bluuebunny/crossref_metadata_2025 huggingface dataset:
A prospective, double‐blind, randomized cross‐over study evaluating changes in urinary pH for relieving the symptoms of interstitial cystitis
Authors: Nguan Christopher , Franciosi Luigi G. , Butterfield Noam N. , Macleod Bernard A. , Jens Martha , Fenster Howard N.
Published: December 2004

OBJECTIVE

To provide evidence for the clinical efficacy of changes in urinary pH on the pain associated with interstitial cystitis (IC).

PATIENTS AND METHODS

A prospective, randomized, double‐blind cross‐over study was conducted with 26 women with IC between 2000 and 2002, consisting of cross‐over instillations of urine at physiological pH (5.0), and neutral buffered pH (NaH2PO4 buffered to pH 7.5). The outcome measured was the subjective symptom of pain assessed using a visual analogue scale at baseline, after the initial instillation of solution, at washout, and after the crossover instillation. Data were analysed using repeated‐measures analysis of variance.

RESULTS

There was no statistically significant difference between the mean (sd) change from baseline pain scores after instilling neutral buffered solution, at 0.50 (2.78), and acidic solution, at 0.33 (3.43) (P = 0.85). Secondary outcomes were analysed, including baseline variability and treatment‐order effects; neither were significantly different between the groups.

CONCLUSIONS

There was no statistically significant difference in subjective pain scores on instilling urine at physiological pH or sodium‐phosphate buffered saline in these patients with IC. Further work is required to define the role, if any, of urinary pH in the pathophysiology and treatment of IC.
Managing patients with an overactive bladder and glaucoma: a questionnaire survey of Japanese urologists on the use of anticholinergics
Authors: Kato Kumiko , Yoshida Kazuhiko , Suzuki Koichi , Murase Tatsuro , Gotoh Momokazu
Published: December 2004

OBJECTIVES

To establish the views of urologists on the use of anticholinergic drugs for treating the overactive bladder (OAB) in patients with glaucoma.

SUBJECTS AND METHODS

In February 2004 a self‐description questionnaire was mailed to all 417 urologists who were members of the Tokai Society of Voiding Dysfunction, to determine current practice in Japan for patients with an OAB and glaucoma. Subgroups were analysed between the types of practice and the duration since the urologists had graduated from medical school.

RESULTS

Of the 155 respondents, 76 (49%) routinely enquired about a history of glaucoma before prescribing anticholinergics, and 45 (29%) routinely referred patients with such a history to ophthalmologists. To treat patients with OAB and glaucoma, 102 (66%) would prescribe anticholinergics if permission were available from the ophthalmologist, 33 (21%) chose other treatments and 17 (11%) abandoned treatment. Forty‐nine urologists (32%) were currently prescribing anticholinergics to patients with glaucoma. As to knowledge about glaucoma, 132 (85%) urologists knew that there were two types of glaucoma and 98 (63%) knew about laser iridotomy. The proportion of urologists who knew of the two types of glaucoma and asked patients for this information was significantly higher in university than in general hospitals (P < 0.05).

CONCLUSIONS

Although anticholinergic drugs can precipitate angle‐closure glaucoma by pupillary block, they are not contraindicated in open‐angle glaucoma or in angle‐closure glaucoma that has already been treated by laser iridotomy. Not all urologists are aware of this difference, at least in Japan. Some urologists avoid anticholinergics in all patients with glaucoma, while others pay little attention to glaucoma. Routine history taking and referral to ophthalmologists allows many patients with OAB and glaucoma to benefit safely from anticholinergics. Moreover, clinicians should be aware of patients with OAB who have not been evaluated by ophthalmologists but who are at risk of angle‐closure glaucoma.
Transurethral resection of the ejaculatory ducts for treating ejaculatory symptoms
Authors: Johnson Christopher W. , Bingham Jonathan B. , Goluboff Erik T. , Fisch Harry
Published: December 2004

OBJECTIVES

To report our experience with transurethral resection of the ejaculatory ducts (TURED) in infertile men with symptomatic ejaculatory duct obstruction (EDO).

PATIENTS AND METHODS

We retrospectively reviewed the operative cases of one urologist from 1995 to 2001, identifying 15 patients with symptomatic EDO who underwent TURED. These men had normal hormone levels and no other known genitourinary dysfunction. Investigations included a history, physical examination, semen analysis, semen culture, and high‐resolution transrectal ultrasonography. Responses to focused questions and semen analysis were evaluated after surgery.

RESULTS

Before surgery, all patients complained of a decrease in the volume of their ejaculate, 14 of 15 had a non‐projectile ejaculation, nine had a genitourinary infection necessitating antibiotic treatment, and five had pain with orgasm. The mean ejaculate volume and total motile sperm count was 1.1 mL and 8.1 million sperm per ejaculate. After surgery, at a mean follow‐up of 2 months, 10 men reported having projectile ejaculation, and eight reported a marked improvement in their sensation of orgasm. Overall, 14 men reported a subjective improvement in their ejaculation. The average postoperative ejaculate volume was 2.3 mL and the total motile sperm count was 38.1 million per ejaculate.

CONCLUSIONS

Men with symptomatic EDO who underwent TURED showed improvements in their ejaculation, sensation of orgasm, semen analysis values and fertility.
Pedicled pubic phalloplasty in females with gender dysphoria
Authors: Bettocchi Carlo , Ralph David J. , Pryor John P.
Published: December 2004

OBJECTIVE

To describe a novel phalloplasty technique and to study the results and complications in female patients with gender dysphoria.

PATIENTS AND METHODS

Between 1989 and 2000, 85 female‐to‐male transsexual patients had a phalloplasty fashioned from suprapubic abdominal wall flap that was tubed to form the phallus, and which incorporated the neourethra made from a pedicled tube of labial skin. The complete neourethral reconstruction was in one stage in 32 patients and in two in 48; five patients did not wish to have the neourethra fashioned.

RESULTS

The cosmetic appearance of the phallus was considered good in 68% of the patients. The major complications (in 60 patients) were related to the neourethra (75%) with stricture formation (64%) and/or fistulae (55%) predominating. This complication rate was significantly less (P < 0.001) when the neourethra was created in two stages. Once the neourethra was completed, patients were then offered both penile and testicular prostheses. Sexual intercourse was possible with no prosthesis in 16 patients.

CONCLUSIONS

The pubic phalloplasty offers an acceptable neophallus without disfiguring the donor skin site. The main complications stem from creating the neourethra and these may be reduced by a two‐stage procedure.
Cavernosal dysfunction in a rabbit model of hyperhomocysteinaemia
Authors: Jones Robert W.A. , Jeremy Jamie Y. , Koupparis Anthony , Persad Raj , Shukla Nilima
Published: December 2004

OBJECTIVE

To investigate the effect of sustained hyperhomocysteinaemia (HHCy) on cavernosal smooth muscle function in a rabbit model of HHCy, developed using a methionine‐enriched diet in which cavernosal responses were characterized, as elevated plasma levels of homocysteine may be a risk factor for vasculogenic erectile dysfunction.

MATERIALS AND METHODS

Six New Zealand White rabbits were fed a diet supplemented with methionine (20 g/kg chow) for 4 weeks, while six control animals were fed a standard diet. Cavernosal strips were mounted in an organ bath and relaxation assessed when stimulated with carbachol, sodium nitroprusside (SNP), or noncholinergic, nonadrenergic (NANC)‐mediated relaxation to electrical‐field stimulation (EFS). Cavernosal tissue cGMP levels were assessed using an enzyme‐linked immunosorbent assay, and superoxide (O2·−) production assessed using an assay of the superoxide dismutase (SOD)‐inhibitable reduction of ferricytochrome c.

RESULTS

The methionine‐rich diet led to an early but sustained HHCy; cavernosal strips from animals after 4 weeks of HHCy had a significantly impaired relaxation response to carbachol, an index of endothelium‐dependent nitric oxide (NO)‐mediated relaxation. This impairment was reversed by incubating with either SOD or catalase. Relaxation with either SNP, an index of endothelium‐independent NO‐mediated relaxation, or NANC‐mediated EFS‐induced relaxation, was unaffected by HHCy. There was a corresponding significant reduction in cavernosal cGMP levels (index of NO activity) in the HHCy group, with a more than five‐fold increase in cavernosal tissue O2·− production.

CONCLUSION

Supplementing the diet of rabbits with methionine for 4 weeks caused an early and sustained HHCy and promoted a marked inhibitory effect on endothelium‐dependent relaxation and NO formation in isolated corpus cavernosum, an effect mediated by reactive oxygen species.
The role of unilateral nephrectomy in the treatment of nephrogenic hypertension in children
Authors: Johal Navroop S. , Kraklau David , Cuckow Peter M.
Published: December 2004

OBJECTIVES

To define the efficacy of unilateral nephrectomy in a large series of patients presenting with renal disease and hypertension, as the latter may be a prominent finding in children with nephrourological disease (renal parenchymal disease, renovascular disease, obstruction, renal dysplasia and cancer).

PATIENTS AND METHODS

We retrospectively reviewed the hospital and outpatient records of 118 children who presented for evaluation with hypertension, and who had a nephrectomy between 1968 and 2003. Patients included in the study were those who had a unilateral nephrectomy for benign renal hypertension with a normal contralateral kidney; in all, 21 had complete records and follow‐up were evaluated. The hypertension was associated with primary renal disease, obstruction and renovascular disease. Blood pressure and medication requirements were compared before and after surgery, the blood pressure values also being compared with published nomograms.

RESULTS

Patients were diagnosed with hypertension at a median age of 5 years and had a nephrectomy at a median of 11 months after the diagnosis. The median follow‐up after surgery was 39 months. Most patients responded well and became normotensive, or there was a reduction in the need for medication. The median time to normalization was 2, 10 and 11 days in patients with primary renal disease, obstruction and renovascular disease, respectively.

CONCLUSION

Nephrectomy is successful in normalizing blood pressure in children with benign renal hypertension and with a normal contralateral kidney.
Growth and stretch response of human exstrophy bladder smooth muscle cells: molecular evidence of normal intrinsic function
Authors: Orsola Anna , Estrada Carlos R. , Nguyen Hiep T. , Retik Alan B. , Freeman Michael R. , Peters Craig A. , Adam Rosalyn M.
Published: December 2004

OBJECTIVE

To establish primary cultures of smooth muscle cells (SMC) from human exstrophic bladders (E‐SMC), and determine their in vitro growth dynamics and responses to mechanical stretch.

MATERIALS AND METHODS

Primary cultures of E‐SMC from three patients were established from exstrophic bladder tissue using an explant method. Growth dynamics were assessed using tetrazolium‐dye uptake. The DNA synthesis rate in response to cyclic stretch‐relaxation was determined with thymidine‐incorporation assays. Expression of the SMC mitogen heparin‐binding epidermal growth factor‐like growth factor (HB‐EGF) mRNA in response to mechanical stretch was determined using semiquantitative reverse transcription‐polymerase chain reaction.

RESULTS

The approximate doubling time of the E‐SMC grown in the presence of serum was 4 days, consistent with growth rates of SMC reported previously. E‐SMC exposed to stretch had greater DNA synthesis, albeit to a lesser extent than previously seen with non‐exstrophic SMC. The expression of HB‐EGF was also increased in cells exposed to mechanical stimuli, consistent with our previous finding of stretch‐regulated HB‐EGF gene expression in bladder SMC.

CONCLUSIONS

E‐SMC had growth characteristics similar to those previously reported in non‐exstrophic cells. E‐SMC also had stretch‐induced expression of HB‐EGF mRNA. These observations provide evidence that despite development in an abnormal defunctionalized state, E‐SMC retain the potential for normal growth, and may modulate this response through mechanisms similar to those operating in normal bladder SMC.
Neuroprotective strategies in radical prostatectomy
Authors: Schiff Jonathan D. , Mulhall John P.
Published: December 2004

In this section, authors from New York give their views on the various neuroprotective strategies for patients having a radical prostatectomy, such as the use of nerve grafts and other approaches. A joint study from Korea, the USA, Canada and the UK is presented in a paper on the importance of patient perception in the clinical assessment and management of BPH. There is also a review of robotic urological surgery. Finally, authors from New York give a review on the life of Isaac Newton. This is a new historical review in the journal, but one that will be of general interest.
The prevalence of renal cell carcinoma diagnosed at autopsy
Authors: Mindrup Steven R. , Pierre Jessica S. , Dahmoush Laila , Konety Badrinath R.
Published: December 2004

OBJECTIVE

To compare the rate of renal cell carcinoma (RCC) detected only at autopsy, from two periods, to determine if the apparent recent increase in RCC in the USA is a true increase or mainly a result of improved imaging techniques, as a true increase in the clinical incidence of RCC should not affect the number of previously undiscovered RCC found only at autopsy.

PATIENTS AND METHODS

We identified all individuals who underwent autopsy in two periods, 1955–60 (3307) and 1991–2001 (2938), and who were indentified with renal tumour either before or after death. Information was obtained on age, sex, histological type and size of tumour, and whether the tumour was identified before or only after death. All cases of RCC detected at autopsy were reviewed for this analysis by one pathologist (L.D.).

RESULTS

Between 1955–60 and 1991–2001 there was a 55% reduction in the mean annual number of autopsies. The proportion of malignant renal masses (RCC) did not change significantly (35.4% to 32.8%). The rate of previously unsuspected RCC detected only at autopsy did not change significantly (0.91 vs 0.72 per 100 autopsies).

CONCLUSION

The number of renal masses, both benign and malignant, discovered only at autopsy is declining, possibly because of better detection before death. However, the rate of occult kidney cancer per 100 autopsies did not change significantly between the two periods, suggesting a true increase in the frequency of clinically detected kidney cancer.
Re‐evaluation of the Tumour‐Node‐Metastasis staging of locally advanced renal cortical tumours: absolute size (T2) is more significant than renal capsular invasion (T3a)
Authors: Murphy Alana M. , Gilbert Scott M. , Katz Aaron E. , Goluboff Erik T. , Sawczuk Ihor S. , Olsson Carl A. , Benson Mitchell C. , McKiernan James M.
Published: December 2004

Authors from Iowa City report on the incidence of RCC; they compared the rate of these tumours at autopsy and felt that the decrease found was a result of better antemortem detection, and an increase with time in the frequency of clinically detected renal cancer.

A study from New York attempted to determine whether size, or transcapsular extension irrespective of size, was more likely to produce an adverse outcome. They analysed their database of 717 such tumours between 1988 and 2002, and found that absolute tumour size was the more significant of the two findings.

OBJECTIVE

To determine which factor was more predictive of adverse outcome in our institutional experience with T2N0M0 and T3N0M0 renal cortical tumours (RCTs) treated surgically, as the current Tumour‐Node‐Metastasis (TNM) staging system for RCTs differentiates between tumours of >7.0 cm but confined to the renal capsule (T2) and tumours that extend through the renal capsule regardless of size (T3a).

MATERIALS AND METHODS

We analysed our institutional database of surgical urological oncology for all patients with T2N0M0 and T3aN0M0 RCT treated with partial or radical nephrectomy from 1988 to 2002. All patients with preoperative metastasis, bilateral or multifocal tumours, nonsporadic disease or benign histology were excluded from analysis. A follow‐up of ≥ 6 months from the time of surgery was required for inclusion. Primary outcomes included local and distant recurrence, and death.

RESULTS

In all, 717 patients had a partial or radical nephrectomy for RCT during the study period. After exclusion criteria were applied, 21 patients with T2N0M0 and 97 with T3aN0M0 tumours were eligible; the median (mean, range) age was 63 (16.6–88.3) years and follow‐up 30.5 (40.8, 6–162) months. The estimated 5‐year disease‐free survival was 68% and 85% for T2N0M0 and T3aN0M0 RCT, respectively (P = 0.002). The 5‐year disease‐specific survival was 81% and 94% for the T2N0M0 and T3aN0M0 groups, respectively (P = 0.085).

CONCLUSION

Patients with T3aN0M0 tumours appear to have better disease‐free and disease‐specific survival than those with T2N0M0 disease, which suggests that tumour invasion through the renal capsule is not as significant as the absolute tumour size.
Radical prostatectomy: pathology findings in 1001 cases compared with other major series and over time
Authors: Bott Simon R.J. , Freeman A. Alex , Stenning Sally , Cohen Jonathan , Parkinson M. Constance ,   THE UROLOGISTS AND PATHOLOGISTS CONTRIBUTING TO THE DATABASE
Published: December 2004

OBJECTIVE

To examine the preoperative features and pathological outcomes of clinical significance of 1001 consecutive essentially unscreened men who had a radical prostatectomy (RP) in the UK between 1988 and 2002, and their changes over time.

PATIENTS AND METHODS

The details of men whose RP specimen was submitted for analysis were entered into the RP database held at the University College Hospital, London; the National Health Service and private patients of 17 surgeons were included. The age, mode of diagnosis, preoperative prostate specific antigen (PSA) level, biopsy and RP findings were compared over time.

RESULTS

The mean (range) age of the men was 62 (40–76) years, the median PSA 8  (0.1–146) ng/mL and the median biopsy Gleason sum score 6; these preoperative features did not change over the study period. The diagnosis of prostate cancer was made by transurethral resection of the prostate alone in 48 men (5%). The maximum number of patients receiving neoadjuvant androgen ablation was 21 (33%) in 1996, and subsequently declined. The median (range) RP Gleason sum score was 7 (4–9). The biopsy Gleason score correlated with the prostatectomy Gleason score in 252 (47%) of 536 men, being lower in 170 (32%) and higher in 113 (21%). The median tumour volume was 2 mL (focus of invasive acini – 31 mL) and the incidence of positive intra‐ and extraprostatic margins was 52%. Both tumour volume and extraprostatic margin positivity declined with time.

CONCLUSIONS

The preoperative features and pathological findings from this UK series are similar to those of other reported cohorts from unscreened populations. The incidence of positive extraprostatic surgical margins, tumour volume and stage decreased with time.
Initial incision of lateral pelvic fascia and early ligation of vascular pedicles during radical prostatectomy: potential to reduce positive margin rates
Authors: Richman Marc , McLaughlin Sean , Maygarden Susan , Pruthi Raj S.
Published: December 2004

OBJECTIVE

To report on our experience with a recently published technique to reduce positive margin (PM) rates (involving early incision of the lateral pelvic fascia, early release of the prostate and Denonvilliers’ fascia off the rectum), with the additional modification of early ligation of the lateral vascular pedicles during radical retropubic prostatectomy (RP), as reducing PM rates continues to be an important oncological goal in RP.

PATIENTS AND METHODS

One hundred consecutive men (mean age 61 years, pretreatment prostate‐specific antigen level 8.9 ng/mL, and estimated blood loss 502 mL) underwent RP by one surgeon. The initial dissection involves early incision of the lateral pelvic fascia and developing the plane between the prostate and underlying rectum, before any apical dissection. This incision can be made medial to the neurovascular bundles in a nerve‐sparing procedure. After this plane is developed, the lateral vascular pedicles to the prostate are also divided. Once these same manoeuvres are used contralaterally, the prostate is lifted off of the rectum and held in place only by the apex and bladder neck. The apical/urethral dissection is then carried out conventionally, followed by dissection/transection of the seminal vesicles and the bladder neck.

RESULTS

The pathological stage included T2a (11%), T2b (69%), T3a (17%), T3b (3%), and N+ (2%); 20 patients had capsular penetration, at the posterolateral (in 15) and anterior aspect (in five) of the gland. The PM rate for the 100 consecutive patients was 13%, with PMs at the apex in 10, the base in two and posterolateral gland in one. No patient had a PM at the site of capsular penetration. When patients were stratified by low‐moderate risk (pT2 and Gleason sum ≤ 7) vs high risk (pT3 or Gleason sum > 7), the PM rates were 7.9% and 29.2%, respectively.

CONCLUSIONS

Initial dissection of the lateral pelvic fascia, including developing a ‘perirectal pocket’, and early ligation of the lateral pedicles, resulted in a low PM rate during RP. This experience supports the previous observations that early development of the pre‐rectal fat plane may allow for more precise dissection below all layers of Denonvilliers’ fascia and with a wider margin of periprostatic tissue.
Evaluating peer support for prostate cancer: the Prostate Cancer Peer Support Inventory
Authors: Steginga Suzanne K. , Pinnock Carole , Gardner Max , (Frank) Gardiner R.A. , Dunn Jeff
Published: December 2004

OBJECTIVE

To develop and test a measure for assessing peer support for men attending prostate cancer support groups, and to describe socio‐demographic, medical and adjustment characteristics of Australian men who attend these support groups.

PATIENTS AND METHODS

In all, 1224 men (51% response) from 44 prostate‐cancer support groups across Australia were recruited by mail. Men completed self‐report measures that included the Prostate Cancer Peer Support Inventory (PCSI), the UCLA Prostate Cancer Index bother scales, psychological distress, quality of life (QoL), bother from pain and tiredness, perception of the clinician's support for group participation. Group‐level variables were also included in the analyses.

RESULTS

Peer support was rated positively by most men; a high satisfaction with support groups was related to better QoL, lower pain, younger age, higher perceived clinician support for group participation, use of alternative therapies, lower education, and regular attendance; dissatisfaction with support groups was related to higher psychological distress, lower QoL, and lower perceived clinician support for group participation. Group variables did not predict positive or negative support. Overall QoL was similar to community norms and psychological distress was low, with only 8% of men reporting high distress. The most common physical symptom was sexual bother, with 74% of men reporting moderate or high bother.

CONCLUSIONS

The PCSI was a useful measure of peer support. Perception of the benefits of peer support was related to individual but not group differences. The clinicians’ attitudes to participation in support groups influenced the men's experience of these groups, and this finding has implications for developing support services for these men.
The economic consequences of prostate and bladder cancer in the UK
Authors: Sangar Vijay K. , Ragavan Narasimhan , Matanhelia Shyam S. , Watson Mike W. , Blades Rosie A.
Published: December 2004

OBJECTIVE

To compare the costs of managing prostate and bladder cancer and relate them to current expenditure on research, as the increasing prevalence of both necessitates the adequate direction of resources.

METHODS

All new prostate and bladder cancers diagnosed in 2001–2002 were identified from British Association of Urological Surgeons Section of Oncology database (national and local). The total cost of diagnosing, treating and following patients for 5 years was estimated as the sum of direct costs (National Health Service) and indirect costs (loss of earnings). Annual research fund allocation (RFA) for each cancer were obtained from the National Cancer Research Institute UK.

RESULTS

There were 15 099 and 7703 patients with newly diagnosed prostate (mean age 72.3 years) and bladder cancers (mean age 71.3 years). The total cost for prostate cancer was estimated at £92.74 million, with hormonal therapy alone costing £63.1 million. The total cost for bladder cancer was £55.39 million, of which superficial disease cost £35.25 million. The mean cost per patient was more for bladder than for prostate cancer (£8349 vs. £7294). The RFA allocation during this period was £20.56 million and £4.62 million for prostate and bladder cancer, respectively, and the respective RFA allotment per pound spent on the mean cost of disease management per patient was £2818 and £553.

CONCLUSION

Individual patient management is more costly for bladder cancer but less is invested in research than for prostate cancer. This study suggests a need to re‐evaluate future strategies.
Parenchymal imaging adds diagnostic utility in evaluating haematuria
Authors: Belani Jay S. , Farooki Aamer , Prasad Srinivasa , Yan Yan , Heiken Jay P. , Kibel Adam S.
Published: December 2004

OBJECTIVE

To compare the findings of renal ultrasonography (US) in the evaluation of patients with and with no haematuria. The increased use of cross‐sectional imaging and US has led to a dramatic improvement in the diagnosis of renal masses, such that computed tomography and/or US have been integrated into the diagnostic evaluation of haematuria, and many more incidental renal lesions are now detected. Thus it is possible that the lesions identified during evaluation for haematuria are incidental, i.e. identified serendipitously, and unrelated to the haematuria.

PATIENTS AND METHODS

We retrospectively compared the US findings obtained from 301 patients referred for new‐onset haematuria to those obtained from 600 patients being evaluated for other than urological reasons. All imaging and patient charts were reviewed to verify the clinical and radiological data.

RESULTS

Haematuria was associated with all renal abnormalities, with an odds ratio (OR, 95% confidence interval) of 4.7 (3.6–7.3). Importantly, haematuria was associated with a renal mass, with an OR of 6.7 (2.8–16.3). Subset analysis revealed that patients with macroscopic and microscopic haematuria had significantly more renal abnormalities (OR 4.7, 2.7–8.2, and 5.3, 3.2–8.8, respectively) and renal masses (OR 7.3, 2.7–20.3, and 6.5, 2.3–18.6, respectively) than controls.

CONCLUSIONS

Both macroscopic and microscopic haematuria are associated with a greater risk of identifying renal lesions. This supports the conclusion that the renal lesions identified with modern imaging techniques during the evaluation of both microscopic and macroscopic haematuria are not serendipitous.
Regional differences in responses of rabbit detrusor to electrical and adrenergic stimulation: influence of outlet obstruction
Authors: Capello Seth A. , Chieh‐Lung Chou Eric , Longhurst Penelope A.
Published: December 2004

OBJECTIVE

To examine regional responses of control and obstructed rabbit detrusor strips to electrical and adrenergic stimulation, and determine whether outlet obstruction causes regional variations in blood flow throughout the detrusor, as the detrusor smooth muscle of the bladder body has previously been considered homogeneous in its pharmacological properties.

MATERIALS AND METHODS

Fourteen male rabbits had the bladder outlet surgically obstructed for 2 weeks and were compared with 10 unoperated control rabbits. Blood flow was measured with the bladder empty and at capacity, using fluorescent microspheres. Paired dorsal and ventral strips were harvested from the midline equatorial detrusor and electrically and adrenergically stimulated.

RESULTS

Obstructed rabbits had significantly higher bladder capacities and bladder weights than control rabbits. Dorsal strips from both control and obstructed rabbits contracted in response to noradrenaline, whereas ventral strips relaxed. The addition of prazosin, a nonselective α1‐adrenergic‐receptor blocker, completely blocked the contraction in dorsal strips, but had no effect on responses of ventral strips. There was also a regional difference in response to electrical stimulation, with ventral strips generating significantly more tension than dorsal strips in both control and obstructed rabbits. There were no regional differences in detrusor blood flow. Obstruction resulted in significantly lower responses to all forms of stimulation, and significantly less blood flow throughout the detrusor.

CONCLUSION

There are regional differences in adrenergic receptor function and response to electrical‐field stimulation throughout control and obstructed rabbit detrusor, a region that was previously thought to be functionally homogeneous. These differences must be recognized and acknowledged to obtain accurate and reproducible data from in vitro studies of the bladder.
Genetic polymorphism of glutathione S‐transferase genes (GSTM1, GSTT1 and GSTP1) and susceptibility to prostate cancer in Northern India
Authors: Srivastava Daya Shankar Lal , Mandhani Anil , Mittal Balraj , Mittal Rama Devi
Published: December 2004

OBJECTIVE

To examine the association of glutathione‐S‐transferase (GST) gene polymorphisms in patients with sporadic prostate cancer, in a North Indian population, as GSTs are active in detoxifying a wide variety of endogenous or exogenous carcinogens, and genetic polymorphisms of GSTM1, GSTT1 and GSTP1 have been assessed to evaluate the relative risk of various cancers.

PATIENTS AND METHODS

We assessed 127 patients with prostate cancer and 144 age‐matched controls, all from North India. The GSTT1 and GSTM1 null genotypes were identified by multiplex polymerase chain reaction (PCR) in peripheral blood DNA samples, and GSTP1‐313 A/G polymorphism was determined by PCR/restriction fragment length polymorphism.

RESULTS

There was a significant association in null alleles of the GSTM1 (odds ratio 2.239, 95% confidence interval 1.37–3.65, P = 0.001) and GSTT1 (1.891, 1.089–3.282, P = 0.026) with prostate cancer risk, and in the ‐313 G alleles (Val) of the GSTP1 gene (2.48, 1.51–4.08, P < 0.001). The combined analysis of these three genotypes showed a further increase in the risks of prostate cancer (7.23, 2.42–22.6, P < 0.001).

CONCLUSION

The GSTP1‐313 G polymorphism, and null alleles of GSTM1 and GSTT1, are strong predisposing risk factors for sporadic prostate cancer in North India.
Differential endostatin binding to bladder, prostate and kidney tumour vessels
Authors: Schmidt Annette , Sommer Frank , Reiner Michael , Klotz Theodor , Engelmann Udo , Addicks Klaus , Bloch Wilhelm
Published: December 2004

OBJECTIVES

To define the anti‐angiogenic mechanism and causes of the heterogeneous influence of endostatin, one of a group of matrix‐derived inhibitors of tumour angiogenesis of increasing significance in tumour treatment, on various tissue types.

MATERIALS AND METHODS

Variations in the binding behaviour of endostatin with vessels were assessed in different tumours (bladder, prostate and kidney) and compared with benign tissue vessels. Biotinylated endostatin was used and detected using extravidin CY3 and extravidin‐gold immunolabelling.

RESULTS

There were significant differences in the number of vessels showing endostatin binding among benign and malignant bladder, prostate and kidney tissues. While there was distinct endostatin binding on a mean (sd) of 94.2 (3.0)% bladder and 73.8 (19.5)% prostate tumour vessels, there was less binding, at 11.32 (3.9)%, on kidney tumour vessels. There was less binding to vessels of benign bladder, prostate and kidney tissue, at 2.0 (1.5), 1.7 (1.7) and 1.5 (1.7)%, respectively. At the ultrastructural level, different binding sites were detected both inside and outside the endothelial cells.

CONCLUSION

Endostatin binds more to all tumour tissues than to benign tissue, but the degree of binding in malignant kidney tissue was significantly less than that in malignant prostate and bladder tissues. These divergent vascular endostatin‐binding patterns could be responsible for a tumour type‐dependent anti‐angiogenic effect attributable to endostatin. Such selective behaviour would have therapeutic consequences for future anti‐angiogenic therapy, in which different kinds of tumours could be further classified into those responding to endostatin or not.
Fast Hybrid Approach for Texturing Point Models
Authors: Zhang Haitao , Qiu Feng , Kaufman Arie
Published: December 2004

We present three methods for texturing point models from sample textures. The first method, the point parameterization method, uses a fast distortion‐bounded parameterization algorithm to flatten the point model's surface into one or more 2D patches. The sample texture is mapped onto these patches and alpha blending is used to minimize the discontinuity in the gaps between the patches. The second method is based on neighborhood matching where a color is assigned to each point by searching the best match within an irregular neighborhood. The hybrid method combines the former two methods, capitalizing on the advantages of both. The point parameterization method is used first to color most of the points, and the point neighborhood‐matching method is then applied to the points belonging to the gaps between the parameterized patches to minimize the discontinuity. We opt for fast texture generation, while some discontinuities may appear in the gaps of anisotropic textures.
Compression of Large‐Scale Terrain Data for Real‐Time Visualization Using a Tiled Quad Tree
Authors: Platings M. , Day A. M.
Published: December 2004

The aim of the rapid world modeling project is to implement a system to visualize the topography of the entire world on consumer‐level hardware. This presents a significant problem in terms of both storage requirements and rendering speed. This paper presents the ‘Tiled Quad Tree’, a technique and format for the storage of digital terrain models, to work as part of an integrated system for the visualization of global terrain data. We show how this format efficiently stores and compresses elevation data, in a way that allows the data to be read very rapidly from hard disk or similar storage medium, to facilitate real‐time rendering. The results of compressing several distinct data sets are presented.
Style‐Based Motion Synthesis†
Authors: Urtasun Raquel , Glardon Pascal , Boulic Ronan , Thalmann Daniel , Fua Pascal
Published: December 2004

Representing motions as linear sums of principal components has become a widely accepted animation technique. While powerful, the simplest version of this approach is not particularly well suited to modeling the specific style of an individual whose motion had not yet been recorded when building the database: it would take an expert to adjust the PCA weights to obtain a motion style that is indistinguishable from his. Consequently, when realism is required, the current practice is to perform a full motion capture session each time a new person must be considered. In this paper, we extend the PCA approach so that this requirement can be drastically reduced: for whole classes of cyclic and noncyclic motions such as walking, running or jumping, it is enough to observe the newcomer moving only once at a particular speed or jumping a particular distance using either an optical motion capture system or a simple pair of synchronized video cameras. This one observation is used to compute a set of principal component weights that best approximates the motion and to extrapolate in real‐time realistic animations of the same person walking or running at different speeds, and jumping a different distance.
Smooth Surface Reconstruction Using Tensor Fields as Structuring Elements
Authors: Vieira M. B. , Martins P. P. , Araújo A. A. , Cord M. , Philipp‐Foliguet S.
Published: December 2004

We propose a new strategy to estimate surface normal information from highly noisy sparse data. Our approach is based on a tensor field morphologically adapted to infer normals. It acts as a three‐dimensional structuring element of smooth surfaces. Robust orientation inference for all input elements is performed by morphological operations using the tensor field. A general normal estimator is defined by combining the inferred normals, their confidences and the tensor field. This estimator can be used to directly reconstruct the surface or give input normals to other reconstruction methods. We present qualitative and quantitative results to show the behavior of the original methods and ours. A comparative discussion of these results shows the efficiency of our propositions.
Stellar Mesh Simplification Using Probabilistic Optimization
Authors: Vieira Antônio W. , Lewiner Thomas , Velho Luiz , Lopes Hélio , Tavares Geovan
Published: December 2004

This paper proposes the stellar mesh simplification method, a fast implementation of the Four‐Face Cluster (FFC) algorithm. In this method, a probabilistic optimization heuristic substitutes the priority queue of the original method, which results in a 40% faster algorithm with the same order of distortion. It extends naturally to a progressive and/or multiresolution scheme for combinatorial surfaces. This work also presents a simple way to encode the hierarchy of the resulting multiresolution meshes. This work also focuses on important aspects for the development of a practical and robust implementation of this simplification technique, and on the analysis of the influence of the parameters.
The “Honest broker” Role and Evaluation Research Affirmed
Authors: Gregory H. Wilmoth
Published: December 2004

This article responds to criticisms of the “honest broker” role of evaluation research done in the positivist tradition. Quantified, statistically representative information frequently has greater utility and perceived credibility than activist research. It also better fits the information needs of policymakers. The roles of evaluations in a dynamic, national policymaking environment are explored. “Mixed results” are shown to be the result of variation in recipients and program implementation as well as assessing multiple outcome variables.
Signaling in Venture Capitalist—New Venture Team Funding Decisions: Does it Indicate Long–Term Venture Outcomes?
Authors: Busenitz Lowell W. , Fiet James O. , Moesel Douglas D.
Published: December 2004

According to signaling theory, new venture teams (NVTs) can communicate to venture capitalists and other potential investors both a “value” signal and a “commitment” signal, based on the level of personal investment in a venture. Venture capitalists (VCs) typically want to know if a NVT is really committed to a venture and if its members truly believe that a venture has wealth creating potential. Team members can convey signals via their investment behavior. We test our hypotheses based on a sample of 183 VC–backed ventures that we tracked over a ten–year time period. These data indicate that the signals sent to VCs in the early stages of the funding process do not appear to have any significant relationship with long–term venture outcomes. We explore possible explanations for these findings, as well as their implications for signaling theory and future research.
Four Bases of Family Business Successor Commitment: Antecedents and Consequences
Authors: Sharma Pramodita , Irving P. Gregory
Published: December 2004

Although successor commitment toward family business has been identified as a key desirable attribute, commitment has been treated as a unidimensional construct in family business research. Drawing on the organizational commitment literature, we propose four bases of successor commitment to family firm—affective (based on perceived desire), normative (based on perceived sense of obligation), calculative (based on perceived opportunity costs involved), and imperative (based on perceived need). A model of antecedents and expected behavioral outcomes of each of these bases of commitment is developed. Related propositions are presented, as are the contributions to the literature, research and practical implications.
Politico–Economic Factors Associated with Interest in Starting a Business: A Multi–Country Study
Authors: Begley Thomas M. , Tan Wee-Liang , Schoch Herbert
Published: December 2004

In this article, we study the constructs of perceived environmental munificence and carrying capacity as they relate to potential for starting a business in samples taken from thirteen Anglo–Saxon, East Asian, and South Asian countries. Seven politico–economic dimensions represent perceived munificence and carrying capacity: financing available, supportive government regulation, market opportunities, access to support services, supply of skilled labor, connections needed, and competitive conditions. Perceived market opportunities, supply of skilled labor, and supportive government regulation (negatively) relate most consistently to start–up feasibility and desirability in the full sample. In regional subsamples, the only dimensions to associate with both feasibility and desirability are market opportunities in Anglo–Saxon countries and supply of skilled labor in South Asia.
The Company You Keep: How Young Firms in Different Competitive Contexts Signal Reputation through Their Customers
Authors: Reuber A. Rebecca , Fischer Eileen
Published: December 2004

This article explores how young firms, across different competitive contexts, signal reputation through their customers. Four distinct competitive contexts were differentiated based on whether the complexity of the customer's purchase process was high or low and whether the product/service was customized or standardized. CEOs of young firms operating in each of the four contexts were interviewed to discern patterns, both within and across contexts, in the reputational signals conferred by customers. Analysis of the interview data yields suggestions for how current theory on the exchange partners of young firms can be refined and extended, as well as propositions related to customer–derived reputation in different competitive contexts.
Not Just Domestic Engineers: An Exploratory Study of Homemaker Entrepreneurs
Authors: Singh Robert P. , Lucas Leyland M.
Published: December 2004

There are millions of homemakers in the United States, but there is scant research on the entrepreneurial activities of this important segment of the population. Using data collected through the Panel Study of Entrepreneurial Dynamics (PSED), this article explores and discusses the significant differences between full–time homemakers who intend to start businesses and a comparison group of non–homemakers who intend to start businesses. In addition to providing a revealing look at this subset of future entrepreneurs, this study illustrates the power of the PSED to allow exploration of unique entrepreneur groups. Following our data analyses, we discuss implications and future research directions to better understand this unique subset of entrepreneurial individuals who are pursuing new ventures.
Prior Knowledge, Potential Financial Reward, and Opportunity Identification
Authors: Shepherd Dean A. , DeTienne Dawn R.
Published: December 2004

This article simultaneously explores the constructs of potential financial reward and prior knowledge of customer problems to provide a deeper understanding of the identification of opportunities. Results suggest that while prior knowledge of customer problems leads to the identification of more opportunities and opportunities that are more innovative, it also moderates the relationship between potential financial reward and opportunity identification. We found that the less knowledgeable an individual was about customer problems, the more positive the effect that potential financial reward had on the number of opportunities identified and the innovativeness of those opportunities.
Evolutionary Processes and Paths of Relationally Embedded Network Ties in Emerging Entrepreneurial Firms
Authors: Hite Julie M.
Published: December 2004

Relationally embedded network ties influence the economic decisions of emerging firms and evolve over time. Evolutionary processes and paths of these ties are examined based on two research questions: How do components of social relationships facilitate the evolution of relational embeddedness? What are the different paths to relational embeddedness? Findings from qualitative case study methods suggest three evolutionary processes (network entry, social component leverage and trust facilitation), four evolutionary paths, and the conclusion that ties entering the network through personal relationship may evolve more quickly toward full embeddedness. Strategic implications for emerging firms are suggested regarding entrepreneurial opportunity recognition, resource acquisition and effective governance of relationally embedded ties.
Respiration tracking in radiosurgery
Authors: Schweikard Achim , Shiomi Hiroya , Adler John
Published: December 2004

Respiratory motion is difficult to compensate for with conventional radiotherapy systems. An accurate tracking method for following the motion of the tumor is of considerable clinical relevance. We investigate methods to compensate for respiratory motion using robotic radiosurgery. In this system the therapeutic beam is moved by a robotic arm, and follows the moving target through a combination of infrared tracking and synchronized x‐ray imaging. Infrared emitters are used to record the motion of the patient's skin surface. The position of internal gold fiducials is computed repeatedly during treatment, via x‐ray image processing. We correlate the motion between external and internal markers. From this correlation model we infer the placement of the internal target during time intervals where no x‐ray images are taken. Fifteen patients with lung tumors have recently been treated with a fully integrated system implementing this new method. The clinical trials confirm our hypothesis that internal motion and external motion are indeed correlated. In a preliminar study we have extended our work to tracking without implanted fiducials, based on algorithms for computing deformation motions and digitally reconstructed radiographs.
DMLC leaf‐pair optimal control of IMRT delivery for a moving rigid target
Authors: Papież Lech
Published: December 2004

In dynamic multileaf collimation (DMLC), pairs of servo‐controlled leaves sweep across the target to deliver the modulated radiation intensity map while the beam is on continuously. The mathematical model for dynamic, optimal control of a single leaf pair has been developed for the case of a rigid target, translating parallel to the leaf trajectories. This mathematical model ensures delivery of the modulated intensity map while minimizing beam‐on time. Numerical solutions of the model are presented here for optimal IMRT delivery for stationary and oscillating targets, together with a discussion of the results. Comparisons between solutions for stationary and mobile targets, as well as comparisons between optimal and suboptimal algorithms, are provided. These comparisons allow us to estimate potential gains in the effectiveness of DMLC IMRT delivery when it is based on optimal algorithms.