High-resolution angular beam stability monitoring at a nanofocusing beamline.

Two semi-transparent imaging beam-position monitors developed at the ESRF have been installed at the micro-analysis beamline ID22 for monitoring the angular stability of the X-ray beam. This system allows low-frequency (10 Hz) angular beam stability measurements at a submicroradian range. It is demonstrated that the incoming macro-beam angular fluctuations are one of the major sources of focal spot instabilities downstream of the Kirkpatrick-Baez mirrors. It is also shown that scanning the energy by rotating the so-called fixed-exit monochromator induces some unexpected angular beam shifts that are, to a large extent, deterministic.

New cryogenic environment for beamline ID22 at the European Synchrotron Radiation Facility.

A compact minicryostat has been well adapted on the hard x-ray microprobe ID22 of the European Synchrotron Radiation Facility. For variable low-temperature investigations, its special technical design provides precise scanning microscopy and allows easy access for multiple detection modes. Based on x-ray excited optical luminescence technique on the micrometer scale, details of the equipment, its temperature calibration, and typical results are described. Data collections from InAs quantum heterostructures support the excellent thermal performance of the novel cryogenic device.

[Two rare case reports of ureteral triplication]. / A propos de deux cas rares de triplication urétérale.

Triplication of the upper urinary tract is rare. It is classified according to its extent and four types have been documented. Since the first description of ureteral triplication by Wrany only about a hundred cases have been reported in the literature. Paediatric cases are very few and female patients seem more concerned. The embryological event resulting in ureteral triplication derives from multiple ureteral buds arising from the Wolffian duct with fissuring of one or more of them. We report on two cases of ureteral triplication. The first one associated with an extravesical ectopic ureter and a dysplasic kidney. Diagnosis was particularly difficult and treatment consisted of total nephrectomy. The second case was associated with an upper pole hydronephrosis and a partial nephrectomy was realized.

[Testicular microlithiasis and cryptorchism: ultrasound analysis after orchidopexy]. / Microlithiases testiculaires et cryptorchidie: analyse échographique à distance de l'orchidopexie.

OBJECTIVE: To evaluate the testicular ultrasound features and frequency of testicular microlithiasis in a population of patients operated several years before for cryptorchidism, in order to define a group at possible increased risk of testicular cancer. MATERIAL AND METHODS: This was a retrospective study of 202 patients, 63 of whom were reviewed by ultrasound with a mean follow-up of 9 years 3 months (7 years 5 months to 11 years 7 months). RESULTS: 32% of operated testes were hypotrophic compared to the correctly descended side; their mean volume was 9.42 ml versus 11 ml for the nonoperated side. 14.3% of surgically descended testes presented an ultrasonographically heterogeneous parenchyma and microlithiasis were present in 9.52% of cases. CONCLUSION: The association between microlithiasis and cryptorchidism is not an incidental finding. Apart from the relative hypotrophy of the testis, ultrasound also revealed, in our study, that the presence of microlithiasis is not an extremely rare finding. Annual ultrasound surveillance is therefore required due to the risk of malignant transformation of these microlithiases.

Incidence of urinary tract infection in neonates with antenatally diagnosed ureteroceles.

PURPOSE: To evaluate the incidence of neonatal urinary tract infection (UTI) in the presence of a ureterocele. PATIENTS AND METHODS: Fifteen successive patients with antenatally detected ureteroceles were reviewed between 1991 and 1996. Sixteen ureteroceles were treated (in one patient they were bilateral). Seven ureteroceles were intravesical, and nine were ectopic. Fourteen patients had a duplex upper tract associated with a ureterocele. One patient had one duplex upper tract and one simple upper tract, both associated with a ureterocele. RESULTS: Of the fifteen neonates with a ureterocele, eight already had a UTI on admission. Of these, three had had prophylactic antibiotics. Of the eight infected patients, seven were symptomatic (three with septicaemia). CONCLUSION: If diagnosed antenatally, obstruction has to be relieved as early as possible during the first week of life as antibiotic prophylaxis alone is not sufficient to avoid UTI in these patients. The authors point out the high frequency of UTI in patients with ureterocele.

Incontinence and constipation after low anorectal malformations in a boy.

BACKGROUND: Low anorectal malformations are considered to be a benign type of anorectal malformations. Their treatment is simple in the neonatal period and gives good results as far continence is concerned. METHODS: We studied a group of 55 boys with low anorectal malformations which had been surgically treated between the 1st January 1975 and the 31st December 1992. We studied the initial treatment and the associated anomalies, 5 patients have died. 27 were seen for an interview and a clinical examination. Extra investigations (anorectal manometry or electromyography of external sphincter) were only offered to consenting patients with an ongoing problem. RESULTS: 3 to 20 years had passed since their operations. Associated anomalies had been found in 11 children. The initial treatment was a perineal procedure in 20 cases and a colostomy in 8 cases. Dilatations were carried out on 11 children. Faecal and urinary continence had been acquired before 30 months of age. 13 children (48%) had problems of soiling and/or chronic constipation. There was no difference between these children and the 14 continent ones regarding the type of malformation, the initial treatment and the follow-up. Anorectal manometry (performed on 9 cases) showed 4 anorectal dyssynergies. It was normal in 3 cases. The Recto Anal Inhibitory Reflex was always present. CONCLUSION: Problems of continence are not rare in the evolution of low anorectal malformations. We suggest therefore a long-term clinical follow-up for those children, with one anorectal manometry control being performed after continence is acquired.

Feasibility and Realization of Single-Pulse Laue Diffraction on Macromolecular Crystals at ESRF.

Laue diffraction patterns with an exposure time of ca 60 ps have been acquired at the European Synchrotron Radiation Facility (ESRF) on protein crystals by using the single-bunch mode of the storage ring. A 10 ns laser pulse initiating photodissociation was synchronized with the X-ray pulse. The potential for a quantitative detection of conformational changes in proteins on the nanosecond timescale with this technique is demonstrated using the example of carbonmonoxymyoglobin, from simulations and real data. The instrumental aspects of the experiment (highly intense X-ray beam, fast shutter system, Laue camera, detector, laser apparatus and synchronization technique) are emphasized.