bluuebunny/crossref_metadata_2025_split huggingface dataset:
Identifying under‐performing surgeons
Authors: Singh R. , Smeeton N. , O'Brien T.S. 
Published: May 2003

OBJECTIVETo estimate the likelihood of poor surgical results being explained by chance rather than under‐performance.METHODSThe 30‐day mortality rates after radical cystectomy for bladder cancer were analysed theoretically. Surgical competence was defined as a mortality rate of 4%, excellence as 2% and under‐performance as 8%, 12%, 20% or 40%. Four scenarios were explored for surgeons of different competence: first, the sample size required to show that a given level of under‐performance is very unlikely to be due to chance; second, the likelihood of two or more consecutive deaths in a series of cases; third, the likelihood of clustering of deaths, defined as two deaths in five or in 10 cases; and last, the likelihood of outstanding surgical results (i.e. no deaths) being achieved in small cohorts by surgeons of differing competence.RESULTSFor surgeons with a mortality rate of 8%, 12%, 20% or 40%, the sample sizes needed to prove under‐performance are 211, 65, 21 and seven, respectively. For consecutive deaths, 0.4% of excellent, 1.4% of competent and 21% of surgeons with a mortality rate of 12% will experience two or more consecutive deaths in the next 10 cases. For clustered deaths, 1% of excellent, 5% of competent and 23% of seriously under‐performing surgeons (mortality rates ≥ 12%) will experience two deaths in their next 10 cases. Lastly, for the likelihood of outstanding results, only 3.6% of surgeons with an 8% mortality rate and < 1% of surgeons with a mortality rate ≥ 12% will experience no deaths over 40 consecutive cases.CONCLUSIONSVery large cohorts are needed to confirm even significant under‐performance. Consecutive deaths are very unlikely events for competent surgeons. Clustered deaths (two deaths in 10 cases) are very unlikely events for excellent surgeons but plausible for competent ones. Analysis of consecutive/clustered deaths is limited by low statistical sensitivity; only up to a quarter of seriously under‐performing surgeons are identified. No deaths in 40 consecutive cases implies competence.
Urodynamics in a rat neurogenic bladder model with a unilateral electrolytic lesion of the basal forebrain
Authors: Shimizu I. , Kawashima K. , Ishii D. , Oka M. 
Published: May 2003

Despite the significant clinical problems of bladder dysfunction, specifically affecting the individual's quality of life, our understanding of this disease is limited. The main problem relates to the lack of clinically relevant models. The paper by Shimizu et al. describes the development of a neurogenic bladder model in the rat by an electrolytic unilateral lesion of the right basal forebrain. This model mimics the clinical situation of increased voiding frequency and decreased micturition threshold pressure. The group also uses this model to test the effects of AH‐9700, a potent sigma receptor‐agonist, with some success. The overall develop of clinically relevant models has important implications in future drug development and testing. OBJECTIVETo investigate the changes in bladder function in rats with an electrolytic lesion of the right basal forebrain (RBF) and to determine the effects of AH‐9700, a novel sigma receptor ligand, on cystometry in RBF‐lesioned rats.MATERIALS AND METHODSA lesion was made electrolytically in the RBF of male Wistar rats. At 7 or 8 days after the lesion or sham surgery, continuous cystometry was performed in awake rats. In addition, contractile responses to electrical field stimulation or carbachol were measured in isolated bladder strips, as were the forebrain contents of acetylcholine, monoamine neurotransmitters and their metabolites.RESULTSRBF‐lesioned rats showed a remarkable increase in voiding frequency, with a decrease in voiding threshold pressure but no change in voiding pressure, compared with sham‐operated rats. However, contractile responses in bladder strips isolated from RBF‐lesioned rats were no different from those in strips isolated from sham‐operated rats. In RBF‐lesioned rats, the contents of acetylcholine, dopamine, 4‐dihidroxyphenylacetic acid and homovanillic acid were significantly decreased in the right forebrain. AH‐9700 dose‐dependently decreased the voiding frequency and increased the threshold pressure in RBF‐lesioned rats. Anti‐muscarinic agents (oxybutynin and propiverine) also decreased the voiding frequency, but their effects were less potent than that of AH‐9700.CONCLUSIONSThe RBF‐lesioned rat may be a useful model for the neurogenic bladder of supraspinal origin. Moreover, AH‐9700 effectively improves bladder dysfunction in this model.
Contralateral adrenal metastasis of renal cell carcinoma: treatment, outcome and a review
Authors: Lau W.K. , Zincke H. , Lohse C.M. , Cheville J.C. , Weaver A.L. , Blute M.L. 
Published: May 2003

The group from the Mayo Clinic review their experience with contralateral adrenal metastasis in 11 patients, two with synchronous and nine with metachronous metastases, all being treated by adrenalectomy. Although nine of the 11 patients had died from RCC by the time of review, the authors felt that removal of contralateral adrenal metastasis had a beneficial effect; this sustains the belief that surgical removal of solitary metastases is advisable. Urologists from London address the concept of surgical variables as being of major importance. We will be hearing more about ‘under performing surgeons’, and I felt that an editorial comment from two European urologists would help to put the article in place for the reader. I can guarantee that further views are on their way about this important topic. Screening for prostate cancer has occupied many column inches in most urological Journals, and readers are of course aware of the randomized studies being conducted in North America, Europe and elsewhere. Authors from South Africa describe some of the problems associated with developing a screening programme in a less developed part of the world. They show that it can be extremely difficult to induce patients screened for the PSA to attend for their prostate biopsy. OBJECTIVETo report the surgical treatment of patients with renal cell carcinoma (RCC) metastatic to the contralateral adrenal gland and compare our experience with previous reports, as such metastases are found in 2.5% of patients with metastatic RCC at autopsy, and the role of resecting metastatic RCC at this site is not well defined.PATIENTS AND METHODSWe retrospectively identified 11 patients who had surgery for metastatic RCC to the contralateral adrenal gland between October 1978 and April 2001. The patients’ medical records were reviewed for clinical, surgical and pathological features, and the patients’ outcome.RESULTSThe mean (median, range) age of the patients at primary nephrectomy was 60.9 (64, 43–79) years; all had clear cell (conventional) RCC. Synchronous contralateral adrenal metastasis occurred in two patients. The mean (median, range) time to contralateral adrenal metastasis after primary nephrectomy for the remaining nine patients was 5.2 (6.1, 0.8–9.2) years. All patients were treated with adrenalectomy; there were no perioperative complications or mortality. Seven patients died from RCC at a mean (median, range) of 3.9 (3.7, 0.2–10) years after adrenalectomy for contralateral adrenal metastasis; one died from other causes at 3.4 years, one from an unknown cause at 1.7 years and two were still alive at the last follow‐up.CONCLUSIONSThe surgical resection of contralateral adrenal metastasis from RCC is safe; although most patients died from RCC, survival may be prolonged in individual patients. Hence, in the era of cytoreductive surgery, the removal of solitary contralateral adrenal metastasis seems to be indicated.
Catheter‐associated urinary tract infections: prevalence of uropathogens and pattern of antimicrobial resistance in a UK hospital (1996–2001)
Authors: Wazait H.D. , Patel H.R.H. , Veer V. , Kelsey M. , Van Der Meulen J.H.P. , Miller R.A. , Emberton M. 
Published: May 2003

OBJECTIVETo assess the change in the bacterial profile and pattern of antibiotic resistance of catheter‐associated urinary tract infections (CAUTIs, the most prevalent form of nosocomial infections) between 1996 and 2001.MATERIALS AND METHODSCatheter samples of urine (CSUs) submitted in 1996, 1998 and 2001 (2451, 2460 and 3349 specimens, respectively) were analysed. The distribution of different uropathogens in bacterial CAUTIs and their in vitro antimicrobial resistance was evaluated over the study interval. The likelihood ratio test was used to assess whether there was a linear trend according to calendar year.RESULTS Escherichia coli was the most frequently isolated pathogen in all years, but its frequency declined over time (35.6%, 32.5% and 26.6%, respectively). Enterococcus was the second most frequent overall, with a significant increase in frequency with time (11.8%, 15.3% and 22.0%, respectively). There was also a considerable change in resistance patterns to antibiotics. As a result, in 1996, CAUTIs were least often resistant to ciprofloxacin (8.0%) followed by co‐amoxiclav (18.5%) and cephalexin (25.4%). In 2001, CAUTIs were least often resistant to co‐amoxiclav (22.5%), followed by ciprofloxacin (27.2%) and nitrofurantoin (28.8%).CONCLUSIONThe types of organisms associated with CAUTI have changed over the last 5 years in a UK institution, as have the patterns of antibiotic resistance. Currently, the most appropriate agents for the empirical management of CAUTIs seem to be co‐amoxiclav, ciprofloxacin and nitrofurantoin.
The long‐term outcome of bilateral Cohen ureteric reimplantation under a common submucosal tunnel
Authors: Androulakakis P.A. , Stefanidis A.A. , Karamanolakis D.K. , Moutzouris V. , Koussidis G. 
Published: May 2003

OBJECTIVETo analyse the results of bilateral Cohen reimplantation under a common submucosal tunnel, over an 18‐year period.PATIENTS AND METHODSWe retrospectively examined 102 children (35 boys and 67 girls, median age 5.5 years, range 0.5–13.5) who underwent bilateral antireflux ureteric reimplantation from 1983 to 2000 with a modified Cohen technique, re‐implanting both ureters under a common submucosal tunnel in the mid‐trigonal area, to treat primary vesico‐ureteric reflux (VUR, 99 patients) or obstructive megaureter (three). The mean (range) follow‐up was 10.6 (2–18) years.RESULTSThe operation was successful in 198 of 204 (97%) ureters. One patient had vesico‐ureteric stenosis in one ureter and was re‐operated successfully. In two ureters in two different patients there was transient stasis after surgery caused by oedema within the tunnel, which gradually resolved. Two ureters in two other patients had reflux after surgery, which resolved spontaneously after 12 and 24 months, respectively. A 6‐month old baby had anuria after surgery because of acute compression of both ureters within a narrow tunnel; this patient was re‐operated, the tunnel widened and the obstruction resolved. None of 82 patients who had reached school age by the time of their last follow‐up showed signs of voiding dysfunction.CONCLUSIONSThe modified bilateral Cohen reimplantation with both ureters under a common submucosal tunnel offers very good long‐term results in curing VUR or obstructive megaureter. Crossing one ureter upon the other within the tunnel does not predispose to long‐term obstruction. From these results we recommend it as a reliable technique for surgically treating bilateral VUR or obstructive megaureter.
Laparoscopic renal biopsy: a 9‐year experience
Authors: Shetye K.R. , Kavoussi L.R. , Ramakumar S. , Fugita O.E. , Jarrett T.W. 
Published: May 2003

Renal biopsy is a frequent procedure in patients with suspected intrinsic renal disease. In some patients the blind percutaneous approach is contraindicated; the authors from Johns Hopkins describe their experience over a 9‐year period using a laparoscopic approach. They found that adequate tissue could be obtained for biopsy in the large majority of cases, and that complications occurred in a tiny minority. Most patients were discharged within 24 h. They indicate the advantages in removing tissue by this method. Authors from Varanasi, India describe how artificial neural networks were used in an attempt to predict optimum renal stone fragmentation in patients undergoing ESWL. They were encouraged by the findings in what was essentially a pilot study, and felt that with a larger data set, the value of their network system could be enhanced. OBJECTIVESTo present our experience and outcome of consecutive laparoscopic renal biopsy over a 9‐year period, as renal biopsy remains an important diagnostic procedure for evaluating proteinuria, haematuria and renal failure, but when percutaneous biopsy is contraindicated, a laparoscopic biopsy is an attractive option because it is minimally invasive.PATIENTS AND METHODSSeventy‐four patients (29 male, 45 female, mean age 45 years, range 3–79) had a laparoscopic renal biopsy taken for various indications, e.g. morbid obesity, solitary kidney, coagulopathy, failed percutaneous biopsy, high location of the kidney and poor visualization with ultrasonography. The kidney was approached via a laparoscopic retroperitoneal route using a two‐port technique, with the patient in the flank position. After identifying the kidney, one to five cortical biopsies were obtained with cup‐biopsy forceps.RESULTSAdequate tissue was obtained in 96% of the patients; the mean (range) operative duration was 123 (9–261) min and the estimated blood loss 67 (5–2000) mL. Forty‐three patients were discharged within 24 h. Complications occurred in 10 patients, with significant bleeding in three. One patient died after surgery, secondary to a perforated peptic ulcer while on high‐dose steroid therapy.CONCLUSIONLaparoscopic renal biopsy is a safe and effective alternative to open renal biopsy for patients in whom percutaneous biopsy is not feasible. It offers the advantage of obtaining cortical biopsies and achieving haemostasis under direct vision. Adequate renal tissue is obtained in most cases. Recovery and convalescence are short for most patients.
Urogynaecological and obstetric issues in women with the exstrophy‐epispadias complex
Authors: Mathews R.I. , Gan M. , Gearhart J.P. 
Published: May 2003

The authors from Copenhagen write about their 15‐year consistent strategy in the treatment of antenatally suspected PUJ obstruction. The group deals with this controversial subject in some detail, and they outline data which they feel are helpful for urologists giving advice to parents about the advisability of having the condition treated by operative or conservative means. The Cohen technique for the treatment of bilateral VUR, using a common submucosal tunnel, over an 18‐year period is described by authors from Athens; they found that the technique offers excellent long‐term results, and that crossing one ureter upon the other within the tunnel does not predispose to obstruction. OBJECTIVETo review of the sexual and urogynaecological issues faced by a large cohort of women with the exstrophy‐epispadias complex (EEC).PATIENTS AND METHODSThe study comprised 83 women and girls with EEC; a confidential survey was mailed to identify their social and sexual concerns. Fifty‐six women had classical bladder exstrophy (CBE), 13 had female epispadias (FE) and 14 had cloacal exstrophy (CE). Data on the initial method of reconstruction and urogynaecological problems were obtained from a review of the hospital records. Information on continence, infection and sexual function was obtained from 34 completed surveys.RESULTSThe bladder was closed in 51 patients with CBE and 13 with CE. Urinary calculi developed in 10 patients with CBE, two with FE and three with CE. Vaginal and uterine prolapse occurred an earlier age in patients with EEC. Eight women had 13 pregnancies, eight of which resulted in normal healthy children. Overall continence was achieved in 85% of the women surveyed. Urinary tract infections remained a frequent problem for women with EEC; only 27% of respondents indicated that they were infection‐free. Women aged> 18 years (24) who responded indicated that they had appropriate sexual desire; 16 were sexually active and the mean age for commencing sexual activity was 19.9 years. Six patients had dyspareunia and 10 indicated that they had orgasms. However, five additional patients indicated that they had restricted intercourse, as they were dissatisfied with the cosmesis of their external genitalia.CONCLUSIONSSexual and gynaecological issues become increasingly important in patients with EEC as they become adults. Understanding these issues faced by patients with EEC as they mature will permit better counselling of future patients.
Age of ovary determines remaining life expectancy in old ovariectomized mice
Authors: Cargill Shelley L. , Carey James R. , Müller Hans‐Georg , Anderson Gary 
Published: May 2003

SummaryWe investigated the capacity of young ovaries, transplanted into old ovariectomized CBA mice, to improve remaining life expectancy of the hosts. Donor females were sexually mature 2‐month‐olds; recipients were prepubertally ovariectomized at 3 weeks and received transplants at 5, 8 or 11 months of age. Relative to ovariectomized control females, life expectancy at 11 months was increased by 60% in 11‐month recipient females and by 40% relative to intact control females. Only 20% of the 11‐month transplant females died in the 300‐day period following ovarian transplantation, whereas nearly 65% of the ovariectomized control females died during this same period. The 11‐month‐old recipient females resumed oestrus and continued to cycle up to several months beyond the age of control female reproductive senescence. Across the three recipient age groups, transplantation of young ovaries increased life expectancy in proportion to the relative youth of the ovary. Our results relate to recent findings on the gonadal input upon aging in Caenorhabditis elegans and may suggest how the mammalian gonad, including that of humans, could regulate aging and determine longevity.
Sources of semiochemicals mediating host finding inCallosobruchus chinensis(Coleoptera: Bruchidae)
Authors: Babu A. , Hern A. , Dorn S. 
Published: May 2003

AbstractBruchid pests such asCallosobruchus chinensis(Linnaeus) endanger stored legume seeds throughout the tropical belt. The chemical composition of the headspace volatiles from healthy and fourth instar larvae-infested cowpea seeds were identified, characterized, and compared using gas chromatography–mass spectrometry. Y-tube olfactometer bioassays were performed to evaluate the effect of these chemicals on the orientation of conspecific adult females. Analysis of volatiles released from healthy and infested seeds revealed qualitative differences for three out of the 17 compounds identified. Dimethyl disulphide, isobutenyl methyl ketone and methyl trisulphide were found only in the blend emitted from infested but not from healthy seeds. Quantitative differences were apparent for tridecane which was released in larger amounts from infested seeds. While volatiles collected from healthy seeds were attractive to female bruchids, volatiles collected from infested seeds were repellent. To test the hypothesis that the qualitative differences in the chemical composition found may be due to insect-derived components, the volatiles from frass and fourth instar larvae combined were analysed. These volatiles contained both of the sulphides emitted from infested seed but not from healthy seeds. Although a limited induction of volatiles from cowpea seeds cannot be excluded, it is postulated that behavioural differences of the female weevils are largely due to insect-derived semiochemicals. The potential use of such semiochemicals as part of an integrated pest management strategy is discussed.
Diving beetles (Dytiscidae) as predators of mosquito larvae (Culicidae) in field experiments and in laboratory tests of prey preference
Authors: Lundkvist E. , Landin J. , Jackson M. , Svensson C. 
Published: May 2003

AbstractField experiments were performed in artificial ponds to evaluate how the density of predatory diving beetles (Dytiscidae) would affect the population levels of mosquito larvae (Culicidae). Mosquitoes colonizing the ponds were predominantly species of the genus Culex. In 2000, most of the dytiscids colonizing the ponds were small (Hydroporus spp.), and these predators had no impact on the size of larval mosquito populations, not even in ponds with added dytiscids. In 2001, larger beetles (Ilybius, Rhantus, and Agabus spp.) were more common, and there were significantly fewer mosquito larvae in ponds with the highest numbers of dytiscids. There was a negative correlation between numbers of diving beetles in the ponds and the mean body length of mosquito larvae. In neither year could dytiscid densities be maintained above a certain level owing to emigration. In laboratory tests, there were marked differences between three common dytiscid species in regard to preferences for Daphnia and Culex species as prey: Colymbetes paykulli Erichson chose mosquito larvae more often, whereas both Ilybius ater (De Geer) and I. fuliginosus (Fabricius) preferred Daphnia spp. All of the tested dytiscids consumed large numbers of prey. Since some dytiscid species can efficiently decrease populations of mosquito larvae, they are probably important in the natural control of these dipterans.
The valuation discount of multi‐segment firms in Australia
Authors: Fleming Grant , Oliver Barry , Skourakis Steven 
Published: May 2003

AbstractThis paper refines the Berger and Ofek (1995) methodology to estimate the valuation discount of multi‐segment firms in Australia between 1988 and 1998. Evidence is found that based on earnings before tax, the sample of multi‐segment firms traded at a 29 per cent greater discount than a comparable portfolio of single segment firms over the sample period. To explain the results further analysis shows that the valuation discount was driven by poorly performing multi‐segment firms rather than multi‐segment firms per se. This raises questions about studies that conclude that diversification is value destroying.
Capital gains tax and the capital asset pricing model
Authors: Lally Martin , Van Zijl Tony 
Published: May 2003

AbstractThis paper develops a version of the Capital Asset Pricing Model that views dividend imputation as affecting company tax and assumes differential taxation of capital gains and ordinary income. These taxation issues aside, the model otherwise rests on the standard assumptions including full segmentation of national capital markets. It also treats dividend policy as exogenously determined. Estimates of the cost of equity based on this model are then compared with estimates based on the version of the CAPM typically applied in Australia, which differs only in assuming equality of the tax rates on capital gains and ordinary income. The differences between the estimates can be material. In particular, with a high dividend yield, allowance for differential taxation can result in an increase of two to three percentage points in the estimated cost of equity. The overall result obtained here carries over to a dividend equilibrium, in which firms choose a dividend policy that is optimal relative to the assumed tax structure.