Measuring and predicting the diffraction properties of cylindrically bent potassium acid phthalate, KAP(001), crystals.

This report presents the results from measuring the X-ray diffraction properties of a curved potassium acid phthalate (KAP(001)) spectrometer crystal using two measurement methods. One method used a diode type X-ray source and a dual goniometer analysis system, utilizing a flat, perfect KAP(001) crystal as the monochromator. The second method used a synchrotron source and dual crystal Si(111) monochromator. Bent crystals are used in X-ray spectrometers as dispersion elements. These crystals are bent into a circular cylinder section, and this bending can alter the rocking curve properties. The crystal rocking curves were measured for spectral energies ranging from 1250 to 4500 eV. A multi-lamellar model was compared to the measurements and showed good quantitative agreement. This provides a valuable tool for predicting the changes to the KAP (001) for any radius of curvature when the crystal is bent into a cylindrical section.

A technique for measuring the quality of an elliptically bent pentaerythritol [PET(002)] crystal.

We present a technique for determining the X-ray spectral quality from each region of an elliptically curved PET(002) crystal. The investigative technique utilizes the shape of the crystal rocking curve which changes significantly as the radius of curvature changes. This unique quality information enables the spectroscopist to verify where in the spectral range that the spectrometer performance is satisfactory and where there are regions that would show spectral distortion. A collection of rocking curve measurements for elliptically curved PET(002) has been built up in our X-ray laboratory. The multi-lamellar model from the XOP software has been used as a guide and corrections were applied to the model based upon measurements. But, the measurement of RI at small radius of curvature shows an anomalous behavior; the multi-lamellar model fails to show this behavior. The effect of this anomalous RI behavior on an X-ray spectrometer calibration is calculated. It is compared to the multi-lamellar model calculation which is completely inadequate for predicting RI for this range of curvature and spectral energies.

Measuring the diffraction properties of an imaging quartz(211) crystal.

A dual goniometer X-ray system was used to measure the reflectivity curve for a spherically bent quartz(211) crystal. An analysis of the dual goniometer instrument response function for the rocking curve width measurement was developed and tested against the actual measurements. The rocking curve was measured at 4510.8 eV using the Ti Kα1 characteristic spectral line. The crystal is the dispersion element for a high resolution spectrometer used for plasma studies. It was expected to have a very narrow rocking curve width. The analysis showed that we could measure the upper bound for the rocking curve width of the Qz(211) crystal. The upper bound was 58 µrad giving a lower bound for the instrument resolving power E/ΔE = 34 000. Greatly improved insight into the dual goniometer operation and its limitations was achieved.

Measuring the x-ray resolving power of bent potassium acid phthalate diffraction crystals.

This report presents the results from measuring the X-ray resolving power of a curved potassium acid phthalate (KAP(001)) spectrometer crystal using two independent methods. It is part of a continuing effort to measure the fundamental diffraction properties of bent crystals that are used to study various characteristics of high temperature plasmas. Bent crystals like KAP(001) do not usually have the same diffraction properties as corresponding flat crystals. Models that do exist to calculate the effect of bending the crystal on the diffraction properties have simplifying assumptions and their accuracy limits have not been adequately determined. The type of crystals that we measured is being used in a spectrometer on the Z machine at Sandia National Laboratories in Albuquerque, New Mexico. The first technique for measuring the crystal resolving power measures the X-ray spectral line width of the characteristic lines from several metal anodes. The second method uses a diode X-ray source and a double crystal diffractometer arrangement to measure the reflectivity curve of the KAP(001) crystal. The width of that curve is inversely proportional to the crystal resolving power. The measurement results are analyzed and discussed.

Integrated x-ray reflectivity measurements of elliptically curved pentaerythritol crystals.

The elliptically curved pentaerythritol (PET) crystals used in the Supersnout 2 x-ray spectrometer on the National Ignition Facility at Lawrence Livermore National Laboratory have been calibrated photometrically in the range of 5.5-16 keV. The elliptical geometry provides broad spectral coverage and minimizes the degradation of spectral resolution due to the finite source size. The reflectivity curve of the crystals was measured using a x-ray line source. The integrated reflectivity (R(I)) and width of its curve (ΔΘ) were the measurements of major interest. The former gives the spectrometer throughput, and the latter gives the spectrometer resolving power. Both parameters are found to vary considerably with the radius of curvature of the crystal and with spectral energy. The results are attributed to an enhanced mosaic effect due to the increase in curvature. There are also contributions from the crystal cleaving and gluing processes.

Knowledge of and attitudes expressed toward epilepsy by carers of people with epilepsy: a UK perspective.

OBJECTIVE: The aim of this study was to investigate the knowledge and attitudes possessed by carers of people with epilepsy. METHODS: A postal survey of 2000 carers recruited from the membership list of a UK epilepsy charity was conducted using a standard set of questions. The questions covered their knowledge of epilepsy (e.g., estimating prevalence and identifying causes of epilepsy) and their attitudes (e.g., about the characteristics of people with epilepsy). RESULTS: Overall, 651 carers responded. Only 29% of carers were male, with the majority between 40 and 60 years of age. The majority of respondents (76%) overestimated the prevalence of epilepsy. Twenty-five percent believed that epilepsy was caused by stress. The majority of respondents believed that people with epilepsy were treated differently by others. Only a small percentage believed that people with epilepsy should be barred from such professions as teaching and nursing. CONCLUSIONS: Carers of people with epilepsy generally possessed high levels of knowledge about most aspects of epilepsy, and their attitudes toward those with epilepsy were benign. There were, however, particular groups who were more likely to hold more positive attitudes, and these included younger and better-educated individuals. Limitations of this study include that the sample was self-selected and that only a third of the people to whom the questionnaire was mailed responded.

Multicenter prospective randomized 52-week trial of calcium hydroxylapatite versus bovine dermal collagen for treatment of stress urinary incontinence.

OBJECTIVES: To evaluate the safety and effectiveness of soft-tissue augmentation of the urethral sphincter with calcium hydroxylapatite (CaHA; Coaptite) compared with glutaraldehyde cross-linked bovine collagen (Contigen) in female patients with stress urinary incontinence due to intrinsic sphincter deficiency and without associated urethral hypermobility. METHODS: This 12-month prospective, randomized, comparative, multicenter, single-blind, parallel, clinical trial of CaHA and collagen for soft-tissue augmentation of the urethral sphincter in the treatment of stress urinary incontinence enrolled 296 women. Up to five injections were performed in the first 6 months of the trial. Twelve-month postinjection efficacy data were available for 231 patients. RESULTS: The results indicated that CaHA and collagen were both well tolerated in this study. No systemic adverse events were observed with either product. We used the Stamey Urinary Incontinence Scale to grade the improvement, which was the primary endpoint of the study. At 12 months, 83 (63.4%) of 131 CaHA patients compared with 57 (57.0%) of 100 collagen patients showed improvement of one Stamey grade or more (P = 0.34). More CaHA patients required only one injection (n = 60; 38.0%) during the study compared with the Contigen patients (n = 36; 26.1%; P = 0.034). Also, the average total volume of material injected during the course of the study was less for CaHA than for collagen (4.0 mL versus 6.6 mL, respectively; P <0.0001). CONCLUSIONS: The results of the study have demonstrated that Coaptite is an appropriate and well-tolerated treatment for patients with incontinence due to intrinsic sphincter deficiency. This new soft-tissue augmentation material has a good safety profile and appears to provide durable improvement.

AA2500 testosterone gel normalizes androgen levels in aging males with improvements in body composition and sexual function.

Testosterone replacement in hypogonadal men improves body composition, mood, and sexual functioning. In this 90-d study, we compared the pharmacokinetics and treatment effectiveness of a topical testosterone gel (AA2500) at two concentrations, 50 mg/d and 100 mg/d, to a testosterone patch and placebo gel in 406 hypogonadal men. Pharmacokinetic profiles were obtained, body composition was measured, and mood and sexual function were monitored. AA2500 treatments resulted in dose-dependent improvements in all pharmacokinetic parameters, compared with testosterone patch and placebo. Mean average concentrations at d 90 T were 13.8, 17.1, 11.9, and 7.3 nmol/liter for 50 mg/d AA2500, 100 mg/d AA2500, testosterone patch, and placebo, respectively. At d 90, the 100 mg/d AA2500 treatment improved lean body mass by 1.7 kg and percentage of body fat by 1.2% to a significantly greater degree than either control treatment. Significant improvements in spontaneous erections, sexual desire, and sexual motivation were also evidenced with the 100 mg/d AA2500 dose in comparison with placebo. Testosterone gel was well tolerated; however, the testosterone patch resulted in a high rate of application site reactions. Overall, AA2500 is an effective, well tolerated treatment for hypogonadism.

Male slings for postprostatectomy incontinence.

PURPOSE: Over the past few years, there has been increasing interest in using male slings for postprostatectomy incontinence (PPI). Currently, three different forms of the male sling has been described: one using synthetic materials and two using human fascia or dermis. This article will give a historical perspective on the male sling and describe the surgical techniques and early results using two different types of male slings using fascia or dermis. MATERIALS AND METHODS: From 1997 to 1999, nine patients with PPI underwent a bladder neck sling procedure using a combined perineal and abdominal approach. All patients had a suprapubic incision to expose the rectus muscle and to place a suprapubic tube. Since 1999, we have used a wide cadaveric fascial or dermal sling placed at the proximal bulbar urethra. Using an entirely perineal approach, the sling ends are fixated to the inferior pubic rami using bone anchors. RESULTS: Of 9 patients with bladder neck slings, 6 are dry, 1 is significantly improved, and 2 have failed, at a mean follow-up of 13 months. For the perineal male sling, 26 (45%) of 58 patients were completely dry, and overall 47 (81%) of 58 were significantly improved or were dry at a mean 6 months postoperatively. Neither group had significant complications. CONCLUSIONS: Both male slings appear to be safe and effective procedures for treating PPI; however, longer follow-up and additional experience are needed to determine their true role in the treatment of PPI.

Bone anchored sling for the treatment of post-prostatectomy incontinence.

PURPOSE: This ongoing study evaluates the safety and efficacy of a new minimally invasive sling procedure for treating post-prostatectomy incontinence. MATERIALS AND METHODS: A total of 16 men 56 to 74 years old (mean age 67) underwent the procedure using the Straight-In bone anchoring system. Time after prostatectomy was 1.5 to 5 years (mean 2.5). Of the 16 patients 14 had urodynamically confirmed stress urinary incontinence, while 2 had mixed incontinence with stress incontinence and detrusor instability. The procedure is performed with the patient in the lithotomy position using a perineal approach. Four miniature bone screws with pre-attached pairs of No. 1 polypropylene sutures are placed directly into the medial aspect of the inferior rami of the pubic bone. A pair of bone anchors is placed just below the symphysis on each side, and the second pair is inserted 3 to 4 cm. lower. To support the bulbar urethra a gelatin coated polyethylene terephthalate trapezoid shaped sling or cadaveric fascia lata is tied to the pubic bone using the 4 pairs of sutures attached to the bone anchors. Urethral resistance is increased to 30 to 50 cm. water above baseline pressure. RESULTS: Followup was 4 to 20 months (mean 12.2). Of the 14 men with the preoperative urodynamic diagnosis of genuine stress incontinence 12 were cured of incontinence, defined as subjectively dry with no or only 1 pad used daily for security without any episode of leakage, while 2 were improved subjectively with a decrease of 50% or more in pads daily. Two other patients with the preoperative diagnosis of mixed urinary incontinence were improved. Postoperatively urodynamic study in these patients revealed resolved stress incontinence but persistent urge urinary incontinence. They responded to anticholinergics and are completely dry. Intraoperative and postoperative complications were minimal with no erosion, infection or osseous complications. CONCLUSIONS: This new minimally invasive male sling procedure is safe and efficacious. Adjusting sling tension by measuring urethral resistance results in a low rate of over correction and failure. Further experience is needed to establish this procedure as treatment for post-prostatectomy incontinence.

Double balloon positive pressure urethrography is a more sensitive test than voiding cystourethrography for diagnosing urethral diverticulum in women.

PURPOSE: We determined the relative sensitivity of double balloon positive pressure urethrography and voiding cystourethrography for diagnosing urethral diverticula in women, and for evaluating which presenting symptoms should be considered clinically suspicious for even smaller diverticula. MATERIALS AND METHODS: The series comprised 32 women, including those with new onset urinary tract infections not related to intercourse, menopause or catheters, those with urethral symptoms, such as point urethral tenderness or a mass, urethral pain, dysuria, dyspareunia or post-void dribbling, and those with new onset urgency and frequency. All patients underwent a history and physical examination by the same physician. Each patient underwent double balloon urethrography and voiding cystourethrography on the same day at a single radiology department. RESULTS: Of the 32 women 30 (94%) were diagnosed with at least 1 diverticulum by double balloon urethrography. In 22 of these cases voiding cystourethrography failed to show the diverticulum. Only 11 of these patients (37%) had a palpable mass on clinical examination. The most common presenting symptoms in patients diagnosed with a diverticulum were recurrent urinary tract infection (52%), dysuria (52%), urgency (41%), frequency (38%), stress incontinence (38%) and urge incontinence (34%). Only 3 patients (9%) presented with 1 symptom. Diverticulectomy was performed in 16 patients. Double balloon urethrography had greater sensitivity (100%) than voiding cystourethrography (44%) relative to a confirmed surgical diagnosis (z test p = 0.002). Of 9 diverticula missed by voiding cystourethrography in the surgery group the maximum diameter was less than 15 mm. in 5. Average followup in the surgery cases is 34 months (median 35, range 17 to 50). None of these patients has had new symptoms suggestive of recurrent diverticulum, failure, new urethritis or new stress urinary incontinence. Conservative therapy consisted of long-term antibiotics in 6 patients and symptomatic treatment with short-term antibiotics in the remaining 8. Conservative therapy offered symptomatic relief in most cases but did not prevent recurrent symptoms. CONCLUSIONS: A diverticulum should be suspected in patients with new onset urinary tract infection, urgency and frequency as well as dyspareunia, post-void dribbling and dysuria. Double balloon urethrography is a more sensitive diagnostic test than voiding cystourethrography for diagnosing urethral diverticula. Patients with mild symptoms may be treated with conservative therapy, although we believe that satisfactory long-term treatment of diverticula is best achieved by surgical excision.

Successful transplantation of 50 single unit pediatric kidneys ages 11 to 48 months into adult recipients.

There is currently an imbalance between the need for cadaveric kidneys for transplantation and the supply. The medical criteria for accepting cadaveric donors are changing and organs that were originally thought to be unacceptable have functioned well. Previous reports have discussed the problems with transplanting pediatric allografts less than 4 years old into adult recipients, and the results have not been encouraging. From 1986 to 1991 a total of 50 kidneys ages 11 to 48 months were transplanted as single units into adult recipients (Group A). Ninety-one adult donor cadaveric transplants were used as controls (Group B). The cadaveric transplants were 2nd or 3rd transplants in 7 of the Group A and 12 of the Group B patients. Renal preservation, storage times, and demographics were the same. Prednisone, cyclosporine, and either Minnesota ALG or OKT3 were used for immunosuppression in both groups. Imuran was added in immunologically high-risk patients. The 1-year actuarial patient and allograft survivals for Group A versus Group B were 89.5% versus 94.2% (p=0.49) and 71.3% versus 87.8% (p=0.01), respectively. There was no difference in allograft or patient survival in kidneys from donors 11-24 months of age or 25-48 months (p=0.56). Renal growth, as measured by sonography, occurred while on cyclosporine A. Excretory and hormonal function as measured by creatinine and hematocrit both improved. Seventy percent of the Group A patients and 76% of the Group B patients were free from rejection in the first 2 months post transplantation (p=0.45).(ABSTRACT TRUNCATED AT 250 WORDS)

Renal transplantation into ileal conduits: results and long-term follow-up.

From 1977 through 1990, 708 renal transplants were performed at our institution. Eight of these allografts (1.1%) were placed into recipients who required ileal conduits. This report describes the long-term follow-up of these patients. Five out of 8 patients currently have functioning allografts 29 to 102 months after transplantation (with a mean allograft survival of 50 months). Construction of an ileal conduit in patients without bladders or in those who have non-functioning bladders is a straightforward approach with minimal increased morbidity and good long-term results.

A family practice education system based on patient care outcomes in family practice settings.

The philosophy, goals, objectives, methodology, and results of a family practice faculty development program are described. Developing family practice educators who will create an education system based on patient care outcomes in family practice settings is the central philosophical purpose of this faculty development program. On completion of the program all participants recognized the essential nature of this philosophical goal and were more comfortable and confident in their ability to: (1) determine resident learning needs; (2) organize curriculum units; (3) use different teaching techniques; and (4) understand their own personal teaching needs and interests. The implications of these changes for developing a family practice curriculum based on patient needs are described.