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1.
Yossi Gilgun-Sherki Yael Barhum Daphne Atlas Eldad Melamed Daniel Offen 《Journal of molecular neuroscience : MN》1996,27(1):125-135
Accumulating data from experimental studies indicate that oxidative stress has a major role in the pathogenesis of multiple
sclerosis (MS). It has been suggested that local production of reactive oxygen species, probably by macrophages, mediates
axonal damage in both MS patients and the mouse model experimental autoimmune encephalomyelitis (EAE). We have shown previously
that our novel brain-penetrating antioxidant, N-acetylcysteine amide (AD4), reduces the clinical and pathological symptoms, including inflammation and axonal damage in myelin
oligodendrocyte glycoprotein (MOG)-induced chronic EAE in mice. The aim of this study was to examine the molecular mechanism
by which AD4 exerts protection in MOG-induced EAE mice. Therefore, we analyzed gene-expression profile in the spinal cords
of MOG-induced chronic EAE mice and compared them with MOG-induced mice treated with AD4, using a cDNA microarray. We found
that MOG treatment up-regulated genes encoding growth factors, cytokines, death receptors, proteases, and myelin structure
proteins, whereas MOG- and AD4-treated mice demonstrated gene expression profiles similar to that seen in na?ve healthy mice.
In conclusion, our study shows that chronic AD4 administration suppresses the induction of various pathological pathways that
play a role in EAE and probably in MS. 相似文献
2.
建立了毛细管气相色谱法测定乙酸奥曲肽中有机溶剂乙醚、甲醇、二氯甲烷、N,N-二甲基甲酰胺的含量.用HP-Innowax毛细管柱,程序升温的方法.各组分的线性范围分别为25~300、25~300、15~180和25~300μg/ml(r均大于0.999).平均回收率分别为99.7%、99.5%、99.3%和99.2%.检测限分别为1、1、0.6和1ng. 相似文献
3.
建立骨健灵膏含量测定方法.采用气相色谱法,PEG-20M气相色谱柱,柱温为140℃,氢火焰离子化检测器(FID),载气为N2,流速为50ml·min-1,进样口温度为190℃,樟脑在0.228~9.120μg范围内线性关系良好(r=1.0000),平均回收率为98.63%,RSD为1.48%(n=5).本法简便、准确、快速;适用于樟脑药材及其制剂的质量控制. 相似文献
4.
目的观察抑酸药(法莫替丁、鼠李铋镁)对马来酸多潘立酮(健胃药)在健康人体药代动力学的影响。方法10名健康受试者未服和服用抑酸药后,单剂量口服马来酸多潘立酮10mg,用LC/MS/MS测定血药浓度,用Win-NonLin5.0软件计算药代动力学参数,并用Spss12.0软件比较主要药代动力学参数。结果未服和服用抑酸药后,单剂量口服马来酸多潘立酮,其药代动力学参数如下:tmax分别为(0.85±0.24)、(2.20±1.78)h,Cmax分别为(9.68±5.37)、(7.18±4.12)μg.L-1,AUC0~tn分别为(38.18±19.76)、(49.96±10.35)μg.h.L-1。显示服用抑酸药后,马来酸多潘立酮的tmax延长,有显著性差异(P=0.04);AUC0-tn增加,峰浓度降低,但无显著性差异(分别为P=0.1、0.06)。结论在健康人体内,法莫替丁、鼠李铋镁不影响马来酸多潘立酮的吸收程度;但使其吸收速度减慢。 相似文献
5.
Patricia B. Roth Michael J. Twiner Zhihong Wang Marie-Yasmine Bottein Dechraoui Gregory J. Doucette 《Toxicon》2007,50(8):1175-1191
Flavobacteriaceae (strain S03) and Cytophaga sp. (strain 41-DBG2) are algicidal bacteria active against the brevetoxin (PbTx)-producing, red tide dinoflagellate, Karenia brevis. Little is known about the fate of PbTx associated with K. brevis cells following attack by such bacteria. The fate and distribution of PbTx in K. brevis cultures exposed to these algicidal strains were thus examined by receptor binding assay and liquid chromatography/mass spectrometry (LC/MS) in three size fractions (>5, 0.22–5, <0.22 μm) over a 2-week time course. In control cultures, brevetoxin concentrations in the >5 μm particulate size fraction correlated with changes in cell density, whereas significant increases in dissolved (i.e., <0.22 μm) toxin were observed in the later stages of culture growth. Exposure of K. brevis to either of the two algicidal bacteria tested caused cell lysis, coinciding with a rapid decline in the >5 μm PbTX size fraction and a simultaneous release of dissolved toxin into the growth medium. Upon cell lysis, dissolved brevetoxin accounted for ca. 60% of total toxin and consisted of 51–82% open A-ring derivatives. Open A-ring PbTx-2 and PbTx-3 derivatives bound with lower affinity (approximately 22- and 57-fold, respectively) to voltage-gated sodium channels and were considerably less cytotoxic (86- and 142-fold, respectively) to N2A cells than their individual parent toxins (i.e., PbTx-2 and PbTx-3). These novel findings of changes in PbTx size-fractioned distribution and overall reduction in K. brevis toxicity following attack by algicidal bacteria improve our understanding of potential trophic transfer routes and the fate of PbTx during red tide events. Moreover, this information will be important to consider when evaluating the potential role of algicidal bacteria in harmful algal bloom (HAB) management strategies involving control of bloom populations. 相似文献
6.
目的测定栀子提取物中大孔吸附树脂残留的苯是否符合限量要求.方法使用气相色谱仪,采用DB-624毛细管色谱柱,以氮气为载气,FID检测器,测定苯.结果栀子提取物中未检出苯,检出限为0.06mg·L-1.结论该方法简便、准确、重复性好,可用于栀子提取物的质量控制. 相似文献
7.
目的:建立高效液相色谱-质谱/质谱联用法(HPLC-MS/MS)测定血浆中牡荆素的方法,并用于大鼠药动学研究。方法:采用Capcell Pak C18柱(50 mm×2.0 mm,I.D.,5μm),柱温25℃,流动相为甲醇∶水(95∶5,0.1%甲酸),流速为0.2 mL/min。用负离子电喷雾电离源,多反应方式检测,选择监测的离子反应为m/z 431~311(牡荆素)和m/z 269~225(大黄素,内标)。结果:牡荆素在0.5~2 000 ng/mL线性关系良好,相关系数为0.9960,最低定量限为0.5 ng/mL。加样回收率76.1%~89.0%,日内日间精密度RSD均小于11%。结论:该方法分析速度快、操作简单、灵敏度高,可用于大鼠血浆中牡荆素的浓度测定及药动学研究。 相似文献
8.
目的建立痛可舒酊中冰片的含量测定方法。方法气相色谱法。PEG-20M为固定相,涂布浓度为10%,柱长3.2m,检测器为FID,载气为氮气,色谱柱温:150℃。结果在2.50~20.0mg/ml的范围内线性关系良好,平均回收率为99.06%,RSD为2.70%。结论该法简便高效,结果准确可靠,可用于痛可舒酊的质量控制。 相似文献
9.
Riccardo Manca Micaela Mitolo Maria Rosaria Stabile Francesca Bevilacqua Basil Sharrack 《Postgraduate medicine》2013,125(7):523-532
Objectives: Many people affected by multiple sclerosis (MS) experience cognitive impairment, especially decreases in information processing speed (PS). Neural disconnection is thought to represent the neural marker of this symptom, although the role played by alterations of specific functional brain networks still remains unclear. The aim is to investigate and compare patterns of association between PS-demanding cognitive performance and functional connectivity across two MS phenotypes.Methods: Forty patients with relapsing-remitting MS (RRMS) and 25 with secondary progressive MS (SPMS) had neuropsychological and MRI assessments. Multiple regression models were used to investigate the relationship between performance on tests of visuomotor and verbal PS, and on the verbal fluency tests, and functional connectivity of four cognitive networks, i.e. left and right frontoparietal, salience and default-mode, and two control networks, i.e. visual and sensorimotor.Results: Patients with SPMS were older and had longer disease history than patients with RRMS and presented with worse overall clinical conditions: higher disease severity, total lesion volume, and cognitive impairment rates. However, in both patient samples, cognitive performance across tests was negatively correlated with functional connectivity of the salience and default-mode networks, and positively with connectivity of the left frontoparietal network. Only the visuomotor PS scores of the RRMS group were also associated with connectivity of the sensorimotor network.Conclusions: PS-demanding cognitive performance in patients with MS appears mainly associated with strength of functional connectivity of frontal networks involved in the evaluation and manipulation of information, as well as the default mode network. These results are in line with the hypothesis that multiple neural networks are needed to support normal cognitive performance across MS phenotypes. However, different PS measures showed partially different patterns of association with functional connectivity. Therefore, further investigations are needed to clarify the contribution of inter-network communication to specific cognitive deficits due to MS. 相似文献
10.
《Clinical toxicology (Philadelphia, Pa.)》2013,51(5):446-447
AbstractBackground. Diphenidine (1-(1,2-diphenylethyl)piperidine) and its 2-methoxylated derivative methoxphenidine (MXP, 2-MeO-diphenidine) are substances with dissociative effects that were recently introduced for “recreational” purpose through the online-based sale of new psychoactive substances (NPS). A number of analytically confirmed non-fatal intoxications associated with diphenidine or MXP have occurred in Sweden and were included in the STRIDA project. Study design. Observational case series of consecutive patients with admitted or suspected intake of NPS and requiring intensive treatment in an emergency room and hospitalization in Sweden. Patients and methods. Blood and urine samples were collected from intoxicated patients presenting at emergency departments all over the country. NPS analysis was performed by multi-component liquid chromatography–mass spectrometry methods. Data on clinical features were collected during telephone consultations with the Poisons Information Centre and retrieved from medical records. Information was also obtained from online drug discussion forums. Case series. Over a 12-month period from January to December 2014, 750 cases of suspected NPS intoxication originating from emergency departments were enrolled in the STRIDA project of which 14 (1.9%) tested positive for diphenidine and 3 (0.4%) tested positive for MXP. Co-exposure to several other NPS (e.g., 5-/6-(2-aminopropyl)benzofuran, 2-4-bromomethcathinone, butylone, 3,4-dichloromethylphenidate, 5-methoxy-N-isopropyltryptamine, methiopropamine, and α-pyrrolidinopentiothiophenone), also including other dissociative substances (3-/4-methoxyphencyclidine), and classical drugs of abuse (e.g., cannabis and ethanol) was documented in 87% of these cases. The 17 patients were aged 20–48 (median: 32) years, and 13 (76%) were men. They commonly presented with hypertension (76%), tachycardia (47%), anxiety (65%), and altered mental status (65%) including confusion, disorientation, dissociation, and/or hallucinations. Eight patients (47%) displayed severe intoxication (Poisoning Severity Score 3). The diphenidine- or MXP-positive patients required hospitalization for 1–3 (median: 2) days. In addition to standard supportive therapy, half of the cases were treated with benzodiazepines and/or propofol. Conclusion. The adverse effects noted in analytically confirmed cases of NPS intoxication involving diphenidine or MXP were similar to those reported for other dissociative substances such as ketamine and methoxetamine. However, the high proportion of polysubstance use might have played a role in the intoxication and clinical features in some cases. 相似文献