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Open Access Publications from the University of California

Scholarly Works (20 results)

  • Article
  • Peer Reviewed
UC Irvine Previously Published Works (2010)
Purpose: Milner & Goodale, 1995, propose that visual processing splits into a ventral, "what" stream devoted to conscious recognition processes and a dorsal, "how" stream mediating motor control. Whereas the ventral stream receives input from both the magnocellular and parvocellular pathways, the dorsal stream receives only magnocellular input, suggesting that the "how" system may lack chromatic sensitivity. Here we assess the relative sensitivities to luminance versus chromatic variations in distinct tasks designed to selectively engage these two processing streams. Method: Taskwhat required the subject to register with a buttonpress the orientation (right, left, up or down) of a foveal isoceles triangle, briefly flashed, then masked. Taskhow required the subject to touch with a stylus the tip of the most acute angle of an isoceles triangle presented randomly in one of 4 orientations at one of 4 parafoveal locations. Each task used (i) equiluminant green targets varying in saturation, and (ii) isochromatic gray targets varying in luminance. Psychometric functions of green-target saturation and of gray-target luminance were obtained in Taskwhat. In Taskhow we measured movement duration and endpoint accuracy. Results: For saturation Green(p) and luminance Gray(p) yielding identical success rate p in Taskwhat, Green(p) targets yielded movement trajectories in Taskhow that were significantly slower and/or less accurate than Gray(p) targets. Conclusions: The process mediating performance in Taskwhat is relatively more sensitive to chromatic (vs. luminance) variations than the process mediating performance of Taskhow, supporting the dual claims that (i) Taskwhat and Taskhow selectively activate the "what" and "how" systems, and (ii) the "what" system is relatively more sensitive to chromatic variations than the " how" system.
    Cover page: Psychophysical dissociation of "how" and "what" tasks in normal participantsCreative Commons 'BY' version 4.0 license
    • Article
    • Peer Reviewed
    Postprints from the CTCRE (2006)

    In this article we present communication theory as a conceptual framework for conducting documents research on tobacco advertising strategies, and we discuss two methods for analysing advertisements: semiotics and content analysis. We provide concrete examples of how we have used tobacco industry documents archives and tobacco advertisement collections iteratively in our research to yield a synergistic analysis of these two complementary data sources. Tobacco promotion researchers should consider adopting these theoretical and methodological approaches.

      Cover page: Every document and picture tells a story: using internal corporate document reviews, semiotics, and content analysis to assess tobacco advertising.
      • Article
      • Peer Reviewed
      UC Davis Previously Published Works (1995)
      One or more brief periods of ischemia, termed preconditioning, dramatically limits infarct size and reduces intracellular acidosis during subsequent ischemia, potentially via enhanced sarcolemmal proton efflux mechanisms. To test the hypothesis that preconditioning increases the functional activity of sodium-dependent proton efflux pathways, isolated rat hearts were subjected to 30 min of global ischemia with or without preconditioning. Intracellular sodium (Nai) was assessed using 23Na magnetic resonance spectroscopy, and the activity of the Na-H exchanger and Na-K-2Cl cotransporter was measured by transiently exposing the hearts to an acid load (NH4Cl washout). Creatine kinase release was reduced by greater than 60% in the preconditioned hearts (P < 0.05) and was associated with improved functional recovery on reperfusion. Preconditioning increased Nai by 6.24 +/- 2.04 U, resulting in a significantly higher level of Nai before ischemia than in the control hearts. Nai increased significantly at the onset of ischemia (8.48 +/- 1.21 vs. 2.57 +/- 0.81 U, preconditioned vs. control hearts; P < 0.01). Preconditioning did not reduce Nai accumulation during ischemia, but the decline in Nai during the first 5 min of reperfusion was significantly greater in the preconditioned than in the control hearts (13.48 +/- 1.73 vs. 2.54 +/- 0.41 U; P < 0.001). Exposure of preconditioned hearts to ethylisopropylamiloride or bumetanide in the last reperfusion period limited in the increase in Nai during ischemia and reduced the beneficial effects of preconditioning. After the NH4Cl prepulse, preconditioned hearts acidified significantly more than control hearts and had significantly more rapid recovery of pH (preconditioned, delta pH = 0.35 +/- 0.04 U over 5 min; control, delta pH = 0.15 +/- 0.02 U over 5 min). This rapid pH recovery was not affected by inhibition of the Na-K-2Cl cotransporter but was abolished by inhibition of the Na-H exchanger. These results demonstrate that preconditioning alters the kinetics of Nai accumulation during global ischemia as well as proton transport after NH4Cl washout. These observations are consistent with stimulation of the Na-K-2Cl cotransporter and Na-H exchanger by preconditioning.
        Cover page: Ischemic preconditioning stimulates sodium and proton transport in isolated rat hearts.
        • Article
        • Peer Reviewed
        Recent Work (2004)

        Many materials and electronics need to be tested for the radiation environment expected at linear colliders (LC) where the accelerator and detectors will be subjected to large fluences of hadrons, leptons and gamma’s over their life. Examples are NdFeB magnets considered for the damping rings and final focus, electronic and electro-optical devices to be utilized in detector readout and accelerator controls and CCDs required for the vertex detector. Effects of gamma’s on many materials have been presented and our understanding of the situation for rare earth permanent magnets at the Particle Accelerator Conference 2003. Here we give first measurements of the fast neutron, stepped doses at the UC Davis McClellan Nuclear Reactor Center (UCD/MNRC) together with the induced radioactivities. Damage appears to be proportional to the distances between the operating point and Hci.

          Cover page: Radiation Damage Studies with Hadrons on Materials and Electronics
          • Article
          Recent Work (2007)

          Many materials and electronics need to be tested for the radiation environment expected at linear colliders (LC) to improve reliability and longevity since both accelerator and detectors will be subjected to large fluences of hadrons, leptons and gammas. Examples include NdFeB magnets, considered for the damping rings, injection and extraction lines and final focus, electronic and electro-optic devices to be utilized in detector readout, accelerator controls and the CCDs required for the vertex detector, as well as high and low temperature superconducting materials (LTSMs) because some magnets will be superconducting. Our first measurements of fast neutron, stepped doses at the UC Davis McClellan Nuclear Reactor Center (UCD MNRC) were presented for NdFeB materials at EPAC04 where the damage appeared proportional to the distances between the effective operating point and Hc. We have extended those doses, included other manufacturer's samples and measured induced radioactivities. We have also added L and HTSMs as well as a variety of relevant semiconductor and electro-optic materials including PBG fiber that we studied previously only with gamma rays.

            Cover page: Fast Neutron Radioactivity and Damage Studies on Materials
            • Article
            • Peer Reviewed
            Recent Work (2005)

            Many materials and electronics need to be tested for the radiation environment expected at linear colliders (LC) since both accelerator and detectors will be subjected to large fluences of hadrons, leptons and gamma’s over the life of the facility. While the linacs will be superconducting, there are still many uses for NdFeB in the damping rings, injection and extraction lines and final focus. Our understanding of the situation for rare earth, permanent magnet materials was presented at the Particle Accelerator Conference 2003. Our first measurements of fast neutron, stepped doses at the UC Davis McClellan Nuclear Reactor Center (UCD MNRC) were presented at the European Particle Accelerator Conference 2004. We have extended the doses, included other manufacturer’s samples, and measured induced radioactivities which are discussed in detail.

              Cover page: Fast neutron Damage Studies on NdFeB Materials
              • Article
              • Peer Reviewed
              UCLA Previously Published Works (2016)
              The RANO criteria have not been assessed using outcome data from prospective trials. We examined the radiologic data of patients with recurrent glioblastoma from the randomized phase II trial (AVF3708g) to determine the effect of including T2/FLAIR evaluation as per RANO criteria on measurements of objective response rates (ORRs) and progression-free survival (PFS) compared with assessment based on contrast enhancement (Macdonald criteria).The ORRs and median PFS were determined using the RANO criteria and compared with those obtained using the Macdonald criteria. Landmark analyses were performed at 2, 4, and 6 months, and Cox proportional hazard models were used to determine the associations between OR and progression with subsequent survival.The ORRs were 0.331 [95% confidence interval (CI), 0.260-0.409] and 0.393 (95% CI, 0.317-0.472) by RANO and Macdonald criteria, respectively (P < 0.0001). The median PFS was 4.6 months (95% CI, 4.1-5.5) using RANO criteria, compared with 6.4 months (95% CI, 5.5-7.1) as determined by Macdonald criteria (P = 0.01). At 2-, 4-, and 6-month landmarks, both OR status and PFS determined by either RANO or Macdonald criteria were predictive of overall survival [OS; hazard ratios for 4-month landmark (OR HR = 1.93, P = 0.0012; PFS HR, 4.23, P < 0.0001)].The inclusion of T2/FLAIR assessment resulted in statistically significant differences in median PFS and ORRs compared with assessment of solely enhancing tumor (Macdonald criteria), although OR and PFS determined by both RANO and Macdonald criteria correlated with OS.
                Cover page: The Impact of T2/FLAIR Evaluation per RANO Criteria on Response Assessment of Recurrent Glioblastoma Patients Treated with Bevacizumab
                • Article
                Lawrence Berkeley National Laboratory (2001)
                  Cover page: The next linear collider damping ring complex
                  • Article
                  • Peer Reviewed
                  UC San Francisco Previously Published Works (2017)
                  Abstract

                  BACKGROUND

                  Heat shock protein vaccines can be used to stimulate anti-tumor immune responses. An autologous vaccine (HSPPC-96) generated from patient resected tumors has been previously studied in single arm phase I/II trials for newly diagnosed and recurrent GBM. Based on promising survival in these studies, a randomized, multi-centered phase II trial of HSPPC-96 for recurrent GBM compared to bevacizumab was undertaken (NCT01814813).

                  METHODS

                  Patients with 1st/2nd recurrence of resectable GBM were enrolled and underwent surgery with generation of HSPPC-96 from autologous tumors. Post-operative eligibility included a volumetric extent of resection ≥90% (by central review) and sufficient tumor to generate a minimum of 4 vaccine doses. Patients were randomized (1:1:1) to receive HSPPC-96 vaccine followed by bevacizumab at subsequent progression vs. concurrent HSPPC-96 vaccine and bevacizumab vs. bevacizumab alone. The primary endpoint was overall survival (OS) aiming to detect a 36% reduction in HR with 85% power and alpha=0.1 for pooled HSPPC-96 groups vs. bevacizumab alone. Planned enrollment was 165 patients (n=55/arm). An interim analysis was pre-planned at 50% of events (65 deaths). Secondary endpoints included progression-free survival and adverse events.

                  RESULTS

                  At final analysis, 90 patients were enrolled with a distribution of 29:30:31. The study was terminated for futility after the interim analysis. In the intention to treat population, OS for the HSPPC-96 treated groups was 7.5 vs. 10.7 months for bevacizumab alone (HR=2.06 [95% CI 1.18–3.60], p=0.008). Among patients treated per protocol (n=73), OS for HSPPC-96 patients was 8.6 vs. 12.3 months (HR=1.99 [95% CI 1.03–3.81], p=0.03). Trends were similar for progression-free survival between groups. HSPPC-96 toxicity was well tolerated with no attributable serious adverse events.

                  CONCLUSIONS

                  The study failed to demonstrate a survival benefit for patients treated with HSPPC-96 alone or in combination with bevacizumab compared to bevacizumab alone. Correlative analyses are ongoing. SUPPORT: U10CA180882, U10CA180821, U10CA180868, U24CA196171.
                    Cover page: ATIM-14. ALLIANCE A071101: A&nbsp;PHASE II RANDOMIZED TRIAL COMPARING THE EFFICACY OF HEAT SHOCK PROTEIN PEPTIDE COMPLEX-96 (HSPPC-96) VACCINE GIVEN WITH BEVACIZUMAB VERSUS BEVACIZUMAB ALONE IN THE TREATMENT OF SURGICALLY RESECTABLE RECURRENT GLIOBLASTOMA
                    • Article
                    • Peer Reviewed
                    UC San Diego Previously Published Works (2017)

                    Background

                    Whole brain radiotherapy (WBRT) is the standard of care to improve intracranial control following resection of brain metastasis. However, stereotactic radiosurgery (SRS) to the surgical cavity is widely used in an attempt to reduce cognitive toxicity, despite the absence of high-level comparative data substantiating efficacy in the postoperative setting. We aimed to establish the effect of SRS on survival and cognitive outcomes compared with WBRT in patients with resected brain metastasis.

                    Methods

                    In this randomised, controlled, phase 3 trial, adult patients (aged 18 years or older) from 48 institutions in the USA and Canada with one resected brain metastasis and a resection cavity less than 5·0 cm in maximal extent were randomly assigned (1:1) to either postoperative SRS (12-20 Gy single fraction with dose determined by surgical cavity volume) or WBRT (30 Gy in ten daily fractions or 37·5 Gy in 15 daily fractions of 2·5 Gy; fractionation schedule predetermined for all patients at treating centre). We randomised patients using a dynamic allocation strategy with stratification factors of age, duration of extracranial disease control, number of brain metastases, histology, maximal resection cavity diameter, and treatment centre. Patients and investigators were not masked to treatment allocation. The co-primary endpoints were cognitive-deterioration-free survival and overall survival, and analyses were done by intention to treat. We report the final analysis. This trial is registered with ClinicalTrials.gov, number NCT01372774.

                    Findings

                    Between Nov 10, 2011, and Nov 16, 2015, 194 patients were enrolled and randomly assigned to SRS (98 patients) or WBRT (96 patients). Median follow-up was 11·1 months (IQR 5·1-18·0). Cognitive-deterioration-free survival was longer in patients assigned to SRS (median 3·7 months [95% CI 3·45-5·06], 93 events) than in patients assigned to WBRT (median 3·0 months [2·86-3·25], 93 events; hazard ratio [HR] 0·47 [95% CI 0·35-0·63]; p<0·0001), and cognitive deterioration at 6 months was less frequent in patients who received SRS than those who received WBRT (28 [52%] of 54 evaluable patients assigned to SRS vs 41 [85%] of 48 evaluable patients assigned to WBRT; difference -33·6% [95% CI -45·3 to -21·8], p<0·00031). Median overall survival was 12·2 months (95% CI 9·7-16·0, 69 deaths) for SRS and 11·6 months (9·9-18·0, 67 deaths) for WBRT (HR 1·07 [95% CI 0·76-1·50]; p=0·70). The most common grade 3 or 4 adverse events reported with a relative frequency greater than 4% were hearing impairment (three [3%] of 93 patients in the SRS group vs eight [9%] of 92 patients in the WBRT group) and cognitive disturbance (three [3%] vs five [5%]). There were no treatment-related deaths.

                    Interpretation

                    Decline in cognitive function was more frequent with WBRT than with SRS and there was no difference in overall survival between the treatment groups. After resection of a brain metastasis, SRS radiosurgery should be considered one of the standards of care as a less toxic alternative to WBRT for this patient population.

                    Funding

                    National Cancer Institute.
                      Cover page: Postoperative stereotactic radiosurgery compared with whole brain radiotherapy for resected metastatic brain disease (NCCTG N107C/CEC·3): a multicentre, randomised, controlled, phase 3 trial
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