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Open Access Publications from the University of California

Scholarly Works (3 results)

  • Article
  • Peer Reviewed
UC Irvine Previously Published Works (2011)
Background: NEK1, the first mammalian ortholog of the fungal protein kinase never-in-mitosis A (NIMA), is involved early in the DNA damage sensing/repair pathway. A defect in DNA repair in NEK1-deficient cells is suggested by persistence of DNA double strand breaks after low dose ionizing radiation (IR). NEK1-deficient cells also fail to activate the checkpoint kinases CHK1 and CHK2, and fail to arrest properly at G1/S or G2/M-phase checkpoints after DNA damage. Results: We show here that NEK1-deficient cells suffer major errors in mitotic chromosome segregation and cytokinesis, and become aneuploid. These NEK1-deficient cells transform, acquire the ability to grow in anchorageindependent conditions, and form tumors when injected into syngeneic mice. Genomic instability is also manifest in NEK1 +/- mice, which late in life develop lymphomas with a much higher incidence than wild type littermates. Conclusion: NEK1 is required for the maintenance of genome stability by acting at multiple junctures, including control of chromosome stability.
    Cover page: Mutation of NIMA-related kinase 1 (NEK1) leads to chromosome instabilityCreative Commons 'BY' version 4.0 license
    • Article
    • Peer Reviewed
    UCLA Previously Published Works (2016)

    Purpose

    To investigate the relationship between abdominal chemoradiation (CRT) for locally advanced cancers and bone mineral density (BMD) reduction in the vertebral spine.

    Materials and methods

    Data from 272 patients who underwent abdominal radiation therapy from January 1997 to May 2015 were retrospectively reviewed. Forty-two patients received computed tomography (CT) scans of the abdomen prior to initiation and at least twice after radiation therapy. Bone attenuation (in Hounsfield unit) (HU) measurements were collected for each vertebral level from T7 to L5 using sagittal CT images. Radiation point dose was obtained at each mid-vertebral body from the radiation treatment plan. Percent change in bone attenuation (Δ%HU) between baseline and post-radiation therapy were computed for each vertebral body. The Δ%HU was compared against radiation dose using Pearson's linear correlation.

    Results

    Abdominal radiotherapy caused significant reduction in vertebral BMD as measured by HU. Patients who received only chemotherapy did not show changes in their BMD in this study. The Δ%HU was significantly correlated with the radiation point dose to the vertebral body (R=-0.472, P<0.001) within 4-8 months following RT. The same relationship persisted in subsequent follow up scans 9 months following RT (R=-0.578, P<0.001). Based on the result of linear regression, 5 Gy, 15 Gy, 25 Gy, 35 Gy, and 45 Gy caused 21.7%, 31.1%, 40.5%, 49.9%, and 59.3% decrease in HU following RT, respectively. Our generalized linear model showed that pre-RT HU had a positive effect (β=0.830) on determining post-RT HU, while number of months post RT (β=-0.213) and radiation point dose (β=-1.475) had a negative effect. A comparison of the predicted versus actual HU showed significant correlation (R=0.883, P<0.001) with the slope of the best linear fit=0.81. Our model's predicted HU were within ±20 HU of the actual value in 53% of cases, 70% of the predictions were within ±30 HU, 81% were within ±40 HU, and 90% were within ±50 HU of the actual post-RT HU. Four of 42 patients were found to have vertebral body compression fractures in the field of radiation.

    Conclusions

    Patients who receive abdominal chemoradiation develop significant BMD loss in the thoracic and lumbar vertebrae. Treatment-related BMD loss may contribute to the development of vertebral compression fractures. A predictive model for post-CRT BMD changes may inform bone protective strategies in patients planned for abdominal CRT.
      Cover page: Bone mineral density loss in thoracic and lumbar vertebrae following radiation for abdominal cancers
      • Article
      • Peer Reviewed
      Plexus (2014)

      Plexus is a student-organized publication that showcases artwork by UCI School of Medicine students, physicians, faculty, staff and patients. True to its name, PLEXUS aspires to connect those who seek to heal and to be healed through the unifying language of art.

      This year, the Plexus team is excited to introduce some ‘firsts’ - a theme, the traveling Plexus exhibit, a separate Art for the Soul section and inclusion of performance arts. You were invited to embody the theme of ‘Equilibrium & Transformation’ in your art and what a response! Thank you for sharing your wealth of emotion and perspective. Due to an overwhelming number of requests to display Plexus at events last year, we have produced our own moveable feast of 5-10 of our most prominent pieces from Plexus 2013 and displayed it during Solidarity Day 2014 and at Irvine Hall, and plan to display an updated version at UCI Medical Center during various departmental events this year. We have also highlighted work created by cancer survivors through the Art for the Soul program in a separate section and have added a ‘Performance’ section on the Plexus website to respond to the community’s passion for dance and drama.

      Congratulations to this year’s winners of the medical student writing competition! 1st: Anjali Hari, MS2 ‘Maya’ 2nd: Jiwon Shin, MS1 ‘The Remnants’ and 3rd: Lorianne Burns, MS3 ‘Conversation Unspoken’.

      Thank you to our wonderful Editors who helped bring all the changes to fruition, and for bringing thoughtful criticism and inspiration to our creative vision. We would like to thank Dean Clayman for sponsoring the traveling Plexus exhibit. We would like to give special thanks to our faculty advisor, Dr. Johanna Shapiro and Dr. Ellen Peterson, Associate Dean of Admissions and Outreach. This book would not have been possible without your support.

      We hope you enjoy PLEXUS 2014. Bon voyage!

      Editors-In-Chief: Nabila Haque, Esther Jun

      Digital Editor-In-Chief: Adam Truong

      Creative Writing: Jacqueline Kurth, Christy Tabit

      Layout, Design & Visuals: Ben Nguyen, Kevin Gustafson

      Audio & Performance: Jessica Galant, Evelyn Hoover, Katherine Stern

      Marketing And Outreach: Avinash Chaurasia, Jiwon Helen Shin

      Website Design: Neil Saez

      1st Place Winner of PLEXUS Student Writing Competition made possible by UCISOM Humanities Dept.: Anjali Hari

      2nd Place Winner; Jiwon Helen Shin

      3rd Place Winner: Lorianne Burns

      To contribute to Plexus or to request the Plexus exhibit at your event, please send email plexusjournal@gmail.com. We look forward to hearing from you!

        Cover page: Plexus 2014: <em>Equilibrium &amp; Transformation</em>Creative Commons 'BY' version 4.0 license
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