A modality-specific somatosensory evoked potential test protocol for clinical evaluation: A feasibility study

ObjectiveWe aimed to establish an objective neurophysiological test protocol that can be used to assess the somatosensory nervous system.MethodsIn order to assess most fiber subtypes of the somatosensory nervous system, repetitive stimuli of seven different modalities (touch, vibration, pinprick, cold, contact heat, laser, and warmth) were synchronized with the electroencephalogram (EEG) and applied on the cheek and dorsum of the hand and dorsum of the foot in 21 healthy subjects and three polyneuropathy (PNP) patients. Latencies and amplitudes of the modalities were assessed and compared. Patients received quantitative sensory testing (QST) as reference.ResultsWe found reproducible evoked potentials recordings for touch, vibration, pinprick, contact-heat, and laser stimuli. The recording of warm-evoked potentials was challenging in young healthy subjects and not applicable in patients. Latencies were shortest within Aβ-fiber-mediated signals and longest within C-fibers. The test protocol detected function loss within the Aβ-fiber and Aδ-fiber-range in PNP patients. This function loss corresponded with QST findings.ConclusionIn this pilot study, we developed a neurophysiological test protocol that can specifically assess most of the somatosensory modalities. Despite technical challenges, initial patient data appear promising regarding a possible future clinical application.SignificanceEstablished and custom-made stimulators were combined to assess different fiber subtypes of the somatosensory nervous system using modality-specific evoked potentials.     

Effect of short-term administration of lead to pregnant rats.

Lead was administred to adult female rats in drinking water (0;0.1:1 and 10 ppm) for 3 weeks before mating, during pregnancy and during 3 weeks after delivery. On day 21 after delivery the mothers and their newborns were sacrified and various parameters of blood -- lead concentration on (Pb-B), hematocrit (Htc), hemoglobin (Hb), free erythrocyte porphyrins (FEP), delta0aminolevulinate dehydratase (ALAD) -- and tissue -- ALAD, free tissue porphyrins (FTP), lead concentration (Pb-T) -- were determined. In mothers a significant increase in Pb-B and Pb concentration in kidney was found in the 10 ppm group, but this increase in lead concentration was not associated with any statistically significant modification of the biochemical parameters. In newborns, lead concentration in blood and in kidney was also significantly increased in the 10 ppm group and this lead exposure was associated with a decrease of the ALAD activity in blood and an increase of FTP in kidney. On the basis of the biochemical parameters investigated one can therefore conclude that the developing organism is more susceptible to the biological action of lead than the organism of adult animals and that the "no-effect" level of lead administered during pregnancy and in the neonatal period is around 1 ppm.     

PKCδ在游离脂肪酸诱导内皮细胞凋亡过程中的作用研究

目的：探讨蛋白激酶 Cδ（PKCδ）在游离脂肪酸（FFAs）诱导内皮细胞凋亡过程中的作用。方法培养人脐静脉内皮细胞,分别给予不同浓度的 FFAs 刺激,转染 PKCδsiRNA 以抑制 PKCδ的表达。使用比色法检测细胞的增殖情况,采用定量流式细胞术测定细胞凋亡情况,免疫印迹法检测 PKCδ蛋白及磷酸化蛋白的表达水平。结果在人脐静脉内皮细胞内 FFAs 可产生多种效应,包括浓度依赖性的抑制细胞增殖、诱导细胞凋亡、增加 PKCδ的表达和磷酸化等。抑制 PKCδmRNA 的表达可导致 FFAs 诱导细胞凋亡减少。结论PKCδ可能介导内皮细胞中 FFAs 诱导的细胞凋亡。     

Safety,Pharmacokinetics, and Pharmacodynamics of ME-401, an Oral,Potent, and Selective Inhibitor of Phosphatidylinositol 3-Kinase P110δ, Following Single Ascending Dose Administration to Healthy Volunteers

Purpose

ME-401 is a novel selective inhibitor of phosphatidylinositol 3 kinase p110δ, an enzyme often found overexpressed and overactive in B-cell malignancies. The current study was performed to assess the safety, tolerability, pharmacokinetics, and pharmacodynamics of single ascending oral doses of ME-401 in healthy volunteers.

PPARβ/δ在兔动脉粥样硬化模型中的表达及作用

目的 研究过氧化物酶体增殖物激活受体（Peroxisome Proliferators-activated Receptor,PPAR）-β/δ在兔动脉粥样硬化模型中的表达水平和作用方式。方法 35只雄性新西兰大白兔分为对照组（5只）、高脂组（15只）和球囊损伤组（15只）,后两组进一步分为6周、8周、10周组,每组5只。实时定量PCR（Real-time Quantitative PCR）用来检测PPARβ/δm RNA的水平,免疫组织化学法（Immunohistochemistry,IHC）和蛋白质印迹法（Western Blotting,WB）检测PPARβ/δ蛋白的表达,酶联免疫吸附试验（Enzyme-linked Immunosorbent Assay,ELISA）测定兔血清中炎症因子肿瘤坏死因子（tumor necrosis factor,TNF）-α,白介素（interleukin,IL）-6,IL-8和IL-10的水平。结果 高脂组和球囊损伤组的PPARβ/δ蛋白质和m RNA水平与对照组相比显著增加（P〈0.01）。此外,高脂组PPARβ/δ蛋白质水平在6-10周增加显著（P〈0.01）,PPARβ/δm RNA在8-10周组之间有显著性差异,6-8周组之间也有明显差异（P〈0.05）。PPARβ/δ蛋白质和m RNA水平在球囊损伤组各亚组之间差异显著（P〈0.01）,而且,球囊损伤组PPARβ/δ的表达水平比同一时间点的高脂组明显增加（P〈0.01）。高脂组和球囊损伤组,血清TNF-α、IL-6、IL-8和IL-10的水平与对照组相比明显上升。结论 PPARβ/δ可能参与动脉粥样硬化的进程并发挥重要作用。     

3H] pregabalin binding is increased in ipsilateral dorsal horn following chronic constriction injury

Pregabalin, a 3-substituted analogue of gamma-amino butyric acid has recently been approved for treatment of neuropathic pain. We have investigated the anatomical binding profile of [(3)H] pregabalin following chronic constriction injury (CCI) and compared this with alpha 2 delta 1 subunit expression using in situ hybridisation. We report here that the intensity and distribution pattern of [(3)H] pregabalin binding is altered in the ipsilateral dorsal horn following CCI and this is associated with a corresponding increase in alpha 2 delta 1 mRNA in the ipsilateral dorsal root ganglion (DRG). It is likely that increased DRG mRNA production leads to increased alpha 2 delta 1 protein production and subsequent transport by primary afferents to the dorsal horn. The increased expression of calcium channel subunits and protein in central terminals is interesting, given that abnormal activity within sensory nerves is likely to significantly contribute to the symptomatology of neuropathic pain. The upregulation of pregabalin binding sites in sensory nerve terminals may occur as part of the response to nerve damage in neuropathic pain patients, and therefore, preferential actions of pregabalin at these sites may contribute to its mechanism of action in man.     

The possible mechanisms of protocatechuic acid-induced central analgesia

It is aimed to investigate the central antinociceptive effect of protocatechuic acid and the involvement of stimulation of opioidergic, serotonin 5-HT_2A/2C, α2-adrenergic and muscarinic receptors in protocatechuic acid-induced central analgesia in mice. Time-dependent antinociceptive effects of protocatechuic acid at the oral doses of 75, 150 and 300?mg/kg were tested in hot-plate (integrated supraspinal response) and tail-immersion (spinal reflex) tests in mice. To investigate the mechanisms of action; the mice administered 300?mg/kg protocatechuic acid (p.o.) were pre-treated with non-specific opioid antagonist naloxone (5?mg/kg, i.p.), serotonin 5-HT_2A/2C receptor antagonist ketanserin (1?mg/kg, i.p.), α2-adrenoceptor antagonist yohimbine (1?mg/kg, i.p.) and non-specific muscarinic antagonist atropine (5?mg/kg, i.p.), respectively. The antinociceptive effect of protocatechuic acid was observed at the doses of 75, 150 and 300?mg/kg in tail-immersion test, at the doses of 150 and 300?mg/kg in hot-plate test at different time interval. The enhancement in the latency of protocatechuic acid-induced response to thermal stimuli was antagonized by yohimbine, naloxone and atropine in tail-immersion test, while it was antagonized only by yohimbine and naloxone pretreatments in hot-plate test. These results indicated that protocatechuic acid has the central antinociceptive action that is probably organized by spinal mediated cholinergic and opiodiergic, also spinal and supraspinal mediated noradrenergic modulation. However, further studies are required to understand how protocatechuic acid organizes the interactions of these modulatory systems. As a whole, these findings reinforce that protocatechuic acid is a potential agent that might be used for pain relief. Additionally, the clarification of the effect and mechanisms of action of protocatechuic acid will contribute to new therapeutic approaches and provide guidance for new drug development studies.     

抑制剂Rottlerin对巨噬细胞在结核分枝杆菌刺激下NO和TNF分泌的影响

目的 研究蛋白激酶C-δ在巨噬细胞识别结核分枝杆菌后产生免疫应答过程中的作用,探讨固有免疫抗结核的分子机制。方法 用蛋白酶抑制剂预处理体外培养的小鼠巨噬细胞,通过Western Blot分析相关蛋白的表达及磷酸化水平,利用Griess法和ELISA方法检测巨噬细胞在结核分枝杆菌索状因子合成类似物TDB的刺激下释放一氧化氮（NO）和分泌肿瘤坏死因子（TNF）的水平。结果 Syk抑制剂Piceatannol能抑制TDB诱导的PKC-δ磷酸化;经过蛋白激酶C-δ抑制剂Rottlerin的处理,巨噬细胞受TDB诱导释放的NO浓度由对照组的30μM降至5μM,分泌的TNF浓度为对照组的10%。结论 蛋白激酶C-δ抑制剂Rottlerin抑制TDB诱导的巨噬细胞释放NO和分泌TNF,提示PKC-δ在抗结核固有免疫中发挥重要的作用。