St, N W, Washington, DC 20037, USA
    FASEB J 17:1470-86. 2003
    ....
  31. ncbi request reprint Susceptibility of the human pathogenic fungi Cryptococcus neoformans and Histoplasma capsulatum to gamma-radiation versus radioimmunotherapy with alpha- and beta-emitting radioisotopes
    Ekaterina Dadachova
    Department of Nuclear Medicine, Albert Einstein College of Medicine, 1695A Eastchester Road, Bronx, NY 10461, USA
    J Nucl Med 45:313-20. 2004
    ....

Research Grants1

  1. EFFECTS OF NONUNIFORM DISTRIBUTIONS OF RADIOACTIVITY
    Roger Howell; Fiscal Year: 2009
    ..Finally, to initiate transition of our multicellular dosimetry approach to in vivo, we will carry out bystander studies in mouse testis. ..