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D S Smith

Publications and source records attributed to D S Smith.

At least 55 records · Page 3Linked to original sources
PubMed1998

Preemptive epidural analgesia and recovery from radical prostatectomy: a randomized controlled trial.

CONTEXT: Preemptive analgesia can decrease the sensitization of the central nervous system that would ordinarily amplify subsequent nociceptive input, but a clear demonstration of its clinical efficacy is necessary for it to become a routine component of acute pain therapy. OBJECTIVE: To determine the impact of preemptive epidural analgesia on postoperative pain and other clinically important outcome variables after radical retropubic prostatectomy. DESIGN AND SETTING: A block randomized double-blind clinical trial lasting 20 months at a single academic medical center. PATIENTS: A total of 100 generally healthy and neurologically intact patients scheduled for radical retropubic prostatectomy for the treatment of prostate cancer in whom an epidural catheter for treating postoperative pain was to be placed prior to the induction of general anesthesia. INTERVENTIONS: Epidural bupivacaine, epidural fentanyl, or no epidural drug was administered prior to induction of anesthesia and throughout the entire operation, followed by aggressive postoperative epidural analgesia for all patients. MAIN OUTCOME MEASURES: Daily pain scores during hospitalization and pain scores obtained 3.5, 5.5, and 9.5 weeks after hospital discharge. RESULTS: The patients who received epidural fentanyl or bupivacaine prior to surgical incision (preemptive analgesia) experienced 33% less pain while hospitalized (P=.007). Pain scores in those receiving preemptive analgesia were significantly lower at 9.5 weeks (P=.02), but were not significantly different at 3.5 or 5.5 weeks. At 9.5 weeks, 32 (86%) of 37 patients receiving preemptive analgesia were pain-free compared with 9 (47%) of 19 control patients (P=.004). Patients receiving preemptive analgesia were more active 3.5 weeks after surgery (P=.01), but not at 5.5 or 9.5 weeks. CONCLUSIONS: Even in the presence of aggressive postoperative pain management, preemptive epidural analgesia significantly decreases postoperative pain during hospitalization and long after discharge, and is associated with increased activity levels after discharge.

Aged↗
PubMed1998

On-road assessment of driving competence after brain impairment: review of current practice and recommendations for a standardized examination.

OBJECTIVE: To examine the approaches to on-road assessment of driver competence in persons with brain impairment. Items examined were procedures, standardization, scoring methods, equipment requirements, and determination of fitness to drive. DATA SOURCES: All studies identified through citation or Medline search. STUDY SELECTION: The studies reviewed were those published from 1971 to the present that examined driving competence after brain impairment, as measured by a driving test. DATA EXTRACTION: A qualitative review of published studies reporting methodologies and authors' conclusions abstracted from sourced publications. DATA SYNTHESIS: Off-road driving assessments examine proficiency in operating a motor vehicle, but not ability to drive in traffic or accurate prediction of safe driving. On-road driving assessments have been used to examine the predictive validity of other driving assessment methods or the driving performance of subjects with brain impairment. Determining a subject's competence to drive is frequently a subjective evaluation. With a standardized driving test, a significant correlation between the objective driving score and the rater's global evaluation of fitness has been reported. CONCLUSION: Closed-course, off-road driving tests are recommended for examining vehicle operation skills and readiness for in-traffic evaluation only. This allows practice with any vehicle adaptations before on-road evaluation and identification of clients who are unsafe to proceed on-road. A practical driving test in traffic, with standardized route and driving maneuvers, is recommended for determining driver competence. Scoring of driving performance should be standardized, reliable, and specific, to identify deficient driving skills that may be amenable to training. Driving performance should be evaluated according to predefined criteria, and the judgment regarding competence should be closely related to this objective measure.

Automobile Driver Examination↗
PubMed1998

Adult endopyelotomy: impact of etiology and antegrade versus retrograde approach on outcome.

PURPOSE: We evaluate our experience with endopyelotomy for ureteropelvic junction obstruction by stratifying the results of an antegrade versus a retrograde approach for primary, secondary, calculi related, high insertion and impaired renal function related obstruction, individually. MATERIALS AND METHODS: We retrospectively reviewed results of 149 nonrandomized patients treated for ureteropelvic junction obstruction, of whom 83 underwent antegrade percutaneous endopyelotomy using a right angle Greenwald electrode and 66 underwent retrograde endopyelotomy using a cutting balloon device. Subjective results were based on an analog pain scale, objective results on renal scan, excretory urography or Whitaker test and cost-effectiveness analysis on total treatment cost. RESULTS: In both primary and secondary ureteropelvic junction obstruction, retrograde endopyelotomy was related to a significantly shorter operating room time and hospital stay (p < 0.05). When treating noncalculous primary ureteropelvic junction obstruction (92 patients) there was a better objective, albeit not statistically significant, success rate with antegrade endopyelotomy (89 versus 71%) but retrograde endopyelotomy was 20% more cost-effective. When treating secondary ureteropelvic junction obstruction (37 patients) there was a better objective, albeit not statistically significant, success rate (83 versus 77%) with retrograde endopyelotomy, which was 37% more cost-effective. Complication rates were higher with antegrade compared to retrograde endopyelotomy for primary and secondary ureteropelvic junction obstruction (25 versus 14% and 26 versus 0%). In 20 patients with concomitant stones endopyelotomy results were better (93 to 100% success) than for any other categories of ureteropelvic junction obstruction. Of note, endopyelotomy also provided a reasonable outcome among patients with a high insertion primary ureteropelvic junction obstruction (70% success). CONCLUSIONS: Antegrade endopyelotomy is the preferred approach in patients with primary ureteropelvic junction obstruction and concomitant renal calculi (13.4% of cases), and may also be preferable in patients with high insertion obstruction (6.7%). For all other primary and all secondary ureteropelvic junction obstruction, antegrade and retrograde endopyelotomy is effective therapy yet retrograde endopyelotomy results in less operating room time, shorter hospital stay, fewer complications and significantly less expense to achieve the desired outcome.

Adolescent↗
PubMed1998

Clinical and pathologic tumor characteristics of prostate cancer as a function of the number of biopsy cores: a retrospective study.

OBJECTIVES: Many men with negative prostate biopsies and persistently elevated serum total prostate-specific antigen (tPSA) values will have cancer detected on a repeated biopsy. An important issue is whether the cancer would have been detected on the initial biopsy had more biopsy samples been obtained. The objective of our study was to retrospectively characterize the clinical and pathologic tumor features associated with men who underwent sextant core biopsies compared with men who needed more than six core biopsies during one or more biopsy sessions to detect prostate cancer. Transrectal ultrasound (TRUS)-estimated prostatic volume was evaluated to determine whether the number of biopsy cores needed for prostate cancer detection was influenced by gland size. METHODS: We retrospectively evaluated the number of biopsy core samples obtained in 185 men (mean age 63+/-6 years) enrolled in our PSA-based screening study for prostate cancer who were found to have prostate cancer and elected radical prostatectomy as treatment. Correlation coefficients were calculated and univariate analyses were performed to evaluate clinical (age, tPSA, TRUS volume, PSA density) and pathologic (Gleason score, pathologic weight, organ confinement, "possibly harmless" cancer) characteristics associated with men who required more biopsy cores to detect the cancer. RESULTS: Of the 185 men, 103 (56%) had 6 or fewer total biopsy cores taken and 82 (44%) had more than 6 cores (44 [24%] of 185 had 7 to 12 cores and 38 [20%] of 185 had 13 or more cores). There was a positive correlation between age, serum tPSA, TRUS-determined prostate volume, and pathologic specimen weight and an increasing number of total cores (all P values < 0.05). The number of biopsy cores was not associated with PSA density, Gleason score, cancer volume, organ confinement, or "possibly harmless" cancers (all P values > 0.05). Men with a TRUS volume 30 cc or less (46%) required a mean of 8 total cores to detect the cancer compared with a mean of 11 cores (P = 0.003) in men with a TRUS volume greater than 30 cc (54%). A greater percentage of men with a TRUS prostate volume greater than 30 cc compared with men whose volume was 30 cc or less would have had their cancer missed with only a six-core biopsy (64% versus 46%, P = 0.01). CONCLUSIONS: Sextant core biopsies may be inadequate to detect prostate cancer in some men. These data support the performance of more than six core biopsies to detect clinical prostate cancer. A prospective trial using TRUS-determined prostate volume to determine the number of cores to take is needed to accurately assess this issue.

Adult↗
PubMed1998

Biochemical response to testicular androgen ablation among patients with prostate cancer for whom flutamide and/or finasteride therapy failed.

OBJECTIVES: To evaluate the response of testicular androgen ablation in patients with advanced prostate cancer with a biochemical recurrence after finasteride or combined finasteride and flutamide therapy. METHODS: Eighteen hormone naïve men with advanced prostate cancer (10 with detectable prostate-specific antigen [PSA] levels after radical prostatectomy, 4 with rising PSA levels after definitive radiation therapy, and 4 with Stage D2 disease) were treated with finasteride (5 mg/day) alone or in combination with flutamide (250 mg three times a day). All men experienced an initial reduction in serum PSA, but later had treatment failure with two consecutive rising PSA measurements. All men were then treated with testicular androgen ablation (bilateral orchiectomy in 15 and luteinizing hormone-releasing hormone analogue in 3). RESULTS: Overall, serum PSA declined by more than 80% in 15 (83%) of 18 and to undetectable levels in 14 (78%) of 18. With a median+/-semi-interquartile range follow-up of 22+/-14.5 months from the initiation of hormone therapy, 12 (67%) of 18 currently have undetectable PSA levels. Two men having rising serum PSA levels above 100 ng/mL and 1 man has died from complications of metastatic prostate cancer. CONCLUSIONS: Testicular androgen ablation effectively lowers serum PSA levels in most men with advanced prostate cancer who have experienced a biochemical recurrence despite initial response and subsequent relapse on finasteride or combined finasteride and flutamide therapy.

Aged↗
PubMed1998

Redistribution of imipramine from regions of the brain under the influence of circulating specific antibodies.

The kinetics of brain-to-blood redistribution of imipramine (IMI) was assessed in nine brain regions of control rats and rats given anti-tricyclic antidepressant (anti-TCA) antibody. Two antibodies were given intravenously 6 min after intravenous [3H]IMI (1 nmol/kg). One was a murine monoclonal IgG1 (Ka = 3.8 x 10(7) M(-1)) at an IgG/IMI molar ratio of 1,000 (IgG1,000), and the other was a sheep polyclonal IgG (TAb; Ka = 1.3 x 10(10) M(-1)) at IgG/IMI molar ratios of 1, 10, and 100 (TAb1, TAb10, and TAb100). In the control rats, IMI was rapidly taken up by the brain (Cmax at 5 min) with no significant differences among the brain regions (4.1 +/- 0.4 to 5.4 +/- 0.6 pmol/ g), and brain IMI then declined monoexponentially with a half-life of 44.2 min (cerebellum) to 77.3 min (hippocampus). The greatest IMI content was in the frontal cortex and the lowest in the cerebellum. The antibodies (except TAb1) stimulated the extent and rate of IMI redistribution from all the brain regions depending on the immunoreactive capacity (NKa) of the antibody. The antibody with the highest NKa (TAb100) had the greatest effect. The fraction of IMI removed from the brain was 58-74%, and the redistribution half-life was 7.9-15.6 min; the mean residence time was reduced by 66-75% (11.8-23.9 min). These results demonstrate that circulating anti-TCA IgG rapidly and reliably removes IMI from the brain, indicating that immunotoxicotherapy could be an efficient procedure for accelerating the removal of TCA from the brain.

Animals↗
PubMed1998

Seroconversion of type B to O erythrocytes using recombinant Glycine max alpha-D-galactosidase.

Recombinant alpha-D-galactosidase (rGal) from soybean (Glycine max) hydrolyzed the immunodominant alpha-D-galactose residue from the B epitope of red blood cells. This converted type B erythrocytes to type O which are "universally" transfusable. Type B red blood cells were obtained from four different donors and enzymatically converted. Cell function parameters, including red cell indices, pH, methemoglobin, carboxyhemoglobin, osmotic fragility, hemolysis, 2,3-diphosphoglycerate, cholinesterase, ATP, and antigen typing of treated cells were compared to controls. These pilot studies indicate that rGal could have potential biotechnical application in the production of universally transfusable red blood cells.

2,3-Diphosphoglycerate↗
PubMed1998

Factors contributing to patient satisfaction with rehabilitation following stroke.

This study charted changes in patient satisfaction with their rehabilitative progress over time, and examined the relative contributions of several factors to satisfaction. Participants were assessed on admission to and discharge from rehabilitation, and six and 12 months after discharge. The study was undertaken in the rehabilitation unit at Repatriation General Hospital, in Adelaide, South Australia. Participants were 60 12-month stroke survivors who had undergone an inpatient rehabilitation programme. Satisfaction with progress in five areas of function was assessed using a five point rating scale. Functional outcome was assessed with the Australian ADL Index (competence and performance), lifestyle activities with the Frenchay Activities Index, knowledge of stroke with the Stroke Care Information Test, depression with the Zung Self-Rating Depression Scale, family functioning with the McMaster Family Assessment Device, and patients' expectations of rehabilitation by a qualitative assessment. Satisfaction with progress improved with time, particularly for dressing and washing, but for mobility declined after discharge. Satisfaction with progress was consistently influenced by the return to previous lifestyle activities, depression, family functioning, understanding of stroke, and clarity of expectations on admission to rehabilitation. It is important that the concept of successful rehabilitation acknowledges the perspective of the patient.

Activities of Daily Living↗
PubMed1998

Cancer recurrence and survival rates after anatomic radical retropubic prostatectomy for prostate cancer: intermediate-term results.

PURPOSE: We evaluate cancer recurrence and survival rates following anatomic radical retropubic prostatectomy. MATERIALS AND METHODS: From 1983 through August 1997, 1 surgeon performed anatomic radical retropubic prostatectomy in 1,778 men (mean age plus or minus standard deviation 63+/-7), using a unilateral or bilateral nerve sparing modification when feasible (93%). Postoperative adjuvant radiation therapy (mean dose 60 Gy.) was given to 4% of patients because of adverse pathological findings. Patients were followed with semiannual prostate specific antigen (PSA) tests and annual digital rectal examinations. Followup PSA 0.3 ng./ml. or greater was considered evidence of cancer recurrence. We used Kaplan-Meier product limit estimates to calculate 7-year cancer recurrence-free probabilities, prostate cancer specific survival and all cause survival (overall, and stratified by age, preoperative PSA, tumor grade and tumor stage). We used multivariate Cox proportional hazards models to determine clinical and pathological parameters that provided unique predictive information about cancer recurrence. RESULTS: The 7-year recurrence-free survival was significantly associated with lower preoperative PSA (estimated probability of nonprogression 76 to 93% for PSA less than 10), nonpalpable, localized clinical stage (79%), lower tumor grade (84 and 68% for well and moderately differentiated, respectively) and localized pathological stage (81% for pT1 or pT2) (all log rank test p <0.0001) but not age at surgery. All predictors except clinical stage and age remained significant within the multivariate model. Controlling for all other predictors, adjuvant radiation therapy in patients with unfavorable pathology was significantly associated with better recurrence-free survival (p=0.02). The estimated 7-year prostate cancer specific survival rate was 97% and the all cause survival rate was 90%. Cancer specific and all cause survival were significantly associated with lower grade and localized pathological stage (p <0.0001). CONCLUSIONS: Anatomic radical retropubic prostatectomy with the nerve sparing modification can be performed with good cancer control.

Adult↗
PubMed1998

Somatic origin of T-cell epitopes within antibody variable regions: significance to monoclonal therapy and genesis of systemic autoimmune disease.

During an immune response, specific antibody variable region genes are diversified by a somatic point mutation process that generates de novo "foreign" V-region sequences. This creates an interesting problem in immune regulation because B cells are highly proficient at self-presenting V-region peptides in the context of class II MHC. Though our studies indicate that the corresponding T-cell repertoire attains a state of tolerance to germline-encoded antibody V-region diversity, it is presently unknown whether the same is true of mutationally generated diversity. On the basis of immunoregulatory considerations, we hypothesize that contact exclusion or tolerance normally precludes T cells from helping B cells via self-presented mutant V-region peptides. The lack of recurrent somatic mutations that create known T-cell epitopes in antibody V regions lends some support to this idea. In contrast, our studies of spontaneously autoreactive B cells in systemic autoimmune disease strongly suggest that precursors of such cells are recruited by T-cell help directed to self-presented mutant idiopeptides. Failures in tolerance or contact exclusion mechanisms may be responsible for this apparently abnormal event. In addition to their importance in immune regulation, somatic mutations or other differences from germline-encoded V-region sequence may be largely responsible for undesirable patient responses to therapeutic monoclonal antibodies. These reactions might be averted or diminished by inducing tolerance in the T-cell repertoire with synthetic peptide correlates of non-germline-encoded V-region sequences in humanized antibodies.

Amino Acid Sequence↗
PubMed1998

The effects of depression and abnormal illness behaviour on outcome following rehabilitation from stroke.

OBJECTIVE: To examine the relative effects of depression and abnormal illness behaviour (AIB) on long-term rehabilitation outcome following stroke. DESIGN: A longitudinal design, with assessments on admission to and discharge from rehabilitation, and six and twelve months after discharge. SETTING: The study was undertaken in the rehabilitation unit at Repatriation General Hospital, in Adelaide, South Australia. SUBJECTS: Ninety-four twelve-month stroke survivors who had undergone an inpatient rehabilitation programme. MAIN OUTCOME MEASURES: AIB was assessed using the Illness Behaviour Questionnaire, and depression with the Zung Self-Rating Depression Scale. The General Health Questionnaire and a visual analogue mood scale were also used. Functional outcome was assessed with the competence and performance assessments of the Australian ADL Index, and lifestyle activities with the Frenchay Activities Index. RESULTS: Multivariate analysis of outcome controlled for age and stroke severity. AIB was a better predictor of functional competence and performance than either age or stroke severity, at rehabilitation discharge and both six and twelve months later. Depression was not related to functional competence and performance at any assessment, but was strongly predictive of an inactive lifestyle at both six and twelve months. By contrast, lifestyle activities were not related to AIB. CONCLUSIONS: Depression and AIB appear to have quite distinct effects on outcome. AIB emerged as a key determinant of long-term functional disability, while depression was associated with poorer social functioning. The early recognition and treatment of AIB and depression is important for the ultimate social and functional outcomes of stroke rehabilitation patients.

Activities of Daily Living↗
PubMed1998

Knowledge of stroke in rehabilitation and community samples.

This study examined the stroke knowledge of 60 stroke rehabilitation patients, 46 spouses, 25 family members, and 103 people in the general community. Changes in stroke knowledge with time, and determinants of stroke knowledge, were also examined. Clinical participants were assessed on acute admission, admission to and discharge from rehabilitation, and 6 and 12 months after discharge. Community participants were assessed once. Instruments used were the Stroke Care Information Test, Australian ADL Index, Frenchay Activities Index, Illness Behaviour Questionnaire and Zung Self-rating Depression Scale. The stroke knowledge of all participants, particularly patients, was poor, but improved with time. Better-informed patients were younger, had milder strokes, were less depressed, were less likely to develop abnormal illness behaviour, and made a better functional recovery than patients with poorer knowledge. Structured information programmes are needed for stroke patients and their families. Improved community awareness of stroke may help the prospects for recovery and quality of life for people who have strokes.

Aged↗
PubMed1998

Lower caliceal stone clearance after shock wave lithotripsy or ureteroscopy: the impact of lower pole radiographic anatomy.

PURPOSE: We determine whether there is a significant relationship between the spatial anatomy of the lower pole, as seen on preoperative excretory urography (IVP), and the outcome after shock wave lithotripsy or ureteroscopy for a solitary lower pole caliceal stone 15 mm. or less. MATERIALS AND METHODS: Between January 1992 and June 1996, 34 patients with 15 mm. or less solitary lower pole stone underwent ureteroscopy with intracorporeal lithotripsy (13) or extracorporeal shock wave lithotripsy (ESWL) with a Dornier HM3 lithotriptor (21). On pretreatment IVP lower pole infundibular length and width, infundibulopelvic angle of the stone bearing calix were measured. Stone size and area were determined from an abdominal plain x-ray. A plain x-ray of the kidneys, ureters and bladder was obtained in all patients at a median followup of 12.3 and 8 months in the ureteroscopy and ESWL groups, respectively. RESULTS: After initial therapy the overall stone-free rate was 62 and 52% in the ureteroscopy and ESWL groups, respectively. Stone-free status after ESWL was significantly related to each anatomical measurement. Infundibulopelvic angle 90 degrees or greater, and infundibular length less than 3 cm. and width greater than 5 mm. were each noted to correlate with an improved stone-free rate after ESWL. In contrast, the stone-free rate after ureteroscopy was not statistically significantly impacted by these anatomical features, although a clinical stone-free trend was identified relating to a favorable infundibular length and infundibulopelvic angle. The infundibulopelvic angle was 90 degrees or greater in 4 stone-free patients (12% overall), including 2 who underwent ureteroscopy and 2 who underwent ESWL. On the other hand, in 2 and 4 stone-free patients (18% overall) who underwent ureteroscopy and ESWL, respectively, favorable radiographic features consisted of a short, wide but acutely angulated infundibulum with the infundibulopelvic angle less than 90 degrees, and infundibular length less than 3 cm. and width 5 mm. or greater. In contrast, in 4 and 6 patients (29% overall) who underwent ureteroscopy and ESWL, respectively, all 3 radiographic features were unfavorable with the infundibulopelvic angle less than 90 degrees, and infundibular length greater than 3 cm. and width less than 5 mm. In these cases the stone-free rate was 50 and 17% after ureteroscopy and ESWL, respectively. CONCLUSIONS: The 3 major radiographic features of the lower pole calix (infundibulopelvic angle, and infundibular length and width) can be easily measured on standard IVP using a ruler and protractor. Each factor individually has a statistically significant influence on stone clearance after ESWL. A wide infundibulopelvic angle or short infundibular length and broad infundibular width regardless of infundibulopelvic angle are significant favorable factors for stone clearance following ESWL. Conversely, these factors have a cumulatively negative effect on the stone clearance rate after ESWL when they are all unfavorable. In ureteroscopy spatial anatomy has less of a role in regard to stone clearance but it may have a negative impact when there is uniformly unfavorable anatomy.

Adult↗
PubMed1998

The effect of prostate volume, age, total prostate specific antigen level and acute inflammation on the percentage of free serum prostate specific antigen levels in men without clinically detectable prostate cancer.

PURPOSE: We determine the influence of age, prostate volume, total serum prostate specific antigen (PSA) level and histological evidence of acute inflammation in biopsy specimens on the percent free serum PSA level in men without clinically detectable prostate cancer. MATERIALS AND METHODS: We studied 70 men with total PSA levels of 2.6 to 9.9 ng./ml. who had undergone at least 3 sets of prostate biopsies that were negative for cancer as part of our PSA based prostate cancer screening program. Total and free PSA levels were measured using Hybritech immunoassays. Prostate volume and the presence of acute inflammation were determined from the most recent transrectal ultrasonography and prostate needle biopsy. RESULTS: Percent free PSA levels correlated significantly with age (r = 0.48, p = 0.0001) and prostate volume (r = 0.44, p = 0.0002) but not with total PSA (r = 0.04, p = 0.7). The mean percent free PSA did not differ for those with or without acute inflammation. Multivariate regression models demonstrated that age and prostate volume were significant predictors of percent free PSA. CONCLUSIONS: Among men without detectable prostate cancer and a total PSA level between 2.6 and 9.9 ng./ml. percent free serum PSA was higher in older men and in men with a larger prostate gland but was not influenced by total PSA level or the presence of acute inflammation in the prostatic biopsy specimen.

Age Factors↗
PubMed1998

Percentage of free serum prostate-specific antigen as a predictor of pathologic features of prostate cancer in a screening population.

OBJECTIVES: Measurement of the percentage of free prostate-specific antigen (%FPSA) in serum can improve the specificity of prostate cancer screening. We evaluated the ability of %FPSA to predict pathologic features of screen-detected clinically localized prostate cancer. METHODS: We evaluated the correlation between %FPSA in serum before cancer diagnosis and the pathologic features of the cancers detected in 108 men with clinically localized prostate cancer who were treated with radical prostatectomy and for whom complete embedding of the radical prostatectomy specimen was performed. Ninety-seven men (90%) had a previous negative screening evaluation before prostate cancer was detected. RESULTS: There was a negative correlation of %FPSA with penetration of cancer through the prostatic capsule, cancerous surgical margins, Gleason score, percentage of cancer in the gland, and tumor volume (r = -0.2 to -0.4). After controlling for other preoperative predictors, %FPSA predicted capsular penetration (adjusted odds ratio [OR] 1.6, 95% confidence interval [CI] 1.1 to 2.4, for each 5% decrease in %FPSA) and cancer volume 0.5 cc or greater (adjusted OR 1.6, 95% CI 1.1 to 2.3). Preoperative %FPSA also predicted possibly harmless cancer (OR 1.5, 95% CI 1.1 to 2.2, for each 5% increase in %FPSA). CONCLUSIONS: In a select group of men for whom cancer was detected early via screening, a lower %FPSA in serum suggests a potentially more threatening cancer. This information may aid patients and clinicians in making more informed decisions about the management of prostate cancer, such as selecting patients for watchful waiting. However, more research is needed to determine the performance characteristics of %FPSA in clinical practice.

Aged↗
PubMed1998

Use of lower prostate specific antigen cutoffs for prostate cancer screening in black and white men.

PURPOSE: We evaluated differences in the prostate cancer detection rate among black and white men with serum prostate specific antigen (PSA) levels between 2.6 and 4.0 ng./ml., and benign findings on digital rectal examination. MATERIALS AND METHODS: From May 1995 through June 1997 we screened 14,209 white and 1,004 black men 50 years old or older with serum PSA and rectal examinations at 6-month intervals. If PSA was greater than 2.5 ng./ml. or the rectal examination was suspicious for cancer, we recommended an ultrasound guided sextant biopsy of the prostate. We compared differences in clinical characteristics, compliance with the recommendation for biopsy, cancer detection rate, and stage and grade of tumors detected for 924 white and 57 black men. RESULTS: Black men were younger (60 versus 63 years old, p = 0.005) and presented with slightly higher PSA levels (3.3 versus 3.1 ng./ml., p = 0.03) than white men. Overall cancer detection rate was 27% (106 of 391 patients), with cancer detection 2-fold higher among black (13 of 29, 45%) than among white (93 of 362, 26%) men (p = 0.03, odds ratio 2.4, 95% confidence interval 1.1 to 5.1). Controlling for age, total PSA, PSA density, percent free PSA and number of prior screening visits, race remained a significant predictor of cancer (adjusted odds ratio 3.4, confidence interval 1.4 to 8.4). We found trends for worse pathological stage and grade among black men but these differences did not reach statistical significance. CONCLUSIONS: Black race was an independent predictor of prostate cancer even at lower PSA cutoffs (2.6 to 4.0 ng./ml.). Although the positive predictive value for cancer detection was relatively high in black men, long-term outcomes studies are necessary to determine whether the use of lower PSA cutoffs would result in favorable shifts in cancer stage and grade, and a reduction in racial differences in prostate cancer mortality rates.

Aged↗
PubMed1998

Therapy planning as constraint satisfaction: a computer-based antiretroviral therapy advisor for the management of HIV.

We applied the Protégé methodology for building knowledge-based systems to the domain of antiretroviral therapy. We modeled the task of prescribing drug therapy for HIV, abstracting the essential characteristics of the problem solving. We mapped our model of the antiretroviral-therapy domain to the class of constraint-satisfaction problems, and reused the propose-and-revise problem-solving method, from the Protégé library of methods, to build an antiretroviral therapy advisor, ART Critic. Careful modeling and using Protégé allowed us to build a useful and extensible knowledge-based application rapidly.

Anti-HIV Agents↗