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71.
Recurrent epistaxis is a common pediatric problem with uncertain etiology in most cases. We observed frequent complaints, or history of epistaxis in children with migraine. The aim of this study was to determine whether there is an association between epistaxis and migraine in children. A detailed questionnaire was used to conduct a study of 45 consecutive patients, ages 6-11 years, with migraine, diagnosed according to the 1997 proposed pediatric revisions to the International Headache Society criteria; the patients were evaluated in our Pediatric Neurology Clinic. Control subjects consisted of 64 children without recurrent headaches, matched as a group for age and sex, and drawn as a convenient sample from two general pediatric practices and an elementary school. Sixteen (36%) of 45 patients with migraine had epistaxis as compared with 7 (11%) of 64 control subjects (odds ratio = 4.5; 95% confidence interval 1.6-12.1; P = 0.002). Epistaxis began an average of 3 years before migraine with similar characteristics to idiopathic epistaxis in habitual nose-bleeders, such as onset in early childhood, high incidence in sleep, and family history of epistaxis. This study demonstrates a significant association between migraine and recurrent epistaxis in children. Recurrent epistaxis increased the odds of migraine more than fourfold. Moreover, these data raise the question of whether epistaxis may represent a precursor to childhood migraine. The two disorders may share a common pathogenesis, and a prospective, longitudinal study is required to define further the relationship between them. 相似文献
72.
PURPOSE: Focal cortical dysplasia (CD) is characterized by the presence of dysmorphic neurons, laminar and columnar disorganization. A few patients with CD have balloon cells intermixed with dysmorphic neurons. The cellular characteristics of balloon cells remain unknown. This study was intended to determine further the cellular characteristics of balloon cells. METHODS: Neocortical tissue resected from five patients with medically intractable focal epilepsy due to CD was studied. The presence of balloon cells (large opalescent cells with eccentric nuclei) was confirmed in all five patients by using cresylecht violet staining. Immunocytochemistry used antibodies against markers of pluripotential stem cells (CD133), multipotential progenitor cells (nestin), antiapoptotic gene products (Bcl-2), immature neurons (beta-tubulin 3, TUJ1), immature glia (vimentin), mature neurons (MAP2 and NeuN), and astrocytes (glial fibrillary acidic protein; GFAP). RESULTS: Balloon cells (BCs) were found to be immunoreactive to Bcl-2 (46%), vimentin (41%), Nestin (28%), CD133 (28%), MAP2 (27%), GFAP (14%), and TUJ1 (10%). An extremely small number of BCs were immunopositive for NeuN. Confocal double labeling showed that balloon cells were dually immunopositive for CD133/nestin; CD133/GFAP; CD133/Bcl-2, and nestin/GFAP. CONCLUSIONS: These results show that balloon cells are heterogeneous cell populations expressing cell-surface markers for pluripotential stem cells and proteins for multipotent progenitors, or immature neurons/glia. The presence of stem cell/progenitor markers in the balloon cells could be due to a persistent postnatal neurogenesis or early embryonic insult that resulted in arrest of proliferation/differentiation at their early stages. Additionally, the coexpression of Bcl-2 in CD133-positive balloon cells suggests that a resistance to programmed cell death may be involved in the pathogenesis of cortical dysplasia. 相似文献
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Assessing the impact of restricted intrauterine growth on neonatal frontal lobe (FL) dimensions is important. We aimed to create a sonographic nomogram of FL dimensions in neonates at different gestational ages (GA) and evaluate the impact of small head circumference (HC) on FL dimensions. We conducted sonographic biometry of the FL at birth. We included 218 newborn infants born at GA of 24-43 wk: appropriate for GA and normal HC (n = 178), and small for GA and small HC (n = 23). Infants with a 5-min Apgar score <7, severe congenital malformations, or chromosomal abnormalities were excluded. Through a coronal ultrasound scan via the anterior fontanelle at the level where the most lateral point of the left Sylvian fissure was best demonstrated, we drew a triangle connecting the most lateral point of the Sylvian fissure, the corpus callosum, and the subcalvarian point of the interhemispheric fissure. We measured the three sides of the triangle, Sylvian-fontanellar distance, Sylvian-callosal distance, and fontanellar-callosal distance, and calculated the frontal triangular area. All four FL dimensions increased significantly between 24 and 43 wk of gestation in both appropriate for GA-normal HC and small for GA-small HC neonates, and were strongly correlated with HC and birth weight. Regression lines of GA against Sylvian-fontanellar distance, Sylvian-callosal distance, fontanellar-callosal distance, and frontal triangular area in the appropriate for GA-normal HC group differed significantly from those of the small for GA-small HC group (p < 0.05). Male neonates had significantly larger Sylvian-fontanellar and Sylvian-callosal distances than females (p < 0.01 and p < 0.015, respectively). In conclusion, FL measures increased significantly between 24 and 43 wk of gestation, and were strongly correlated with HC. We speculate that a sonographically small fetal HC implies growth restriction of the fetal FL. 相似文献
76.
OBJECTIVE: To review the role of sincalide in treating and preventing parenteral nutrition (PN)-associated gallbladder disease. DATA SOURCES: A MEDLINE (1996-March 2004) search was performed using the key terms cholecystokinin, sincalide, parenteral nutrition, cholelithiasis, cholestasis, and sludge. DATA SYNTHESIS: Five human studies investigated the safety and efficacy of sincalide in patients with PN-associated gallbladder disease. Sincalide at intravenous doses of 0.04 microg/kg 3 times daily increased bile flow and improved serum bilirubin levels. However, patients with advanced liver disease did not respond to sincalide therapy. Long-term follow-up data on sincalide effects on liver disease progression are not yet available. CONCLUSIONS: Sincalide improved the signs of cholestasis. However, its long-term effects in preventing and treating PN-associated gallbladder disease remain unknown and its routine use for this indication cannot be recommended at this time. 相似文献
77.
Chander S Ergun EL Zak IT Zingas AP Bloom DA Joyrich RN Getzen TM Shaman M 《Clinical nuclear medicine》2004,29(5):296-299
The authors describe various patterns of F-18 fluorodeoxyglucose (FDG) accumulation in the diaphragm and crura. They present 6 patients in whom incidental diaphragmatic and crural uptake of FDG was observed during positron emission tomography (PET). Hyperventilation is thought to be the potential underlying mechanism of this condition. 相似文献
78.
Damaj MI Carroll FI Eaton JB Navarro HA Blough BE Mirza S Lukas RJ Martin BR 《Molecular pharmacology》2004,66(3):675-682
Bupropion is an atypical antidepressant that also has usefulness as a smoking-cessation aid. Because hydroxybupropion, a major metabolite of bupropion, is believed to contribute to its antidepressant activity, this metabolite may also contribute to the smoking-cessation properties of bupropion. This study investigated the effects of hydrobupropion enantiomers on monoamine transporters and nicotinic acetylcholine receptor (nAChR) subtypes. Racemic bupropion and hydroxybupropion inhibit [(3)H]norepinephrine (NE) uptake with similar potency (IC(50) values of 1.9 and 1.7 microM, respectively), but most of the latter activity resides in the (2S,3S)-hydroxy isomer (IC(50) = 520 nM) rather than (2S,3R)-hydroxybupropion (IC(50) > 10,000 nM). Similar results were found with [(3)H]dopamine (DA) uptake. The effects of bupropion and enantiomers of hydroxybupropion on human nAChR subtypes indicate that the (2S,3S) isomer is more potent than the (2S,3R) isomer or racemic bupropion as an antagonist of alpha(4)beta(2) (functional IC(50) = 3.3 microM). In addition, (2S,3S)-hyroxybupropion and bupropion were considerably more potent than (2R, -3R)-hydroxybupropion in a mouse depression model (forced swimming test) and in antagonism of acute nicotine effects in mice. Together, our results suggest that clinical and behavioral effects of bupropion arise from actions at nAChR as well as DA and NE transporters. Furthermore, our data suggest that the (2S,3S)-hydroxybupropion isomer may be a better drug candidate for smoking cessation than bupropion because of its higher potency at the relevant targets. 相似文献
79.
Uthman I 《Current opinion in pharmacology》2004,4(2):177-182
Systemic vasculitis represents a broad range of diseases characterized by the presence of blood vessel inflammation. Immunosuppressive therapy forms the foundation of treatment for almost all forms of systemic vasculitis. Newer agents such as mycophenolate mofetil, rituximab and tumour necrosis factor-alpha inhibitors are finding new indications in the therapy of conditions such as systemic lupus erythematosus, idiopathic thrombocytopenic purpura, skin vasculitis, cytoplasmic antineutrophil antibodies-positive vasculitis, sarcoidosis, ocular inflammation, nephritis, inflammatory bowel disease and Takayasu's arteritis. However, older agents such as methotrexate, cyclophosphamide and interferon-alpha are still being explored for newer, more effective and less toxic indications in conditions such as giant cell arteritis and cutaneous polyarteritis nodosa. 相似文献
80.
PURPOSE: Malformations of cortical development (MCDs) are a frequent cause of refractory epilepsy in humans. The in utero radiation model in rats shares many clinical and histopathologic characteristics with human MCDs. Previous studies reported the presence of clinical seizures in radiated rats, but also suggested a dose-dependent differential effect. METHODS: Time-pregnant Sprague-Dawley rats were irradiated on embryonic day E17 with 100 cGy (low dose), 145 cGy (medium dose), 175 cGy (high dose), or were left untreated. Their adult litters were implanted with bifrontal epidural and hippocampal depth electrodes and underwent long-term video-EEG monitoring. After 2 weeks of monitoring, the animals were killed and their brains processed for histological studies. RESULTS: Spikes were most frequently found in the rats that were subjected to low- and medium-dose radiation at E17 and were less frequently seen in the animals that were subjected to high-dose radiation. No interictal spikes were found in any of the control animals. Seizures were recorded in three of five animals of the medium-dose group. Histological studies showed a dose-dependent decrease in cortical thickness as well as an increase of cortical and hippocampal disorganization. CONCLUSIONS: In vivo epileptogenicity in radiated animals was present only in mild or moderate MCD. No in vivo epileptogenicity was seen in severe radiation-induced MCD. 相似文献