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81.
The aim of this retrospective case series analysis was to identify the predictors of postoperative depression (PostOp‐D) in a sample of 248 subjects with focal drug‐resistant focal epilepsy. The presence or absence of PostOp‐D during a 12‐month follow‐up period was the outcome variable. Demographic, neurologic, psychiatric characteristics, and antiepileptic therapy were the explanatory variables. After preliminary bivariate analysis, a multivariate logistic regression model was fitted to identify variables associated with PostOp‐D. Sixty‐seven patients (27%) experienced PostOp‐D. At multivariate analysis, lifetime depression, age at surgery, and levetiracetam (LEV) are positive predictors of PostOp‐D; carbamazepine (CBZ) and anxiety disorders are protective factors. LEV increases the risk for PostOp‐D by about half; the relative risk (RR) is 1.48. Conversely, CBZ decreases the risk for PostOp‐D by about half (RR 0.59). Our results suggest that careful psychiatric evaluation and follow‐up should be recommended for subjects at risk. It is advisable to treat patients with depression before surgery. Antiepileptic drugs should be selected carefully when patients present with not modifiable risk factors, such as positive personal history for depression.  相似文献   
82.
Two distinct forms of synaptic plasticity have been described at corticostriatal synapses: long-term depression (LTD) and long-term potentiation (LTP). Both these enduring changes in the efficacy of excitatory neurotransmission in the striatum have a major impact on the physiological activity of the basal ganglia and are triggered by the stimulation of complex and independent cascades of intracellular second messenger systems. Along with the massive glutamatergic inputs originating from the cortex, striatal neurons receive a myriad of other synaptic contacts arising from different sources. In particular, while the nigrostriatal pathway provides this brain area with dopamine (DA), intrinsic circuits are the main source of acetylcholine (ACh) and nitric oxide (NO). The three neurotransmitter systems interact with each other to determine whether corticostriatal LTP or LTD is triggered in response to repetitive synaptic stimulation. Two distinct subtypes of striatal interneurons produce ACh and NO in the striatum. These interneurons are activated by the cortex during the induction phase of striatal plasticity, and stimulate, in turn, the intracellular changes in projection neurons required for LTD or LTP. Interneurons, therefore, exert a feedforward control of the excitability of striatal projection neurons by ensuring the coordinate expression of two alternative forms of synaptic plasticity at the same type of excitatory synapse. The integrative action exerted by striatal projection neurons on the converging information arising from the cortex, nigral DA neurons, and from ACh- and NO-producing interneurons dictates the final output of the striatum to the other structures of the basal ganglia.  相似文献   
83.
DISCUSSION: The leptomeningeal dissemination (LMD) of low-grade gliomas (LGGs) is reported in clinical neuro-oncology practice more and more frequently. It is estimated that 5% of all childhood LGGs present LMD at diagnosis and 7-10% at the time of progression. LMD has been reported in association with almost all the known subtypes of LGGs. Furthermore, "unusual " LGGs can be encountered among slow-growing brain neoplasm capable of LMD, which cannot comfortably be included in the present WHO brain tumour classification. The biological, genetic and clinical characteristics that seem to favour LMD are far from being understood. Similarly, the clinical profile of those children with disseminated LGGs has not yet been firmly established. Young, non-neurofibromatosis type 1 boys with large hypothalamic-chiasmatic pilocytic astrocytomas seem to be at increased risk of LMD. The neuroradiological appearance of LMD in childhood LGGs is similar to that observed in malignant tumours, except for those cases characterised by multiple superficial non-enhancing cystic lesions, which seem to be almost exclusively associated with a type of slow-growing not yet fully identified brain stem or spinal tumour. No firm guidelines for the treatment of these diseases are yet available, mostly due to the rarity of this condition and the existing uncertainties regarding their natural clinical history. CONCLUSION: The evidence of LMD in children with LGGs does not seem to have a negative impact on patients' long-term outcome.  相似文献   
84.
We have investigated the role of dopaminergic receptors in modulation of basic fibroblast growth factor (FGF-2) expression in rat prefrontal cortex and hippocampus, two brain regions important for cognition. We found that FGF-2 expression is upregulated by quinpirole, a D2 agonist, in prefrontal cortex and to a lesser extent in hippocampus. This modulation was specific for dopamine D2 receptors because no effect was observed when the dopamine D1 and D3 agonists, SKF38393 and 7-OH-DPAT, respectively, were administered. Our findings show that activation of dopaminergic D2 receptors modulates FGF-2 expression in rat prefrontal cortex and hippocampus. Our data highlight the complex modulation of FGF-2 expression in limbic areas pointing to this trophic molecule as a putative target of drugs used against acute and chronic neurodegenerative diseases such as Parkinson's disease.  相似文献   
85.
Purpose:   With the development of intensive care, the survival of extremely low-birthweight (ELBW) infants (<1,000 g) has greatly improved. The aim of our study was to report the incidence of epilepsy after a follow-up of >7 years in a population of ELBW children, born in central and southern Sardinia between 1991 and 2000.
Methods:   We analyzed data of 104 children. All infants had had serial cranial ultrasound echography (CUE) in the neonatal period and some also had magnetic resonance imaging (MRI). At last follow-up we evaluated the occurrence of epilepsy through a review of clinical charts and a structured telephone interview.
Results:   In 11 (10.6%) of 104 of children we observed febrile seizures (FS). Epilepsy occurred in 9 (8.6%) of 104 ELBW children, and in these patients a frequent positive family history for epilepsy and/or FS was present. In four epilepsy patients CUE was highly pathologic, showing intraventricular hemorrhage (IVH) of grade IV and in two mildly abnormal (IVH of grade I–II). In three additional children with normal neonatal ultrasound scan, a later magnetic resonance imaging (MRI) study revealed lesions related to neonatal insult.
Discussion:   In our ELBW population, epilepsy had an incidence clearly superior to that expected in infancy (8.6% vs. 0.6–0.8% ) . A frequent positive familiar history for epilepsy and/or FS suggests that a genetic predisposition may also play a role. Subjects with highly abnormal CUE are a subgroup with high risk for seizures; however, epilepsy can occur even with normal CUE.  相似文献   
86.
We have performed a translational phase II trial testing an original immunotherapy schedule based on the monthly subcutaneous (s.c.) administration of hrGM-CSF (days 1 through 5) and very low dose hrIL-2 (days 6 through 15) in 19 patients with metastatic renal cell carcinoma. Bone pain, first dose reaction to GM-CSF, asthenia and fever were the most common side effects. A partial response, and a disease stabilization were respectively observed in 4 and 11 cases, with a rate of objective response and a disease control rate respectively of 21% and 79%. We recorded a time to progression of 9 months and a 2- and 3-year survival respectively of 42% (8/19 patients) and 26% (5/19 patients). Our results suggest that this GM-CSF/hrIL-2 combination is active and well tolerated in patients with renal cell carcinoma and deserves to be investigated in larger comparative trials.  相似文献   
87.
BACKGROUND: Surgical resection is the cornerstone of treatment for patients with hepatoblastoma (HB). The Society of Pediatric Oncology Liver Tumor Study Group launched its first prospective trial (SIOPEL-1) with the intention to treat all patients with preoperative chemotherapy and delayed surgical resection. The objective of this article was to assess the assumed surgical advantages of primary chemotherapy. METHODS: Between 1990 and 1994, 154 patients age < 16 years with HB were registered on SIOPEL-1. The pretreatment extent of disease was assessed, and, after undergoing biopsy, patients were treated with cisplatin 80 mg/m(2) intravenously over 24 hours and doxorubicin 60 mg/m(2) intravenously over 48 hours by continuous infusion (PLADO). Generally, tumors were resected after four of a total of six courses of PLADO. RESULTS: One hundred twenty eight patients underwent surgical resection (13 patients underwent primary surgery, and 115 patients underwent delayed surgery after PLADO). A pretreatment surgical biopsy was performed in 96 of 128 patients (75%). Biopsy complications occurred in 7 of 96 patients (7%). Twenty-two patients showed pulmonary metastases at the time of diagnosis, and 7 patients underwent thoracotomy. Operative morbidity and mortality were 18% and 5%, respectively. Complete macroscopic surgical resection was achieved in 106 patients (92%), including 6 patients who underwent orthotopic liver transplantation. The actuarial 5-year event free survival (EFS) rate for all 154 patients in the study was 66%, and the overall survival (OS) rate was 75%. For the 115 patients who were included in the surgical analysis that followed the exact protocol, the EFS and OS rates were 75% and 85%, respectively. CONCLUSIONS: Biopsy is a safe procedure and should be performed routinely. Preoperative chemotherapy seems to make tumor resection easier. Reresection of a positive resection margin does not necessarily have to be performed, because postoperative chemotherapy showed good results. Resection of lung metastases can be curative if there is local control of the primary tumor; however, results showed that the patient's prognosis was worse. Surgical morbidity or mortality rates were not necessarily higher in large multicenter studies. More importantly, countries of lesser economic status also can contribute effectively to these trials.  相似文献   
88.
89.
In the context of a medical surveillance program aimed at preventing cancer risk from exposure to ionizing radiation, we investigated chromosomal damage in peripheral lymphocytes from 37 hospital workers exposed to low levels of ionizing radiation and 37 controls. The micronuleus (MN) assay was used as a biomarker of genetic damage. The influence of confounding factors like smoking status, age and gender was investigated by multiple regression analysis. The results indicated that, overall, MN frequency was higher in exposed workers than in controls, although the difference was not statistically significant. Interestingly, smoking status significantly raised MN frequency among the exposed workers but not among controls. This suggests that smoking can influence chromosomal damage induced in humans by ionizing radiation. Among both exposed workers and controls, MN frequency was found to increase with age. Female gender influenced the increase in MN frequency in the exposed group. Our results suggest that the effect of cigarette smoking should be carefully factored into genetic monitoring studies assessing the risks associated with low level radiation exposure.  相似文献   
90.
Nonspecific X‐linked mental retardation is a nonprogressive, genetically heterogeneous condition that affects cognitive function in the absence of other distinctive clinical manifestations. We report here linkage data on a large Pakistani family affected by a form of X‐linked nonspecific mental retardation. X chromosome genotyping of family members and linkage analysis allowed the identification of a new disease locus, MRX53. The defined critical region spans approximately 15 cM between DXS1210 and DXS1047 in Xq22.2–26. A LOD score value of 3.34 at no recombination was obtained with markers DXS1072 and DXS8081. © 2001 Wiley‐Liss, Inc.  相似文献   
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