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61.
62.
组胺是一种具有多种生物学活性的化学介质,在体内主要由二胺氧化酶和组胺-N-甲基转移酶降解.各种原因导致的组胺代谢酶水平或活性降低及外源性组胺增加,均可引起体内组胺蓄积并产生组胺不耐受.组胺不耐受表现为一系列过敏反应样症状,涉及多个系统,食物和药物可诱发和加重这些症状.根据典型临床表现、摄入无组胺饮食或使用抗组胺药物后症状可改善、组胺双盲对照激发试验阳性、血清组胺浓度升高和二胺氧化酶活性降低可确诊组胺不耐受. 相似文献
63.
Inequalities in enrollment of women and racial minorities in trials testing uric acid lowering drugs
《Nutrition, metabolism, and cardiovascular diseases : NMCD》2021,31(12):3305-3313
AimsWe investigated sex and racial inequalities in clinical trials testing serum uric acid (SUA) lowering drugs and analyzed the temporal trends of participation among the pre-specified demographic groups.Data were collected from publications of clinical trials testing SUA-lowering drugs. Linear regression analysis was performed to assess the relation between drug approval year and proportion of women and minorities enrolled in clinical studies.Data synthesisThe mean percentage enrollment of women in clinical trials significantly decreased over the time (r = −0.43, P-value = 0.02). Moreover, there was a statistically significant difference in mean percentage enrollment of women among trials testing different SUA-lowering drugs, with the highest representation in rasburicase (71.1%) and the lowest representation of women in dotinurad (0.8%). Over the time, also the mean percentage enrollment of racial minorities decreased, passing from 8.7% to 2.2% in a 10-year period.Women were proportionally underrepresented compared with their share of the population with asymptomatic hyperuricemia, overall (participation-to-prevalence ratio (PPR) = 0.34), in trials testing xanthine oxiase inhibitors (PPR = 0.38) and uricosurics (PPR = 0.29), and in trials with febuxostat, allopurinol, pegloticase, halofenate/arhalofenate, verinurad, lesinurad and dotinurad. Women were proportionally underreppresented also compared with their share of the population with gout, overall (PPR = 0.69) and in trials testing XOIs (PPR = 0.69), uricosurics (PPR = 0.68), and all SUA-lowering drugs excepted for rasburicase, pegloticase and topiroxostat.ConclusionsOur analysis shows that women and racial and ethnical minorities are underrepresented in controlled clinical trials testing SUA-lowering drugs, with similar pattern across drug classes. 相似文献
64.
《Journal of biomaterials science. Polymer edition》2013,24(7):651-659
Freeze-thaw photopolymerization at low temperature of a mixed solution of 2-hydroxyethyl methacrylate (HEMA), ethylene glycol dimethacrylate (EDM), and either glucose oxidase (GOx) or interleukin 2 (IL-2) around frozen ice crystals has been used to generate a bead-formed macroporous hydrophilic matrix with potential for immobilization and sustained release. The mean equilibrium acetate buffer content (EBC) of unloaded p-HEMA beads at room temperature and controlled humidity was ~72%. The incorporation of GOx into beads significantly increased the EBC to ~76%. The release of GOx was characterized by a short initial burst release which declined rapidly until by day 14 no further biologically active enzyme release could be detected. Bead size had no significant effect on the total mean cumulative release of GOx at room temperature. Since only ~ 4% of the original therapeutic load of GOx was released over 14 days a substantial proportion of biologically active enzyme had become associated with the hydrogel matrix surface generating a bead formed immobilised enzyme system. Total cumulative release profiles for IL-2 were almost linear and maintained for at least 16 days. In absolute terms, the proportion of the original theoretical incorporated load subsequently released over this period was low. However, such a low level sustained release of IL-2 may lend itself therapeutically to a reduction in unwanted non-specific systemic activity. 相似文献
65.
《Connective tissue research》2013,54(1-2):1-2
The effects of various avocado oils on collagen metabolism in skin were studied in growing rats fed diets containing 10% (w/w) of the tested oils. Rats fed the unrefined avocado oil extracted with hexane from the intact fruit, its unsaponifiables or the avocado seed oil, showed significant increases in soluble collagen content in skin, though total collagen content was not affected. The increased soluble collagen content appears to be a consequence of the inhibition of lysyl oxidase activity. The active factor was found to be present in the unrefined avocado oil and probably originated from the avocado seed, since collagen metabolism was affected only by fractions which contained lipids fraction from the seed. In comparison rats fed the refined or unrefined soybean oils showed no effects. 相似文献
66.
《Expert opinion on investigational drugs》2013,22(7):1115-1125
Background: Dopamine replacement therapies (levodopa, dopamine receptor agonists, anticholinergics, monoamine oxidase B inhibitors, and catechol-O-methyltransferase inhibitors) remain the cornerstones of therapeutic interventions for Parkinson's disease (PD). Despite the treatment options for PD symptoms, a cure remains elusive. An optimal treatment would be one that combined relief in both motor and nonmotor symptoms with neuroprotective properties. Safinamide is an investigational drug for PD currently in development as add-on therapy to both dopamine agonists and levodopa. Safinamide is a unique molecule with a novel mode of action, targeting both dopaminergic and glutaminergic systems, and potentially provides motor symptom control. Preliminary results from experimental models suggest potential neuroprotective effects. Studies on the potential effects on nonmotor symptoms are ongoing. Objective: To review the mechanism of action and pharmacokinetics, and to evaluate the available clinical safety and efficacy results of safinamide. Methods: A search of the electronic database MEDLINE (PubMed, no time limits) was performed on 14 December 2007. The full text of all citations was obtained for review. Furthermore, two abstracts on safinamide published as proceedings of a European conference were reviewed. Results/conclusion: Safinamide is a promising investigational drug for PD with a novel mode of action. Early reports confirm the potential efficacy of safinamide in PD. Further studies on potential effects on cognition and neuroprotection are needed. 相似文献
67.
Yueting Deng Chen Huang Jingyue Su Chen-Wei Pan Chaofu Ke 《Nutrition, metabolism, and cardiovascular diseases : NMCD》2021,31(2):382-395
AimEssential hypertension (EH) is one of the most important public health problems worldwide. However, the pathogenesis of EH is unclear and early diagnostic methods are lacking. Metabolomics demonstrates great potential for biomarker discovery and the mechanistic exploration of metabolic diseases.Data synthesisThis review included human and animal metabolomics studies related to EH in the PubMed and Web of Science databases between February 1996 and May 2020. The study designs, EH standards, and reported metabolic biomarkers were systematically examined and compared. The pathway analysis was conducted through the online software MetaboAnalyst 4.0.Twenty-two human studies and fifteen animal studies were included in this systematic review. There were many frequently reported biomarkers with consistent trends (e.g., pyruvate, lactic acid, valine, and tryptophan) in human and animal studies, and thus had potential as biomarkers of EH. In addition, several shared metabolic pathways, including alanine, aspartate, and glutamate metabolism, aminoacyl-tRNA biosynthesis, and arginine biosynthesis, were identified in human and animal metabolomics studies. These biomarkers and pathways, closely related to insulin resistance, the inflammatory state, and impaired nitric oxide production, were demonstrated to contribute to EH development.ConclusionsThis study summarized valuable metabolic biomarkers and pathways that could offer opportunities for the early diagnosis or prediction of EH and the discovery of the metabolic mechanisms of EH. 相似文献
68.
69.
心肌雷诺定受体2是一种心肌细胞钙释放通道,对心肌Ca2+循环起着至关重要的作用。该受体的功能受心肌钙调控蛋白FKBP12.6、SERCA2a和CASQ2等的影响,而此类蛋白的表达又与内皮素-NADPH氧化酶(ET-NOX)途径有关。ET-NOX途径和心肌钙调控蛋白的异常均会导致心律失常和心衰。因此,ET-NOX途径中各成员以及心肌钙调控蛋白有可能成为治疗心律失常和心衰的新靶标。综述了心肌钙调控蛋白和ET-NOX途径在正常心肌兴奋收缩耦联过程及病理过程中的作用,并介绍了相关的在研抗心律失常药物。 相似文献
70.
《Renal failure》2013,35(8):1124-1129
AbstractObjective: The objective of this study is to evaluate the effect and mechanism of mitochondria-targeted peptides (MTP131 and SPI20) on contrast-induced acute kidney injury (CI-AKI) in rats with hypercholesterolemia. Method: Forty SD rats were randomly divided into normal diet group (NN, n?=?8) and high cholesterol supplemented dietary group (HN, n?=?32). At the end of 8 weeks, the group HN was divided into four subgroups. All Rats were given injection of either diatrizoate (10?mL/kg) or equal volume of normal saline, the rats pretreated with MTP131 or SPI20 were given injection with MTP131 or SPI 20 (3?mg/kg) by peritoneal cavity for 3 times. Blood, urine and renal tissue samples were prepared to determine biochemical parameters. The renal pathological changes were evaluated by hematoxylin and eosin staining and scored semiquantitatively, The protein expression of renal NOX4 was also measured by Western blotting. Results: In diatrizoate-injected rats, Serum creatinine (Scr), fractional excretion of sodium (FeNa%), fractional excretion of potassium (FeK%), pathological scores, renal malondialdehyde (MDA) content, the NADPH oxidase activity and the expression of NOX4 in kidney tissue were significantly increased (p?<?0.01). In the groups pretreated with MTP131 or SPI20, the levels of Scr, FeNa%, FeK%, MDA content and NADPH oxidase activity in renal tissue decreased (p?<?0.01), the levels of renal super oxygen dehydrogenises and ATPase activity increased (p?<?0.01). The renal injuries induced by contrast media (CM) were alleviated. Conclusion: MTP131 and SPI20 might protect acute kidney injury induced by CM in rats with hypercholesterolemia. 相似文献