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Patients treated for aneurysmal subarachnoid hemorrhage show, in the long-term follow up, an elevated rate of cognitive disturbances that are mainly related to the impact of the initial bleeding: the neurotoxic effects of blood deposition in subarachnoidal spaces may result in a diffuse encephalopathy, but the intrinsic mechanism and the biochemical correlates are not known. In the present study we have evaluated mitochondrial function after experimental induction of subarachnoid hemorrhage. Mitochondrial function was evaluated in four different rat brain areas (frontal cortex, occipital cortex, hippocampus, and brain stem) after experimental isobaric subarachnoid hemorrhage in rats. Subarachnoid hemorrhage was induced by injecting 0.07 mL of arterial autologous blood into the cisterna magna. Intracranial pressure did not significantly increase. The nonsynaptic mitochondrial fraction was isolated from different rat brain areas, and the maximal rate of enzymatic reactions of some key enzymatic activities related to the Krebs cycle [nicotinamide adenine dinucleotide (oxidized form) (NAD+)-isocitrate dehydrogenase, citrate synthase, and succinate dehydrogenase] and of the electron transfer chain (cytochrome oxidase) were evaluated. The nonsynaptic mitochondrial fraction was utilized also to check parameters related to the mitochondrial respiration: state 3, state 4, uncoupled state, respiratory control ratio, and adenosine 5'-diphosphate/oxygen ratio. The biochemical parameters were measured at 1 and 72 hours after the subarachnoidal injection of blood. Subarachnoid hemorrhage did not affect the mitochondrial enzymatic activities both at 1 and 72 hours, while the mitochondrial enzymatic activities parameters were significantly affected: in particular, a significant decrease of respiratory control ratio in all tested brain areas was demonstrated. The increased mitochondrial vulnerability in the delayed phases could be one of the biochemical correlates of post-hemorrhagic encephalopathy.  相似文献   
3.
Abstract Epilepsy in high-grade glioma patients is a major concern, mainly as regards indications to treatment and best choice; toxicities, and pharmocokinetic and pharmacodynamic interactions of drugs. All these generally unsolved problems complicate patients’ quality of life and interfere with the evaluation of response criteria in clinical trials. A prospective, multicentre data collection on 132 adult newly diagnosed, histologically proven glioblastomas from 9 Lombardy hospitals collected in the same database during a one-year period was recently published. From this database we report epidemiological and clinical characteristics in epilepsy-symptomatic (31%) glioblastoma patients vs. the group with other presenting symptoms (69%). We analyse demographic and clinico-radiological features, timing of onset and the course of seizures, and modalities of treatment in the two groups of patients. No statistically significant differences were observed between the two groups as regards age, site of lesion(s), extent of surgery and survival in relation to anticonvulsant treatment status or pharmacokinetic properties of drugs.  相似文献   
4.
Non-Hodgkin's lymphoma of the central nervous system (NHL-CNS) is thought to account for about 1 % of primary brain tumours. Radiation therapy has mainly been applied to treat cerebral lymphoma, but the low cure rate and the lack of enduring response have stimulated the search for alternatives. With the aim of postponing radiotherapy as long as possible, we tested the efficacy of a M-BACOD schedule administered immediately after histological diagnosis in 14 patients. After two M-BACOD courses 10 (71%) patients displayed an objective response (i.e. were apparently tumour-free when examined by CT). In 6 (60%) M-BACOD-responsive patients, radiotherapy was delayed for 5 months (without recurrences after a follow-up ranging from 9 to 18 months). Moreover, in 3 M-BACOD-responsive patients, no recurrence took place (even without radiotherapy) after a follow-up of 6–12 months. We conclude that radiation can be postponed after chemotherapy or delayed until tumor recurrence.This paper was presented at the 3rd Meeting of the European Neurological Society, Lausanne, 27 June–1 July, 1992  相似文献   
5.
Dosage and schedules for the treatment of malignant glial tumors using IFN (interferon) are still uncertain and controversial. In this study we give the preliminary results of treatment in 28 patients with glioblastoma multiforme (GBM). 6 patients were treated with local injection of β-IFN through an Ommaya reservoir; 4 patients with β-IFN followed by systemic chemotherapy (Cisplatin+Etoposide), and 18 patients with chemotherapy only. Two end points were evaluated: 1) Whether or not the patients responded to treatment. 2) Length of Time to Tumor Progression(TTP) after surgery. We found that IFN alone was ineffective. Results were improved when local immunotherapy was associated with systemic chemotherapy. New drugs and investigation of possible pharmacological synergism are needed.  相似文献   
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Hypocretin/orexin signalling varies among sleep–wake behaviours, impacts upon cardiovascular autonomic control and is impaired in patients with narcolepsy with cataplexy (NC). However, evidence concerning disturbed cardiovascular autonomic control in NC patients is contrasting, and limited mainly to waking behaviour. We thus investigated whether control of cardiovascular variability is altered in NC patients during wakefulness preceding sleep, light (1–2) and deep (3–4) stages of non‐rapid eye movement (NREM) sleep and rapid eye movement (REM) sleep. Polysomnographic recordings and finger blood pressure measurements were performed on nine drug‐free male NC patients and nine matched healthy control subjects during spontaneous sleep–wake behaviour in a standardized laboratory environment. Indices of autonomic function were computed based on spontaneous fluctuations of systolic blood pressure (SBP) and heart period (HP). During wakefulness before sleep, NC patients showed significant decreases in indices of vagal HP modulation, cardiac baroreflex sensitivity and amplitude of central autonomic (feed‐forward) cardiac control compared with control subjects. During NREM sleep, the negative correlation between HP and subsequent SBP values was greater in NC patients than in control subjects, suggesting a greater contribution of central autonomic commands to cardiac control. Collectively, these results provide preliminary evidence that autonomic control of cardiac variability by baroreflex and central autonomic (feed‐forward) mechanisms is altered in NC patients during spontaneous sleep–wake behaviour, and particularly during wakefulness before sleep.  相似文献   
8.
The indium-mediated allylation of novel 3-(2-Boc-hydrazono)indolin-2-one derivatives, followed by a palladium-catalysed carboamination reaction, is described to afford unprecedented spirocyclic oxindoles in good yields. The method provides an efficient access to both cis and trans diastereoisomers of highly functionalized compounds, bearing an N-Boc, 5-substituted pyrazolidine ring at the C3-oxindole spiro junction. The versatility of the method is fully demonstrated starting from a series of substituted isatins and employing a variety of aryl halides in the key cyclization step.

The indium-mediated allylation of novel 3-(2-Boc-hydrazono)indolin-2-one derivatives, followed by a palladium-catalysed carboamination reaction, is described to afford unprecedented spirocyclic oxindoles in good yields.  相似文献   
9.
A multicomponent Ugi reaction involving isatin, isocyanide and β-amino acid components has been developed. The reactions proceeded smoothly to give β-lactam-containing 3,3-disubstituted oxindoles in only one step and generally high yields. When chiral, non racemic, β-amino acids were used, products were obtained as enantiomerically pure β-lactams diastereoisomers, whose relative stereochemistry was determined by X-ray analysis. For one compound, a weak antibacterial activity has been preliminarily highlighted.

A multicomponent Ugi reaction involving isatin, isocyanide and β-amino acid components has been developed.  相似文献   
10.
BACKGROUND AND OBJECTIVES: We conducted a longitudinal prospective study to assess the eligibility to blood donation of donors with 'minor' risk factors (i.e. minor surgery, professional exposure, cohabitation with 'high risk' people, occasional use of light drugs) or 'medium' risk factors for human immuno-deficiency virus (HIV) infection (i.e. casual sexual relationship, multiple heterosexual exposure, sexual partnership with subjects at risk, regular use of light drugs). DESIGN AND METHODS: During a 4-year period we administered a psychosocial questionnaire to all donors attending our Center. In addition we determined anti-HIV, anti-hepatitis C virus (HCV), hepatitis B surface antigen (HBsAg) and syphilis serology (TPHA) at entry to the study and at 6-month intervals. RESULTS: Of 25,367 donors, 1,535 (6%) reported medium and 8,761 (34%) minor risk. At enrollment into the study, 4 medium risk donors were anti-HIV positive and there was a significantly higher rate of positivity for TPHA (0.33% vs 0.07%) and anti-HCV (1.17% vs 0.63%) in this group than in donors reporting no risk. No anti-HIV positivity was observed in minor or no risk donors. During a median follow-up of 18 months, none of 24,404 donors undergoing 106,503 visits seroconverted to HIV. The incidences of novel HCV and syphilis infections were almost one log greater in donors at medium risk (3 and 1x10-4/yr, respectively) than in no risk donors (0.4 and 0.1x10-4/yr, respectively). Medium risk donors were more frequently males (Odds Ratio=3.2, 95% confidence interval= 2.8-3.7), aged 26-35 yrs (1.52; 1.3-1.78), single (1.4; 1.2-1.6), divorced (2; 1.4-2.8), freelance workers (1.43; 1.1-1.9) and first-time donors (1.8; 1.6-2.1) than no risk donors. INTERPRETATION AND CONCLUSIONS: The only 4 HIV positive subjects of the cohort were medium risk donors picked up at enrollment. No HIV seroconversion was observed during the study. On the basis of this study we will continue to defer 'medium' risk donors.  相似文献   
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