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991.
This multisite study was conducted to compare the efficacy and tolerability of combination treatment with clozapine plus aripiprazole versus combination treatment with clozapine plus haloperidol in patients with schizophrenia who do not have an optimal response to clozapine. Patients continued to take clozapine and were randomly assigned to receive daily augmentation with aripiprazole or haloperidol. Physicians prescribed the allocated treatments according to usual clinical care. Withdrawal from allocated treatment within 3 months was the primary outcome. Secondary outcomes included severity of symptoms on the Brief Psychiatric Rating Scale and antipsychotic subjective tolerability on the Liverpool University Neuroleptic Side Effect Rating Scale. A total of 106 patients with schizophrenia were randomly assigned to treatment. After 3 months, we found no difference in the proportion of patients who discontinued treatment between the aripiprazole and haloperidol groups (13.2% vs 15.1%, P = 0.780). The 3-month change of the Brief Psychiatric Rating Scale total score was similar in the aripiprazole and haloperidol groups (-5.9 vs -4.4 points, P = 0.523), whereas the 3-month decrease of the Liverpool University Neuroleptic Side Effect Rating Scale total score was significantly higher in the aripiprazole group than in the haloperidol group (-7.4 vs -2.0 points, P = 0.006). These results suggest that augmentation of clozapine with aripiprazole offers no benefit with regard to treatment withdrawal and overall symptoms in schizophrenia compared with augmentation with haloperidol. However, an advantage in the perception of adverse effects with aripiprazole treatment may be meaningful for patients.  相似文献   
992.
993.
The leather industry is a major producer of wastewaters and releases large quantities of many different chemical agents used in hide processing into the environment. Since the central nervous system is sensitive to many different contaminants, our aim was to investigate the neurobehavioral effects of exposure of mice to tannery effluents using animal models of depression and anxiety, namely forced swim and elevated plus-maze. In order to propose a clean technology for the treatment of this effluent, we also investigated the exposure of mice to effluents treated by photoelectrooxidation process (PEO). Adult male Swiss albino mice (CF1 strain) were given free access to water bottles containing an effluent treated by a tannery (non-PEO) or PEO-treated tannery wastewater (0.1 and 1% in drinking water). Exposure to tannery wastewater induced behavioural changes in the mice in elevated plus-maze. Exposure to non-PEO 1% decreased the percentage of time spent in the open arms, indicating anxiety-like behaviour. Exposure to tannery wastewater did not alter immobility time in the forced swim test, suggesting that tannery effluents did not induce depression-like behaviour in the mice. These behavioural data suggest that non-PEO tannery effluent has an anxiogenic effect, whereas PEO-treated tannery effluents do not alter anxiety levels.  相似文献   
994.
In light of the adverse side-effects of opioids, cannabinoid receptor agonists may provide an effective alternative for the treatment of cancer pain. This study examined the potency and efficacy of synthetic CB1 and CB2 receptor agonists in a murine model of tumor pain. Intraplantar injection of the CB1 receptor agonist arachidonylcyclopropylamide (ED(50) of 18.4 μg) reduced tumor-related mechanical hyperalgesia by activation of peripheral CB1 but not CB2 receptors. Similar injection of the CB2 receptor agonist AM1241 (ED50 of 19.5 μg) reduced mechanical hyperalgesia by activation of peripheral CB2 but not CB1 receptors. Both agonists had an efficacy comparable with that of morphine (intraplantar), but their analgesic effects were independent of opioid receptors. Isobolographic analysis of the coinjection of arachidonylcyclopropylamide and AM1241 determined that the CB1 and CB2 receptor agonists interacted synergistically to reduce mechanical hyperalgesia in the tumor-bearing paw. These data extend our previous findings that the peripheral cannabinoid receptors are a promising target for the management of cancer pain and mixed cannabinoid receptor agonists may have a therapeutic advantage over selective agonists.  相似文献   
995.
Idiosyncratic adverse drug reactions (IADRs) in humans can result in a broad range of clinically significant toxicities leading to attrition during drug development as well as postlicensing withdrawal or labeling. IADRs arise from both drug and patient related mechanisms and risk factors. Drug related risk factors, resulting from parent compound or metabolites, may involve multiple contributory mechanisms including organelle toxicity, effects related to compound disposition, and/or immune activation. In the current study, we evaluate an in vitro approach, which explored both cellular effects and covalent binding (CVB) to assess IADR risks for drug candidates using 36 drugs which caused different patterns and severities of IADRs in humans. The cellular effects were tested in an in vitro Panel of five assays which quantified (1) toxicity to THLE cells (SV40 T-antigen-immortalized human liver epithelial cells), which do not express P450s, (2) toxicity to a THLE cell line which selectively expresses P450 3A4, (3) cytotoxicity in HepG2 cells in glucose and galactose media, which is indicative of mitochondrial injury, (4) inhibition of the human bile salt export pump, BSEP, and (5) inhibition of the rat multidrug resistance associated protein 2, Mrp2. In addition, the CVB Burden was estimated by determining the CVB of radiolabeled compound to human hepatocytes and factoring in both the maximum prescribed daily dose and the fraction of metabolism leading to CVB. Combining the aggregated results from the in vitro Panel assays with the CVB Burden data discriminated, with high specificity (78%) and sensitivity (100%), between 27 drugs, which had severe or marked IADR concern, and 9 drugs, which had low IADR concern, we propose that this integrated approach has the potential to enable selection of drug candidates with reduced propensity to cause IADRs in humans.  相似文献   
996.
997.
Ovarian hormone loss contributes to cognitive decline in postmenopausal women. Studies have demonstrated a positive role of the level of the element selenium in cognitive performance. The present study investigated the effects of the synthetic organoselenium compound diphenyl diselenide (PhSe)? on cognitive functions in ovariectomized rats. Ninety-day-old female Wistar rats were subjected to ovariectomy (OVX) or Sham operation. One week after surgery, rats were orally treated with (PhSe)? (5 mg/kg, per oral route) or vehicle once a day for 30 days. Next, the rats were evaluated in behavioral tests [Morris water maze (MWM) and open-field tests] and biochemical [cerebral acetylcholinesterase (AChE)] analyses were carried out. In MWM probe trial, (PhSe)? decreased the latency to reach the platform location and increased the number of crossings over the platform location, protecting against cognitive impairment induced by OVX. Furthermore, (PhSe)? prevented the stimulation of AChE activity caused by OVX. In conclusion, the present study showed a cognition-enhancing effect of (PhSe)? treatment for 30 days in ovariectomized rats in the MWM test, which could be related to its ability to prevent the stimulation of AChE activity caused by OVX in rats. These findings suggest that (PhSe)? might have a promising role in preventing the cognitive decline related to menopause.  相似文献   
998.
Introduction and Aims. Current alcohol guidelines in Australia recommend minimising alcohol consumption, especially among minors. This study investigated (i) the extent to which children and the general population are exposed to television advertisements that endorse alcohol consumption and (ii) the themes used in these advertisements. Design and Methods. A content analysis was conducted on alcohol advertisements aired over two months in major Australian cities. The advertisements were coded according to the products that were promoted, the themes that were employed, and the time of exposure. Advertising placement expenditure was also captured. Results. In total, 2810 alcohol advertisements were aired, representing one in 10 beverage advertisements. Advertisement placement expenditure for alcohol products in the five cities over the two months was $15.8 million. Around half of all alcohol advertisements appeared during children's popular viewing times. The most common themes used were humour, friendship/mateship and value for money. Discussion and Conclusions. Children and adults are regularly exposed to advertisements that depict alcohol consumption as fun, social and inexpensive. Such messages may reinforce existing alcohol-related cultural norms that prevent many Australians from meeting current intake guidelines.[Pettigrew S, Roberts M, Pescud M, Chapman K, Quester P, Miller C. The extent and nature of alcohol advertising on Australian television. Drug Alcohol Rev 2012;31:797-802].  相似文献   
999.
Ahnak1 is a giant, ubiquitously expressed, plasma membrane support protein whose function in skeletal muscle is largely unknown. Therefore, we investigated whether ahnak would be influenced by alterations of the sarcolemma exemplified by dysferlin mutations known to render the sarcolemma vulnerable or by mutations in calpain3, a protease known to cleave ahnak. Human muscle biopsy specimens obtained from patients with limb girdle muscular dystrophy (LGMD) caused by mutations in dysferlin (LGMD2B) and calpain3 (LGMD2A) were investigated for ahnak expression and localization. We found that ahnak1 has lost its sarcolemmal localization in LGMD2B but not in LGMD2A. Instead ahnak1 appeared in muscle connective tissue surrounding the extracellular site of the muscle fiber in both muscular dystrophies. The entire giant ahnak1 molecule was present outside the muscle fiber and did only partially colocalize with CD45-positive immune cell infiltration and the extracelluar matrix proteins fibronectin and collagenVI. Further, vesicles shedded in response to Ca(2+) by primary human myotubes were purified and their protein content was analysed. Ahnak1 was prominently present in these vesicles. Electron microscopy revealed a homogenous population of vesicles with a diameter of about 150?nm. This is the first study demonstrating vesicle release from human myotubes that may be one mechanism underlying abnormally localized ahnak1. Taken together, our results define ahnak1 in muscle connective tissue as a novel feature of two genetically distinct muscular dystrophies that might contribute to disease pathology.  相似文献   
1000.
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