David S. Finley

The Temperature Scale and Mass Distribution of Hot DA White Dwarfs

Results are presented from a comprehensive spectroscopic survey of DA white dwarfs hotter than ~25,000 K. The observations consisted of CCD spectra with signal-to-noise ratios of ~100 in the blue, with ~5 A resolution. The majority of the spectra covered the wavelength range of 3500-7500 A, allowing the detection of a number of cool companions. To date, spectra have been obtained and analyzed for 174 DA stars. The spectra were analyzed using our model atmospheres, which are described in detail here, resulting in temperatures and gravities with average internal errors of 1% and 0.04 dex, respectively. Comparisons with previously published results showed that temperature determinations for Teff 1.1 M☉. The ultramassive DAs comprise a much larger fraction of the total than was the case for cooler samples. Calculations based on white dwarf evolutionary models showed that a higher proportion of massive white dwarfs is expected to be found in samples with Teff 30,000 K as a result of differential cooling effects. Within the range Teff > 40,000 K, the EUV-selected subsample did have proportionately more massive stars than the optically selected subsample. However, a detailed comparison showed that EUV and optical surveys were equally capable of detecting relatively nearby massive white dwarfs. On the other hand, interstellar EUV absorption eliminated from the EUV sample many of the more distant stars that were detectable optically. Therefore, the apparent excess of massive DA white dwarfs in the EUV sample is largely due to a relative deficit of stars with more typical masses. Results are presented for individual stars, including a number of subdwarf identifications and reports of detections of cool companions. Properties of some of the more interesting binaries are discussed. We also report on some stars in the sample that evidently have varying He abundances. WD 0612+177 (G104-27) had been observed, at one point, to have photospheric He I; we confirm that He has remained absent since then. WD 0718-316 (RE 0720-314) is in a post-common-envelope binary and has photospheric He II, the abundance of which appears to vary by more than an order of magnitude over timescales of months.

Robotic versus standard laparoscopic partial/wedge nephrectomy: a comparison of intraoperative and perioperative results from a single institution.

PURPOSE Laparoscopic partial/wedge nephrectomy, similar to laparoscopic radical prostatectomy, is a technically challenging procedure that is performed by a limited number of expert laparoscopic surgeons. The incorporation of a robotic surgical interface has dramatically increased the use of minimally invasive pelvic surgery such that robotic laparoscopic radical prostatectomy is commonly performed even by laparoscopically naïve surgeons. This analysis compares the outcomes of our initial experience with robot-assisted laparoscopic partial nephrectomy (RLPN) performed by an experienced open surgeon to that of standard laparoscopic partial nephrectomy (LPN) performed by two experienced laparoscopic surgeons. PATIENTS AND METHODS We reviewed the medical records of 11 consecutive patients who underwent 12 standard LPNs (EMM, RVC) (one patient had two unilateral tumors) and 10 consecutive patients (representing the first 11 of such robotic procedures performed at our institution) who underwent 11 RLPNs (one patient had bilateral tumors managed in an asynchronous manner) (DKO). RESULTS The mean tumor size was 2.3 cm (range 1.7-6.2 cm) for LPN and 3.1 cm (range 2.5-4 cm) for RLPN. The mean total procedure time was 289.5 minutes (range 145-369 min) for LPN and 228.7 minutes (range 98-375 min) for RLPN (P=0.102). The mean estimated blood loss was 198 mL (range 75-500 mL) for LPN v 115 mL (25-300 mL) for RLPN (P=0.169). The mean warm ischemia time was 35.3 minutes (range 15-49 min) in the LPN group and 32.1 minutes (range 30-45 minutes) in the RLPN group (P=0.501). CONCLUSIONS Introducing a robotic interface for laparoscopic partial/wedge resection allowed a fellowship-trained urologic oncologist with limited reconstructive laparoscopic experience to achieve results comparable to those for laparoscopic partial/wedge resection performed by experienced laparoscopic surgeons. In this regard, the learning curve appears truncated, similar to that with robot-assisted laparoscopic prostatectomy.

Percutaneous and Laparoscopic Cryoablation of Small Renal Masses

PURPOSE We reviewed our 4-year experience with percutaneous cryoablation and laparoscopy for treating small renal masses. MATERIALS AND METHODS After institutional review board approval we retrospectively analyzed renal cryoablation procedures performed between March 2003 and October 2007. An in-depth analysis was performed concerning demographics, hospital course and short-term outcome with respect to percutaneous vs laparoscopic cryoablation. RESULTS A total of 37 patients underwent treatment for 43 renal masses. Of the 37 patients 19 underwent laparoscopic cryoablation (24 tumors) and 18 underwent percutaneous cryoablation (19 tumors) using computerized tomography fluoroscopy. For percutaneous cryoablation a saline instillation was used in 58% of cases to move nonrenal vital structures away from the targeted renal mass. There were 5 cases of hemorrhage requiring transfusion, all of which were associated with the use of multiple cryoprobes. The transfusion rate in the percutaneous and laparoscopic cryoablation groups was 11.1% and 27.8%, respectively. Operative time was significantly longer in the laparoscopic cryoablation group compared to the percutaneous cryoablation group at 147 (range 89 to 209) vs 250.2 (range 151 to 360) minutes, respectively. The overall complication rate (including transfusion) was lower in the percutaneous cryoablation group compared to the laparoscopic cryoablation group (4 of 18 [22.2%] vs 8 of 20 [40%], respectively). Hospital stay was significantly shorter in the percutaneous vs laparoscopic cryoablation group at 1.3 vs 3.1 days, p <0.0001, respectively. Narcotic use in the percutaneous cryoablation group was more than half that used by the laparoscopic cryoablation group (5.1 vs 17.8 mg, p = 0.03, respectively). Among patients with biopsy proven renal cell carcinoma during a median followup of 11.4 and 13.4 months in the percutaneous and laparoscopic cryoablation groups, cancer specific survival was 100% and 100%, respectively, and the treatment failure rate was 5.3% and 4.2%, respectively. CONCLUSIONS Percutaneous cryoablation is an efficient, minimally morbid method for the treatment of small renal masses and it appears to be superior to the laparoscopic approach. Short-term followup has shown no difference in tumor recurrence or need for re-treatment. Of note, hemorrhage was solely associated with the use of multiple probes.

Tumor Biology and Prognostic Factors in Renal Cell Carcinoma

In the past 15 years, there has been an increased understanding of the tumor biology of renal cell carcinoma (RCC). The identification of vascular endothelial growth factor (VEGF), its related receptor (VEGFR), and the mammalian target of rapamycin as dysregulated signaling pathways in the development and progression of RCC has resulted in the rational development of pharmaceutical agents capable of specifically targeting key steps in these pathways. Clinical trials have demonstrated survival benefit with these agents, particularly in clear cell RCC patients. However, metastatic RCC will progress in all patients, resulting in a critical need to determine patient risk and optimize treatment. The goal of this article is to highlight the significant breakthroughs made in understanding the critical genetic alterations and signaling pathways underlying the pathogenesis of RCC. The discovery of prognostic factors and development of comprehensive nomograms to stratify patient risk and predictive biomarkers to facilitate individualized treatment selection and predict patient response to therapy also are reviewed.

Periprostatic Adipose Tissue as a Modulator of Prostate Cancer Aggressiveness

PURPOSE Adipose tissue has been suggested to contribute to the pathogenesis of various disease states, including prostate cancer. We investigated the association of cytokines and growth factors secreted by periprostatic adipose tissue with pathological features of aggressive prostate cancer. MATERIALS AND METHODS Periprostatic adipose tissue was harvested from patients undergoing radical prostatectomy and cultured for 24 hours to generate conditioned medium or snap frozen immediately for functional signaling profiling. Multiplex analysis of the periprostatic adipose tissue conditioned medium was used to detect cytokine levels and compared to patient matched serum from 7 patients. Interleukin-6 in serum and periprostatic adipose tissue conditioned medium was further analyzed by enzyme-linked immunosorbent assay and correlated with clinical variables, such as age, body mass index and Gleason score, in 45 patients. Interleukin-6 expression in periprostatic adipose tissue was determined by immunohistochemistry. Reverse phase protein microarray technology was used to analyze cell signaling networks in periprostatic adipose tissue. RESULTS Interleukin-6 in periprostatic adipose tissue conditioned medium was approximately 375 times greater than that in patient matched serum and levels correlated with pathological grade. This finding was further extended by cell signaling analysis of periprostatic adipose tissue, which showed greater phosphorylation on Stat3 with high grade tumors (any component of Gleason score 4 or 5). CONCLUSIONS Higher Gleason score correlated with high levels of conditioned medium derived interleukin-6. Moreover, cell signaling analysis of periprostatic adipose tissue identified activated signaling molecules, including STAT3, that correlated with Gleason score. Since STAT3 is interleukin-6 regulated, these findings suggest that periprostatic adipose tissue may have a role in modulating prostate cancer aggressiveness by serving as a source of interleukin-6. Also, we found low numbers of inflammatory cells in the fat, suggesting that adipocytes are the major secretors of interleukin-6.

Continence Definition After Radical Prostatectomy Using Urinary Quality of Life: Evaluation of Patient Reported Validated Questionnaires

PURPOSE After radical prostatectomy continence is commonly defined as no pads except a security pad or 0 to 1 pad. We evaluated the association of pad status and urinary quality of life to determine whether security and 1 pad status differ from pad-free status to better define 0 pads as the post-prostatectomy standard. MATERIALS AND METHODS A total of 500 consecutive men underwent robot assisted radical prostatectomy from October 2003 to July 2007. Data were collected prospectively and entered into an electronic database. Postoperatively men completed self-administered validated questionnaires including questions on 1) daily pad use (0, security, 1, or 2 or more), 2) urine leakage (daily, about once weekly, less than once weekly or not at all), 3) urinary control (none, frequent dribbling, occasional dribbling or total control), 4) American Urological Association symptom score and 5) urinary quality of life. RESULTS Postoperatively men who indicated 0 pad use had a mean +/- SE symptom score of 5.8 +/- 0.3 and pleased quality of life (1.16 +/- 0.08). In contrast, men with a security pad and 1 pad had a symptom score of 7.6 +/- 0.7 and 9.2 +/- 0.6 but mixed quality of life (2.78 +/- 0.18 and 3.41 +/- 0.15, respectively, p <0.0005). CONCLUSIONS Results show a significant decrease in quality of life between no pads (1.16 or pleased), a security pad and 0 or 1 pad (2.78 and 3.41 or mixed, respectively). Findings do not support defining continence with a security pad or 0 to 1 pad. Continence should be strictly defined as 0 pads.

Optical Spectroscopy of Supernova 1993J During Its First 2500 Days

We present 42 low-resolution spectra of supernova (SN) 1993J, our complete collection from the Lick and Keck observatories, from day 3 after explosion to day 2454, as well as one Keck high-dispersion spectrum from day 383. SN 1993J began as an apparent SN II, albeit an unusual one. After a few weeks, a dramatic transition took place, as prominent helium lines emerged in the spectrum. SN 1993J had metamorphosed from a SN II to a SN IIb. Nebular spectra of SN 1993J closely resemble those of SNe Ib and Ic, but with a persistent Hα line. At very late times, the Hα emission line dominated the spectrum, but with an unusual, boxlike profile. This is interpreted as an indication of circumstellar interaction.

Hepatic artery pseudoaneurysm : A report of seven cases and a review of the literature

PurposeTo analyze seven cases of hepatic artery pseudoaneurysm (HAP) encountered at our hospital and review the relevant literature.MethodsWe searched the computerized medical record database from January 1, 1996, to September 1, 2003, to identify all cases of HAP, which we then reviewed in detail, examining etiology, findings, laboratory data, therapeutic intervention, complications, and outcome. We then compared these findings with those reported in the literature.ResultsThere were five cases of HAP among 18 015 trauma and surgical admissions to the University of California Irvine Medical Center, representing an incidence of 0.03%. There were an additional two cases of HAP among 200 orthotopic liver transplants (OLT). The five HAPs not associated with OLT were preceded by blunt abdominal trauma, liver biopsy, pancreatic pseudocyst, and polyarteritis nodosa, in one patient each, and there was no apparent cause in one patient. Two patients were treated by ligation, and the patients with post-OLT HAP underwent resection and replacement with saphenous bypass grafts. Successful embolization was performed in the other three patients.ConclusionHepatic artery pseudoaneurysm is a rare but dangerous complication of both acute surgical and chronic injury to the hepatic artery. However, early diagnosis and intervention can result in an excellent long-term outcome.

Performance and Preliminary Calibration of the Hopkins Ultraviolet Telescope on the Astro-2 Mission

An improved version of the Hopkins Ultraviolet Telescope (HUT) made its second flight on the Astro-2 mission aboard the Space Shuttle Endeavour from 1995 March 2-18. The longer mission duration and greatly improved pointing stability relative to Astro-1 made possible 385 observations of 265 celestial targets at far-ultraviolet wavelengths. Observing efficiency exceeding 60% over 14 days of science operations yielded 205 hr of on-source integration time, a factor of 5.1 increase over Astro-1. We describe changes to the instrument following Astro-1 and the in-flight photometric calibration, which is based on a comparison of our observations of the hot DA white dwarf HZ 43 with a model atmosphere whose parameters were derived from optical observations. The peak effective area is 24.1 cm2 at 1160 A, where the inverse sensitivity is 7.09 × 10-13 ergs cm-2 count-1. This is an improvement by a factor of 2.3 over Astro-1, largely attributable the installation of new optics coated with ion-sputtered silicon carbide. Observations of several other white dwarfs indicate that the calibration is accurate to about 5%, after correction for modest, but significant, time-dependent degradation during the mission. The spectral resolution varied from 2 to 4 A over the first-order wavelength range of 820-1840 A. The wavelength scale is established to better than 1 A. As on Astro-1, dark counts and scattered light were extremely low. Airglow line intensities were much lower because of the lower level of solar activity. When all factors are considered together, HUT performance on Astro-2 was a full order of magnitude better than that achieved on the highly successful Astro-1 mission.

Purification and direct transformation of epithelial progenitor cells from primary human prostate

Epithelial cell transformation has been demonstrated in numerous animal models for the study of solid tumor biology. However, little evidence exists for human epithelial cell transformation without previous immortalization via genetic influences such as SV40 T-antigen, thus limiting our knowledge of the events that can transform naive human epithelium. Here we describe a system developed in our laboratory to directly transform freshly isolated primary human prostate epithelial cells without previous culture or immortalization. Prostate tissue is obtained from patients and benign tissue is separated from malignant tissue. Benign and malignant tissues are mechanically and enzymatically dissociated to single cells overnight, and immune cells and epithelial subsets are isolated on the basis of differential expression of surface antigens. Epithelial progenitor cells are transduced with lentiviruses expressing oncogenes and combined with inductive stroma for in vivo studies. At 8–16 weeks after transplantation into immune-deficient mice, the development of lesions, histologically classified as benign prostate, prostatic intraepithelial neoplasia and adenocarcinoma, can be evaluated.