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61.
《Acta orthopaedica》2013,84(4):388-390
Fourteen patients with severe, chronic sciatica operated on repeatedly but without lasting success were treated by two intrathecal injections of methyl prednisolone (40 mg and 80 mg) at an interval of a few days. Significant improvement was obtained with regard to pain in many cases, but as there was no control series it is difficult to assess the results. 相似文献
62.
Ze-Jun Wang Boris Tabakoff Simon R Levinson Thomas Heinbockel 《Acta pharmacologica Sinica》2015,36(7):791-799
Aim:
Methyl eugenol is a major active component extracted from the Chinese herb Asari Radix et Rhizoma, which has been used to treat toothache and other pain. Previous in vivo studies have shown that methyl eugenol has anesthetic and antinociceptive effects. The aim of this study was to determine the possible mechanism underlying its effect on nervous system disorders.Methods:
The direct interaction of methyl eugenol with Na+ channels was explored and characterized using electrophysiological recordings from Nav1.7-transfected CHO cells.Results:
In whole-cell patch clamp mode, methyl eugenol tonically inhibited peripheral nerve Nav1.7 currents in a concentration- and voltage-dependent manner, with an IC50 of 295 μmol/L at a −100 mV holding potential. Functionally, methyl eugenol preferentially bound to Nav1.7 channels in the inactivated and/or open state, with weaker binding to channels in the resting state. Thus, in the presence of methyl eugenol, Nav1.7 channels exhibited reduced availability for activation in a steady-state inactivation protocol, strong use-dependent inhibition, enhanced binding kinetics, and slow recovery from inactivation compared to untreated channels. An estimation of the affinity of methyl eugenol for the resting and inactivated states of the channel also demonstrated that methyl eugenol preferentially binds to inactivated channels, with a 6.4 times greater affinity compared to channels in the resting state. The failure of inactivated channels to completely recover to control levels at higher concentrations of methyl eugenol implies that the drug may drive more drug-bound, fast-inactivated channels into drug-bound, slow-inactivated channels.Conclusion:
Methyl eugenol is a potential candidate as an effective local anesthetic and analgesic. The antinociceptive and anesthetic effects of methyl eugenol result from the inhibitory action of methyl eugenol on peripheral Na+ channels. 相似文献63.
Glutamate (Glu) N-methyl-D-aspartate (NMDA) receptor is present in the lungs, and NMDA receptor antagonist MK-801 attenuates oxidant lung injury. We hypothesized that Glu excitotoxicity may participate in the pathogenesis of hyperoxia-induced lung injury. To determine possible pulmonary protective effects, we administered 0.05 ml/kg MK-801 or saline intraperitoneally daily to neonatal rats exposed to more than 95% oxygen in air. After 7 days, MK-801 decreased the hyperoxia-associated elevation of wet-to-dry lung weight, total leukocyte and neutrophil counts, total protein and lactate dehydroase in BAL fluid, total myeloperoxidase activity, and lung pathological injury. MK-801 inhibited hyperoxia-associated increments in reactive oxygen species production and NF-kappaB production. Hence, NMDA receptor antagonist MK-801 ameliorates hyperoxia-induced lung injury in neonatal rats, and is associated with decreased reactive oxygen species and NF-kappaB. We conclude that Glu may play an important role in hyperoxia-induced lung injury by activation of NMDA receptor. 相似文献
64.
Christiane Bergamasco RD Lilian Mika Horie RD Raquel Susana Torrinhas BD Dan L. Waitzberg MD PhD 《JPEN. Journal of parenteral and enteral nutrition》2015,39(8):941-947
Background: The daily consumption of dietary fiber is frequently below suggested recommendations. Using a double‐blind, controlled, randomized study, we assessed the efficiency and tolerance of a fiber‐enriched orange juice to supplement fiber intake in women. Materials and Methods: After 1 week of noninterventional observation, 192 healthy adult women ingested 400 mL of orange juice for 21 days, which either was not (placebo group) or was enriched with fiber (fiber group). Orange juice ingestion was registered daily and controlled for each week during the study period. Macronutrient, fiber, and energy intake were determined using a 3‐day food record, validated food chemical composition databases, and the “Pro Diet” software. Gastrointestinal symptoms were self‐evaluated daily by scoring 4 grades of symptom intensity and using a visual analog scale to grade pain severity. Results: No changes were observed for macronutrient and energy ingestion. For the placebo group (n = 97), the total fiber intake record was under the daily recommended value. In contrast, the fiber group (n = 95) displayed higher comparative values of total and soluble fiber consumption (P ≤ .001), achieving the daily recommended values of fiber intake. Both groups reported an increased frequency of slight bloating and rumbles over time (P ≤ .05). The fiber group also experienced a higher frequency of slight flatulence over time (P = .002). Conclusion: Consumption of fiber‐enriched orange juice was efficient to achieve the daily fiber intake recommendation for women, was not accompanied by intense adverse events, and may represent a suitable method to supplement fiber intake in woman. 相似文献
65.
Oxytocin in the regulation of social behaviours in medial amygdala‐lesioned mice via the inhibition of the extracellular signal‐regulated kinase signalling pathway 下载免费PDF全文
Yu Wang Shanshan Zhao Zhe Wu Yu Feng Chuansheng Zhao Chaodong Zhang 《Clinical and experimental pharmacology & physiology》2015,42(5):465-474
The neuropeptide oxytocin (OXT) has been implicated in the pathophysiology of behavioural deficits among patients with autism spectrum disorder (ASD). However, the molecular mechanisms underlying its role in ASD remain unclear. In the present study, a murine model with ASD‐like phenotypes was induced by intra‐medial amygdala injection of N‐methyl‐d ‐aspartate, and it was used to investigate the role of OXT in behaviour regulation. Behavioural tests were performed to verify the ASD‐like phenotypes of N‐methyl‐d ‐aspartate‐treated mice, and the results showed that mice with bilateral medial amygdala lesions presented significant behavioural deficits, including impaired learning and memory and increased anxiety and depression. We also observed a notably decreased level of OXT in both the plasma and the hypothalamus of medial amygdala‐lesioned mice, and the extracellular signal‐regulated kinase (ERK) was activated. Further studies demonstrated that the administration of OXT alleviated ASD‐like symptoms and significantly inhibited phosphorylation of ERK; the inhibitory effect was similar to that of U0126, an ERK signalling inhibitor. In addition, OXT administration modulated the expression of downstream proteins of the ERK signalling pathway, such as cyclic adenosine monophosphate response element binding and c‐fos. Taken together, our data indicate that OXT plays an important role in ameliorating behavioural deficits in an ASD‐like mouse model, which was mediated by inhibiting the ERK signalling pathway and its downstream proteins. 相似文献
66.
F. H. BOSCH J. M. WERRE B. ROERDINKHOLDER-STOELWINDER T. H. HULS S. G. L. VD. VEGT F. L. A. WILLEKENS M. BINS M. R. HALIE 《International journal of laboratory hematology》1993,15(4):265-274
Summary A recently described separation technique consisting of a combination of counterflow centrifugation and subsequent density (Percoll) scparation was tested for its ability to enrich red cell populations with young cells in comparison to either separation technique alone. The relative age of every fraction was determined by HbAlc measurements, resulting in the lowest HbAlc for the combination method. Conventional reticulocyte counting and floweytometric counting with thiazole orange indicated that in the youngest fractions the combination method showed the highest reticulocyte counts. There was a good correlation between manual and flowcytometric counting results. Radio-iron studies showed a two-fold enrichment with young cells in the fraction with the lowest HbAIc acquired by the combination technique in comparison to the other two methods. Cytometric measurements showed that the fractions with the lowest HbAlc were the ones with the highest MCV and MCH and the lowest MCHC. Besides loss of their RNA-material, young cells already seem to loose water and haemoglobin like older cells, resulting in a decrease of MCV and MCH and in increase in MCHC. It is concluded that combining counterflow centrifugation with subsequent density fractionation results in superior enrichment with young cells in comparison to the results of each method alone. 相似文献
67.
Christopher C. Waller Sumudu A. Weththasinghe Lauren McClure Adam T. Cawley Craig Suann Emily Suann Emma Sutherland Elliot Cooper Alison Heather Malcolm D. McLeod 《Drug testing and analysis》2020,12(6):752-762
Hemapolin (2α,3α‐epithio‐17α‐methyl‐5α‐androstan‐17β‐ol) is a designer steroid that is an ingredient in several “dietary” and “nutritional” supplements available online. As an unusual chemical modification to the steroid A‐ring could allow this compound to pass through antidoping screens undetected, the metabolism of hemapolin was investigated by an in vivo equine drug administration study coupled with GC‐MS analysis. Following administration of synthetically prepared hemapolin to a thoroughbred horse, madol (17α‐methyl‐5α‐androst‐2‐en‐17β‐ol), reduced and dihydroxylated madol (17α‐methyl‐5α‐androstane‐2β,3α,17β‐triol), and the isomeric enone metabolites 17β‐hydroxy‐17α‐methyl‐5α‐androst‐3‐en‐2‐one and 17β‐hydroxy‐17α‐methyl‐5α‐androst‐2‐en‐4‐one, were detected and confirmed in equine urine extracts by comparison with a library of synthetically derived reference materials. A number of additional madol derivatives derived from hydroxylation, dihydroxylation, and trihydroxylation were also detected but not fully identified by this approach. A yeast cell‐based androgen receptor bioassay of available reference materials showed that hemapolin and many of the metabolites identified by this study were potent activators of the equine androgen receptor. This study reveals the metabolites resulting from the equine administration of the androgen hemapolin that can be incorporated into routine GC‐MS antidoping screening and confirmation protocols to detect the illicit use of this agent in equine sports. 相似文献
68.
目的 获得远志Polygala tenuifolia响应茉莉酸甲酯(methyl jasmonate,MeJA)处理的转录组学信息,挖掘远志三萜类化合物骨架生物合成的关键酶基因。方法 以生长30 d的远志组培苗为材料,分别用无菌水(CK)、50 μmol/L MeJA、100 μmol/L MeJA处理24 h,采用Illunima HiseqTM 2000 150PE进行转录组测序,使用Trinity软件完成Unigene的de novo拼接,基于BLAST实现Unigene的分类、功能注释、代谢通路分析、蛋白功能注释、差异基因分析和筛选等。结果 最终获得52.19 Gb数据,通过de novo拼接注释得到Unigene 54 426条,平均长度为1 604 bp,注释成功率100%。通过对MeJA处理前后基因进行差异分析,共筛选出差异基因3 390个,其中有1 287个上调,2 103个下调,且以100 μmol/L MeJA处理的差异基因总数及上调数最高。KEGG富集分析表明,差异基因主要富集于苯丙烷类生物合成、半胱氨酸与蛋氨酸代谢、淀粉蔗糖代谢、光合生物的固碳作用、萜类骨架生物合成等KEGG通路中。找到与远志三萜类骨架生物合成相关的基因59条,其中AACT、HMGS、HMGR、MK、PMK、MPD、DXS、IDI、FPPS、SQS、SE和β-AS受MeJA诱导后表达量上调。结论 对MeJA处理后的远志幼苗转录组进行分析,获得远志三萜类骨架生物合成相关的候选基因,MeJA可以诱导其三萜类骨架合成相关基因的表达,为远志的分子生物学研究提供了丰富的数据资源,也为后期开展远志三萜皂苷类化合物次生代谢途径解析奠定了基础。 相似文献
69.
Murat Uygun Begüm Akduman Bülent Ergönül Sinan Akgöl Adil Denizli 《Journal of biomaterials science. Polymer edition》2013,24(16):1112-1125
Poly(methyl methacrylate-glycidyl methacrylate) [Poly(MMA-GMA)] cryogels were synthesized using monomers of methylmethacrylic acid and epoxy group bearing GMA via radical cryopolymerization technique. Synthesized cryogels were used for the immobilization of amyloglucosidase to the cryogel surface using epoxy chemistry. Characterizations of the free and immobilized amyloglucosidase were carried out by comparing the optimum and kinetic parameters of enzymes. For this, pH and temperature profiles of free and immobilized preparation were studied and, it was found that, optimum pH of enzyme was not change upon immobilization (pH 5.0), while optimum temperature of the enzyme shifted 10 °C to warmer region after immobilization (optimum temperatures for free and immobilized enzyme were 55 and 65 °C, respectively). Kinetic parameters of free and immobilized enzyme were also investigated and Km values of free and immobilized amyloglucosidase were found to be 2.743 and 0.865 mg/mL, respectively. Vmax of immobilized amyloglucosidase was found to be (0.496 µmol/min) about four times less than that of free enzyme (2.020 µmol/min). Storage and operational stabilities of immobilized amyloglucosidase were also studied and it was showed that immobilized preparation had much more stability than free preparation. In the present work, amyloglucosidase immobilized poly(MMA-GMA) cryogels were used for continuous glucose syrup production from starch for the first time. Efficiency of immobilized enzyme was investigated and released amount of glucose was found to be 2.54 mg/mL at the end of the 5 min of hydrolysis. The results indicate that the epoxy functionalized cryogels offer a good alternative for amyloglucosidase immobilization applications with increased operational and thermal stability, and reusability. Also, these cryogels can be used for immobilization of other industrially valuable enzymes beyond amyloglucosidase. 相似文献
70.
Lucas D. Sanches Sergio A. A. Santos Jaqueline R. Carvalho Gabriela D. M. Jeronimo Wagner J. Favaro Maria D. G. Reis Sérgio L. Felisbino Luis A. Justulin Jr 《International journal of experimental pathology》2013,94(6):362-372
Despite recent advances in understanding the biological basis of prostate cancer (PCa), the management of this disease remains a challenge. Chemoprotective agents have been used to protect against or eradicate prostate malignancies. Here, we investigated the protective effect of γ‐tocopherol on N‐methyl‐N‐nitrosourea (MNU)‐induced epithelial dysplasia in the rat ventral prostate (VP). Thirty‐two male Wistar rats were divided into four groups (n = 8): control (CT): healthy control animals fed a standard diet; control+γ‐tocopherol (CT+γT): healthy control animals without intervention fed a γ‐tocopherol‐enriched diet (20 mg/kg); N‐methyl‐N‐nitrosourea (MNU): rats that received a single dose of MNU (30 mg/kg) plus testosterone propionate (100 mg/kg) and were fed a standard diet; and MNU+γ‐tocopherol (MNU+γT): rats that received the same treatment of MNU plus testosterone and were fed with a γ‐tocopherol‐enriched diet (20 mg/kg). After 4 months, the VPs were excised to evaluate morphology, cell proliferation and apoptosis, as well as cyclooxygenase‐2 (Cox‐2), glutathione‐S‐transferase‐pi (GST‐pi) and androgen receptor (AR) protein expression, and matrix metalloproteinase‐9 (MMP‐9) activity. An increase in the incidence of epithelial dysplasias, such as stratified epithelial hyperplasia and squamous metaplasia, in the MNU group was accompanied by augmented cell proliferation, GST‐pi and Cox‐2 immunoexpression and pro‐MMP‐9 activity. Stromal thickening and inflammatory foci were also observed. The administration of a γ‐tocopherol‐enriched diet significantly attenuated the adverse effects of MNU in the VP. The incidence of epithelial dysplasia decreased, along with the cell proliferation index, GST‐pi and Cox‐2 immunoexpression. The gelatinolytic activity of pro‐MMP‐9 returned to the levels observed for the CT group. These results suggest that γ‐tocopherol acts as a protective agent against MNU‐induced prostatic disorders in the rat ventral prostate. 相似文献