Biochemical and Biophysical Research Communications, 1989
Chromatography of a DNA polymerase preparation from mitochondria of Saccharomyces cerevisiae on D... more Chromatography of a DNA polymerase preparation from mitochondria of Saccharomyces cerevisiae on DNA-cellulose column, using Tris-HCl (pH 7.5) buffer containing 0.6 M NaCl as eluent, was found to yield a fraction exhibiting DNA primase-like activity free of DNA polymerase. This fraction could support the synthesis of 12-15 residue-long oligoribonucleotides on single-stranded natural or synthetic DNA templates. The oligoribonucleotides could be further elongated by incorporation of deoxyribonucleotides in the presence of Klenow fragment.
Biochemical and Biophysical Research Communications, 1983
The effect of desaspidin, ortho-desaspidin, flavaspidic acid, nor-flavaspidic acid and desaspidin... more The effect of desaspidin, ortho-desaspidin, flavaspidic acid, nor-flavaspidic acid and desaspidinol on respiration and oxidative phosphorylation in rat liver mitochondria was studied.
International Journal of Radiation Oncology Biology Physics, 2007
Purpose/Objective(s): Presently RT and AS is considered standard of care in HR PC. Recent trials ... more Purpose/Objective(s): Presently RT and AS is considered standard of care in HR PC. Recent trials with RT and AS show a .15-20% biochemical failure (BF) rate in HR PC. In RTOG 85-31 and 86-10, the local failure (LF), distant metastases (DM) and overall survival (OS) rates after RT and long term AS were 30%, 52% and 51% respectively. The Dutch DHT study showed improved local control (LC) and OS with DHT and RT in other pelvic tumors like cervical cancer. A previous Duke University study enrolled 18 patients with HR PC treated with DHT and RT without AS, and their 3-yr LC, DM-free survival and disease-free survival (DFS) rates were 93%, 68%, and 25% respectively. Patients with HR PC were enrolled in this FDA and IRB approved phase I/II protocol to study the feasibility, tolerance and efficacy of DHT with RT and AS. Materials/Methods: Between 1999 and 2002, 23 patients (median age 61 yrs) with HR PC were enrolled in this Northwestern University phase I/II study. HR PC patients had one or more of the following factors: PSA .20 (10 pts), Gleason's score .7 (20 pts), T3/T4 tumors (16 pts) or pelvic node metastases (4 pts). All patients received AS with RT and adjuvant AS for 1-2 years. The median RT dose was 70.2 Gy to the prostate and 45 Gy to the pelvic nodes. External DHT was delivered weekly or twice weekly 72 hrs apart during RT using a BSD-2000 Sigma-60 applicator. Vital signs were monitored every five minutes according to protocol. The median number of DHT treatments was 10 (2-10). The aim was to achieve and maintain a minimum temperature of 42 C in a rectally placed temperature probe for 45-60 minutes. DHT tolerance was graded per protocol, acute and late toxicity was graded per CTCAE version 3.0. Results: The frequency of heating was 72 MHz with an applied power in the range of 400 to 900 watts. Cumulative average thermal dose (TD at 42.5 C) of 84.1 (± 63.7) minutes was achieved in an average of 9.2 (± 2.1) number of treatments. Average maximum temperature was 41.9 C (± 0.8). DHT was generally well tolerated with no new systemic or cardiac symptoms during or after DHT. The majority of patients (83%) received 10 DHT treatments. 1 patient refused further DHT after 2 sessions and 1 patient received 4 DHT treatments due to poor tolerance. 2 patients (9%) developed acute grade 2 dermatitis during DHT and RT. There were no acute or late grade 3-4 skin toxicity; however, 2 patients developed transient fat necrosis. 1 patient developed late grade 3 GU toxicity (cystitis). 3 patients (14%) developed late grade 3 rectal complications (bleeding) that were controlled with 1-2 sessions of laser therapy. No patient developed any late grade 4 GU or rectal toxicity. The median follow-up was 61.5 months (range 6-79). The 5 year OS, biochemical DFS, LC, and DM free-survival rates were 75%, 69%, 94% and 80%, respectively. Conclusions: This is the first report to describe the tolerance and efficacy of DHT, RT and AS in HR PC. This report demonstrates that this treatment regimen was well tolerated with minimal acute and late-toxicity. The OS and DFS rates of 70-75% are encouraging. LC rates of 94% in this group of patients with HR PC points to a potential synergy between DHT, RT, and AS. The predominant pattern of failure was distant metastases (20%). Future studies incorporating chemotherapy in addition to DHT, RT, and AS in HR PC are planned.
International Journal of Radiation Oncology Biology Physics, 2007
Purpose/Objective(s): CBCT registration to a reference image is one of the emerging tools used fo... more Purpose/Objective(s): CBCT registration to a reference image is one of the emerging tools used for prostate localization. This preliminary study compares fiducial marker co-registration to two methods of CBCT image registration utilizing Varian On-Board Imaging System TM (OBI) and in-house automatic fusion software. Materials/Methods: Seventy CBCT scans from two localized prostate cancer patients were used for this study. Both patients were implanted with three 1.2x3 mm soft tissue markers. Each patient was educated regarding a bowel regimen to facilitate an empty rectum prior to simulation and daily treatment. For daily treatments, patients were initially aligned to skin marks. On-line automatic image fusion between CBCT and simulation CT (Sim-CT) was performed using OBI version 1.3. Offsets were recorded in three translational degrees of freedom. Prior to treatment, fiducial marker co-registration was performed using two KV-orthogonal images and offsets were recorded and applied to treatment couch, defining the treatment position. Inter-fiducial distances (n= 450) were measured and recorded to check for seed migration. In an offline manner, automatic in-house registration, utilizing the uphill simplex, gradient correlation and mutual information similarity measures, was performed between Sim-CT and CBCT using the prostate as the region of interest. Fiducial marker data, considered the control, was compared to the two CBCT image registration methods. Mismatch between fiducial marker and OBI (Fd-OBI) and mismatch between fiducial marker and in-house fusion (Fd-house) was measured. Mismatch in the LR, AP, CC directions was reported and percentage of observations falling between 1 and 7 mm between the two registration methods was tabulated. Results: Inter-fiducial distances showed minimal seed migration with mean of <1±0.7 mm. Comparing the two methods of registration, Fd-house showed a mean mismatch of 1.0± 0.65, 1.0±0.96 and 1±1.07 mm in the LR, AP, and CC directions respectively. Comparable data was observed for the Fd-OBI data with mean of 1.0±0.74, 2.0±1.28, and 2.0±1.69 mm in the LR, AP, and CC directions respectively. Examining the percentage of mismatch observations (n= 414) the following data was observed: Conclusions: While the technical aspects of fiducial marker co-registration are attractive, invasiveness and seed migration can be noted as potential drawbacks. The phenomenon of seed migration was not observed in our study justifying the use of fiducial marker as a good control. Our in house automatic fusion software in conjunction with CBCT images showed a superior correlation to the fiducial markers and can offer an attractive noninvasive tool for improving prostate localization.
[bold Purpose:] To assess the accuracy and dosimetric implications of multi‐modality, online imag... more [bold Purpose:] To assess the accuracy and dosimetric implications of multi‐modality, online image‐guided localization methods, including intra‐modality 3D prostate ultrasound, cone beam CT (CBCT), implanted prostate markers and Calypso 4D localization for patients ...
International Journal of Radiation Oncology Biology Physics, 2010
To evaluate different similarity metrics (SM) using natural calcifications and observation-based ... more To evaluate different similarity metrics (SM) using natural calcifications and observation-based measures to determine the most accurate prostate and seminal vesicle localization on daily cone-beam CT (CBCT) images. CBCT images of 29 patients were retrospectively analyzed; 14 patients with prostate calcifications (calcification data set) and 15 patients without calcifications (no-calcification data set). Three groups of test registrations were performed. Test 1: 70 CT/CBCT pairs from calcification dataset were registered using 17 SMs (6,580 registrations) and compared using the calcification mismatch error as an endpoint. Test 2: Using the four best SMs from Test 1, 75 CT/CBCT pairs in the no-calcification data set were registered (300 registrations). Accuracy of contour overlays was ranked visually. Test 3: For the best SM from Tests 1 and 2, accuracy was estimated using 356 CT/CBCT registrations. Additionally, target expansion margins were investigated for generating registration regions of interest. Test 1-Incremental sign correlation (ISC), gradient correlation (GC), gradient difference (GD), and normalized cross correlation (NCC) showed the smallest errors (mu +/- sigma: 1.6 +/- 0.9 approximately 2.9 +/- 2.1 mm). Test 2-Two of the three reviewers ranked GC higher. Test 3-Using GC, 96% of registrations showed &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;3-mm error when calcifications were filtered. Errors were left/right: 0.1 +/- 0.5mm, anterior/posterior: 0.8 +/- 1.0mm, and superior/inferior: 0.5 +/- 1.1 mm. The existence of calcifications increased the success rate to 97%. Expansion margins of 4-10 mm were equally successful. Gradient-based SMs were most accurate. Estimated error was found to be &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;3 mm (1.1 mm SD) in 96% of the registrations. Results suggest that the contour expansion margin should be no less than 4 mm.
The primary study objective was to determine the safety of intraprostatic administration of a rep... more The primary study objective was to determine the safety of intraprostatic administration of a replication-competent, oncolytic adenovirus containing a cytosine deaminase (CD)/herpes simplex virus thymidine kinase (HSV-1 TK) fusion gene concomitant with increasing durations of 5-fluorocytosine and valganciclovir prodrug therapy and conventional-dose three-dimensional conformal radiation therapy (3D-CRT) in patients with newly diagnosed, intermediate-to high-risk prostate cancer. Secondary objectives were to determine the persistence of therapeutic transgene expression in the prostate and to examine early posttreatment response. Fifteen patients in five cohorts received a single intraprostatic injection of 10 12 viral particles of the replication-competent Ad5-CD/TKrep adenovirus on day 1. Two days later, patients were administered 5-fluorocytosine and valganciclovir prodrug therapy for 1 (cohorts 1-3), 2 (cohort 4), or 3 (cohort 5) weeks along with 70 -74 Gy 3D-CRT. Sextant needle biopsy of the prostate was obtained at 2 (cohort 1), 3 (cohort 2), and 4 (cohort 3) weeks for determination of the persistence of transgene expression. There were no dose-limiting toxicities and no significant treatment-related adverse events. Ninety-four percent of the adverse events observed were mild to moderate and self-limiting. Acute urinary and gastrointestinal toxicities were similar to those expected for conventional-dose 3D-CRT. Therapeutic transgene expression was found to persist in the prostate for up to 3 weeks after the adenovirus injection. As expected for patients receiving definitive radiation therapy, all patients experienced significant declines in prostate-specific antigen (PSA). The mean PSA half-life in patients administered more than 1 week of prodrug therapy was significantly shorter than that of patients receiving prodrugs for only 1 week (0.6 versus 2.0 months; P < 0.02) and markedly shorter than that reported previously for patients treated with conventional-dose 3D-CRT alone (2.4 months). With a median follow-up of only 9 months, 5 of 10 (50%) patients not treated with androgen-deprivation therapy achieved a serum PSA < 0.5 ng/ml. The results demonstrate that replication-competent adenovirus-mediated double-suicide gene therapy can be combined safely with conventionaldose 3D-CRT in patients with intermediate-to high-risk prostate cancer. The shorter than expected PSA half-life in patients receiving more than 1 week of prodrug therapy may suggest a possible interaction between the oncolytic adenovirus and/or double-suicide gene therapies and radiation therapy.
Biochemical and Biophysical Research Communications, 1989
Chromatography of a DNA polymerase preparation from mitochondria of Saccharomyces cerevisiae on D... more Chromatography of a DNA polymerase preparation from mitochondria of Saccharomyces cerevisiae on DNA-cellulose column, using Tris-HCl (pH 7.5) buffer containing 0.6 M NaCl as eluent, was found to yield a fraction exhibiting DNA primase-like activity free of DNA polymerase. This fraction could support the synthesis of 12-15 residue-long oligoribonucleotides on single-stranded natural or synthetic DNA templates. The oligoribonucleotides could be further elongated by incorporation of deoxyribonucleotides in the presence of Klenow fragment.
Biochemical and Biophysical Research Communications, 1983
The effect of desaspidin, ortho-desaspidin, flavaspidic acid, nor-flavaspidic acid and desaspidin... more The effect of desaspidin, ortho-desaspidin, flavaspidic acid, nor-flavaspidic acid and desaspidinol on respiration and oxidative phosphorylation in rat liver mitochondria was studied.
International Journal of Radiation Oncology Biology Physics, 2007
Purpose/Objective(s): Presently RT and AS is considered standard of care in HR PC. Recent trials ... more Purpose/Objective(s): Presently RT and AS is considered standard of care in HR PC. Recent trials with RT and AS show a .15-20% biochemical failure (BF) rate in HR PC. In RTOG 85-31 and 86-10, the local failure (LF), distant metastases (DM) and overall survival (OS) rates after RT and long term AS were 30%, 52% and 51% respectively. The Dutch DHT study showed improved local control (LC) and OS with DHT and RT in other pelvic tumors like cervical cancer. A previous Duke University study enrolled 18 patients with HR PC treated with DHT and RT without AS, and their 3-yr LC, DM-free survival and disease-free survival (DFS) rates were 93%, 68%, and 25% respectively. Patients with HR PC were enrolled in this FDA and IRB approved phase I/II protocol to study the feasibility, tolerance and efficacy of DHT with RT and AS. Materials/Methods: Between 1999 and 2002, 23 patients (median age 61 yrs) with HR PC were enrolled in this Northwestern University phase I/II study. HR PC patients had one or more of the following factors: PSA .20 (10 pts), Gleason's score .7 (20 pts), T3/T4 tumors (16 pts) or pelvic node metastases (4 pts). All patients received AS with RT and adjuvant AS for 1-2 years. The median RT dose was 70.2 Gy to the prostate and 45 Gy to the pelvic nodes. External DHT was delivered weekly or twice weekly 72 hrs apart during RT using a BSD-2000 Sigma-60 applicator. Vital signs were monitored every five minutes according to protocol. The median number of DHT treatments was 10 (2-10). The aim was to achieve and maintain a minimum temperature of 42 C in a rectally placed temperature probe for 45-60 minutes. DHT tolerance was graded per protocol, acute and late toxicity was graded per CTCAE version 3.0. Results: The frequency of heating was 72 MHz with an applied power in the range of 400 to 900 watts. Cumulative average thermal dose (TD at 42.5 C) of 84.1 (± 63.7) minutes was achieved in an average of 9.2 (± 2.1) number of treatments. Average maximum temperature was 41.9 C (± 0.8). DHT was generally well tolerated with no new systemic or cardiac symptoms during or after DHT. The majority of patients (83%) received 10 DHT treatments. 1 patient refused further DHT after 2 sessions and 1 patient received 4 DHT treatments due to poor tolerance. 2 patients (9%) developed acute grade 2 dermatitis during DHT and RT. There were no acute or late grade 3-4 skin toxicity; however, 2 patients developed transient fat necrosis. 1 patient developed late grade 3 GU toxicity (cystitis). 3 patients (14%) developed late grade 3 rectal complications (bleeding) that were controlled with 1-2 sessions of laser therapy. No patient developed any late grade 4 GU or rectal toxicity. The median follow-up was 61.5 months (range 6-79). The 5 year OS, biochemical DFS, LC, and DM free-survival rates were 75%, 69%, 94% and 80%, respectively. Conclusions: This is the first report to describe the tolerance and efficacy of DHT, RT and AS in HR PC. This report demonstrates that this treatment regimen was well tolerated with minimal acute and late-toxicity. The OS and DFS rates of 70-75% are encouraging. LC rates of 94% in this group of patients with HR PC points to a potential synergy between DHT, RT, and AS. The predominant pattern of failure was distant metastases (20%). Future studies incorporating chemotherapy in addition to DHT, RT, and AS in HR PC are planned.
International Journal of Radiation Oncology Biology Physics, 2007
Purpose/Objective(s): CBCT registration to a reference image is one of the emerging tools used fo... more Purpose/Objective(s): CBCT registration to a reference image is one of the emerging tools used for prostate localization. This preliminary study compares fiducial marker co-registration to two methods of CBCT image registration utilizing Varian On-Board Imaging System TM (OBI) and in-house automatic fusion software. Materials/Methods: Seventy CBCT scans from two localized prostate cancer patients were used for this study. Both patients were implanted with three 1.2x3 mm soft tissue markers. Each patient was educated regarding a bowel regimen to facilitate an empty rectum prior to simulation and daily treatment. For daily treatments, patients were initially aligned to skin marks. On-line automatic image fusion between CBCT and simulation CT (Sim-CT) was performed using OBI version 1.3. Offsets were recorded in three translational degrees of freedom. Prior to treatment, fiducial marker co-registration was performed using two KV-orthogonal images and offsets were recorded and applied to treatment couch, defining the treatment position. Inter-fiducial distances (n= 450) were measured and recorded to check for seed migration. In an offline manner, automatic in-house registration, utilizing the uphill simplex, gradient correlation and mutual information similarity measures, was performed between Sim-CT and CBCT using the prostate as the region of interest. Fiducial marker data, considered the control, was compared to the two CBCT image registration methods. Mismatch between fiducial marker and OBI (Fd-OBI) and mismatch between fiducial marker and in-house fusion (Fd-house) was measured. Mismatch in the LR, AP, CC directions was reported and percentage of observations falling between 1 and 7 mm between the two registration methods was tabulated. Results: Inter-fiducial distances showed minimal seed migration with mean of <1±0.7 mm. Comparing the two methods of registration, Fd-house showed a mean mismatch of 1.0± 0.65, 1.0±0.96 and 1±1.07 mm in the LR, AP, and CC directions respectively. Comparable data was observed for the Fd-OBI data with mean of 1.0±0.74, 2.0±1.28, and 2.0±1.69 mm in the LR, AP, and CC directions respectively. Examining the percentage of mismatch observations (n= 414) the following data was observed: Conclusions: While the technical aspects of fiducial marker co-registration are attractive, invasiveness and seed migration can be noted as potential drawbacks. The phenomenon of seed migration was not observed in our study justifying the use of fiducial marker as a good control. Our in house automatic fusion software in conjunction with CBCT images showed a superior correlation to the fiducial markers and can offer an attractive noninvasive tool for improving prostate localization.
[bold Purpose:] To assess the accuracy and dosimetric implications of multi‐modality, online imag... more [bold Purpose:] To assess the accuracy and dosimetric implications of multi‐modality, online image‐guided localization methods, including intra‐modality 3D prostate ultrasound, cone beam CT (CBCT), implanted prostate markers and Calypso 4D localization for patients ...
International Journal of Radiation Oncology Biology Physics, 2010
To evaluate different similarity metrics (SM) using natural calcifications and observation-based ... more To evaluate different similarity metrics (SM) using natural calcifications and observation-based measures to determine the most accurate prostate and seminal vesicle localization on daily cone-beam CT (CBCT) images. CBCT images of 29 patients were retrospectively analyzed; 14 patients with prostate calcifications (calcification data set) and 15 patients without calcifications (no-calcification data set). Three groups of test registrations were performed. Test 1: 70 CT/CBCT pairs from calcification dataset were registered using 17 SMs (6,580 registrations) and compared using the calcification mismatch error as an endpoint. Test 2: Using the four best SMs from Test 1, 75 CT/CBCT pairs in the no-calcification data set were registered (300 registrations). Accuracy of contour overlays was ranked visually. Test 3: For the best SM from Tests 1 and 2, accuracy was estimated using 356 CT/CBCT registrations. Additionally, target expansion margins were investigated for generating registration regions of interest. Test 1-Incremental sign correlation (ISC), gradient correlation (GC), gradient difference (GD), and normalized cross correlation (NCC) showed the smallest errors (mu +/- sigma: 1.6 +/- 0.9 approximately 2.9 +/- 2.1 mm). Test 2-Two of the three reviewers ranked GC higher. Test 3-Using GC, 96% of registrations showed &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;3-mm error when calcifications were filtered. Errors were left/right: 0.1 +/- 0.5mm, anterior/posterior: 0.8 +/- 1.0mm, and superior/inferior: 0.5 +/- 1.1 mm. The existence of calcifications increased the success rate to 97%. Expansion margins of 4-10 mm were equally successful. Gradient-based SMs were most accurate. Estimated error was found to be &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;3 mm (1.1 mm SD) in 96% of the registrations. Results suggest that the contour expansion margin should be no less than 4 mm.
The primary study objective was to determine the safety of intraprostatic administration of a rep... more The primary study objective was to determine the safety of intraprostatic administration of a replication-competent, oncolytic adenovirus containing a cytosine deaminase (CD)/herpes simplex virus thymidine kinase (HSV-1 TK) fusion gene concomitant with increasing durations of 5-fluorocytosine and valganciclovir prodrug therapy and conventional-dose three-dimensional conformal radiation therapy (3D-CRT) in patients with newly diagnosed, intermediate-to high-risk prostate cancer. Secondary objectives were to determine the persistence of therapeutic transgene expression in the prostate and to examine early posttreatment response. Fifteen patients in five cohorts received a single intraprostatic injection of 10 12 viral particles of the replication-competent Ad5-CD/TKrep adenovirus on day 1. Two days later, patients were administered 5-fluorocytosine and valganciclovir prodrug therapy for 1 (cohorts 1-3), 2 (cohort 4), or 3 (cohort 5) weeks along with 70 -74 Gy 3D-CRT. Sextant needle biopsy of the prostate was obtained at 2 (cohort 1), 3 (cohort 2), and 4 (cohort 3) weeks for determination of the persistence of transgene expression. There were no dose-limiting toxicities and no significant treatment-related adverse events. Ninety-four percent of the adverse events observed were mild to moderate and self-limiting. Acute urinary and gastrointestinal toxicities were similar to those expected for conventional-dose 3D-CRT. Therapeutic transgene expression was found to persist in the prostate for up to 3 weeks after the adenovirus injection. As expected for patients receiving definitive radiation therapy, all patients experienced significant declines in prostate-specific antigen (PSA). The mean PSA half-life in patients administered more than 1 week of prodrug therapy was significantly shorter than that of patients receiving prodrugs for only 1 week (0.6 versus 2.0 months; P < 0.02) and markedly shorter than that reported previously for patients treated with conventional-dose 3D-CRT alone (2.4 months). With a median follow-up of only 9 months, 5 of 10 (50%) patients not treated with androgen-deprivation therapy achieved a serum PSA < 0.5 ng/ml. The results demonstrate that replication-competent adenovirus-mediated double-suicide gene therapy can be combined safely with conventionaldose 3D-CRT in patients with intermediate-to high-risk prostate cancer. The shorter than expected PSA half-life in patients receiving more than 1 week of prodrug therapy may suggest a possible interaction between the oncolytic adenovirus and/or double-suicide gene therapies and radiation therapy.
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