bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of Melt Chemistry on the Spectral Absorption Coefficient of Molten Aluminum Oxide
Authors: Weber J. K. Richard , Nordine Paul C. , Krishnan Shankar
Published: October 2005

Values of the spectral absorption coefficient (α) of liquid aluminum oxide were determined by transmission of a pulsed dye laser beam incident on continuous‐wave (CW) CO2‐laser‐melted pendant drops attached to sapphire filaments. Measurements were made on molten drops of Verneuil sapphire at wavelengths of 0.450 and 0.633 μm, at ambient oxygen partial pressures from 10‐10 to 1 bar in eight pure gases (Ar, CO, CO2, H2, H2O, HCI, N2 and O2), in CO/CO2 mixtures, and in H2/H2O mixtures, and at a temperature of ca. 2400 K. Specimens contaminated with iron, magnesium, silicon, and tungsten were also investigated in an oxygen atmosphere. At a wavelength of 0.633 μm, the value of α was greater than 50 cm‐1 under reducing or inert gas conditions. It decreased to a minimum at intermediate oxygen partial pressures of 5 × 10‐5 bar in CO/CO2 mixtures and 5 × 10‐3 bar in H2/H2O mixtures, and increased at larger oxygen partial pressures. The specimens were opaque (α > 55 cm‐1) in hydrogen, in HCI at pressures above 0.04 bar. Specimens contaminated with 5000‐10000 ppm of Fe, Mg, Si, or W were also opaque. At a wavelength of 0.45 μm the liquid aluminum oxide specimens were opaque in Ar and oxygen, and gave α= 46 cm‐1 in CO2. The dynamic response when the ambient gas was changed from CO2 to argon showed that the transmission maximum for = 0.45 μm was at p(O2) < 0.1 bar.
Rare‐Earth Barium Stannates: Synthesis, Characterization, and Potential Use as Substrates for YBa2Cu3O7‐δ Superconductor
Authors: Koshy Jacob , Kumar Krishnan Sudarsana , Kurian Jose , Yadava Yogendra P. , Damodaran Alaatoor D.
Published: October 2005

A new group of complex perovskites, REBa2SnO5.5 (where RE = Pr, Sm, Eu, and Gd) have been synthesized and sintered as single‐phase materials with high sintered density and stability by the solid‐state reaction method. The structure of REBa2SnO5.5 was studied by the X‐ray diffraction technique, and all of them were found to be isostructural and have a cubic perovskite structure. The dielectric constant and loss factor values of these materials are in a range suitable for substrate applications. The X‐ray diffraction and resistivity measurements have shown that there is no detectable reaction between YBa2Cu3O7‐δ and REBa2SnO5.5, even when the substances are mixed thoroughly and sintered at 950°C for 15 h. Thick films of YBa2Cu3O7‐δ fabricated on polycrystalline REBa2SnO5.5 substrates gave superconducting zero resistivity transition TC(0)= 92 K, indicating the suitability of these new materials as substrates for YBa2Cu3O7‐δ films.
Measurement of Rising R‐Curve Behavior in Toughened Silicon Nitride by Stable Crack Propagation in Bending
Authors: Nishida Toshihiko , Hanaki Yoshikazu , Nojima Taketoshi , Pezzotti Giuseppe
Published: October 2005

A simple procedure for measuring the R‐curve properties of ceramics by a stable fracture test in three‐point bending is described. As a typical case, data are displayed for a Si3N4 material toughened by the presence of acicular grains in situ grown during the sintering process. The fracture mechanics specimen was a single‐edge double‐notched beam (SEDNB), whose notch was sharpened to a radius of <10 μm in order to reduce the amount of elastic energy stored at its root prior to crack extension. Furthermore, a stabilizer, specially designed for the bending geometry, was used to control crack stability. During stable extension, the crack could be easily arrested at selected locations of the load‐displacement curve, the load quickly released, and the stable crack extension directly measured by the die‐penetration technique. The crack resistance, KR, of the material was calculated from the measured crack extent and the onset load value before unloading. This method enabled us to precisely monitor the critical load value at which the load‐displacement curve deviated from linear behavior, as well as crack extensions from a few tens of micrometers to about 1 mm. As an application of this method, the fracture resistance of a Si3N4 material with rising R‐curve behavior was measured and found to increase from about 5.5 to 9.0 MPaμm1/2 within a 0.8‐mm extension.
Probing of 1:2 Ordering in Ba(Ni1/3Nb2/3)O3 and Ba(Zn1/3Nb2/3)O3 Ceramics by XRD and Raman Spectroscopy
Authors: Kim Byung‐Kook , Hamaguchi Hiro‐o , Kim In‐Tae , Hong Kug Sun
Published: October 2005

The 1:2 ordering in Ba(Ni1/3Nb2/3)O ceramics sintered at 1350‐1500°C has been investigated by using XRD and Raman spectroscopy. Both of the techniques show that the degree of the 1:2 ordering decreases as the sintering temperature increases. However, XRD discerns the 1:2 ordering only for the samples sintered at 1350‐1400°C, whereas Raman spectroscopy discerns the 1:2 ordering for all the samples. Similar results have been obtained for Ba(Zn1/3Nb2/3)O3 ceramics, where only the temperature range is slightly different. It is demonstrated that Raman spectroscopy can be a useful tool for probing of the 1:2 ordering in the A(B'II1/3B”V2/3)O3‐type complex perovskite compounds.
Fabrication of SiC‐Whisker‐Reinforced MoSi2 Composites by Tape Casting
Authors: Shaw Leon , Abbaschian Reza
Published: October 2005

In this paper, we describe a procedure for the processing of SiC‐whisker‐reinforced MoSi2 composites via tape casting. Based on the characteristics of SiC whiskers and MoSi2 powder in aqueous and nonaqueous solvents, a slip formulation (solvent, dispersant, binder, etc.) has been developed. The formulation developed allows for a uniform distribution of SiC whiskers in the matrix, easy separation of the tapes from the polymeric carrier, convenient control of both tape thickness and orientation of SiC whiskers, and a low binder burnout temperature. The latter is important for the prevention of the oxidation of MoSi2 powder during the binder burnout in an oxidizing atmosphere.
Formation of PbZrO3 by Transformation of Cubic ZrO2 Solid Solution
Authors: Aoyama Tatsuji , Kurata Naoki , Hirota Ken , Yamaguchi Osamu
Published: October 2005

Metastable ZrO2 solid soutions containing up to 50 mol% PbO are formed at low temperatures from amorphous materials prepared by the hydrazine method: the tetragonal phase up to 30 mol% PbO and the cubic phase between 30 and 20 mol% PbO. The compound PbZrO3 is formed at 615° to 690°C by transformation of c‐ZrO2 solid solution.
Retracted: Repressive domain of unliganded human estrogen receptor α associates with Hsc70
Authors: Ogawa Satoko , Oishi Hajime , Mezaki Yoshihiro , Kouzu‐Fujita Madoka , Matsuyama Reiko , Nakagomi Madoka , Mori Eri , Murayama Emi , Nagasawa Hiromichi , Kitagawa Hirochika , Yanagisawa Junn , Yano Tetsu , Kato Shigeaki
Published: October 2005

Estrogen receptor (ER) is a hormone‐inducible transcription factor as a member of the nuclear receptor gene superfamily. Unliganded ER is transcriptionally silent and capable of DNA binding; however, it is unable to suppress the basal activity of the target gene promoters, unlike non‐steroid hormone receptors that associate with corepressors in the absence of their cognate ligands. To study the molecular basis of how unliganded human ERα is maintained silent in gene regulation upon the target gene promoters, we biochemically searched interactants for hERα, and identified heat shock protein 70 (Hsc70). Hsc70 appeared to associate with the N‐terminal hormone binding E domain, that also turned out a transcriptionally repressive domain. Competitive association of Hsc70 with a best known coactivator p300 was observed. Thus, these findings suggest that Hsc70 associates with unliganded hERα, and thereby deters hERα from recruiting transcriptional coregulators, presumably as a component of chaperone complexes.
Altered genotypic and phenotypic frequencies of aphid populations under enriched CO2 and O3 atmospheres
Authors: Mondor Edward B. , Tremblay Michelle N. , Awmack Caroline S. , Lindroth Richard L.
Published: October 2005

Environmental change is anticipated to negatively affect both plant and animal populations. As abiotic factors rapidly change habitat suitability, projections range from altered genetic diversity to wide‐spread species loss. Here, we assess the degree to which changes in atmospheric composition associated with environmental change will influence not only the abundance, but also the genotypic/phenotypic diversity, of herbivore populations. Using free‐air CO2 and O3 enrichment (FACE) technology, we assess numerical responses of pea aphids (Acyrthosiphon pisum) exhibiting a pink–green genetic polymorphism and an environmentally determined wing polyphenism on broad bean plants (Vicia faba) under enriched CO2 and/or O3 atmospheres, over multiple generations. We show that these two greenhouse gases alter not only aphid population sizes, but also genotypic and phenotypic frequencies. As the green genotype was positively influenced by elevated CO2 levels, but the pink genotype was not, genotypic frequencies (pink morph : green morph) ranged from 1 : 1 to 9 : 1. These two genotypes also displayed marked differences in phenotypic frequencies. The pink genotype exhibited higher levels of wing induction under all atmospheric treatments, however, this polyphenism was negatively influenced by elevated O3 levels. Resultantly, frequencies of winged phenotypes (pink morph : green morph) varied from 10 : 1 to 332 : 1. Thus, atmospheric conditions associated with environmental change may alter not just overall population sizes, but also genotypic and phenotypic frequencies of herbivore populations, thereby influencing community and ecosystem functioning.
Food preferences and the value of animal food for the carabid beetleAmara similata(Gyll.) (Col., Carabidae)
Authors: Fawki S. , Toft S.
Published: October 2005

Abstract: Several studies have shown that the mainly granivorous carabid beetles, e.g.Amaraspp., include animal food in their diet to a considerable extent. We therefore hypothesized that the performance of these beetles would be enhanced by dietary mixing including both seeds and animal food. In order to test this, we conducted laboratory feeding experiments with adults and larvae ofAmara similata. Both adults and larvae were subjected to different diet treatments including: seeds, houseflies, grasshoppers, earthworms, slugs and snails in pure and mixed diets. Larval survival, development time, pupal and teneral weights were used as indicators of food quality for the larvae. For the adult beetles, mass change was used as an indicator of food quality. We found seeds to be high‐quality food, while all pure animal diets were of low quality for both adults and larvae. Animal foods added to the seed diet had both positive and negative effects. A mixed diet of all foods enhanced the mass gain of adults compared with the seed diet, but reduced larval performance dramatically. Earthworms and grasshoppers added to seeds increased the pupal and teneral weights, while reduced larval survival. Thus,A. similatais omnivorous with a mainly granivorous feeding habit. It may gain benefits on some fitness parameters and incur costs on others from preying or scavenging on animal food. Therefore, the overall fitness consequences of a mixed seed‐animal diet are uncertain.
Course of C‐reactive protein during continuous peritoneal dialysis‐associated peritonitis
Authors: TROIDLE LAURA , KLIGER ALAN , GORBAN‐BRENNAN NANCY , FINKELSTEIN FREDRIC
Published: October 2005

Objective:  C‐reactive protein (CRP) levels increase during peritonitis. Little is known about the extent and duration of CRP elevation.

Patients and Methods:  Patients on continuous peritoneal dialysis (CPD) therapy had a baseline CRP value at the start of the study. CRP values were determined at 48 h, 2 weeks and 4 weeks after an episode of peritonitis developed in the 13 months after the study started.

Results:  The demographic values and comorbid diseases of the patients developing and not developing peritonitis were not significantly different. Patients who developed peritonitis had a mean ± SD CRP value of 15.0 ± 11.1 mg/L compared with 15.7 ± 9.9 mg/L in patients without peritonitis. The CRP value rose to 118.35 ± 96.86 mg/L at 48 h, and decreased to 34.5 ± 43.6 mg/L at 2 weeks and to 30.1 ± 39.7 mg/L at 4 weeks after the onset of peritonitis. All types of peritonitis were associated with a significant increase in CRP at 48 h. Nine patients had CRP elevations above baseline at 4 weeks; seven patients had active medical issues.

Conclusion:  CRP values become significantly elevated during peritonitis. Most patients have a decrease in the CRP values toward baseline values at 4 weeks following the onset of peritonitis while 20% of patients had continued elevations. The significance of the elevations is unclear. Given the associations of CRP with cardiovascular mortality in both uremic and non‐uremic patients and the association of peritonitis with mortality, the role of this inflammatory marker deserves further evaluation.
Randomized controlled trial of pulse intravenous cyclophosphamide versus mycophenolate mofetil in the induction therapy of proliferative lupus nephritis
Authors: ONG LOKE MENG , HOOI LAI SEONG , LIM TECK ONN , GOH BAK LEONG , AHMAD GHAZALI , GHAZALLI ROZINA , TEO SUE MEI , WONG HIN SENG , TAN SI YEN , SHAARIAH WAN , TAN CHWEE CHOON , MORAD ZAKI
Published: October 2005

Background:  The aim of the present study was to evaluate the efficacy of mycophenolate mofetil in the induction therapy of proliferative lupus nephritis.

Methods:  Forty‐four patients from eight centres with newly diagnosed lupus nephritis World Health Organization class III or IV were randomly assigned to either mycophenolate mofetil (MMF) 2 g/day for 6 months or intravenous cyclophosphamide (IVC) 0.75–1 g/m2 monthly for 6 months in addition to corticosteroids.

Results:  Remission occurred in 13 out of 25 patients (52%) in the IVC group and 11 out of 19 patients (58%) in the MMF group (P = 0.70). There were 12% in the IVC group and 26% in the MMF group that achieved complete remission (P = 0.22). Improvements in haemoglobin, the erythrocyte sedimentation rate, serum albumin, serum complement, proteinuria, urinary activity, renal function and the Systemic Lupus Erythematosus Disease Activity Index score were similar in both groups. Twenty‐four follow‐up renal biopsies at the end of therapy showed a significant reduction in the activity score in both groups. The chronicity index increased in both groups but was only significant in the IVC group. Adverse events were similar. Major infections occurred in three patients in each group. There was no difference in gastrointestinal side‐effects.

Conclusions:  MMF in combination with corticosteroids is an effective induction therapy for moderately severe proliferative lupus nephritis.
Losartan reduces the costs of diabetic end‐stage renal disease: An Asian perspective
Authors: SENG WONG KOK , HWANG SHANG‐JYH , HAN DONG CHEOL , TEONG CHUA CHIN , CHAN JULIANA , BURKE THOMAS A , CARIDES GEORGE W , CHOI YON JONG
Published: October 2005

Objective:  To evaluate losartan and conventional antihypertensive therapy (CT) compared with CT alone on the cost associated with end‐stage renal disease (ESRD) in Hong Kong, Japan, Korea, Malaysia, Singapore and Taiwan.

Methods:  Reduction of end‐points in non‐insulin‐dependent diabetes mellitus with the angiotensin II antagonist losartan (RENAAL) was a multinational, double‐blind, randomized, placebo‐controlled trial to evaluate the renal protective effects of losartan on a background of CT in patients with type 2 diabetes and nephropathy. The primary composite end‐point was a doubling of serum creatinine, ESRD or death. Data on the duration of ESRD for the Asian subgroup of patients enrolled in RENAAL were used to estimate the economic benefits of slowing the progression of nephropathy. The cost associated with ESRD was estimated by combining the number of days each patient experienced ESRD with the average daily cost of dialysis from the third‐party payer perspective in Hong Kong, Japan, Korea, Malaysia, Singapore and Taiwan. Total cost, converted to US dollars, was the sum of ESRD and losartan costs.

Results:  Losartan plus CT reduced the number of days with ESRD by 37.9 per patient over 3.5 years compared with CT alone. This reduction in ESRD days resulted in a decrease in the cost associated with ESRD, which ranges from $910 to $4346 per patient over 3.5 years across the six countries or regions. After accounting for the cost of losartan, the reduction in ESRD days resulted in net savings in each of the six countries or regions, ranging from $55 to $515 per patient.

Conclusion:  Treatment with losartan in patients with type 2 diabetic nephropathy not only reduced the incidence of ESRD among Asian patients, but resulted in direct medical cost savings in countries or regions representing Asia.
Cardiac troponin I and beta 2 microglobulin as risk factors for early‐onset atherosclerosis in patients on haemodialysis
Authors: ZUMRUTDAL AYSEGUL , SEZER SIREN , DEMIRCAN SENOL , SEYDAOGLU GULSAH , OZDEMIR F NURHAN , HABERAL MEHMET
Published: October 2005

Aim:  To investigate the associations of different risk factors with carotid artery intima‐media thickness (C‐IMT) in non‐diabetic haemodialysis (HD) patients who had no clinical evidence of atherosclerosis.

Methods:  Seventy‐two HD patients (43 men, 29 women; mean age: 34.5 ± 10.6 years; mean time on HD: 47.9 ± 40.0 months) and 40 age‐ and sex‐matched healthy controls (26 men, 14 women; mean age: 35.5 ± 7.1 years) participated in the study. The relationship between C‐IMT and haematocrit‐corrected erythrocyte sedimentation rate (Hct‐corrected ESR), beta 2 microglobulin (beta2M) and serum cardiac troponin I (cTnI) levels beyond C‐reactive protein (CRP), lipid profile and lipoprotein(a), fibrinogen, homocysteine and left ventricular hypertrophy (LVH) were examined.

Results:  Mean C‐IMT of the HD patients was significantly greater than that of the control subjects (0.59 ± 0.06 vs 0.53 ± 0.07 mm, P = 0.002). C‐IMT of patients was positively correlated with age (r = 0.33), body mass index (r = 0.40), Hct‐corrected ESR (r = 0.37), CRP (r = 0.34), beta2M (r = 0.34), cTnI (r = 0.26), triglyceride (r = 0.26) and fibrinogen (r = 0.28) levels (P < 0.05 for all). The mean C‐IMT was significantly greater in patients with LVH than it was in those without LVH (P = 0.004). In multivariate regression analysis, age (P = 0.02), beta2M (P = 0.001), log‐transformed CRP (P = 0.03) and LVH (P = 0.01) were independently related with C‐IMT.

Conclusion:  Besides well‐known cardiovascular (CV) risk factors, cTnI and beta2M were related with C‐IMT in that they may have important roles in early‐onset atherosclerosis in this high‐risk population.
Parathyroidectomy in the calcimimetic era
Authors: ELDER GRAHAME J
Published: October 2005

SUMMARY:  With the introduction of the calcimimetic cinacalcet HCl, some patients who would previously have undergone parathyroidectomy are likely to remain on medical therapy. Data is available on complication rates and some important outcome measures of parathyroidectomy, but the efficacy of calcimimetics to influence patient‐based endpoints such as cardiovascular mortality and renal osteodystrophy has not been established. Nevertheless, cinacalcet HCl has been demonstrated to improve levels of calcium, phosphate, the calcium phosphate product and parathyroid hormone (PTH). Based on available data, parathyroidectomy is proposed as the preferred treatment option when averaged levels of intact PTH (iPTH) exceed 85–95 pmol/L despite optimal therapy. When iPTH levels exceed 50 pmol/L, parathyroidectomy should be considered if levels of serum calcium, phosphate or the calcium phosphate product are above established target ranges or when patients with established osteoporosis have progressive loss of bone mineral density. Because the currently‐recommended biochemical targets are difficult to achieve and maintain for many patients on dialysis, parathyroidectomy rates are likely to increase if these management proposals are followed. This highlights the need for prospective studies with ‘hard’ endpoints, to establish evidence‐based roles for parathyroidectomy and calcimimetic therapy.
Renal tubular function in children with β‐thalassemia minor
Authors: KALMAN SÜLEYMAN , ATAY A AVNI , SAKALLIOḠLU ONUR , ÖZGÜRTAŞ TANER , GÖK FAYSAL , KURT ISMAIL , KÜREKÇI A EMIN , ÖZCAN OKAN , GÖKÇAY ERDAL
Published: October 2005

Background:  β‐thalassemia minor is a common heterozygous haemoglobinopathy that is characterized by both microcytosis and hypochromia. It requires no treatment. It has been postulated that low‐grade haemolysis, tubular iron deposition and toxins derived from erythrocytes might cause renal tubular damage in adult patients with β‐thalassemia minor. Our aim was to investigate the renal tubular functions in children with β‐thalassemia minor and to determine its possible harmful effects.

Methods:  The study was conducted on 32 children (14 female and 18 male) at the age of 5.8 ± 3.1 years (range 2–14 years) with β‐thalassemia minor. The patients were classified as anaemic (haemoglobin (Hb) ≤ 11 g/dL) (Group 1, n = 14) and non‐anaemic (Hb > 11 g/dL) (Group 2, n = 18). A control group was formed with 18 healthy children whose ages and sexes match those in other groups (Group 3, n = 18). Fractional excretion of sodium (FENa, %), fractional excretion of magnesium (FEMg, %), fractional excretion of uric acid (FEUA, %) and tubular phosphorus reabsorption (TPR,%) were calculated with standard formulas. Urinary calcium excretion (mg/kg per 24 h), zinc (Zn) (µg/dL), glucosuria (mg/dL), β‐2 microglobulin (mg/dL) and N‐acetyl‐β–D‐glycosaminidase (NAG, U/mmol creatinine) levels were measured through biochemical methods.

Results:  There was no statistically significant difference among the three groups in terms of the results of FENa (%), FEMg (%), FEUA (%), TPR (%), calciuria (mg/kg per 24 h), NAG, urine Zn, proteinuria, glucosuria or urine β‐ 2 microglobulin levels (P > 0.05).

Conclusion:  On the contrary of children with β‐thalassemia major, renal tubular dysfunction has not been determined in children with β‐thalassemia minor in the present study.
Zoledronic acid is effective in preventing and delaying skeletal events in patients with bone metastases secondary to genitourinary cancers
Authors: Saad Fred , Lipton Allan
Published: October 2005

Patients with metastatic bone disease often have severe bone pain and debilitating skeletal complications. Zoledronic acid is the only bisphosphonate shown to be safe and effective in reducing skeletal‐related events (SREs), including pathological fractures, spinal cord compression, and radiation or surgery to bone in patients with bone metastases from advanced prostate cancer or renal cell carcinoma (RCC). In both tumour types, zoledronic acid significantly decreased the overall risk of developing an SRE, delayed their onset and significantly reduced the incidence of SREs compared with placebo. In patients with RCC, zoledronic acid also significantly delayed the time to progression of bone lesions by 5 months compared with placebo. Zoledronic acid is safe and well tolerated with long‐term use.
Growth of bone marrow stromal cells on small intestinal submucosa: an alternative cell source for tissue engineered bladder
Authors: Zhang Yuanyuan , Lin Hsueh‐Kung , Frimberger Dominic , Epstein Robert B. , Kropp Bradley P.
Published: October 2005

OBJECTIVE

To assess the potential use of bone marrow stromal cell (BMSC)‐seeded biodegradable scaffold for bladder regeneration in a canine model, by characterizing BMSCs and comparing them to bladder smooth muscle cells (SMCs) by immunohistochemistry, growth capability, and contractility.

MATERIALS AND METHODS

Bone marrow was taken by direct needle aspiration from the femurs of five beagle dogs for the in vitro study. Mononuclear cells were isolated by Ficoll‐Paque® density gradient centrifugation and cultivated in medium 199 with 10% fetal bovine serum. BMSCs were characterized by cell proliferation, in vitro contractility, immunohistochemical analysis, and the growth pattern on small intestinal submucosa (SIS) scaffolds compared to bladder SMC cultures from the same dogs. Another six dogs had a hemicystectomy and bladder augmentation with BMSC‐seeded (two), bladder cells including urothelial cells plus SMC‐seeded SIS (two) and unseeded SIS scaffolds (two). The six dogs were followed for 10 weeks after augmentation.

RESULTS

In vitro BMSCs had a significant contractile response to calcium‐ionophore, with a mean (sem) 36 (2)%, relative contraction (P < 0.01), which was similar to bladder SMCs but markedly different from fibroblasts. BMSCs also expressed α‐smooth muscle actin by immunohistochemical staining and Western blotting, but did not express desmin or myosin. In vivo, both BMSC‐seeded and bladder cell‐seeded SIS grafts had solid smooth‐muscle bundle formation throughout the graft.

CONCLUSIONS

BMSCs had a similar cell proliferation, histological appearance and contractile phenotype as primary cultured bladder SMCs. SIS supported three‐dimensional growth of BMSCs in vitro, and BMSC‐seeded SIS scaffold promoted bladder regeneration in a canine model. BMSCs may serve as an alternative cell source in urological tissue engineering.
The potassium sensitivity test: a predictor of treatment response in interstitial cystitis
Authors: Gupta Suresh K. , Pidcock Lol , Parr Nigel J.
Published: October 2005

OBJECTIVE

To determine whether the potassium sensitivity test (PST) can be used to predict the response to treatment with intravesical sodium hyaluronate in patients with interstitial cystitis.

PATIENTS AND METHODS

Thirty‐eight patients diagnosed with interstitial cystitis were recruited; each had a PST, carried out in a double‐blind fashion, followed by six weekly doses of intravesical sodium hyaluronate. The patients were assessed before and after treatment using a self‐administered interstitial cystitis symptom index (CSI) and problem index (PI). The clinical response was defined as none (<25% improvement in clinical symptoms), mild (>25%), moderate (50–75%) and excellent (>75%).

RESULTS

The PST was positive in 23 and negative or indeterminate in 13 patients; two patients withdrew from the study. Overall 20 of 36 (55%) patients reported an improvement after six doses of intravesical sodium hyaluronate, but 17 (74%) with a positive PST improved, compared to only five (22%) with a negative test (P = 0.03). There was an improvement in the CSI after treatment in both groups, but a significant improvement in the PI only in patients with a positive PST (P = 0.01). The magnitude of change for the CSI and PI was significantly greater in the positive than in the negative group (CSI, P = 0.043; PI, P < 0.001). There were no major complications. Three patients complained of pain after the test, and two with a positive and one with a negative PST developed a urinary tract infection.

CONCLUSIONS

Although the role of the PST in the diagnosis of interstitial cystitis requires further clarification, the test helps to predict the response to treatment with glycosaminoglycan‐substitution therapy.
Plasma levels of endothelin‐1, angiotensin II, nitric oxide and prostaglandin E2 in the venous and cavernosal blood of patients with erectile dysfunction
Authors: El Melegy Nagla Taha , Ali Mohamed‐Esam M. , Awad Efat M.A.
Published: October 2005

OBJECTIVES

To determine the alterations in the plasma levels of endothelin‐1, angiotensin II, nitric oxide (NO) and prostaglandin E2 (PGE2) in the venous and cavernosal blood of patients with organic and psychogenic erectile dysfunction (ED).

PATIENTS, SUBJECTS AND METHODS

The study included 32 patients complaining of ED; they were subdivided into two equal groups with either organic or psychogenic ED. Fifteen healthy potent age‐matched male volunteers were enrolled as a control group. For each patient, venous and cavernosal blood samples were obtained, while venous blood was obtained from the controls.

RESULTS

There were significantly greater mean plasma levels of endothelin‐1 and angiotensin II, and significantly lower mean plasma levels of NO and PGE2, in the venous blood of patients with ED than in the controls. Patients with organic ED had significantly higher levels of endothelin‐1 and significantly lower levels of NO in both venous and cavernosal blood than had those with psychogenic ED. There were significant positive correlations in both venous and cavernosal blood between endothelin‐1 and angiotensin II, and between NO and PGE2 in all patients with ED and the two subgroups. There were significant negative correlations between venous and cavernosal endothelin‐1 and NO, endothelin‐1 and PGE2, angiotensin II and NO, and between angiotensin II and PGE2.

CONCLUSION

The present results suggest that endothelin‐1 could be a clinical marker of diffuse endothelial disease manifested by ED. As angiotensin‐converting enzyme (ACE) activity controls angiotensin II there might be a rationale for the use of ACE inhibitors to prevent or treat ED. NO and PGE2 may provide new strategies for the pharmacological treatment of ED.
A retrospective study of the time to clinical endpoints for advanced prostate cancer
Authors: Sharifi Nima , Dahut William L. , Steinberg Seth M. , Figg William D. , Tarassoff Christopher , Arlen Philip , Gulley James L.
Published: October 2005

Authors from the National Cancer Institute present a study which assessed the time to androgen independence and overall survival for patients with metastatic prostate cancer. They reported a longer than expected survival with androgen‐independent prostate cancer, and make original observations on the time to metastatic disease for patients with no evidence of radiographic disease.

The new wave of chemotherapeutic agents for hormone‐resistant prostate cancer has generated a new interest in producing more. Dr Cora Sternberg from Rome presents information on satraplatin, a third‐generation orally available platinum analogue that shares more structural similarities with cisplatin. There are several other papers in this section on prostate bladder and renal cancer, and finally a paper from London on penile cancer, asking what surgical resection margins are required to achieve oncological control, and finding that the traditional 2 cm margin may be unnecessary, with excision margins of only a few millimetres needed to give excellent control.

OBJECTIVE

To determine the natural history of patients with prostate cancer who start initial androgen‐deprivation therapy (ADT) for biochemical failure with no radiographic evidence of disease (D0) or with radiographic metastatic disease (D2), as the history is either not well‐defined or is changing, and such data are critical for guiding therapy after prostate cancer recurrence.

PATIENTS AND METHODS

We retrospectively assessed the time to androgen‐independence (AI), defined as the first sustained rise in prostate‐specific antigen (PSA) level on ADT, time to metastatic disease and overall survival for 80 patients with metastatic prostate cancer in clinical trials at the National Cancer Institute.

RESULTS

ADT was initiated after metastatic disease in 37 patients and before metastatic disease in 43 patients; in these 43 patients, the median time to developing metastatic disease on ADT was 37.8 months. The median time to AI from the initiation of ADT was 19.3 and 13.1 months in D0 and D2 patients, respectively. The median overall survival from the start of ADT was 89.0 and 63.0 months, and the median overall survival from the time of AI was 63.1 and 44.2 months in D0 and D2 patients, respectively. These 80 patients, which included 43 who had no metastatic disease when starting ADT, had a median survival of 54.8 months after AI prostate cancer.

CONCLUSIONS

We describe the natural history of AI prostate cancer in D0 patients who eventually developed metastasis, and in D2 patients. The results suggest a longer than expected survival with AI prostate cancer, and to our knowledge this is the first study to report the time to metastatic disease for D0 patients from ADT and from AI. These results can be used to help design clinical trials in patients with D0 prostate cancer.
Clinical staging of prostate cancer: a computer‐simulated study of transperineal prostate biopsy
Authors: Crawford E. David , Wilson Shandra S. , Torkko Kathleen C. , Hirano Daisaku , Stewart J. Scott , Brammell Craig , Wilson R. Storey , Kawata Nozomu , Sullivan Holly , Lucia M. Scott , Werahera Priya N.
Published: October 2005

OBJECTIVE

To identify the precise location of prostate cancer within the gland and thus possibly permit more aggressive therapy of the lesion, while potentially sparing the noncancerous gland from ablative therapy.

MATERIALS AND METHODS

Three‐dimensional ‘solid’ computer models were reconstructed for 86 autopsy specimens and 20 stage T1c radical prostatectomy specimens. Transperineal biopsies were simulated for grid sizes of 5‐mm (method A) and 10‐mm (method B) with an 18 G, 23‐mm long biopsy needle. One or two biopsies per grid point were obtained for a total of 12–108 biopsies, depending on the size of the prostate. Clinically threatening cancers were defined as having volumes of ≥ 0.5 mL or Gleason sum ≥ 7.

RESULTS

Method A detected significantly more carcinomas than method B in both the autopsy and prostatectomy specimens (autopsy, 72 vs 51; prostatectomy, 50 vs 32, both P < 0.001). Method A also detected more clinically threatening cancers found at autopsy (38/40 vs 31/40, P = 0.008). Among autopsy patients with negative sextant biopsies whose disease was localized to one side, method A detected 72% and method B detected 29–43% (P < 0.001).

CONCLUSIONS

The results of this computer simulation show that 5‐ and 10‐mm grid biopsies detect three‐quarters and a third, respectively, at autopsy, of patients with the disease localized to one side of the prostate, which may be useful when planning highly selective ablative treatments in the future.
Nephron‐sparing surgery for renal tumours using selective renal parenchymal clamping
Authors: Denardi Fernandes , Borges Gustavo M. , Silva Walter , Stopiglia Rafael M. , Ferreira Ubirajara , Billis Athanase , Netto Nelson R.
Published: October 2005

OBJECTIVE

To describe a technical modification that facilitates nephron‐sparing surgery (NSS) for renal tumours, without clamping the renal pedicle or promoting renal surface hypothermia.

PATIENTS AND METHODS

Seventeen patients with renal tumours had NSS using the selective renal‐parenchymal clamping technique. In 11 patients the tumour was polar and in six it was central. The mean (range) size of the tumours was 3.6  (2–6) cm. The technique was performed using one or two large Satinsky vascular clamps. Time was not limited as there was no clamping of the renal pedicle, or renal hypothermia.

RESULTS

The mean (range) operative duration was 190 (120–300) min. Only one patient needed a blood transfusion. There were no complications in 13 patients after NSS. The mean (range) hospital stay was 5 (3–12) days. The pathological examination detected malignant tumours in 13 patients, and a microscopic examination showed adequate surgical margins in all. The mean (range) follow‐up was 24.5 (4–60) months. No patients required haemodialysis immediately after surgery or later.

CONCLUSIONS

Selective renal parenchymal clamping is a simple and efficient technical manoeuvre that facilitates NSS without dissection or clamping of the renal pedicle. Time is not limited as the ischaemia is limited to the tissue surrounding the tumour. The operative duration and blood loss are acceptable and the complications similar to those with the conventional technique. The size and position of the tumour could be limiting factors to this technique.
Estimating a frequency unseen: an application to ornithology
Authors: Albers C. J. , De Roos G. Th. , Schaafsma W.
Published: October 2005

The second author is involved in a capture–mark–recapture study of some wader species. Part of his program deals with resight observations. On a particular day he visually inspects a fairly stable population to identify the ringed birds by reading their ring‐number. Some ringed birds will be missed, so observations are repeated on other days. The issue of main interest is whether, after some repetitions, we can be sufficiently sure that all the ringed birds in the population have been identified or, equivalently, that the frequency of unseen birds is zero.

Most current theory is concerned with an asymptotic setting. In our ‘exact’ context the emphasis is on the determination of the ‘probability’ that the frequency of unseen birds is zero. This issue is settled by considering the more general problem of ‘estimating’ the frequency of the unseen birds by providing a predictive inference in the form of a probability distribution. We develop methods of inference based on the assumption of a bird‐independent probability pi of identifying a ringed bird on day i, as well as without this assumption. In Section 5 we critically examine these approaches.
On a 2 × 2 factorial design where the use of randomized response is one of the factors
Authors: van den Hout Ardo , Lensvelt‐Mulders Gerty J. L. M.
Published: October 2005

This paper discusses a survey where some respondents were asked sensitive questions directly and others were asked the same questions using randomized response. The use of randomized response was a factor in a 2 × 2 factorial design and dice were used to perform the randomization. First, the paper shows that the perturbation due to the dice can be described using the concept of misclassification and known conditional misclassification probabilities. Second, the paper formulates the likelihood for loglinear models and shows that latent class software can be used to analyse the data. An example including a power analysis is discussed.
Exponential rates for kernel density estimation under association
Authors: Henriques Carla , Oliveira Paulo Eduardo
Published: October 2005

The estimation of density based on positive dependent samples has been studied recently with consistency and asymptotic normality results being obtained. In with regard to the characterization on decrease rates the results have been scarce. We prove two versions of an exponential inequality: one assuming stationarity and association alone and the other under a further assumption on the joint distributions of the sample. These inequalities are then used to prove exponential decrease rates for the kernel estimator of the density with a uniform version over compact sets. The conditions assumed impose convenient decrease rates on the covariance structure of the sample. Some examples supposing geometrical or polynomial decrease rates on the covariances that fulfill our assumptions are presented in the last section. Explicit almost sure rates are derived for geometrically decreasing covariances. Under the extra assumption on the joint distributions the rates are close to the best known ones for independent variables.
Three Year Outcome of Cardiac Resynchronization Therapy: A Single Center Evaluation
Authors: STÅHLBERG MARCUS , BRAUNSCHWEIG FRIEDER , GADLER FREDRIK , KARLSSON HELENA , LINDE CECILIA
Published: October 2005

Aims: To evaluate the long‐term clinical outcome and device performance of cardiac resynchronization therapy in a consecutive sample of patients with moderate to severe heart failure.

Methods and Results: Between 1998 and 2000, forty consecutive patients with drug‐refractory heart failure due to ischemic or idiopathic dilated cardiomyopathy were selected for cardiac resynchronization therapy (CRT). After successful implantation of the coronary sinus lead (n = 35, 88%), patients were followed every sixth month by New York Heart Association (NYHA) functional class, the 6‐minute walking test (6´ walk), quality of life (QoL, Minnesota), and pacemaker control. NYHA‐class and 6´ walk were significantly improved after 6 months and continued to improve gradually until 36 months of follow‐up. The QoL improvement at 6 months was sustained over 3 years. After 3 years, the β‐blocker dose could be increased in 10/23 patients as compared to baseline. Nine patients had to be re‐operated. Coronary sinus lead thresholds were stable over time.

Conclusion: The clinical improvements by CRT are sustained over 3 years of follow‐up. In the setting of a University Medical Center, CRT can be applied in clinical routine with excellent clinical outcome, acceptable implantation success, and stable device performance over time.
Recurrence of Atrial Tachyarrhythmias in Implantable Cardioverter‐Defibrillator Recipients
Authors: DARBAR DAWOOD , WARMAN EDUARDO N. , HAMMILL STEPHEN C. , FRIEDMAN PAUL A. ,   for the Worldwide Jewel AF Investigators
Published: October 2005

Background:
Because the natural history of atrial tachyarrhythmia (AT) is not known in patients with implantable cardioverter‐defibrillators (ICDs) but without device‐based atrial therapies, we aimed to describe the characteristics and recurrence of AT in such patients.

Methods:
In this multicenter trial, 269 patients with standard indications for ICD placement and 2 episodes of AT in the preceding year received a dual‐chamber ICD capable of logging AT. Patients were randomly assigned to 3‐month periods of atrial therapies “on” or “off.” This analysis considered only the 118 patients with atrial therapies programmed off at ICD placement.

Results:
Fifty‐eight patients (49%) had at least 1 AT episode longer than 1 minute, and 21 (18%) had at least 1 prolonged episode (>24 hours). The median episode frequency for each patient (episodes per month) was 1.8 episodes longer than 1 minute, 0.8 longer than 1 hour, and 0 longer than 24 hours. The median AT burden was 12.2 hours per month.

Conclusions:
Patients with standard ICD indications and history of AT have infrequent episodes, frequent short episodes, or prolonged episodes of AT‐atrial fibrillation. However, the clinical characteristics examined did not distinguish among the groups. Improved diagnostic tools may help identify patients at risk for development of AT, thereby allowing specific therapies to be targeted to each group of patients.
Anatomic and Electrophysiologic Evaluation of a Right Lateral Atrioventricular Mahaim Fiber
Authors: MORITA NORISHIGE , KOBAYASHI YOSHINORI , KATOH TAKAO , TAKANO TERUO
Published: October 2005

We report a patient who underwent an electrophysiologic study and radiofrequency catheter ablation for a right lateral Mahaim fiber. During sinus rhythm with overt preexcitation, propagation mapping was performed in the right ventricle using a three‐dimensional electro‐anatomical mapping system (CARTO). Small discrete potentials, which reflected the excitation of the Mahaim fiber, could be recorded along the line from the vicinity of the parental tricuspid annulus to approximately one‐third of distal site from the base to the apex. The relationship of the timing of its potential to the anatomical location could be disclosed on recordings of the local electrogram and anatomical map.
Magnetic Resonance Angiography of Pulmonary Veins: Implications for Catheter Ablation of Atrial Fibrillation
Authors: MLČOCHOVÁ HANKA , TINTĚRA JAROSLAV , POROD VÁCLAV , PEICHL PETR , ČIHÁK ROBERT , KAUTZNER JOSEF
Published: October 2005

Introduction:
Catheter ablation of atrial fibrillation (AF) requires exact anatomical information about pulmonary venous (PV) ostia. In this study, anatomy of pulmonary veins (PVs) was assessed using three‐dimensional (3D) reconstructions of magnetic resonance angiography (MRA).

Methods and Results:
Contrast‐enhanced MRA of the PVs was performed in 40 patients (mean age 53 ± 9 years) with paroxysmal (30 patients) or persistent (10 patients) AF, scheduled for circumferential ablation around PV ostia. PV ostial anatomy and diameters were evaluated from multiplanar reconstructions and compared with 3D reconstructions. Thirty (75%) patients presented with a common left‐sided antrum (21 short and 9 long trunk), while additional PVs were found on right side in 23%. PV ostia were oblong in shape (mean diameters 17.0 ± 4.3 vs 10.5 ± 2.5 mm by two‐dimensional (2D) measurements, and 20.8 ± 7.6 mm vs 12.9 ± 3.3 mm by 3D reconstruction, in long and short axis, respectively). There was a correlation between measurements obtained from 2D and 3D images, although 3D imaging provided slightly larger diameters.

Conclusions:
MRA with 3D reconstructions is an important technique for preprocedural assessment of PVs that allows full understanding of their anatomy and size. This information may be important for selection of appropriate tools.
Electrophysiologic Characteristics of Atria in Patients Without Heart Disease
Authors: BREMBILLA‐PERROT BÉATRICE , BEURRIER DANIEL , HOURIEZ PIERRE , SUTY‐SELTON CHRISTINE , NIPPERT MARC , CLAUDON OLIVIER , ANDRONACHE MARIUS , ERNST YVES , KHALDI EMAD , BELHAKEM HADJ , POPOVIC BATRIC , DE LA CHAISE ARNAUD TERRIER , LOUIS PIERRE
Published: October 2005

Background: The significance of atrial fibrillation or tachycardia (AF) induction remains debatable. Some believe that the presence of heart disease (HD) increases the sensitivity and decreases the specificity of programmed atrial stimulation (PAS). There are few data in patients without HD. The purpose of the study was to evaluate the results of PAS in asymptomatic patients without HD and in those with documented spontaneous AF, but without HD, to know the diagnosis value of the technique.

Methods: A total of 4,900 PAS were consecutively performed. The control group (I, N=67) was defined by the absence of preexcitation syndrome, dizziness/syncope, hypertension, history of tachycardia, or other documented HD together with a normal 2D echocardiogram and 24‐hour Holter monitoring. They were compared to a group (II) of 54 patients with documented paroxysmal AF and without HD. PAS used one and two extrastimuli, delivered during sinus rhythm and two drive rates (600, 400 ms). Atrial‐effective refractory periods (ARP), their adaptation to cycle length, and conduction times were noted. AF induction was defined as the induction of AF lasting more than 1 minute.

Results: Group I patients (1.4% of 4,900) were younger than group II (51 ± 17 vs 65 ± 11 years, P < 0.001). A single extrastimulus never induced sustained AF in group I, but did so in 11 group II patients (20%); sustained AF was induced by two extrastimuli in 15 group I patients (22%) and in 31 group II patients (57%) (P < 0.001). There were no ARP and conduction time differences in group I patients with and without inducible AF, but there was a longer sinus cycle length in patients with inducible AF (977 ± 164 vs 838 ± 141 ms, P < 0.02). There were no electrophysiological differences in group II patients with and without inducible AF. No group I patient developed spontaneous AF (follow‐up 4 ± 2 years). The sensitivity of PAS with one extrastimulus was 20% and the specificity 100%; the sensitivity of PAS with two extrastimuli was 57% and the specificity 78%.

Conclusion: Sustained AF was not induced by one extrastimulus in control patients without symptoms, nor heart disease, but sustained AF was induced by two extrastimuli in 22% of these patients. The induction of a sustained AF by two extrastimuli should be interpreted cautiously, particularly in patients with a relative sinus bradycardia. However, the sensitivity of PAS with one extrastimulus was very low and two extrastimuli were required in patients with spontaneous AF to induce the tachycardia. Other electrophysiological parameters were not useful to differentiate patients with and without inducible AF.