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61.
Adil M. Al-Nahhas Seishi Jinnouchi Constantinos Anagnostopoulos Wolfgang Hirsch Tom Heary V. Ralph McCready 《European journal of nuclear medicine and molecular imaging》1995,22(2):148-153
Benign myocardial uptake of technetium-99m labelled phosphates, not related to cardiac or metabolic disorders, has been documented except in the case of99mTc-methylene diphosphonate (MDP). The aim of this study was to assess the frequency of myocardial uptake and its possible association with malignant tumours in general and prostatic carcinoma in particular. We reviewed bone scintigrams performed with either99mTc-hydroxydiphosphonate (HDP) or99mTc-MDP over a period of more than 2 years for all patients with prostatic carcinoma and a matching group of patients suffering from other malignant and non-malignant disorders. A total of 965 scintigrams of 812 patients (males=559, females=253; age range 50–91 years, average age 69.2 years) were reviewed. Increased myocardial uptake was detected in 19 scintigrams (MDP=13, HDP=6) of 18 patients (17 males, one female). Most of the male patients with increased myocardial uptake had prostatic carcinoma (13/17) and were over 80 years of age (12/17). All patients were free of any cardiac or noncardiac disorder that might account for such uptake. When scintigraphy was repeated in the same patient, the uptake of99mTc-HDP was more diffuse and of higher grade than that of99mTc-MDP Benign myocardial uptake of99mTc-MDP is more common than previously thought. Although uptake of radiophosphates is attributed to asymptomatic atherosclerotic changes associated with old age, a strong association with prostatic carcinoma exists which may indicate variations in the bone: soft tissue affinity of different MDP complexes. 相似文献
62.
J. D. Becker J. Honerkamp J. Hirsch U. Fröbe E. Schlatter R. Greger 《Pflügers Archiv : European journal of physiology》1994,426(3-4):328-332
Ion channel current amplitudes () and open probabilities (P
o) have been analysed so far by defining a 50% threshold to distinguish between open and closed states of the channels. With this standard method (SM) it is very difficult or even impossible to analyse channels of different size in one membrane patch correctly. A stochastical model, named the hidden Markov model (HMM), separates between observation noise and the stochastic process of opening and closing of ion channels. The HMM allows the independent analysis of , P
o, and mean dwell times () of different channels in one membrane patch, without defining threshold levels. Using this method errors in the analysis are not summarized like in the SM because all different analysing procedures (e. g. filtering, setting of threshold, fitting processes) are done in one step. Two different K+ channels in excised basolateral membranes of the cortical collecting duct of rat (CCD) were analysed by the SM and the HMM. The value of the intermediate-conductance K+ channel (i-K+) was 3.9±0.1 pA (SM) and 3.8±0.2 pA (HMM) for 11 observations. The P
o value of this channel was 10.2±4.2% (SM) and 10.1±4.0% (HMM). The mean values were 5.4±0.6 ms for the open state and 9.6±2.2 ms and 145±21 ms for the closed states (SM) and 7.8±1.1 ms, 7.7±0.9 ms and 148±24 ms (HMM), respectively. For seven small-conductance K+ (s-K+) channels, which were found in the same membrane patches as the i-K+, an accurate analysis of P
o and was not possible with the SM. The value was 1.0±0.1 (SM), 0.9±0.1 (HMM) pA. P
o was 16.6±4.6%, the open value was 11.1±2.8 ms, and the closed value was 34.9±8.5 ms. The HMM allows the analysis of single-channel currents, P
o, and mean values when different or more than one ion channel(s) are colocalized in one membrane patch. Where analysis with the SM was possible results did not significantly differ from those obtained with the HMM. Thus for this kind of analysis the method of setting a 50% threshold appears justified. 相似文献
63.
Surgery of epilepsy associated with focal lesions in childhood 总被引:15,自引:0,他引:15
Bourgeois M Sainte-Rose C Lellouch-Tubiana A Malucci C Brunelle F Maixner W Cinalli G Pierre-Kahn A Renier D Zerah M Hirsch JF Goutières F Aicardi J 《Journal of neurosurgery》1999,90(5):833-842
OBJECT: Surgery in children with epilepsy is a new, evolving field. The important practical issues have been to define strategies for choosing the most suitable candidates and the type and optimal timing of epilepsy surgery. This study was undertaken to elucidate these points. METHODS: To identify the factors that correlated with outcome, the authors analyzed a series of 200 children (aged 1-15 years (mean 8.7 years) who underwent surgery between 1981 and 1996 at the H?pital Necker-Enfants Malades. In 171 cases (85.5%) the epilepsy was medically refractory and was associated with focal cortical lesions. Surgery consisted of resection of the lesion without specifically attempting to identify and remove the "epileptogenic area. "In the group of children whose seizures were medically refractory, the mean follow-up period was 5.8 years. According to Engel's classification, 71.3% of these children became seizure free (Class 1a,) whereas 82% were in Class I. A multivariate statistical analysis revealed that among all the factors studied, the success of surgery in a patient in whom there was a good clinical/electroencephalogram/imaging correlation depended on the patient's having undergone a minimally traumatic operation, a complete resection of the lesion, and a short preoperative seizure duration. After the surgical control of epilepsy, behavior disorders were more improved (31% of all patients) than cognitive function (25%). The patient age at onset, duration and frequency of seizures, intractability of the disease to therapy, and seizure characteristics were correlated with cognitive, behavioral, and academic performance pre- and postoperatively. Multivariate statistical analysis revealed that cognitive dysfunction correlated highly with the duration of epilepsy prior to surgery, whereas behavioral disorders correlated more with seizure frequency. CONCLUSIONS: These data must be taken into account when selecting patients for surgical treatment and when deciding the timing of surgery. Early surgical intervention allows for optimum brain development. 相似文献
64.
Redmond EM Cahill PA Hirsch M Wang YN Sitzmann JV Okada SS 《Thrombosis and haemostasis》1999,81(2):293-300
Plasminogen activator (PA) expression plays an important role in smooth muscle cell (SMC) migration and may therefore contribute to mechanical force-induced arterialization of vein grafts. The aim of this study was to determine whether pulse pressure due to pulsatile flow modulates SMC migration via urokinase (u-PA)-dependent mechanisms. Using a perfused transcapillary culture system, human umbilical vein SMC were exposed to pulse pressures (0-56 mmHg), in the absence or presence of human umbilical vein endothelial cells (EC) by varying pulsatile flow rates (0 ml/min to 25 ml/min). SMC cultured in the absence of EC increased their migration following exposure to increased pulse pressure (248+/-14%). Both u-PA and matrix metallo-proteinase 1 (MMP-1) expression was significantly elevated in SMC exposed to pressure as compared to static controls. The role of proteases in the pulse pressure-induced enhancement of SMC migration was confirmed following pretreatment with aprotinin, an anti u-PA antibody and metalloproteinase inhibitors (181+/-14% for aprotinin vs. 256+/-25% for control, 108+/-4% for anti-u-PA antibody vs. 233+/-17% for non-immune IgG, and 114+/-9% for BB-94, 105+/-7% for BB-3103 vs. 222+/-5% for control). Using SMC derived from u-PA gene knock-out mice, the SMC migratory response to increased pulse pressure was completely inhibited despite a significant increase in MMP expression in these cells. These results suggest that pulse pressure due to pulsatile flow induces SMC migration in vitro via u-PA and MMP-dependent mechanisms. Moreover, u-PA gene deletion results in blunting of pressure-induced SMC migration despite the endogenous upregulation of metalloproteinase. Modulation of u-PA expression by pressure may thus represent an important mechanism whereby hemodynamic forces regulate smooth muscle cell migration. 相似文献
65.
Metz-Lutz MN Kleitz C de Saint Martin A Massa R Hirsch E Marescaux C 《Developmental neuroscience》1999,21(3-5):182-190
Benign focal epilepsy of childhood (BFEC) is the most common form of epilepsy, in children from 3 to 12 years. Its prognosis is always favourable as far as the epilepsy is concerned. Nevertheless, recent clinical data suggest that children affected by BFEC are more likely to show learning difficulties and behavioural disturbances than their peers. We report here the preliminary findings of a prospective study of 22 children affected with BFEC. Electroclinical and neuropsychological changes observed during the first 18 months of the follow-up strengthen the conclusion of recent neuropsychological studies stressing the correlation between epilepsy and cognitive performances. The cognitive deficits affecting mainly non-verbal functions were significantly correlated with the frequency of seizures and spike-wave discharges and to the lateralization of the epileptic focus in the right hemisphere, whereas frontal functions like attention control, response organization and fine motor speed, were impaired in the presence of active BFEC independently of the lateralization of the epileptic focus. Our results indicate that maturing cognitive functions subserved by a cortical area distant from the epileptic focus are susceptible to interference with epilepsy. Copyright Copyright 1999 S. Karger AG, Basel 相似文献
66.
PURPOSETo describe the radiologic appearance of hydroxyapatite cement (HAC), which, when mixed with liquid, forms a paste that can be contoured to osseous defects and, over time, becomes "osseointegrated" (native bone grows into the pores of the HAC and forms a strong chemical bond with the substance).METHODSBetween March 1992 and June 1993, 24 adults (16 men, eight women) underwent skull base surgery that included reconstruction or closure with HAC. Fourteen patients had HAC placed in the paranasal sinuses or facial bones, and 10 had HAC placed in the mastoid cavity.RESULTSHAC is homogeneously radiopaque on CT scans and plain radiographs. Large amounts (ablating a frontal sinus or mastoid air cells) are readily seen; small amounts are inconspicuous. On MR images, HAC is a signal void. Infected HAC in one patient was surrounded be enhancing soft tissue on MR images, separated from native bone by an irregular radiolucent cleft on CT scans.CONCLUSIONSHAC is a valuable addition to the surgical armamentarium for the repair of skull base defects. More experience will determine the time course for normal osseointegration, as well as the typical appearance of infection. 相似文献
67.
68.
In various series reported in the literature on the operative management of severe head injuries with compound depressed skull fractures and penetrating wounds of the brain, the rates of infection differ from 1 to 17%. In this paper the operative experience with 22 cases of penetrating head injuries is discussed. In conventional operative therapy, depressed skull fracture and lacerated dura were covered by "Sulmycin Implant" containing Gentamycin as a helpful bacteriological barrier. 18 patients survived, 7 patients had severe neurological defects, 5 patients had mild neurological deficits and 6 patients recovered completely. There were no signs of suppurative complications in superficial wounds or in the brain. 4 patients died due to their severe brain damage with multiple contusional lesions. Postoperative complications were as follows: one patient suffered extradural and one patient subdural rebleeding. Another patient with a frontal base skull fracture suffered a pneumatocele because the fracture was not correctly covered. The revision was done successfully using the "Sulmycin Implant". Presently, however, the intradural use of "Sulmycin Implant" is not recommended without further testing for the level of gentamycin in the cerebrospinal fluid which is released by the "Sulmycin Implant". 相似文献
69.
70.
Vila M Périer C Féger J Yelnik J Faucheux B Ruberg M Raisman-Vozari R Agid Y Hirsch EC 《The European journal of neuroscience》2000,12(1):337-344
Cellular expression of cytochrome oxidase subunit I (COI) mRNA has recently been used as a metabolic marker for neuronal activity to study the functional changes in the subthalamic nucleus (STN) in parkinsonism. The previous experimental studies have been performed when the pathological state was stabilized at a maximal level. In order to determine the evolution of changes in neuronal activity in the STN after nigrostriatal denervation, we analysed by in situ hybridization the cellular expression of COI mRNA in the subthalamic neurons at different times, from 6 h to 14 days, after unilateral intranigral microinjection of 6-hydroxydopamine (6-OHDA) in rats. In parallel, the time-dependent changes of the unit neuronal activity of subthalamic neurons have been recorded. Levels of COI mRNA increased by 41% in subthalamic neurons from 24 h after 6-OHDA intoxication, to 14 days (+26%). Similarly, electrical activity started to increase slightly 24 h after lesion (+20%) and remained significantly higher at 14 days after the lesion (+189%). Changes in neuronal mean discharge rate were associated with changes in the pattern of spiking activity, from a regular firing pattern to an irregular one with a high bursting activity. These results show that: (i) the hyperactivity of the STN represents a very early phenomenon in the physiopathology of parkinsonian syndromes; and (ii) that changes in COI mRNA expression slightly precede changes in electrical neuronal activity. 相似文献