Lichen sclerosus Mistaken for Sexual Abuse--Prevention of Victimization.

This case report describes the forensic examination of 7 girls aged between 4-11 years with suspected sexual abuse. The children had been reported by local pediatricians, hospital physicians or authorities such as the youth welfare office and police due to mucosal changes in the anogenital area. All children presented with a clearly delimited, porcelain-like white discoloration of the skin in the anal and genital area with atrophic conversion to parchment-like skin. The markedly vulnerable skin exhibited very different manifestations of hemorrhagic dermal and mucosal defects in the area of the labia, the clitoris, the perineum and the perianal region. The hymen was intact in all cases. The skin changes are typical of lichen sclerosus et atrophicus, which is more common in prepubertal girls and post-menopausal women. Due to the chronic course, affected persons can develop sclerotic plaques, synechia of the labia minora and stenoses of the urinary tract and of the vaginal orifice, so that an early diagnosis is crucial. This condition is not infrequently taken by attending physicians as a sign of suspected sexual abuse, as the relevant findings are not recognized correctly. Furthermore, there are far-reaching consequences for the affected families, who are often faced with criminal prosecution, a breakdown of social familial structures and an enormous psychological burden for the affected persons. To avoid victimization there is an urgent need for more information about the differential diagnoses of sexual abuse and a call for interdisciplinary co-operation when evaluating abnormal anogenital findings in children.

Imaging of copper, zinc, and other elements in thin section of human brain samples (hippocampus) by laser ablation inductively coupled plasma mass spectrometry.

Laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS) was used to produce images of element distribution in 20-microm thin sections of human brain tissue. The sample surface was scanned (raster area approximately 80 mm(2)) with a focused laser beam (wavelength 213 nm, diameter of laser crater 50 microm, and laser power density 3 x 10(9) W cm(-2)) in a cooled laser ablation chamber developed for these measurements. The laser ablation system was coupled to a double-focusing sector field ICPMS. Ion intensities of 31P+, 32S+, 56Fe+, 63Cu+, 64Zn+, 232Th+, and 238U+ were measured within the area of interest of the human brain tissue (hippocampus) by LA-ICPMS. The quantitative determination of copper, zinc, uranium, and thorium distribution in thin slices of the human hippocampus was performed using matrix-matched laboratory standards. In addition, a new arrangement in solution-based calibration using a micronebulizer, which was inserted directly into the laser ablation chamber, was applied for validation of synthetic laboratory standard. The mass spectrometric analysis yielded an inhomogeneous distribution (layered structure) for P, S, Cu, and Zn in thin brain sections of the hippocampus. In contrast, Th and U are more homogeneously distributed at a low-concentration level with detection limits in the low-nanogram per gram range. The unique analytical capability and the limits of LA-ICPMS will be demonstrated for the imaging of element distribution in thin cross sections of brain tissue from the hippocampus. LA-ICPMS provides new information on the spatial element distribution of the layered structure in thin sections of brain tissues from the hippocampus.

Trace analysis of high-purity graphite by LA-ICP-MS.

Laser-ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) has been established as a very efficient and sensitive technique for the direct analysis of solids. In this work the capability of LA-ICP-MS was investigated for determination of trace elements in high-purity graphite. Synthetic laboratory standards with a graphite matrix were prepared for the purpose of quantifying the analytical results. Doped trace elements, concentration 0.5 microg g(-1), in a laboratory standard were determined with an accuracy of 1% to +/- 7% and a relative standard deviation (RSD) of 2-13%. Solution-based calibration was also used for quantitative analysis of high-purity graphite. It was found that such calibration led to analytical results for trace-element determination in graphite with accuracy similar to that obtained by use of synthetic laboratory standards for quantification of analytical results. Results from quantitative determination of trace impurities in a real reactor-graphite sample, using both quantification approaches, were in good agreement. Detection limits for all elements of interest were determined in the low ng g(-1) concentration range. Improvement of detection limits by a factor of 10 was achieved for analyses of high-purity graphite with LA-ICP-MS under wet plasma conditions, because the lower background signal and increased element sensitivity.

A new strategy of solution calibration in laser ablation inductively coupled plasma mass spectrometry for multielement trace analysis of geological samples.

Because multielement trace analysis by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) is often limited by the lack of suitable reference materials with a similar matrix composition, a novel quantification strategy using solution calibration was developed. For mass spectrometric multielement determination in geological samples a quadrupole-based LA-ICP-MS is coupled with an ultrasonic nebulizer (USN). In order to arrange matrix matching the standard solutions are nebulized with a USN during solution calibration and simultaneously a blank target (e.g. lithium borate) is ablated with a focused laser beam. The homogeneous geological samples were measured using the same experimental arrangement where a 2% nitric acid is simultaneously nebulized with the USN. Homogeneous targets were prepared from inhomogeneous geological samples by powdering, homogenizing and fusing with a lithium borate mixture in a muffle furnace at 1050 degrees C. Furthermore, a homogeneous geological glass was also investigated. The quantification of analytical results was performed by external calibration using calibration curves measured on standard solutions. In order to compare two different approaches for the quantification of analytical results in LA-ICP-MS, measured concentrations in homogeneous geological targets were also corrected with relative sensitivity coefficients (RSCs) determined using one standard solution only. The analytical results of LA-ICP-MS on various geological samples are in good agreement with the reference values and the results of other trace analytical methods. The relative standard deviation (RSD) for trace element determination (N = 6) is between 2 and 10%.

Determination of trace elements in zeolites by laser ablation ICP-MS.

Laser ablation inductively coupled plasma mass spectrometry using a quadrupole-based mass spectrometer (LA-ICP-QMS) was applied for the analysis of powdered zeolites (microporous aluminosilicates) used for clean-up procedures. For the quantitative determination of trace element concentrations three geological reference materials, granite NIM-G, lujavrite NIM-L and syenite NIM-S, from the National Institute for Metallurgy (South Africa) with a matrix composition corresponding to the zeolites were employed. Both the zeolites and reference materials were fused with a lithium borate mixture to increase the homogeneity and to eliminate mineralogical effects. In order to compare two different approaches for the quantification of analytical results in LA-ICP-MS relative sensitivity coefficients (RSCs) of chemical elements and calibration curves were measured using the geostandards. The experimentally obtained RSCs are in the range of 0.2-6 for all elements of interest. Calibration curves for trace elements were measured without and with Li or Ti as internal standard element. With a few exceptions the regression coefficients of the calibration curves are better than 0.993 with internal standardization. NIM-G granite reference material was employed to evaluate the accuracy of the technique. Therefore, the measured concentrations were corrected with RSCs which were determined using lujavrite reference material NIM-L. This quantification method provided analytical results with deviations of 1-11% from the recommended and proposed values in granite reference material NIM-G, except for Co, Cs, La and Tb. The relative standard deviation (RSD) of the determination of the trace element concentration (n = 5) is about 1% to 6% using Ti as internal standard element. Detection limits of LA-ICP-QMS in the lower microg/g range (from 0.03 microg/g for Lu, Ta and Th to 7.3 microg/g for Cu, with the exception of La) have been achieved for all elements of interest. Under the laser ablation conditions employed (lambda: 266 nm, repetition frequency: 10 Hz, pulse energy: 10 mJ, laser power density: 6 x 10(9) W/cm2) fractionation effects of the determined elements relative to the internal standard element Ti were not observed.

[Stimulation of growth hormone and prolactin secretion with TRH in acromegaly (author's transl)]. / Stimulation der Wachstumshormon- und Prolactin-Sekretion durch TRH bei Akromegalie

Inappropriate stimulation of growth hormone (hGH)-secretion with TRH in acromegalic subjects has been shown previously, whereas prolactin (hPRL) secretion was reported to be blunted in active acromegaly. In this study TRH induced hGH and hPRL secretion was investigated in 23 active (mean hGH level: 68.5 +/- 19.9 ng/ml; +/- SE) and 15 inactive acromegalics (mean hGH level: 2.3 +/- 0.4 ng/ml; +/- SE). Fourteen of the active acromegalics showed a significant increase up to more than double of the basal hGH level after 200 mug TRH while in only one of the inactive acromegalics an inappropriate rise of hGH was induced by TRH. Basal hPRL levels were elevated in 9 and within normal range in 14 of the patients with active acromegaly. Except in 3 patients who had normal basal hPRL levels and in one patient with excessively elevated hPRL and hGH levels due to an hPRL and hGH producing adenoma, all patients had normal hPRL responses to TRH. In those with inactive acromegaly, 9 had hPRL levels below normal and only , out of the 15 patients showed a normal rise of hPRL after TRH. The patients who showed no hPRL response to TRH demonstrated also other signs of pituitary insufficiency due to the operative procedure. In contrast to a previous report these findings demonstrate that normal or enhanced hPRL secretion is found in active acromegaly. The inappropriate rise of hGH after TRH is compatible with a loss of specificity of the receptor for GRH of the adenoma cell and can be found also in patients with normal basal hGH levels after treatment suggesting that remaining adenoma tissue is present in the pituitary fossa.