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1.
Migraine is considered to be a functional neurological disorder. In classical migraine (headache associated with prodromal visual field disturbances) and migraine accompagnée (headache associated with transient neurological symptoms), disturbances of cerebral blood flow and amine metabolism are thought to be pathogenetic factors. However, conventional methods of neuroimaging (CAT, NMR) usually do not yield any pathological findings in patients. Since 123I-iodoamphetamine (123I-IMP) crosses the intact blood brain barrier, 123I-IMP-SPECT is used for the assessment of cerebral perfusion in various neurological diseases, including functional disorders. 123I-IMP-SPECT was performed on 5 patients with classical migraine and 18 patients with migraine accompagnée. At the time of investigation, all patients were symptom-free. Cerebral blood flow was decreased in all patients with migraine accompagnée, and often corresponded to the site of headache as well as to the topography of transient neurological symptoms. This reduction was most obvious in a patient with persisting neurological symptoms. Most patients with classical migraine, however, did not show any alteration of cerebral perfusion. It appears that migraine--and in particular migraine accompagnée--is characterized by a permanent alteration not only of cerebral blood flow but also of neuronal activity. Migraine attacks may occur in connection with exacerbations of preexisting metabolic alterations.  相似文献   
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We have examined the chromosomal effects of heating asynchronously growing Chinese hamster ovary (CHO K1) cells in the presence of actinomycin D or cycloheximide. Actinomycin D was found to strongly potentiate the chromosome damaging effects of heat shock, an effect correlated with a strong nonadditive reduction in cell survival. In contrast, cycloheximide treatment reduced heat shock induced chromosome damage and resulted in a significant nonadditive increase in cell survival following heat shock. The different effects of these two inhibitors on chromosomal damage and cell survival are correlated in part with their effects on the rate of DNA synthesis during heat shock. The results suggest that an important aspect of the interaction of heat and metabolic inhibitors involves changes in cell cycle phase distribution of and/or progression through the S phase of the cell cycle induced by drug treatment prior to and during heat shock. The data indicate that the protective effect of cycloheximide in heat shocked cells may involve altered cell cycle progression and/or phase distribution of cells during hyperthermia.  相似文献   
4.
LIM kinase 1 (LIMK1) controls important cellular functions such as morphogenesis, cell motility, tumor cell metastasis, development of neuronal projections, and growth cone actin dynamics. We have investigated the role of the RING finger protein Rnf6 during neuronal development and detected high Rnf6 protein levels in developing axonal projections of motor and DRG neurons during mouse embryogenesis as well as cultured hippocampal neurons. RNAi-mediated knock-down experiments in primary hippocampal neurons identified Rnf6 as a regulator of axon outgrowth. Consistent with a role in axonal growth, we found that Rnf6 binds to, polyubiquitinates, and targets LIMK1 for proteasomal degradation in growth cones of primary hippocampal neurons. Rnf6 is functionally linked to LIMK1 during the development of axons, as the changes in axon outgrowth induced by up- or down-regulation of Rnf6 levels can be restored by modulation of LIMK1 expression. Thus, these results assign a specific role for Rnf6 in the control of cellular LIMK1 concentrations and indicate a new function for the ubiquitin/proteasome system in regulating local growth cone actin dynamics.  相似文献   
5.
Multiple endocrine neoplasia: how many syndromes?   总被引:1,自引:0,他引:1  
The phrase multiple endocrine neoplasia (MEN) generally denotes an association of tumors so specific as to constitute a syndrome. Three well-recognized such syndromes exist. All are autosomal dominant traits and all have been tentatively mapped to specific chromosomes. Other purported endocrine tumor syndromes have been suggested either as new entities or as subtypes of the existing MEN syndromes. The evidence in favor of these contentions is examined critically. Only one "new" association, that of pheochromocytomas and islet cell tumors, seems reasonable, and even in this setting, some relatives have had manifestations of von Hippel-Lindau syndrome. There is no compelling reason why such conditions as von Hippel-Lindau syndrome, peripheral neurofibromatosis, McCune-Albright syndrome, and others should be reclassified as MEN syndromes, although awareness of their collective endocrine abnormalities is clinically important.  相似文献   
6.
The influence of synthetic bradykinin (BK) on disturbed protein and carbohydrate metabolism was studied in chemical and manifest maturity-onset diabetics, in surgical patients and in alloxan diabetic rats. BK,mixed with insulin and injected subcutaneously twice daily in alloxan diabetic rats lowered the morning blood glucose concentration in a dose-dependent way, whereas in a control group treated with insulin only no decrease was seen. Accelerated local blood flow or enhanced vascular permeability as a cause of increased glucose uptake could be ruled out by control experiments using papaverine and eledoisin. Better metabolic control in the BK/insulin-treated group was also indicated by lower arterial levels of free fatty acids and of -hydroxybutyrate, normalized hepatic glycogen content and better growth of body weight. In healthy man an intravenous infusion of BK (80 g/h) did not influence normal fasting blood glucose concentrations, whereas elevated glucose levels in maturity-onset diabetics were continuously reduced within 100 min by 12.2±1.4%. A comparable diabetic group receiving saline alone showed no spontaneous drop of blood glucose concentration. An improvement of pathological carbohydrate metabolism by infusion of BK i.v. could also be demonstrated using the intravenous glucose tolerance test in chemical and manifest maturity-onset diabetics and in surgical patients: in all groupsk values of the glucose tolerance test were significantly increased by BK. This effect was neither due to stimulated insulin release nor to changed glucose pool or to increased renal glucose loss, which was even reduced by BK. Interestingly, normalk values in healthy volunteers were not further improved by BK. A stimulated protein breakdown, which occurs after surgery due to peripheral insulin resistance, can also be restricted by intravenous infusion of BK: in surgical patients urinary nitrogen excretion was reduced by 50% during infusion of BK and was accelerated again after cessation of the infusion. These results indicate that BK can improve the efficacy of exogenous insulin in insulin-deficient animals and depressed insulin sensitivity in maturity-onset diabetics and surgical patients.  相似文献   
7.
The suspicion of prenatal meconium ileus syndrome was raised in a pregnancy in a family with no history of cystic fibrosis because of significantly higher maternal serum alpha-fetoprotein in the 16th and 19th week of gestation, dispersed areas with increased echogenity in the fetal abdomen, slight fetal ascites in the 24th-25th weeks of gestation, decreased amniotic fluid gamma-glutamyltranspeptidase (GGT) activity and alpha-fetoprotein level in the 25th-26th weeks, and normal 46,XY karotype of the fetus. The detection of a homozygous deltaF508 cystic fibrosis transmembrane regulator (CFTR) gene mutation, by means of PCR from a small amount of white blood cells and urine sediment cells, substantiated the diagnosis of cystic fibrosis in a prematurely delivered boy in the 28th week of gestation. The repeated sweat test was unsuccessful. The autopsy examination confirmed the diagnosis of cystic fibrosis. Fetal meconium ileus syndrome was complicated by peritonitis and by formation of a meconium pseudocyst. Direct PCR typing improves postnatal diagnostic possibilities in the early neonatal period in prematurely delivered babies when the sweat test is difficult to perform.  相似文献   
8.
Magnetic resonance angiography (MRA) of the abdominal aorta was performed in 36 patients using the "bright-blood" technique on the basis of a series of flow-compensated breath-hold 2 D-GE pulse sequences. Diverse diseases included complete occlusion, stenosis, atherosclerotic or dissecting aneurysm and renal artery stenosis. Coronal and axial projection angiograms [maximum intensity projection (MIP) algorithm] and individual GE images were compared with DSA and contrast-enhanced computed tomography (CT). Our data showed a good correlation of MR and digital subtraction arteriography (DSA) or CT resp. in all cases, when both rotating MIP angiograms and individual GE images were analyzed. Thus, MR is suggested to be a useful noninvasive diagnostic method for the abdominal aorta, particularly in preoperative staging of aneurysms, aortic occlusive disease, and stenosis of the proximal main renal artery. Drawbacks of the method are a signal loss in slow or turbulent flow conditions, and unsatisfactory spatial resolution in small vessels.  相似文献   
9.
Further experience with seromuscular colocystoplasty lined with urothelium   总被引:1,自引:0,他引:1  
PURPOSE: We report our continuing experience with seromuscular colocystoplasty lined with urothelium. This procedure is designed to preserve the urothelium and potentially decrease the incidence of complications associated with standard bladder augmentation. MATERIALS AND METHODS: We retrospectively reviewed the charts of 32 patients who underwent seromuscular colocystoplasty lined with urothelium between April 1994 and July 1999. Data were collected on patient demographics, surgical indications, previous and adjunctive surgical procedures, preoperative and postoperative urinary continence, upper urinary tract changes, urodynamic parameters, surgical complications and histological findings. RESULTS: Mean patient age at surgery plus or minus standard deviation was 11.1 +/- 4.8 years. Mean followup was 1.6 +/- 1 years. A mean of 1.5 +/- 0.9 years postoperatively urodynamic studies available in 28 cases showed that total and safe bladder capacity increased by 1.8 and 2.4-fold, respectively. Continence was achieved in 71% of patients after the initial procedure, increasing to 81% after secondary procedures. Hourglass deformity developed in 7 cases (22%), augmentation failed in 4 (12.5%) and there were bladder calculi in 2 (6%). New onset or increased hydronephrosis and reflux were present in 6 of 62 (10%) and 9 of 60 (15%) evaluated renal units, respectively. Of the 7 interpretable biopsies 5 revealed various degrees of repeat colonic mucosal growth. There was no bladder perforation or metabolic abnormalities, and mucous production was not clinically significant. CONCLUSIONS: Seromuscular colocystoplasty lined with urothelium is a viable alternative to standard bladder augmentation. The 2 procedures have a similar overall complication rate. Comparatively there appears to be a low incidence of bladder calculi, mucous production has not been clinically significant, metabolic disturbances have not developed and perforation has not occurred during short-term followup. We are enthusiastic about this technique and continue to apply it in select patients.  相似文献   
10.
Reflex sympathetic dystrophy, also known as complex regional pain syndrome (CRPS), has recently been shown to be associated with autoantibodies against β2‐adrenergic and muscarinic M2 receptors. In addition to pain and sudomotor/vasomotor symptoms, dysautonomia is also observed in a subset of CRPS patients. Despite its severity, there are few effective therapies for CRPS described to date. We report a case of a 14‐year‐old girl with CRPS of her right leg and dysautonomia (gastroparesis, postural tachycardia) refractory to multiple therapies, successfully treated with therapeutic plasma exchange (TPE) with albumin replacement. The patient, who has serum anti β2‐adrenergic and muscarinic M2 receptor autoantibodies in addition to nicotinic acetylcholine receptor ganglionic autoantibodies, underwent an initial course of five TPEs over a 2‐week period. She demonstrated a clinical response to TPE as manifested by a rapid improvement in her fatigue and gastroparesis, with a gradual yet significant improvement in her leg pain and sudomotor/vasomotor flares. Following the loading procedures, the patient was treated with rituximab. She continues to require periodic TPE to maintain a remission, with additional immunosuppression being considered long term. Although further studies are needed, TPE (in combination with immunosuppression) may be an appropriate therapy for CRPS patients with detectable autoantibodies, as it is for better characterized diseases with autoantibodies against neuronal surface receptors such as myasthenia gravis or Lambert Eaton myasthenic syndrome. J. Clin. Apheresis 31:368–374, 2016. © 2015 Wiley Periodicals, Inc.  相似文献   
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