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1.
Abstract

Objective: To understand the origin of extremely high gonadotropin levels in a perimenopausal woman.

Methods: A 52-year-old woman with a 2?months of amenorrhea followed spontaneous menstrual cycles recovery was referred to our outpatient clinic with elevated follicle-stimulating hormone (FSH, 483 mUI/ml), luteinizing hormone (LH, 475 mUI/ml) and prolactin (PRL, 173?ng/ml). She was known to take levosulpiride. The gonadotropin levels did not fit with the clinical features.

Results: A gonadotroph tumor was ruled out. Further analysis confirmed constantly high FSH, LH and PRL levels. The measurements were repeated using different analytical platforms with different results. After serial dilutions, nonlinearity was present suggesting an immunoassay interference. After post-polyethylene glycol recovery, hormone levels appeared in the normal range. Anti-goat antibodies were recognized in the serum of the patient.

Conclusions: This case report shows a case of falsely abnormal high gonadotropin and PRL levels in a woman during menopause transition. In the clinical practice the evaluation of gonadotropin profile is not recommended at this age, but the abnormal levels stimulated further evaluation. An interference in the assay due to anti-goat antibodies resulted in abnormally high level of FSH and LH. A strict collaboration between clinicians and the laboratory is needed, when laboratory findings do not correspond to clinical findings.  相似文献   
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Regioisomers of pyrene and benzo[a]pyrene quinones were testedfor their ability to induce structural and numerical aberrationsand spindle disturbance in Chinese hamster epithelial liver(CHEL) cells in culture. All quinones tested were clastogenicPyrene-1,8-quinone (P-1,8-Q) and benzo[a]pyrene–3,6–quinone(BP-3,6-Q) induced strikingly high levels of triradials. Inaddition, dicentrics and ring chromosomes were very common inBP-3,6-Q-treated cultures. Isomers of these compounds, pyrene-1,6-quinone(P-1,6-Q) and benzo[a]pyrene-1,6-quinone (BP-1,6-Q), inducedunobtrusive patterns of chromosomal aberrations. We suspectthat the P-1,8-Q and BP-3,6-Q moieties bound to the DNA werestill reactive, and formed crosslinks and/or underwent redoxcycling leading to high local concentrations of reactive oxygenspecies. In addition, P-1,8-Q and BP-3,6-Q induced c-mitoses,hyperdiploidies and polyploidies, in particular endoreduplications.These effects were not seen with the other two test compounds,or they were only detected at the highest concentrations used,which were strongly cytotoxic (c-mitoses with P-1,6-Q, polyploidieswith BP-1,6-Q). 6To whom correspondence should be addressed at: European Centre for the Validation of Alternative Methods (ECVAM), Joint Research Centre (JRC), TP58O, 1–21020 Ispra, Italy  相似文献   
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The reversibility of the configurational photoisomerization process of bilirubin (BR) with laser lines in the blue-green spectral region is investigated. Photoisomerization efficiency of BR is found to depend strongly on wavelength, and to decrease when the excitation wavelength is increased from blue to green. Reversion of BR photoisomers (identical to photobilirubin, PBR) back to native BR is demonstrated for several laser lines by irradiating PBR/BR mixtures with wavelengths greater than the excitation wavelengths. Green lines turn out to be very efficient for PBR----BR reversion. The PBR concentrations at photoequilibrium, obtained from the spectrophotometric data, are in close agreement with the corresponding values measured with the high performance liquid chromatography technique in the case of 10 nm bandwidth filtered light reported in the literature. The 457 nm blue laser line produces 32% PBR concentration at photoequilibrium; only 14, 7, and 3% PBR concentrations are produced by the blue-green lines at 488, 501, 514 nm, respectively. The effect on the photostationary PBR/BR mixture of successive irradiations with different wavelengths, and the influence of the wavelength sequence are reported. In the case of blue lines our results support the assumption of the first-order kinetics for the BR in equilibrium PBR photoreaction. Departures are observed with green-lines (501, 514 nm). The present results, together with the i) good clinical efficiency reported for fluorescent green lamps; and ii) slow elimination of configurational photoisomers in infants, tend to confirm the lumirubin-pathway as the main mechanism for phototherapy, and call for clinical investigation of narrow-spectrum lamps with peak emission wavelength in the (biologically safer) 480 divided by 530 nm range.  相似文献   
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The relative efficacy of fluorescent green (Sylvania F20T12/G) and "special" blue (Westinghouse F20T12/BB) lamps in the phototherapy of jaundiced neonates was investigated. Two groups of low birth weight infants with a mean gestational age of 35 weeks and mean birth weight of 1930 gm, who developed hyperbilirubinemia within the first 5 days of life, were given green or blue lamp phototherapy under the same irradiation conditions. No statistically significant difference in plasma bilirubin concentrations was found between the two groups after 24 or 48 hours of treatment. Because recent measurements indicate that green lamps are much less efficient than special blue lamps for the production of Z, E isomers of bilirubin in vitro and in vivo, the clinical equivalence of these two types of lamps seems to support the hypothesis that production of structural photoisomers of bilirubin is the main mechanism of phototherapy in humans. Therefore, fluorescent green lamps provide an alternative to special blue lamps for treatment of neonatal hyperbilirubinemia.  相似文献   
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