bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of test frequency on fatigue strength of low carbon steel
Authors: TSUTSUMI N. , MURAKAMI Y. , DOQUET V.
Published: April 2009

Ultrasonic fatigue tests (test frequency: 20 kHz) and conventional tension–compression fatigue tests (10 Hz) have been conducted on annealed and 10% pre‐strained specimens of 0.13% carbon steel. Small holes were introduced on the specimen surface to investigate the effect of test frequency on small crack growth. The dynamic stress concentration factor and the stress intensity factor under ultrasonic fatigue tests were checked to be almost the same as those of conventional tension–compression fatigue tests. However, the fatigue properties were dependent on the test frequency. Ultrasonic fatigue tests showed longer fatigue life and lower fatigue crack growth rate for the annealed and 10% pre‐strained specimens. Slip bands were scarce in the neighbourhood of cracks under ultrasonic fatigue tests, while many slip bands were observed in a wide area around the crack under conventional fatigue tests. In order to explain the effect of test frequency on fatigue strength, dynamic compression tests with Split Hopkinson bars were carried out. The stress level increases substantially with the strain rate. Thus, the increase in fatigue strength might be, to a large extent, due to a reduction in crack tip cyclic plasticity during ultrasonic fatigue tests.
About cracks, dunce caps and a new way to stop cracks
Authors: MATTHECK C. , BETHGE K. , SAUER A. , SÖRENSEN J. , WISSNER C. , KRAFT O.
Published: April 2009

Recently, the ‘method of tensile triangles’ has been introduced for optimizing the shape of notches by adding material at overloaded regions but also to remove unloaded material from an oversized design proposal.

In this work, we apply the method to demonstrate that the unloaded region in the vicinity of a crack has the shape of spindle‐shaped hole, which looks like two dunce caps mirrored at the crack line. Also, these shapes can be predicted by the ‘method of tensile triangles’ without any FEM‐effort. Furthermore, we show a new way to stop cracks by deviating the crack tip into a shape‐optimized pattern leading to a compressive stress that closes the crack tip. This procedure is now used in chemical engineering.
Modified perineal stapled rectal resection with contour transtar for full‐thickness rectal prolapse
Authors: Romano G. , Bianco F. , Caggiano L.
Published: April 2009

Objective  We report a modified technique of perineal proctectomy using a new reloadable curved cutter stapler, the Contour® TranstarTM (Ethicon Endo‐Surgery), to treat full‐thickness external rectal prolapse.

Method  Between May and July 2008 three female patients were treated. All had a full‐thickness external rectal prolapse up to 10 cm in length. The prolapse was initially divided by a linear cutter in anterior and posterior flaps, and resection of the prolapse was performed with a Contour Transtar stapler.

Results  There was no mortality or early or late morbidity. Follow‐up was 2–4 months. All patients had a bowel movement within 3 days of the operation, oral feeding started immediately and the hospital stay was 5 days in all cases. All patients reported an improvement of constipation and continence.

Conclusion  Our procedure may be indicated for full‐thickness prolapse with a rectal protrusion up to 10 cm, as it allows a simple resection without any mobilization or dissection of the rectum. The technique is safe, easier and faster to perform than conventional perineal rectosigmoidectomy.
Transanal haemorrhoidal artery echodoppler ligation and anopexy (THD) is effective for II and III degree haemorrhoids: a prospective multicentric study
Authors: Infantino A. , Bellomo R. , Dal Monte P. P. , Salafia C. , Tagariello C. , Tonizzo C. A. , Spazzafumo L. , Romano G. , Altomare D. F.
Published: April 2009

Aim  We report a multicentric prospective study which aimed to evaluate Doppler‐assisted ligation of the terminal haemorrhoidal arteries (THD) for II and III degree haemorrhoids.

Method  A total of 112 patients from five colorectal units, including 81 men, mean age 48 ± 13 years, with II degree (39) and III degree (73) haemorrhoids were treated by Doppler‐guided transanal de‐arterialization and anopexy using a new device (THD).

Results  The mean operative time was 33.9 ± 8.8 minutes, and the mean number of ligatures applied was 7.2 ± 1.5. Postoperatively, 72% of patients did not need analgesics and the other 28% used nonsteroidal anti‐inflammatory drugs 1–3 times/day for less than 2 days. All the patients were operated as a day case. Early postoperative complications included haemorrhoidal thrombosis (2 patients), bleeding (1) treated by haemostatic suture, dysuria (6) and acute urinary retention (1). After a mean follow‐up of 15.6 ± 6.5 months (range 6–32), 2/105 (20.9%) patients complained of minor bleeding, while mild pain was still present in 4/51 patients (7.8%). There were no statistically significant differences in the sample population regarding the gender or stage of the disease. Tenesmus was cured in 15/17 patients, dyschaezia in 20/22 patients and mucous soiling in 10/10 patients. No new cases of altered defaecation or faecal incontinence were recorded. Overall, 85.7% of patients were cured and 7.1% improved. Residual haemorrhoids were treated by elastic band ligation in nine (8%) patients and by surgical excision in further five patients (4.5%).

Conclusion  Doppler‐assisted ligation of the terminal branches of the haemorrhoidal arteries for II and III degree haemorrhoids is highly effective and painless. Complications are few and the technique can be performed as a day case.
Cetuximab‐based therapy vs noncetuximab therapy in advanced or metastatic colorectal cancer: a meta‐analysis of seven randomized controlled trials
Authors: Liu L. , Cao Y. , Tan A. , Liao C. , Mo Z. , Gao F.
Published: April 2009

Purpose  A meta‐analysis was performed to assess the efficacy and safety of cetuximab‐based therapy vs noncetuximab therapy in advanced or metastatic colorectal cancer.

Method  A total of 4617 patients from seven randomized controlled trials were available for analysis, with 2305 patients in the cetuximab group and 2312 patients in the noncetuximab group. The efficacy data included progression‐free survival (PFS), overall survival (OS) and overall response rate (ORR). The safety data that contained overall grade 3 and 4 adverse events (AEs), specific grade 3 and 4 toxicity such as acneiform rash, cetuximab‐related skin toxicity, diarrhoea, fatigue, neutropenia, hypertension, nausea and hand–foot skin reaction are evaluated.

Result  There was a significant PFS benefit in favour of cetuximab‐based therapy (HR = 0.68, 95%CI: 0.63 to 0.73) and OS benefit (HR = 0.90, 95%CI: 0.81 to 1.00). The ORR was significantly higher in the cetuximab‐based arm (OR = 2.19, 95% CI: 1.30 to 3.68). The incidence of overall grade 3–4 toxicity was significantly higher in the cetuximab arm compared with the noncetuximab arm (61.2%vs 43.0%, OR = 2.32, 95%CI: 1.59–3.39). This difference was mainly attributed to cetuximab‐related skin toxicity (OR = 5.86, 95%CI: 1.38–24.88), especially acneiform rash (OR = 51.37, 95%CI: 22.75–116.02). In addition, cetuximab resulted in a significant increase in grade 3 and 4 diarrhoea, fatigue and neutropenia, except for hypertension, nausea and hand–foot skin reaction.

Conclusion  Cetuximab‐based therapy improves PFS and OS resulting in better ORR vs noncetuximab therapy. Its most common and severe AE is skin toxicity that should be predictable and manageable.
The role of metabolic derangements and glucocorticoid excess in the aetiology of cognitive impairment in type 2 diabetes. Implications for future therapeutic strategies
Authors: Strachan Mark W. J. , Reynolds Rebecca M. , Frier Brian M. , Mitchell Rory J. , Price Jacqueline F.
Published: April 2009

Dementia is becoming increasingly common in western societies and carries with it a substantial clinical, social and economic burden. It is now well established that type 2 diabetes is a risk factor for dementia and it is likely that this association has a multifactorial aetiology. There is a relative paucity of data on interventions to improve cognitive function in people with type 2 diabetes. Two small randomized controlled trials have suggested that better glycaemic control, over a relatively short time period, can improve or prevent decline in cognitive function. There is also increasing interest in the link between intracerebral insulin and cognitive impairment. Several studies have suggested that relative and/or absolute deficiency of insulin may occur in Alzheimer’s dementia and, although one small randomized trial was essentially negative, randomized trials are currently underway to investigate the impact of thiazolidinediones on cognitive function in dementia. The hypothalamic–pituitary–adrenal axis is also activated in people with type 2 diabetes and there are data linking increased cortisol concentrations with cognitive impairment. Inhibition of the 11 β‐hydroxysteroid dehydrogenase type 1 enzyme, which generates cortisol from inactive cortisone in many tissues including the brain, is an attractive therapeutic target to enhance cognition. Large‐scale epidemiological and intervention studies are now underway, which should enhance our understanding and management of cognitive impairment in type 2 diabetes.
Successful switch from insulin therapy to treatment with pioglitazone in type 2 diabetes patients with residual β‐cell function: results from the PioSwitch Study
Authors: Hohberg C. , Pfützner A. , Forst T. , Lübben G. , Karagiannis E. , Borchert M. , Schöndorf T.
Published: April 2009

Aim:  Insulin treatment is considered to be the final option for patients with progressive type 2 diabetes. This study investigated, whether reconverting type 2 patients from insulin treatment to oral treatment using pioglitazone is possible without deterioration of blood glucose control.

Methods:  The PioSwitch study was a prospective, open label, proof of concept study. Thiazolidinedione‐naïve patients with residual β‐cell function were switched from an existing insulin therapy to treatment with pioglitazone and glimepiride for 6 months. Efficacy was assessed by laboratory parameters and scores for evaluation of metabolic control, β‐cell function, insulin resistance and cardiovascular risk.

Results:  In total, 98 patients [66 men, 32 women, age (mean ± s.d.): 59 ± 9 years; disease duration: 5.6 ± 3.6 years; Hemoglobin A1c (HbA1c): 6.9 ± 0.8%; body mass index (BMI): 33.9 ± 5.2 kg/m2, initial daily insulin therapy dose: 0.36 ± 0.3 U/kg body weight] out of 117 screened patients were treated. During the observation period, 23 patients were prematurely terminated because of an increase in HbA1c from baseline > 0.5% or other reasons. In 75 patients (76%), no deterioration of glucose metabolism occurred and additional improvements were seen in the majority of the observation parameters [baseline vs. endpoint; HbA1c: 6.79 ± 0.74%/6.66 ± 0.69% (p < 0.05), glucose: 6.4 ± 1.5/5.2 ± 1.4 mmol/l (p < 0.001), adiponectin: 7 ± 3 mg/l/17 ± 8 mg/l (p < 0.001), C‐peptide: 987 ± 493/1756 ± 789 (p < 0.001), sensitivity index derived from the intravenous glucose tolerance test (SI(ivGTT)): 1.21 ± 0.85/1.49 ± 0.95 (p < 0.05), hsCRP: 3.3 ± 2.4/2.6 ± 2.4 mg/l (p < 0.01), macrophage chemo‐attractant protein 1 (MCP1): 487 ± 246/382 ± 295 ng/l (p < 0.05)]. BMI increased from 33.8 ± 5.1 to 34.4 ± 5.3 kg/m2 (p < 0.001).

Conclusions:  The switch from insulin therapy resulting in a moderately HbA1c level, to oral treatment with pioglitazone was successful in a majority of patients with sufficient residual β‐cell function. It allows a simple and less expensive therapy with a better cardiovascular risk marker profile.
Reproducibility of hepatic triglyceride content assessment in normals using localized magnetic resonance spectroscopy
Authors: Kullberg J. , Ortiz‐Nieto F. , Johansson L.
Published: April 2009

Aim:  To investigate the reproducibility of measurements of hepatic triglyceride content (HTGC) in subjects with normal HTGC using localized 1H‐magnetic resonance spectroscopy (1H‐MRS) and a clinical 1.5T scanner.

Methods:  The 1H‐MRS acquisition was performed with a common protocol using the whole‐body coil and no respiratory triggering. An upper limit of normal HTGC of 5.56% was used. Duplicate measurements, including subject repositioning, were acquired from 23 subjects, 19 of whom had a normal HTGC.

Results:  The mean coefficient of variation (CV) from the duplicate measurements was 14.8% (20.5% before exclusion of a subject who was considered to be an outlier). Mean CVs of subgroups below and above the 1% HTGC limit were 19.8 and 7.0 respectively.

Conclusions:  The mean CV calculated in subjects with HTGC in the normal range was found to be higher than CVs of wide range HTGC groups reported in the literature. It is concluded that the reproducibility of HTGC measurements using 1H‐MRS depends on the HTGC range. These findings are of importance in reproducibility studies and in estimations of required study group sizes.
Improvement in quality of life after botulinum toxin‐A injections for idiopathic detrusor overactivity: results from a randomized double‐blind placebo‐controlled trial
Authors: Sahai Arun , Dowson Christopher , Khan Mohammad S. , Dasgupta Prokar
Published: April 2009

OBJECTIVE

To determine whether botulinum toxin‐A (BTX‐A) treatment has an effect on the quality of life (QoL) of patients with overactive bladder (OAB) refractory to anticholinergics.

PATIENTS AND METHODS

This was a single centre, randomized, double‐blind, placebo‐controlled trial. Participants were men and women with idiopathic detrusor overactivity (IDO). Participants were randomised to receive either 200 U of BTX‐A (Botox®, Allergan Inc., Irvine, CA, USA; n = 16) or placebo (n = 18) via a trigone‐sparing flexible cystoscopic technique. QoL was assessed using the King’s Health Questionnaire (KHQ) at baseline and at 4 and 12 weeks, after injection. At 12 weeks patients were ‘unblinded’ and a further open‐label follow‐up in the BTX‐A group occurred at 24 weeks. The changes in the subdomains of the KHQ were assessed over the study period.

RESULTS

Overall QoL was significantly improved in the BTX‐A treated patients compared with placebo in the blinded part of the study. When analysing the KHQ subdomains, ‘Incontinence Impact’, ‘Emotions’, ‘Physical Limitations’, ‘Social Limitations’ and ‘Severity Measures’ were significantly improved in those that received BTX‐A compared with placebo. The ‘Symptom Severity’ domain was also significantly improved at 4 weeks but not at 12 weeks. At 12 weeks ‘Role Limitations’ also became statistically significant in favour of BTX‐A. The open‐label extension study suggested these benefits last for at least 24 weeks.

CONCLUSIONS

BTX‐A bladder injections at 200 U appear to improve QoL in patients with OAB symptoms and IDO refractory to anticholinergics for at least 24 weeks. As well as the improvement seen in clinical parameters with this form of therapy, perhaps of more importance to the patient, is the improvement in QoL.
Nephrectomy improves survival in patients with invasion of adjacent viscera and absence of nodal metastases (stage T4N0 renal cell carcinoma)
Authors: Capitanio Umberto , Perrotte Paul , Zini Laurent , Jeldres Claudio , Shariat Shahrokh F. , Isbarn Hendrik , Arjane Philippe , Peloquin François , Pharand Daniel , Montorsi Francesco , Karakiewicz Pierre I.
Published: April 2009

OBJECTIVE

To examine the cancer‐specific mortality (CSM) of patients with T4N0–2M0 renal cell carcinoma (RCC) treated with either nephrectomy (RN) or no surgery (NS).

PATIENTS AND METHODS

Of 43 143 patients with RCC identified in the Surveillance, Epidemiology and End Results database, 310 had tumours involving adjacent organs with no evidence of distant metastases (T4NanyM0) and had RN (246, 79.4%) or NS (64, 20.6%). Kaplan‐Meier analyses, Cox regression and competing‐risks regression models were used to compare the effect of RN vs NS on CSS.

RESULTS

In patients with T4N0 disease the median survival benefit associated with RN vs NS was 42 months (48 vs 6 months, P < 0.001). Conversely, the median survival in patients T4N1‐2 was no different between RN and NS (9.3 vs 9.1 months, P = 0.9). Multivariable analyses in T4N0 cases indicated a substantial survival disadvantage for patients having NS vs RN (hazard ratio 4.8, P < 0.001). Conversely, in patients with N1‐2 stages, the CSS was virtually the same for NS and RN (hazard ratio 0.9, P = 0.9). Competing‐risks regression models confirmed the benefit of RC in patients with T4N0 and the lack of benefit in those with T4N1‐2 disease, after controlling for other‐cause mortality.

CONCLUSION

Our data suggest a survival benefit in patients with T4N0 RCC treated with RC. By contrast, RN seems to have no effect on survival in patients with evidence of nodal metastases.
Ureteric response to abdominal radiotherapy and metallic double‐pigtail ureteric stents: a pig model
Authors: Liatsikos Evangelos , Kyriazis Iason , Kallidonis Panagiotis , Tsamandas Athanasios , Karnabatidis Dimitrios , Sakellaropoulos Georgios , Flaris Nicolaos , Kalogeropoulou Christina , Filos Kriton , Stolzenburg Jens‐Uwe , Kardamakis Dimitrios
Published: April 2009

OBJECTIVE

To examine the safety and compatibility of full‐length metal ureteric stents with abdominal radiotherapy.

MATERIALS AND METHODS

Four ureteric stents (ResonanceTM, Cook Urological, Ireland) (RS) and four RSs specially modified to contain thermocouples were placed unilaterally in eight pigs. The contralateral ureters of the same pigs served as their controls, and contained two polymeric ureteric catheters and two similar specially modified to contain thermocouples, while the remaining four control ureters remained intact. All pigs were exposed to abdominal radiotherapy. The dose rate was ≈5.3 Gy/min and a total radiation dose of 10 Gy was administered. Throughout the treatment the temperature was monitored by the RSs and catheters containing the thermocouples. The pigs were killed at 1 day (four), 7 days (two) and 15 days (two) after treatment, and all ureters examined histologically.

RESULTS

There was no statistically significant increase in RS and catheter temperature throughout the treatment in any of the treated pigs (P > 0.05). All histological lesions reported were due to radiation treatment. There were no differences in histology between the ureters containing RSs and controls.

CONCLUSION

RS usage is unrelated to any increase in stent temperature during abdominal radiotherapy and does not cause any further deterioration in the histology of the ipsilateral ureter, additional to that caused by the initial treatment.
Activation of the mammalian target of rapamycin signalling pathway in prostate cancer and its association with patient clinicopathological characteristics
Authors: Dai Bo , Kong Yun Yi , Ye Ding Wei , Ma Chun Guang , Zhou XiaoYan , Yao Xu Dong
Published: April 2009

OBJECTIVE

To evaluate the activation level of the mammalian target of rapamycin (mTOR) signalling pathway in Chinese patients with prostate cancer, as this pathway is over‐activated in many human cancers and is an attractive target for cancer therapy.

PATIENTS AND METHODS

We used immunohistochemistry to investigate the activation level of five important markers of the mTOR pathway, including PTEN, p‐Akt, p‐mTOR, p‐p70S6K and p‐4E‐BP1, in tissues from 182 patients with prostate cancer, 20 with benign prostatic hyperplasia (BPH) and 10 with high‐grade prostatic intraepithelial neoplasia (HGPIN). The expression levels of these five markers were associated with patient clinical and pathological characteristics.

RESULTS

Expression levels of p‐Akt, p‐mTOR, p‐4E‐BP1 and p‐p70S6K were significantly higher in prostate cancer tissues than in BPH and HGPIN tissues. In 182 patients with prostate cancer the p‐mTOR expression level significantly and positively correlated with its upstream p‐Akt and downstream p‐4E‐BP1 and p‐p70S6K expression levels. The cancer Gleason score was significantly correlated with p‐Akt and p‐mTOR expression level but not with p‐4E‐BP1 and p‐p70S6K expression level. However, the p‐4E‐BP1and p‐p70S6K expression levels in primary cancer lesions were statistically significantly correlated with patient T stage and distant metastases.

CONCLUSIONS

Most patients with prostate cancer have at least one component of the mTOR signalling pathway activated. The activation of the mTOR pathway might be involved in prostate cancer development and progression. The association between activation of mTOR pathway and patient clinicopathological variables suggested that not all patients are equally amenable to treatment strategies targeting the mTOR pathway.
A single‐institution experience with induction and maintenance intravesical docetaxel in the management of non‐muscle‐invasive bladder cancer refractory to bacille Calmette‐Guérin therapy
Authors: Barlow LaMont , McKiernan James , Sawczuk Ihor , Benson Mitchell
Published: April 2009

OBJECTIVE

To analyse the durability of response for patients with non‐muscle‐invasive bladder cancer (NMIBC) refractory to bacille Calmette‐Guérin (BCG) therapy and treated with intravesical docetaxel in a combined induction and maintenance regimen.

PATIENTS AND METHODS

A previous phase I trial showed docetaxel to be safe for intravesical therapy, with no systemic absorption and minimal toxicity after six weekly instillations for patients with BCG‐refractory NMIBC. In that trial, docetaxel gave a 56% complete response (CR) rate at 12 weeks, but the durability was only 22%. Thus a second group of patients was treated with a 6‐week induction and then given monthly maintenance therapy with intravesical docetaxel. Thirteen patients with BCG‐refractory Ta, T1, or Tis transitional cell carcinoma were treated. Induction therapy was administered as six weekly intravesical instillations of 75 mg followed by single‐dose monthly maintenance therapy for nine additional instillations in patients who had a CR. The initial response at 12 weeks from the start of induction therapy was evaluated by cystoscopy with biopsy, and urine cytology. The follow‐up consisted of quarterly cystoscopy with biopsy and cytology, and periodic imaging.

RESULTS

The median follow‐up was 13 months; 10 of 13 patients had a CR after induction, and six have remained disease‐free during the follow‐up. Of those in who the treatment failed, six had transurethral resection of the tumour and one a cystectomy. All 10 initial responders completed at least three instillations of maintenance therapy to date (median nine instillations), of whom six have remained recurrence‐free.

CONCLUSION

Monthly maintenance therapy with intravesical docetaxel appears to extend the durability of response to induction treatment for a selected group of patients with BCG‐refractory NMIBC, and might decrease the overall risk of recurrence in high‐risk NMIBC.
Xanthogranulomatous pyelonephritis: presentation and management in the era of laparoscopy
Authors: Guzzo Thomas J. , Bivalacqua Trinity J. , Pierorazio Phillip M. , Varkarakis John , Schaeffer Edward M. , Allaf Mohamad E.
Published: April 2009

OBJECTIVE

To report a contemporary series of patients with xanthogranulomatous pyelonephritis (XGP, an inflammatory condition of the kidney that has traditionally been treated with open nephrectomy, ON), managed with either ON or laparoscopic nephrectomy (LN), as early reports suggest that the benefits of LN do not extend to patients with XGP.

PATIENTS AND METHODS

The medical and procedural records of patients with pathologically confirmed XGP between December 1993 to February 2004 were reviewed retrospectively. During this period, 26 patients (mean age 43.5 years, range 17–85) had surgical management of XGP; information on the mode of presentation, surgical management, hospital course and complications were analysed.

RESULTS

Twelve (46%) and 14 (54%) patients had ON and LN, respectively. The LN group had significantly lower blood loss (P = 0.002), transfusion rates (P = 0.02), time to resumption of oral intake (P = 0.002) and length of hospital stay (P = 0.002) than the ON group. One (7%) LN was converted to ON due to failure to progress. The overall complication rates between the ON and LN groups were not significantly different (P = 0.95).

CONCLUSIONS

LN in the setting of XGP is often difficult and requires advanced laparoscopic skills. In highly selected patients this approach can be offered, with acceptable morbidity, allowing for lower blood loss and shorter convalesce times.
Tumour length of the largest focus predicts prostate‐specific antigen‐based recurrence after radical prostatectomy in clinically localized prostate cancer
Authors: Mizuno Ryuichi , Nakashima Jun , Mukai Makio , Okita Hajime , Kosugi Michio , Kikuchi Eiji , Miyajima Akira , Nakagawa Ken , Ohigashi Takashi , Oya Mototsugu
Published: April 2009

OBJECTIVE

To investigate the possible significance of tumour dimensional variables, including maximum tumour diameter (MTD), maximum tumour area (MTA) and total tumour volume (TTV), with standard prognostic factors for predicting prostate‐specific antigen (PSA) recurrence after radical prostatectomy (RP).

PATIENTS AND METHODS

Serial whole sections of the prostate from 164 patients who had RP for localized prostate cancer were investigated. Cox proportional hazards regression models were used for univariate and multivariate analyses to test the relationships between biochemical failure and clinicopathological factors, including tumour dimensional variables. The results were analysed retrospectively to develop a prognostic factor‐based model for risk stratification.

RESULTS

In the univariate Cox proportional hazard model, pathological T stage, Gleason score, perineural invasion, microvascular invasion, positive surgical margins, MTD, MTA and TTV were significantly associated with biochemical failure. In the multivariate Cox proportional hazard model using a stepwise inclusion of these factors, Gleason score, positive surgical margins and MTD were independent indices in association with biochemical failure. Using the three statistically significant variables, the relative risk of biochemical failure could be calculated.

CONCLUSION

These results imply that MTD is possibly one of the most important prognostic factors for predicting biochemical recurrence after RP. As calculating the MTD on the section a rapid, simple and objective method, it can be used instead of the TTV calculation. The prognostic factor‐ based risk stratification might help clinicians to predict biochemical failure after RP.
Impact of ethnicity on surgical margins at radical prostatectomy
Authors: Rabbani Farhang , Herran Yunis Luis , Vora Kinjal , Eastham James A. , Guillonneau Bertrand , Scardino Peter T. , Touijer Karim
Published: April 2009

OBJECTIVE

To determine if the rate of positive surgical margins (PSMs), and in particular apical PSMs, at radical prostatectomy (RP) for prostate cancer, is higher in African‐American (AA) than Caucasian men, given their often narrower and deeper pelvis.

PATIENTS AND METHODS

From 1999 to 2007, 3145 consecutive patients underwent RP, either open retropubic (RRP) or laparoscopic (LRP), with no previous treatment, by one of five surgeons. Multivariate logistic regression was used to determine the effect of ethnicity (AA vs Caucasian) on overall and site‐specific PSMs, adjusting for age, body mass index, RP approach (RRP vs LRP), surgeon, surgeon case number, year of surgery, preoperative serum prostate‐specific antigen level, specimen weight, estimated blood loss, pathological organ‐confined status, and pathological Gleason score.

RESULTS

In all, 205 men were AA and 2940 Caucasian; PSMs were identified in 376 (12.0%) men, 35 (17.1%) in AA and 341 (11.6%) in Caucasian men. PSMs were identified at the apex in 148 (4.7%), the bladder neck in 29 (0.9%), posteriorly in 169 (5.4%), and anteriorly in 78 (2.5%) men. For apical PSM, ethnicity was a significant predictor, with an odds ratio of 1.76 (95% confidence interval 1.01–3.04, P = 0.045) for AA vs Caucasian, independent of pathological organ‐confined status and PSA level. Ethnicity was not a significant independent predictor of overall PSMs or PSMs at other sites (bladder neck, posteriorly, or anteriorly).

CONCLUSIONS

The rate of apical PSMs, but not overall PSMs, at RP was higher in AA than Caucasian men, controlling for other covariates. Further investigation is necessary to determine if pelvic shape is responsible for this observation.
Outcomes of patients undergoing radical cystoprostatectomy for bladder cancer with prostatic involvement on final pathology
Authors: Barocas Daniel A. , Patel Sanjay G. , Chang Sam S. , Clark Peter E. , Smith Joseph A. , Cookson Michael S.
Published: April 2009

OBJECTIVE

To evaluate the impact of prostatic urothelial carcinoma (PUC) on survival of patients with bladder cancer undergoing radical cystoprostatectomy (RCP).

PATIENTS AND METHODS

From 1998 to 2005, 463 consecutive RCPs were performed for UC of the bladder. Patients with PUC at final pathology were grouped by route of prostatic invasion (bladder origin or prostatic urethral origin) and by depth of invasion (carcinoma in situ, ductal invasion, and stromal invasion). Univariate and multivariate survival analyses were performed.

RESULTS

In all, 35% (162/463) of patients had PUC. The 3‐year overall survival (OS) was 58.2% for patients who did not have PUC, 59.2%, 51.7%, and 16.8% in order of increasing depth of prostatic invasion for patients with PUC of urethral origin, and 6.7% for patients with bladder‐origin PUC. Survival differed significantly between stromal and non‐stromal PUC (P < 0.001). Patients with PUC of bladder origin had a higher rate of positive lymph nodes (LNs) than patients with stromal PUC of prostate origin (74.3% vs 27.8%, P < 0.001), but survival was similar (P = 0.619). On multivariate analysis, age (P = 0.035), increasing bladder stage (P = 0.003), stromal invasion (P = 0.002) and positive LNs (P < 0.001) were predictors of poor OS.

CONCLUSION

Depth of prostatic invasion correlates with outcome. While prostatic involvement originating in the bladder is associated with higher rates of positive LNs, survival is similar to patients with stromal involvement of urethral origin. Age, bladder tumour stage, prostatic stromal involvement and positive LNs predict adverse outcome. Our data support separate staging of the prostate in RCP specimens.
Vitamin D repletion does not alter urinary calcium excretion in healthy postmenopausal women
Authors: Penniston Kristina L. , Jones Andrea N. , Nakada Stephen Y. , Hansen Karen E.
Published: April 2009

OBJECTIVE

To evaluate, in a posthoc analysis of a previous study, whether vitamin D repletion in postmenopausal women with insufficient vitamin D increases urinary calcium excretion, as vitamin D therapy might contribute to hypercalciuria and calcium stones in susceptible individuals, and the effect of vitamin D on the risk of urolithiasis warrants attention.

SUBJECTS AND METHODS

We recruited 18 women at ≥5 years after menopause who had vitamin D insufficiency (serum 25(OH)‐vitamin D, 16–24 mg/dL). We excluded women with a history of urolithiasis and kidney disease. Women had one calcium absorption study when vitamin D‐insufficient, received vitamin D therapy, and completed a second calcium absorption study when vitamin D‐replete. We fed subjects meals that mirrored the nutrient composition from self‐reported 7‐day diet diaries. To measure calcium absorption, we collected urine for 24 h during both visits.

RESULTS

We achieved vitamin D repletion in all women (25(OH)‐vitamin D before and after treatment, 22 and 63 mg/dL, respectively; P < 0.001). The mean calcium intake was 832 mg/day. Residual urine specimens were available for 16 women, allowing a measurement of 24‐h urinary calcium. Calcium excretion did not change after vitamin D therapy (212 before vs 195 mg/day after; P = 0.60). Of four women with hypercalciuria (>247 mg/day), calcium excretion decreased in three (377–312 mg/day, not significant).

CONCLUSION

Vitamin D supplementation did not increase the urinary calcium excretion in healthy postmenopausal women. Many stone formers are at risk of premature bone loss, vitamin D insufficiency, or both. Based on the present results we suggest a study of patients with hypercalciuria and nephrolithiasis to determine the risks of vitamin D therapy.
Safety and efficacy of sildenafil citrate in treating erectile dysfunction in patients with combat‐related post‐traumatic stress disorder: a double‐blind, randomized and placebo‐controlled study
Authors: Safarinejad Mohammad Reza , Kolahi Ali Asgar , Ghaedi Gholamhossein
Published: April 2009

OBJECTIVE

To evaluate the safety and efficacy of sildenafil citrate for treating erectile dysfunction (ED) in patients with combat‐related post‐traumatic stress disorder (PTSD).

PATIENTS AND METHODS

In all, 266 combat‐exposed war veterans with ED (aged 37–59 years) were recruited. They met the Diagnostic and Statistical Manual of Mental Disorders‐IV criteria for PTSD according to the Structured Clinical Interview for Patients, Investigator Version. The patients were also evaluated with the Clinician‐Administered PTSD Scale, both to establish the diagnosis of PTSD and to measure symptom severity. Only patients with psychogenic ED were included in the study. Patients with comorbid conditions (diabetes mellitus, hypercholesterolaemia, hypertension, Peyronie’s disease) and smokers of more than five cigarettes daily were excluded. The patients were randomly divided into a group of 133 who received 100 mg of on‐demand sildenafil 0.75–2 h before sexual stimulation, and 133 who received placebo. Patients were asked to use ≥16 doses or attempts at home. The efficacy of the treatments was assessed every four attempts during treatment, and at the end of the study, using responses to the 15‐question International Index of Erectile Function (IIEF), Sexual Encounter Profile diary questions 2 and 3, Erectile Dysfunction Inventory of Treatment Satisfaction questionnaire, patients’ event logs of sexual activity, and a Global Assessment Question about erections.

RESULTS

Sildenafil did not produce significantly and substantially greater improvement than placebo in each of the primary and secondary outcome measures (P = 0.08). A normal EF domain score (≥26) at endpoint was reported by 13 (9.8%), and 11 (8.3%) of patients on the sildenafil and placebo regimens, respectively (P = 0.09). Patients treated with sildenafil had no statistically significantly greater improvement in the five sexual function domains of the IIEF questionnaire than those treated with placebo (P = 0.08). The incidences of treatment‐emergent adverse events were significantly greater in the sildenafil arm than in the placebo group (P = 0.01).

CONCLUSIONS

Sildenafil is no better than placebo in treating PTSD‐emergent ED. Further randomized clinical trials are warranted in combat veterans and other populations with PTSD to better elucidate the role of phosphodiesterase type 5 inhibitors in treating PTSD‐emergent ED.
Longitudinal studies of time‐dependent changes in both bladder and erectile function after streptozotocin‐induced diabetes in Fischer 344 male rats
Authors: Melman Arnold , Zotova Elena , Kim Mimi , Arezzo Joseph , Davies Kelvin , DiSanto Michael , Tar Moses
Published: April 2009

OBJECTIVES

To provide sensitive physiological endpoints for the onset and long‐term progression of deficits induced by diabetes mellitus (DM) in bladder and erectile function in male rats, and to evaluate parallel changes in urogenital and nerve function induced by hyperglycaemia over a protracted period as a model for chronic deficits in patients with diabetes.

MATERIALS AND METHODS

The study comprised in 877 male, 3‐month‐old, Fischer 344 rats; 666 were injected intraperitoneally with 35 mg/kg streptozotocin (STZ) and divided into insulin‐treated and untreated diabetic groups. The rats were studied over 8 months and measurements made of both erectile and bladder function, as well as nerve conduction studies over the duration of the study.

RESULTS

There was an early (first month) abnormality of both erectile and bladder function that persisted through the 8 months of the study. The erectile dysfunction was manifest as reduced intracavernous pressure/blood pressure ratio, and the bladder dysfunction as a persistent increase in detrusor overactivity with no detrusor decompensation. Insulin treatment prevented or modified the abnormality in each organ. Hyperglycaemia caused a progressive decrease in caudal nerve conduction velocity. The mean digital sensory and tibial motor nerve conduction velocity did not deteriorate over time. Correlation measurements of nerve and organ function were not consistent.

CONCLUSIONS

The results of this extensive long‐term study show early and profound effects of hyperglycaemia on the smooth muscle of the penis and bladder, that were persistent and stable in surviving rats over the 8 months. The physiological changes did not correlate well with neurological measurements of those organs. Significantly, diverse smooth‐muscle cellular and subcellular events antedated the measured neurological manifestations of the hyperglycaemia by several months. Although autonomic diabetic neuropathy is a primary life‐threatening complication of long‐term diabetes in humans, this rat model of STZ‐induced diabetes showed that the rapid onset of physiological manifestations was based on many molecular changes in the smooth muscle cells in this model of type 1 DM.
Learning in virtual worlds: Using communities of practice to explain how people learn from play
Authors: Oliver Martin , Carr Diane
Published: April 2009

Although there is interest in the educational potential of online multiplayer games and virtual worlds, there is still little evidence to explain specifically what and how people learn from these environments. This paper addresses this issue by exploring the experiences of couples that play World of Warcraft together. Learning outcomes were identified (involving the management of ludic, social and material resources) along with learning processes, which followed Wenger's model of participation in Communities of Practice. Comparing this with existing literature suggests that productive comparisons can be drawn with the experiences of distance education students and the social pressures that affect their participation.
Exploring the educational potential of virtual worlds—Some reflections from the SPP
Authors: Twining Peter
Published: April 2009

This paper describes and reflects on the development of the Schome Park Programme (SPP), which was established with the specific aim of extending our thinking about schome, which aims to be the optimal educational system for the 21st century.

In an earlier stage of the Schome Initiative, it became clear that people find it almost impossible to break free from established conceptions of education. Open virtual worlds like Second Life® virtual world offer opportunities for people to have radically different ‘lived experiences’ of educational systems and thus seemed to be the ideal vehicle for exploring alternative models of education. The SPP therefore set out in late 2006 to use Teen Second Life® virtual world to support the development of the vision of schome, informed by current understandings about learning, pedagogy and the ‘tools’ available to us today.

This paper provides an overview of the first three phases of the SPP and briefly outlines the research methodologies used within it. This leads into a discussion of the potential of virtual worlds to support pedagogical exploration, which in turn leads to consideration of three dimensions of practice that emerged from the SPP. These three dimensions, which correspond closely with a framework developed in post‐compulsory education, are illustrated by use of descriptions of activities and other data from the SPP. The paper concludes by raising questions about the extent to which pedagogical practices will change in the future as a result of the opportunities offered by virtual worlds.
Life Stress and Major Depression
Authors: Monroe Scott M. , Reid Mark W.
Published: April 2009

People have long believed that adversity and stress contribute to emotional problems in general and to depression in particular. A considerable body of research has supported this intuition, documenting a consistent association between major stressful life events and the onset of clinical depression. However, most individuals under stress do not become depressed, sometimes depression develops without prior stress, and distinguishing psychological distress from major depression can be diagnostically challenging. In varying forms and degrees, life stress may play multiple roles in relation to major depression. In this article, we outline the opportunities and obstacles associated with conceptualizing depression from a life-stress perspective and discuss the implications for future research.
Multiple Systems in Decision Making
Authors: Frank Michael J. , Cohen Michael X. , Sanfey Alan G.
Published: April 2009

Various psychological models posit the existence of two systems that contribute to decision making. The first system is bottom-up, automatic, intuitive, emotional, and implicit, while the second system is top-down, controlled, deliberative, and explicit. It has become increasingly evident that this dichotomy is both too simplistic and too vague. Here we consider insights gained from a different approach, one that considers the multiple computational demands of the decision-making system in the context of neural mechanisms specialized to accomplish some of that system's more basic functions. The use of explicit computational models has led to (a) identification of core trade-offs imposed by a single-system solution to cognitive problems that are solved by having multiple neural systems, and (b) novel predictions that can be tested empirically and that serve to further refine the models.
Nightmares, Bad Dreams, and Emotion Dysregulation
Authors: Levin Ross , Nielsen Tore
Published: April 2009

Nightmares—vivid, emotionally dysphoric dreams—are quite common and are associated with a broad range of psychiatric conditions. However, the origin of such dreams remains largely unexplained, and there have been no attempts to reconcile repetitive traumatic nightmares with nontraumatic nightmares, dysphoric dreams that do not awaken the dreamer, or with more normative dreams. Based on recent research in cognitive neuroscience, sleep physiology, fear conditioning, and emotional-memory regulation, we propose a multilevel neurocognitive model that unites waking and sleeping as a conceptual framework for understanding a wide spectrum of disturbed dreaming. We propose that normal dreaming serves a fear-extinction function and that nightmares reflect failures in emotion regulation. We further suggest that nightmares occur as a result of two processes that we term affect load—a consequence of daily variations in emotional pressures—and affect distress—a disposition to experience events with high levels of negative emotional reactivity.
Executive Function
Authors: Banich Marie T.
Published: April 2009

In general, executive function can be thought of as the set of abilities required to effortfully guide behavior toward a goal, especially in nonroutine situations. Psychologists are interested in expanding the understanding of executive function because it is thought to be a key process in intelligent behavior, it is compromised in a variety of psychiatric and neurological disorders, it varies across the life span, and it affects performance in complicated environments, such as the cockpits of advanced aircraft. This article provides a brief introduction to the concept of executive function and discusses how it is assessed and the conditions under which it is compromised. A short overview of the diverse theoretical viewpoints regarding its psychological and biological underpinnings is also provided. The article concludes with a consideration of how a multilevel approach may provide a more integrated account of executive function than has been previously available.
Effects of Prenatal Social Stress on Offspring Development
Authors: Kaiser Sylvia , Sachser Norbert
Published: April 2009

In nonhuman mammals, the social environment in which pregnant females live is critical for their offsprings' brain development, endocrine state, and social and sexual behavior later in life. Social instability during pregnancy generally brings about a behavioral and neuroendocrine masculinization in daughters and a less pronounced expression of male-typical traits in sons. We favor the hypothesis that such behavioral effects of prenatal social stress are not necessarily “pathological” (nonadaptive) consequences of adverse social conditions. Rather, pregnant mothers could be adjusting their offspring to their environment in an adaptive way.
Can Countries with Severe Labor Market Frictions Gain from Globalization?
Authors: Grieben Wolf‐Heimo
Published: April 2009

The interaction between increased Southern trade integration (globalization) and labor market frictions is analyzed in a dynamic general‐equilibrium North–South nonscale growth model with endogenous Northern innovation and endogenous Southern imitation. The qualitative employment, growth, and relative‐wage effects of globalization are shown to depend crucially on the degree of Northern labor market frictions. I demonstrate that only Northern countries with particularly large labor market adjustment costs for both firms and workers benefit from globalization in terms of permanently lower unemployment, temporarily faster growth, and permanently higher wages. This is because of the resulting general‐equilibrium feedback effects of Northern labor market frictions that deter Southern imitation incentives. The result does not imply the recommendation to increase Northern labor market rigidities, but it challenges the common belief that labor market flexibility helps Northern countries to better adjust to the “globalization threat” coming from the South.
The Welfare Effects of Differential Tariff Rates
Authors: Ogawa Yoshitomo
Published: April 2009

This paper considers a two‐country, three‐good economy in which one country imposes tariffs on import goods at a uniform rate, while the other country engages in free trade. In such an economy, we examine the welfare effects of changing tariff rates toward differential tariffs from uniform tariffs.
An Inside Look at the Two Envelopes Paradox
Authors: Falk Ruma , Nickerson Raymond S.
Published: April 2009

When two sealed envelopes contain money, one twice as much as the other, a player should be indifferent between them. But when one envelope is opened, one's decision should vary as a function of the observed value and one's subjective probabilities.
Knowing Your Limitations
Authors: Foster Colin
Published: April 2009

This article reflects on whether probability statements can usefully be made about one‐off exceptional events.
Variance of a Few Observations
Authors: Joarder Anwar H.
Published: April 2009

This article demonstrates that the variance of three or four observations can be expressed in terms of the range and the first order differences of the observations. A more general result, which holds for any number of observations, is also stated.
Explanatory Power and Statistical Significance
Authors: Eisenhauer Joseph G.
Published: April 2009

Very little explanatory power is required in order for regressions to exhibit statistical significance. This article discusses some of the causes and implications.
The Colour of Money
Authors: Fletcher Mike
Published: April 2009

We consider how probability theory can be used to increase one's chances of winning in the new television game show The Colour of Money.
The Correlation between Two Random Variables in a Coin‐Tossing Experiment
Authors: Shiwalkar Jyoti P. , Deshpande M.N.
Published: April 2009

We find the correlation of two jointly distributed random variables connected with a coin tossing experiment. The marginal distributions are binomial and negative binomial.