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41.

A substantial number of epileptic patients are resistant to the current medication thus necessitating the search for alternative therapies for intractable forms of the disease. Previous studies demonstrated the acute anticonvulsant properties of the methanol extract of the stem bark of Psychotria camptopus (MEPC) in rats. This study investigated the effects of MEPC on pentylenetetrazole-kindled Wistar rats. Kindling was induced by intraperitoneal injection of pentylenetetrazole (37.5 mg/kg) on every alternate day, 1 h after each daily oral pretreatment of rats (8?≤?n?≤?10) with MEPC (40, 80 and 120 mg/kg), vehicle or diazepam (3 mg/kg) for 43 days. The kindling development was monitored based on seizure episodes and severity. Rats’ brains were collected on day 43 for the determination of oxidative stress parameters. The histomorphological features and neuronal cell viability of the prefrontal cortex (PFC) and hippocampus were also assessed using H&E and Cresyl violet stains. Chronic administration of pentylenetetrazole time-dependently decreased the latency to myoclonic and generalized seizures, and increased seizure scores and the number of kindled rats. MEPC and diazepam significantly increased the latencies to myoclonic jerks and generalized tonic-clonic seizures. These substances also reduced seizure score and the number of rats with PTZ-kindling. MEPC improved glutathione status and decreased lipid peroxidation in the brains of kindled rats. MEPC also exhibited neuroprotection against pentylenetetrazole-induced hippocampal and PFC neuronal damages. These results suggest that P. camptopus has antiepileptogenic activity, which might be related to the augmentation of antioxidant and neuroprotective defense mechanisms, and further confirm its usefulness in the management of epilepsy.

  相似文献   
42.
Global Initiative for Chronic Obstructive Lung Diseases (GOLD)   总被引:2,自引:0,他引:2  
Chronic Obstructive Pulmonary Disease (COPD) is a major cause of chronic morbidity and mortality throughout the world. In an effort to increase awareness of COPD and to develop consensus on scientific evidence for management and prevention of this disease, the Global Initiative for Chronic Obstructive Lung Disease (GOLD) program was formed. A summary of the GOLD program is presented along with information about GOLD documents.  相似文献   
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Two thirds of patients suffering from a major depressive episode (MDE) do not reach a complete response with antidepressant drugs. This lack of response is due to several factors, including genetic determinants. Since major depressive disorder is associated with inflammatory and oxidative stress abnormalities, the metabolism of superoxide anions might be involved in non‐response to antidepressant drugs. Superoxide anions are metabolized by manganese‐dependent superoxide dismutase (SOD2) in the mitochondria. A functional genetic polymorphism (SOD2, rs4880), responsible of a 40% reduction in enzyme activity, is associated with anti‐inflammatory response of rosuvastatin. We investigated the association of ala‐allele of SOD2 rs4880 and both antidepressant efficacy and inflammatory parameters in patients treated for a MDE with antidepressant drugs. The Hamilton Depression Rating Scale (HDRS) score and levels of plasma CRP and inflammatory cytokines were assessed at baseline, one month (M1), 3 months (M3) and 6 months (M6) after antidepressant treatment. They were compared according to SOD2 genetic polymorphism. Of the 484 patients studied, 361 (74.6%) carried the ala‐allele (Ala group), 123 (25.4%) of them had Val/Val genotype (Val/Val group). No significant difference was observed between the Ala and Val/Val groups neither for baseline clinical characteristics, nor for HDRS scores, response/remission rates, plasma CRP and cytokine levels throughout the study. The rs4880 SOD2 genetic polymorphism was not associated with the clinical response and cytokines levels after antidepressant treatment. These data suggest that SOD2 is not a major genetic determinant of antidepressant response. Other genes of the oxidative stress pathways should be explored in further studies.  相似文献   
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Objective:

The aim of this study was to evaluate the potential of simultaneously modulated accelerated radiation therapy (SMART) to reduce the incidence of severe acute oesophagitis in the treatment of unresectable locally advanced non-small-cell lung cancer (LANSCLC).

Methods:

21 patients were treated with SMART and concomitant platinum-based chemotherapy. The prescribed doses were limited to 54 Gy at 1.8 Gy per day to the zones of presumed microscopic extent while simultaneously maintaining doses of 66 Gy at 2.2 Gy per day to the macroscopic disease. The whole treatment was delivered over 30 fractions and 6 weeks. Dosimetric parameters of SMART and the standard technique of irradiation [intensity-modulated radiation therapy (IMRT)] were compared. Acute toxicity was prospectively recorded.

Results:

The highest grade of oesophagitis was 62% (13 patients) grade 1, 33% (7 patients) grade 2 and 5% (1 patient) grade 3. Three (14%) patients experienced acute grade 2 pneumonitis. There was no grade 4 oesophageal or pulmonary toxicity. Doses to the organs at risk were significantly reduced in SMART compared with IMRT [oesophagus: V50Gy, 28.5 Gy vs 39.9 Gy (p = 0.003); V60Gy, 7.1 Gy vs 30.7 Gy (p = 0.003); lung: V20Gy, 27.4 Gy vs 30.1 Gy (p = 0,002); heart: V40Gy, 7.3 Gy vs 10.7 Gy (p= 0.006); spine: Dmax, 42.4 Gy vs 46.4 Gy (p = 0.003)]. With a median follow-up of 18 months (6–33 months), the 1-year local control rate was 70% and the disease-free survival rate was 47%.

Conclusion:

SMART reduces the incidence of severe oesophagitis and improves the whole dosimetric predictors of toxicity for the lung, heart and spine.

Advances in knowledge:

Our study shows that SMART optimizes the therapeutic ratio in the treatment of LANSCLC, opening a window for dose intensification.  相似文献   
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