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1.
The mechanism by which 2(3H)-benzothiazolone, 4-hydroxy-7-[2-[[2-[[3-(2-phenylethoxy)propyl]-sulphonyl]ethyl]amino]ethyl]-monohydrochloride (AR-C68397AA; viozan), a dual dopamine D2/beta2-adrenoceptor agonist which has shown promise in the treatment of chronic obstructive pulmonary disease (COPD), inhibits the extravasation of plasma protein induced by capsaicin in the tracheas of Brown Norway rats has been re-evaluated. Viozan (10-30 microg/kg given intratracheally; i.t.) inhibited dose-dependently the extravasation of plasma protein tagged with Evans Blue into rat trachea induced by capsaicin (10 microg/kg i.t.). Similar effects were seen with the selective beta2-adrenoceptor agonist, salbutamol (3-10 microg/kg i.t.), but the selective dopamine D2 receptor agonist, quinagolide (10-30 microg/kg i.t.), was inactive. The effects of viozan and salbutamol were abolished by propranolol (3 mg/kg) given intraperitoneally (i.p.) but unaffected by sulpiride (3 mg/kg i.p.). Thus, in c,ontrast to claims in the literature, a functional response to dopamine D2 receptor activation in a preclinical model of oedema arising from sensory nerve fibre activation in the rat lung could not be demonstrated. Moreover, no qualitative difference could be demonstrated between the response to a dual D2/beta2-adrenoceptor agonist and a selective beta2-adrenoceptor agonist. The observations call into question whether a dual D2/beta2-adrenoceptor agonist such as viozan would bring added benefit over established selective beta2-adrenoceptor agonists in the therapy  相似文献   

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3.
Nitrogen-containing bisphosphonates (NBPs), anti-bone-resorptive drugs, exhibit inflammatory side effects (fever, jaw osteomyelitis or osteonecrosis, etc.). We previously reported that in mice: (i) a single intraperitoneal injection of alendronate (an NBP, 40 μmol/kg or less) induces various inflammatory reactions, (ii) these effects, which are minimal in IL-1-deficient mice, can be prevented by co-administration of clodronate (a non-NBP, 40 μmol/kg or less), and (iii) alendronate increases IL-1β in tissues (liver, spleen, and lung), but strangely not in blood. Here, we found the following in mice. (a) The IL-1β in tissues is pro-IL-1β. (b) Unlike LPS, alendronate induces minimal activation of caspase-1 (pro-IL-1β-processing enzyme). (c) The tissue pro-IL-1β elevations are largely absent in macrophage-depleted mice. (d) In vitro, 100 μM alendronate directly stimulates RAW 264 cells (murine macrophage-like cells) to produce pro-IL-1β, and 1 μM clodronate inhibits this effect. These results suggest that in mice: (i) the major pro-IL-1β-producing cells in response to alendronate are macrophages, (ii) alendronate directly stimulates them to produce pro-IL-1β, but the release of mature IL-1β is below detectable levels due to insufficient activation of caspase-1, and (iii) clodronate inhibits the pro-IL-1β production by acting directly on macrophages, although the in vivo mechanism may differ from the in vitro one.  相似文献   

4.
Objective The aim of the study was to determine the changes in consumption of psychotropic drugs by children aged less than 18 years during the years 1995 to 2001 in the Netherlands.Methods The year prevalence of antipsychotics, benzodiazepines, antidepressants and psychostimulants for boys and girls under 18 years was determined using electronic pharmacy dispensing records obtained from the PHARMO database.Results The overall prevalence of psychotropic drugs increased from 11.1 per 1000 in 1995 to 22.9 per 1000 in 2001. This increase could almost completely be attributed to the increase in the use of psychostimulants, i.e. methylphenidate, which increased from 1.7 per 1000 children in 1995 to 10.0 per 1000 in 2001. For the other psychotropic drugs, no or only a small increase was seen. For both boys and girls, the use of psychostimulants was highest in the age group of 5–14 years.Conclusion During the years 1995–2001, the consumption of psychotropic drugs by children in the Netherlands has more than doubled. This increase could largely be attributed to an increased use of the psychostimulant methylphenidate by boys of the age 5–14 years.  相似文献   

5.
Suppression of oxygen toxicity by melatonin   总被引:6,自引:1,他引:5  
INTRODUCTIONOxygen(O2)istoxicbecauseofitshighelectron(e-)afinitywhichcausesittodegradeintoanumberofreactiveanddamaginginterme...  相似文献   

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Patterns of drug use among the elderly vary greatly depending on level of cognitive function, yet no systematic evaluation of drug use by type of dementia has been performed. We compared patterns of drug use among patients with Alzheimer's disease (AD) and vascular dementia (VaD) to examine their relation to cognitive impairment. We used a population-based data set with over 350,000 residents admitted between 1992 and 1995 to all Medicare-Medicaid-certified nursing homes in five states. After excluding patients with a history of mental disorders or retardation, we identified 23,073 patients age 65 years and over with a diagnosis of AD and 76,087 with VaD. We examined over 350 resident data items (demographic, diagnostic, clinical, treatment) collected with the federally mandated Minimum Data Set, drug data (brand name, dosage, route and frequency of administration for all drugs), and Medicare hospital claims. Cognitive status was measured with a 7-point cognitive performance scale. Estimates of drug use were adjusted for age, gender, race, and prevalence of respective disease. Patients with AD were younger and had more severe cognitive impairment than those with VaD. The latter had more comorbid clinical conditions (3.1 +/- 1.9 vs 2.3 +/- 1.7 for patients with AD) and received a greater number of total drugs (6.1 +/- 4.6 vs 5.3 +/- 4.3). Overall use of cardiovascular, anti-Parkinson, pulmonary, antineoplastic, and nutritional agents was less frequent among patients with AD than those with VaD. Results were consistent across different levels of cognitive impairment. Thus, patients with AD have fewer associated diseases and appear to be less intensively medically treated.  相似文献   

8.
Summary To investigate the effects of hydroxyl and methyl substitution of the alkyl bridge bond on the-adrenoceptor activity of arylalkylimidazole derivatives, the cardiovascular effects of the molecules were studied in anaesthetized and pithed rats. The compounds studied were 4(5)-substituted imidazole derivatives with a methano, ethano or etheno bridge between the imidazole and the 2-, 2,3- or 2,6-methyl substituted phenyl rings. The hypotensive and bradycardic activities of the molecules in the anaesthetized rat were always reduced by-hydroxylation and usually augmented by-methylation of the bridge between the imidazole and phenyl rings. Hydroxylation was associated with a consistent, marked decrease in vasopressor and sympatho-inhibitory activity in the cardiovascular system of the pithed rat, but a methyl moiety as a bulky substituent in the-position of the alkyl bridge did not decrease but even caused an increase in-adrenoceptor activity in this test system. The detrimental effect of-hydroxylation of the compounds at 1- and 2-adrenoceptors supports the notion that the interaction of the imidazoles at-adrenoceptor is different from that of the classical, noradrenaline-like phenethylamines. The results also suggest that the alkyl bridge between the phenyl and imidazole rings of the imidazoles may contribute directly to the binding process.  相似文献   

9.
Mitochondrial dynamics control mitochondrial morphology and function, and aberrations in these are associated with various neurodegenerative diseases including Alzheimer’s disease and Parkinson’s disease. To identify novel regulators of mitochondrial dynamics, we screened a phytochemical library and identified liquiritigenin as a potent inducer of mitochondrial fusion. Treatment with liquiritigenin induced an elongated mitochondrial morphology in SK-N-MC cells. In addition, liquiritigenin rescued mitochondrial fragmentation induced by knockout of mitochondrial fusion mediators such as Mfn1, Mfn2, and Opa1. Furthermore, we found that treatment with liquiritigenin notably inhibited mitochondrial fragmentation and cytotoxicity induced by Aβ in SK-N-MC cells.  相似文献   

10.

BACKGROUND AND PURPOSE

The opioid receptor family comprises four structurally homologous but functionally distinct sub-groups, the μ (MOP), δ (DOP), κ (KOP) and nociceptin (NOP) receptors. As most opioid agonists are selective but not specific, a broad spectrum of behaviours due to activation of different opioid receptors is expected. In this study, we examine whether other opioid receptor systems influenced KOP-mediated antinociception.

EXPERIMENTAL APPROACH

We used a tail withdrawal assay in C57Bl/6 mice to assay the antinociceptive effect of systemically administered opioid agonists with varying selectivity at KOP receptors. Pharmacological and genetic approaches were used to analyse the interactions of the other opioid receptors in modulating KOP-mediated antinociception.

KEY RESULTS

Etorphine, a potent agonist at all four opioid receptors, was not anti-nociceptive in MOP knockout (KO) mice, although etorphine is an efficacious KOP receptor agonist and specific KOP receptor agonists remain analgesic in MOP KO mice. As KOP receptor agonists are aversive, we considered KOP-mediated antinociception might be a form of stress-induced analgesia that is blocked by the anxiolytic effects of DOP receptor agonists. In support of this hypothesis, pretreatment with the DOP antagonist, naltrindole (10 mg·kg−1), unmasked etorphine (3 mg·kg−1) antinociception in MOP KO mice. Further, in wild-type mice, KOP-mediated antinociception by systemic U50,488H (10 mg·kg−1) was blocked by pretreatment with the DOP agonist SNC80 (5 mg·kg−1) and diazepam (1 mg·kg−1).

CONCLUSIONS AND IMPLICATIONS

Systemic DOP receptor agonists blocked systemic KOP antinociception, and these results identify DOP receptor agonists as potential agents for reversing stress-driven addictive and depressive behaviours mediated through KOP receptor activation.

LINKED ARTICLES

This article is part of a themed section on Opioids: New Pathways to Functional Selectivity. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2015.172.issue-2  相似文献   

11.
Guillain-Barré syndrome (GBS) is an autoimmune disease affecting the peripheral nerves, and is frequently associated with triggering events several weeks prior to the onset of symptoms. We report the case of a 68-year-old female who was diagnosed with GBS and subsequently developed myocarditis. She was treated with inotropic support and intravenous immunoglobulin (IVIG), and her condition improved. This presentation of GBS complicated by myocarditis is very rare. We examined the literature regarding this association.  相似文献   

12.
Ochratoxin (OTA) is one of the most abundant food contaminating mycotoxins and is commonly present in the food chain. Many of the effects associated with OTA, appear to be mediated through oxidative stress. Although the toxicity of OTA is fairly well characterized, antidotes for alleviating the toxicity are sparsely reported. Dietary antioxidants have gained much importance in the recent years for their antioxidative and therapeutic properties. In the present study the therapeutic strategy was directed towards use of quercetin, a dietary antioxidant to combat OTA-induced toxicity in Vero cell line. Our results demonstrate that quercetin pre-treatment suppressed OTA-induced cytotoxicity and oxidative stress. It modulated OTA-induced alteration on the antioxidant defence through activation of Nrf2 pathway. Morphological studies by scanning electron microscopy (SEM) and cell cycle analysis indicated that quercetin prevented OTA-induced apoptosis. It also inhibited the activation of caspase cascade that leads to DNA fragmentation. Quercetin also exhibited antigenotoxic potential by attenuating OTA-induced DNA damage and micronucleus (MN) formation. The results of the study demonstrate for the first time that quercetin pre-treatment prevents OTA-induced oxidative stress and apoptosis in Vero cell line.  相似文献   

13.
Hui Zhang  Meng Du  Yue Li  Yuhao Chen 《Drug delivery》2018,25(1):1740-1745
Gene therapy is a promising strategy for treatments of various diseases. Efficient and safe introduction of therapeutic genes into targeted cells is essential to realize functions of the genes. High-molecular-weight polyethylenimines (HMW PEIs) including 25?kDa branched PEI and 22?kDa linear PEI are widely used for in vitro gene transfection. However, high-gene transfection efficiency is usually accompanied with high cytotoxicity, which hampers their further clinical study. On the contrary, low-molecular-weight polyethylenimines (LMW PEIs) such as 1.8?kDa PEI and 800?Da PEI show good biocompatibility but their applications are limited by the poor DNA condensation capability. In this study, we find that 1.8?kDa PEI, but not 800?Da PEI combined with low-dose 25?kDa PEI could significantly promote gene transfection with low cytotoxicity. Plasmids encoding enhanced green fluorescence protein (EGFP) were delivered by the combined PEI and gene transfection efficiency was evaluated by microscopic observation and flow cytometry. Parameters including concentrations of 25?kDa PEI and 1.8?kDa PEI and preparation ways were further optimized. This study presents an efficient and safe combined PEI-based non-viral gene delivery strategy with potential for in vivo applications.  相似文献   

14.
Summary The release of acetylcholine evoked by field stimulation of the guinea-pig ileum (3 Hz) is increased by yohimbine and tolazoline but not affected by phentolamine. It is proposed that yohimbine and tolazoline by blocking -adrenoceptors of the cholinergic nerves abolish the inhibition caused by endogenous noradrenaline, and thus facilitate the output of acetylcholine.  相似文献   

15.

BACKGROUND AND PURPOSE

Microparticles (MPs), small membrane-bound particles originating from different cell types during activation or apoptosis, mediate intercellular communication, exert pro-coagulant activity and affect inflammation and other pathophysiological conditions. Monocyte-derived MPs have undergone little investigation and, to our knowledge, have never been evaluated for their possible autocrine effects. Therefore, we assessed the ability of monocyte-derived MPs to stimulate human monocytes and monocyte-derived macrophages (MDM).

EXPERIMENTAL APPROACH

MPs were generated from supernatants of human monocytes stimulated by the calcium ionophore A23187 (12 µM), and then characterized. Human monocytes and MDM of healthy donors were isolated by standard procedures. Cells were challenged by MPs or phorbol 12-myristate 13-acetate (PMA, used as standard stimulus), in the absence or presence of PPARγ agonists and antagonists. Superoxide anion production (measured spectrophotometrically), cytokine release (elisa), PPARγ protein expression (immunoblotting) and NF-κB activation (EMSA assay) were evaluated.

KEY RESULTS

Monocyte-derived MPs induced, in a concentration-dependent manner, oxygen radical production, cytokine release and NF-κB activation in human monocytes and macrophages, with lower effects than PMA. In both cell types, the PPARγ agonists rosiglitazone and 15-deoxy-Δ12,14-prostaglandin J2 (15d-PGJ2) inhibited MPs-induced stimulation and this inhibition was reversed by a PPARγ antagonist. In human monocyte/macrophages, MPs as well as rosiglitazone and 15d-PGJ2 induced PPARγ protein expression.

CONCLUSION AND IMPLICATIONS

In human monocyte/macrophages, monocyte-derived MPs exert an autocrine activation that was modulated by PPARγ ligands, inducing both pro-inflammatory (superoxide anion production, cytokine release and NF-κB activation) and anti-inflammatory (PPARγ expression) effects.  相似文献   

16.
Advanced therapy medicinal products (ATMPs) are the cutting edge of drug innovation. ATMPs have different challenges than other drug classes. To accommodate these challenges and facilitate science-driven development, flexibility in the requirements to demonstrate the safety and efficacy of this rapidly evolving drug class is necessary. To create flexibility, the European Union introduced the risk-based approach. This approach provides the possibility of omitting guideline-based studies based on risk analyses. To gain insight into the effect of the risk-based approach on the non-clinical development of ATMPs, two questions are addressed in this paper. Firstly, “Do companies use a risk-based approach for the non-clinical development of ATMPs?” and, secondly, “Does the Committee for Medicinal Products for Human Use (CHMP) of the European Medicines Agency (EMA) accept non-clinical development programs based on the risk-based approach?” Scientific advice letters formulated by the CHMP were analyzed. The risk-based approach was used to justify deviations from the guidelines in the majority (75%) of the cases. The CHMP accepted 40% of the proposals to omit studies and stated that additional data was necessary to make an informed decision for 35% of the proposals. This indicates that the risk-based approach facilitates the science-driven development of ATMPs.  相似文献   

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The present study examined effects of caffeine on antinociception by acetaminophen in the formalin test in mice. It demonstrates that caffeine 10mg/kg inhibits antinociception produced by acetaminophen 300 mg/kg i.p. against phase 2 flinches. Chronic administration of caffeine in the drinking water (0.1, 0.3g/l) for 8 days also inhibits the action of acetaminophen. The selective adenosine A(1) receptor antagonist DPCPX 1mg/kg i.p. mimics the action of caffeine, but the selective adenosine A(2A) receptor antagonist SCH58261 3mg/kg i.p. does not. While acetaminophen produced the same effect in mice that were +/+, +/- and -/- for adenosine A(1) receptors, inhibition of antinociception by caffeine was seen only in +/+ and +/- mice. A higher dose of caffeine, 40 mg/kg, produced an intrinsic antinociception against formalin-evoked flinches, an effect also seen when caffeine was administered intrathecally. SCH58261 30 nmol, but not DPCPX 10 nmol, also produced antinociception when administered intrathecally indicating involvement of adenosine A(2A) receptors in spinal antinociception. Caffeine reversal of acetaminophen results from actions in the spinal cord, as intrathecal DPCPX 10 nmol inhibited antinociception by systemic acetaminophen; this was also observed in +/+ but not in -/- adenosine A(1) receptor mice. We propose that spinal adenosine A(1) receptors contribute to the action of acetaminophen secondarily to involvement of descending serotonin pathways and release of adenosine within the spinal cord. Inhibition of acetaminophen antinociception by doses of caffeine relevant to dietary human intake levels suggests a more detailed consideration of acetaminophen-caffeine interactions in humans is warranted.  相似文献   

19.
Rapid detoxification of heroin dependence by buprenorphine   总被引:3,自引:1,他引:2  
评价丁丙诺啡7-8d递减法治疗海洛因戒断症状(戒毒)的临床疗效.方法:60例海洛因成瘾者根据依赖程度分为三组,分别给予低、中、高三种剂量丁丙诺啡舌下含服片剂治疗.治疗期间患者戒断症状采用“美国临床研究所麻醉药品评价量表”评价;对海洛因的心理渴求采用“视觉类比量表”自评;丁丙诺啡副作用采用“副反应量表”评价.结果:三组戒毒患者丁丙诺啡平均日消耗量分别为20,29和36mg.此剂量的丁丙诺啡不仅可有效地控制海洛因戒断症状,且可缩短戒毒时程.结论:丁丙诺啡是一个有希望替代纯阿片受体激动剂的有效、快速戒毒药物.  相似文献   

20.
Mice were trained to avoid electric shock (0.6 mA) in a step-through type passive avoidance learning task, retention being measured 24 h after the training trial. Morphine 10 mg/kg administered 30 min before the test trial (pretest) facilitated memory retrieval, and the effect was completely antagonized by 1 mg/kg naloxone, a selective -opioid receptor antagonist. On the other hand, pretest administration of 0.01–10 mg/kg DTLET, a selective -opioid receptor agonist, did not produce the same effect as morphine. Nor-binaltorphimine, a -opioid receptor antagonist, did not antagonize the effect of pretest morphine, at doses of 1 and 2 mg/kg. These results suggest that the facilitation of memory retrieval by pretest morphine is mediated through - but not - or -opioid receptors.  相似文献   

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