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Menkès syndrome is a sex-linked recessive disease. The authors previously reported a case in a boy whose neurologic condition deteriorated gradually until death occurred at the age of seven and a half months. Diagnosis was confirmed by the finding of very low plasma levels of copper and ceruloplasmin. Evaluation of family members disclosed hypopigmentation of one half of the abdomen in three sisters and in the carrier mother. This hypopigmentation may be ascribed to decreased melanocyte copper-dependant tyrosinase activity. Among cells in the body, this anomaly may be present or absent according to whether or not the abnormal X chromosome is inactivated.  相似文献   
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In order to evaluate in vivo single-photon emission tomography (SPET) method of assessing cerebral function after hypoxic-ischemic injury in human neonates, we studied D1 and D2 dopamine receptors in a rat model. Seven-day-old rats underwent permanent unilateral common carotid ligation followed by exposure to 8% O2. Two weeks later, in brains with no visible loss of hemispheric volume, striatal dopaminergic receptors were studied, with [125I]TISCH and [1251]IBZM for the D1 and D2 dopamine receptors, respectively. Using [125I]TISCH, we observed no modifications of D1 receptors, but in contrast, ex vivo and in vitro autoradiographic experiments showed a 40% decrease in the striatal binding of [125I]IBZM on both the ipsilateral and the contralateral side to the carotid ligation. These alterations were detected with IBZM, a D2 dopamine receptor ligand usable for SPET imaging. Therefore, exploration of D2 receptors by SPET in human neonates suffering from perinatal hypoxia-ischemia may be valuable for the diagnosis and follow-up of cerebral function damages. Correspondence to: D. Guilloteau  相似文献   
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In 7 neonates with cyanotic heart disease, balloon atrial septostomy was performed in the neonatal intensive care unit under two-dimensional echocardiographic control. Trans-umbilical route was used with success in 6 neonates and percutaneous femoral vein in 1 neonate after failure of the trans-umbilical route. The mean transcutaneous oxygen saturation increase was 22%. No complications were observed. The average duration of the procedure was 25 minutes. Thus this technique is efficient, quick and easy to perform, allowing the procedure to be done under optimal environmental conditions in critically ill neonates.  相似文献   
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The DRESS syndrome (Rash with Eosinophilia and Systemic Symptoms) is a drug hypersensitivity reaction poorly known by paediatricians. It occurs within 1 to 8 weeks of treatment. Clinical features associate in variable patterns, fever, rash, lymphadenopathies, arthritis and potentially life-threatening damage (hepatitis, nephritis, pneumonitis), hyperleucocytosis and eosinophilia. This condition must be early recognized in order to immediately stop suspect drugs. A 6.5 year old girl had a febrile rash, hyperleucocytosis, lymph nodes and cytolitic hepatitis probably due to phenobarbital. Diagnosis of DRESS syndrome was performed only 13 days after the beginning of the eruption. Evolution was favorable but characterized by the recurrence of the febrile eruption with pleuritis. DRESS syndrome is a well described disease that occurs during treatment with a number drugs, particularly anti-epileptic drugs. Steroid therapy and immunoglobulins are proposed for treatment but have not been evaluated.  相似文献   
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Summary The effect ofN-(3,4-dimethoxyphenyl)N-methyl-2-(naphthyl)-m-dithiane-2-propylamine hydrochloride (RO11-2933), an analog of the calcium channel blocker tiapamil, on doxorubicin (DOX)-induced cytotoxicity and DNA damage in human ovarian cancer cells sensitive and resistant to DOX was investigated. A2780-DX2, A2780-DX3, and A2780-DX6 cell sublines were characterized by 7-, 26-, and 48-fold resistance after 2 h DOX exposure and 30-, 50-, and 500-fold resistance after 72 h DOX exposure, respectively. Increased drug efflux resulting in a lower intracellular drug accumulation, decreased DOX-induced DNA single-strand breaks (DNA SSBs), and rapid DNA repair correlated with the degree of resistance. In addition, DNA SSBs were rapidly repaired within 8 h in A2780-DX3 cells, whereas no significant repair of DNA SSBs was observed in sensitive cells. In comparison with verapamil, RO11-2933 was found to reverse DOX resistance at lower and nontoxic concentrations (2 M as compared with 10 M verapamil). This reversion was complete in cells with a low degree of resistance (A2780-DX1 and A2780-DX2) but partial in highly resistant cells (A2780-DX3 and A2780-DX6), and continuous exposure to RO11-2933 was essential for optimal reversal of drug resistance. Interestingly, RO11-2933 was found to inhibit the repair of DNA SSBs induced by DOX but not those induced by X-ray. These results suggest that the potentiation of DNA SSBs and the specific inhibition of DNA repair by RO11-2933 in multidrug-resistant cells could be of particular value in overcoming MDR in the clinic.Abbreviations RO11-2933 N-(3,4-dimethoxyphenethyl)-N-methyl-2-(2-naphthyl)-m-dithiane-2-propylamine hydrochloride - DOX doxorubicin-HCl - SSBs single-strand breaks - MDR multidrug resistance This work was supported in part by CA 18420 and CA 21071  相似文献   
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Children born preterm more than average display cognitive difficulties that are significant enough to prevent normal schooling. The aim of our study was to provide better understanding of the long-term neuropathological processes associated with preterm injury, through the hypothesis that mild cognitive disorders might be related to slight deficits in primary functions such as attention and perception. Assessment of auditory pre-attentive processes was performed by recording the obligatory sensory response (N250) and the change-detection response (Mismatch Negativity, MMN). Topographic study of these responses was performed in fifteen 9-year-old children born preterm (27-33 weeks gestational age) matched to fifteen control children born at term. The auditory stimulus sequence consisted of 1000 Hz standard and 1100 Hz deviant tones (15%) delivered binaurally with an interstimulus interval of 700 ms. The results showed that MMN was similar in both groups. Analysis of the responses to standard repetitive tones demonstrated significantly smaller N250 wave amplitude in children born preterm. Scalp current density maps showed that this reduction in amplitude was associated with lower activity of both frontal and left supratemporal generators. Although the functional significance of the N250 wave in children remains to be clarified, our results indicate a disorder of auditory processes related to prematurity that might have consequences on the development of higher-level processes.  相似文献   
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We have developed a four-dimensional computed tomography (4D CT) technique for mapping breathing motion in radiotherapy treatment planning. A multislice CT scanner (1.5 mm slices) operated in ciné mode was used to acquire 12 contiguous slices in each couch position for 15 consecutive scans (0.5 s rotation, 0.25 s between scans) while the patient underwent simultaneous quantitative spirometry measurements to provide a sorting metric. The spirometry-sorted scans were used to reconstruct a 4D data set. A critical factor for 4D CT is quantifying the reconstructed data set quality which we measure by correlating the metric used relative to internal-object motion. For this study, the internal air content within the lung was used as a surrogate for internal motion measurements. Thresholding and image morphological operations were applied to delineate the air-containing tissues (lungs, trachea) from each CT slice. The Hounsfield values were converted to the internal air content (V). The relationship between the air content and spirometer-measured tidal volume (v) was found to be quite linear throughout the lungs and was used to estimate the overall accuracy and precision of tidal volume-sorted 4D CT. Inspection of the CT-scan air content as a function of tidal volume showed excellent correlations (typically r>0.99) throughout the lung volume. Because of the discovered linear relationship, the ratio of internal air content to tidal volume was indicative of the fraction of air change in each couch position. Theoretically, due to air density differences within the lung and in room, the sum of these ratios would equal 1.11. For 12 patients, the mean value was 1.08 +/- 0.06, indicating the high quality of spirometry-based image sorting. The residual of a first-order fit between v and V was used to estimate the process precision. For all patients, the precision was better than 8%, with a mean value of 5.1% +/- 1.9%. This quantitative analysis highlights the value of using spirometry as the metric in sorting CT scans. The 4D reconstruction provides the CT data required to measure the three-dimensional trajectory of tumor and lung tissue during free breathing.  相似文献   
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