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101.

Objective

Hypertonic saline (HTS) has potent immune and vascular effects. We assessed recipient pretreatment with HTS on allograft function in a porcine model of heart transplantation and hypothesized that HTS infusion would limit endothelial and left ventricular (LV) dysfunction following transplantation.

Methods

Heart transplants were performed after 6 hours of cold ischemic storage. Recipient pigs were randomized to treatment with or without HTS (7.5% NaCl) before cardiopulmonary bypass (CPB). Using a myograft apparatus, coronary artery endothelial-dependent (Edep) and -independent (Eind) relaxation was assessed. LV performance was determined using pressure-volume loop analysis. Pulmonary interleukin (IL)-2, IL-6, and tumor necrosis factor (TNF)-α expression was measured.

Results

Weaning from CPB and LV performance after transplantation were improved in HTS-treated animals. Successful weaning from CPB was greater in the HTS-treated hearts (8 of 8 vs 2 of 8; P < .05). Mean LV functional recovery was improved in the HTS-treated animals, as assessed by preload recruitable stroke work (65 ± 10% vs 27 ± 10%; P < .001) and end-systolic elastance (55 ± 7% vs 37 ± 4%; P < .001). Treatment with HTS resulted in improved Edep (mean maximum elastance [Emax], 56 ± 5% vs 37 ± 7%; P < .001) and Eind (mean Emax%, 77 ± 6% vs 52 ± 4%; P < .001) vasorelaxation compared with control. Pulmonary expression of IL-2, IL-6, and TNF-α increased following transplantation, whereas HTS therapy attenuated IL production (P < .001). Transplantation increased plasma TNF-α levels and LV TNF-α expression, whereas HTS prevented this up-regulation (P < .001).

Conclusions

Recipient HTS pretreatment preserves allograft vasomotor and LV function, and HTS therapy limits CPB-induced injury. HTS may be a novel recipient intervention to prevent graft dysfunction.  相似文献   
102.
目的 采用网络药理学阐明济脉通片多成分-多靶点-多途径的作用理念,为进一步研究济脉通片降压药效物质基础和机制提供一定理论参考。方法 通过TCMSP数据库,结合口服利用度(≥ 30%)和类药性分析(≥ 0.18)参数,筛选济脉通片的活性成分;通过Drugbank和TCMSP数据库进行靶点预测分析;通过GENCARD数据库筛选出高血压疾病相关基因;结合DAVID和KEGG数据库进行GO分析和通路分析;使用Cystoscope软件构建"化合物-靶点-作用通路"网络图。结果 经筛选后得到济脉通片的33个化合物,148个潜在靶基因并映射到了223条信号通路,其中31条信号通路与高血压的发生发展密切相关,其中AGE-RAGE signaling pathway in diabetic complications、PI3K-Akt signaling pathway、TNFsignaling pathway、Adrenergic signaling in cardiomyocytes和Focal adhesion为重要的通路枢纽。结论 济脉通片主要通过多成分、多靶点、多通路调节血管内皮功能、炎症反应、钙钠离子转运、糖脂代谢等参与血管舒张、改善炎症、调节机体代谢、调节离子转运等而产生降压作用。  相似文献   
103.
目的:建立液相色谱-串联质谱法(UPLC-MS/MS)同时测定人血浆中头孢哌酮与舒巴坦的浓度,分析头孢哌酮/舒巴坦血药浓度监测结果,为临床合理用药提供参考。方法:以氯唑沙宗为内标,采用Waters BEHC18柱(2.1 mm×100 mm,1.7 μm)进行分离,通过串联质谱仪,负离子检测模式下,以多反应监测(MRM)方式进行定量测定。对某院2018年以不同给药方案进行治疗的73例住院患者测定的头孢哌酮/舒巴坦血药浓度结果进行分析。结果:头孢哌酮与舒巴坦在测定条件下1~200 mg·L-1范围内线性关系良好,两者日内精密度RSD均<10%,基质效应分别为(72.77±0.99)%与(75.72±0.11)%,提取回收率均>90%。73例患者共监测血药浓度96次,其中不同给药方案2 g,q8 h(43例次);2 g,q12 h(26例次);2 g,q6 h(27例次),各组头孢哌酮血药浓度的中位数分别为34.12 mg·L-1(4.12~177.79 mg·L-1)、31.23 mg·L-1(1.89~251.8 mg·L-1)、59.96 mg·L-1(1.77~140.58 mg·L-1),舒巴坦血药浓度的中位数分别为6.3 mg·L-1(0.61~136.01 mg·L-1)、28.83 mg·L-1(0.5~133.69 mg·L-1)、11.17 mg·L-1(0.73~143.53 mg·L-1)。Mann-Whitney U检验显示,头孢哌酮血药浓度结果无统计学差异(P>0.05),舒巴坦有统计学差异(P<0.05)。结论:本检测方法操作简便、快速、重复性好,可满足临床头孢哌酮与舒巴坦浓度的检测;头孢哌酮/舒巴坦在不同给药方案下血药浓度结果与个体差异相关,有必要开展血药浓度监测并依据结果适时调整用药方案,提高治疗效果减少耐药率的发生。  相似文献   
104.
The purpose of this study was to elucidate the involvement of Mate1 in the tubular secretion of trimethoprim and saturation of Mate1-mediated efflux to address the mechanisms underlying the pharmacokinetic drug interactions with trimethoprim. Trimethoprim is a more potent inhibitor of MATE2-K than MATE1 with Ki values (μM) of 0.030–0.28 and 2.4–5.9, respectively. Trimethoprim is a substrate of human MATE1 and MATE2-K with Km values of 2.3 ± 0.9 and 0.018 ± 0.004 μM, and mouse Mate1, but not human OCT2, mouse Oct1 and Oct2. Pyrimethamine significantly reduced the renal clearance (CLR) of trimethoprim (mL/min/kg) from 40.0 ± 5.1 to 20.1 ± 3.7 (p < 0.05). Trimethoprim was given to mice at three infusion rates (150, 500, and 1500 nmol/min/kg). Together with an increase in the plasma concentrations of trimethoprim, the CLR (mL/min/kg) of trimethoprim decreased to 25.9 ± 3.2, 13.5 ± 5.7, and 8.92 ± 1.50 at the respective rates. Trimethoprim decreased the CLR of rhodamine 123 in an infusion rate-dependent manner: 11.5 ± 1.3 (control), 5.17 ± 1.55, 1.31 ± 0.50, and 0.532 ± 0.180. These results suggest that Mate1 mediates the tubular secretion of trimethoprim, and at therapeutic doses, MATEs-mediated efflux can be saturated, and thereby, cause drug interactions with other MATE substrates.  相似文献   
105.
Introduction: Research on medication use aims at assessing how much of current pharmacotherapy is rational. In neonates, this is hampered by extensive off-label drug use and limited knowledge.

Areas covered: We report on medication use research and have conducted a systematic review of observational studies on medication use to provide an updated overview on characteristics, objectives, methods, and patterns in hospitalized neonates. Moreover, a review on aspects of medication use for opioids, anti-epileptics, gastric acid-related disorders and respiratory stimulants with emphasis on trends and impact of interventions is presented, illustrating how research on medication use can contribute to improved neonatal pharmacotherapy and more focused research. Medication use reports describe patterns and provide signals on irrational use, benchmarking, or can guide research priorities. Moreover, this may generate information on how neonatal health topics and their pharmacotherapy are handled over time or across regions.

Expert opinion: Research on medicine utilization is relevant, since it will inform us on aspects like trends, variability, or about the impact and pattern of implementation of guidelines in neonates. Further progress necessitates to merge datasets on medication use with clinical characteristics, and perinatal drug use remains an area in need of additional research.  相似文献   

106.
BackgroundIn the phase III CASTOR study in relapsed or refractory multiple myeloma, daratumumab, bortezomib, and dexamethasone (D-Vd) demonstrated significant clinical benefit versus Vd alone. Outcomes after 40.0 months of median follow-up are discussed.Patients and MethodsEligible patients had received ≥ 1 line of treatment and were administered bortezomib (1.3 mg/m2) and dexamethasone (20 mg) for 8 cycles with or without daratumumab (16 mg/kg) until disease progression.ResultsOf 498 patients in the intent-to-treat (ITT) population (D-Vd, n = 251; Vd, n = 247), 47% had 1 prior line of treatment (1PL; D-Vd, n = 122; Vd, n = 113). Median progression-free survival (PFS) was significantly prolonged with D-Vd versus Vd in the ITT population (16.7 vs. 7.1 months; hazard ratio [HR], 0.31; 95% confidence interval [CI], 0.25-0.40; P < .0001) and the 1PL subgroup (27.0 vs. 7.9 months; HR, 0.22; 95% CI, 0.15-0.32; P < .0001). In lenalidomide-refractory patients, the median PFS was 7.8 versus 4.9 months (HR, 0.44; 95% CI, 0.28-0.68; P = .0002) for D-Vd (n = 60) versus Vd (n = 81). Minimal residual disease (MRD)–negativity rates (10−5) were greater with D-Vd versus Vd (ITT: 14% vs. 2%; 1PL: 20% vs. 3%; both P < .0001). PFS2 was significantly prolonged with D-Vd versus Vd (ITT: HR, 0.48; 95% CI, 0.38-0.61; 1PL: HR, 0.35; 95% CI, 0.24-0.51; P < .0001). No new safety concerns were observed.ConclusionAfter 3 years, D-Vd maintained significant benefits in patients with relapsed or refractory multiple myeloma with a consistent safety profile. D-Vd provided the greatest benefit at first relapse and increased MRD-negativity rates.  相似文献   
107.
目的 探讨接受新辅助放化疗的局部晚期食管鳞癌患者新辅助放疗剂量与病理完全缓解(pCR)的关系。方法 收集2017-2019年间在四川大学华西医院肿瘤中心经病理确诊为食管鳞癌并接受新辅助放化疗和手术的 116例局部晚期患者临床资料。116例患者中 40~45Gy组 80例,≥45Gy组 36例,分析两组术后pCR率。结果 全组患者的pCR率为38.8%(45/116),40~45Gy组与≥45Gy组的pCR率分别为44%(35/80)和28%(10/36)(P=0.105)。结论 术前新辅助采用较高的放疗剂量不增加局部晚期食管鳞癌的pCR率,有必要进行前瞻性的临床研究确定合适的新辅助放疗剂量。  相似文献   
108.
109.
The inflammatory response induced by cardiopulmonary bypass decreases vascular tone, which in turn can lead to vasoplegic syndrome. Indeed the hypotension consequent to on-pump cardiac surgery often necessitates vasopressor and intravenous fluid support. Methylene blue counteracts vasoplegic syndrome by inhibiting the formation of nitric oxide.We report the use of methylene blue in a 75-year-old man who developed vasoplegic syndrome after cardiac surgery. After the administration of methylene blue, his hypotension improved to the extent that he could be weaned from vasopressors. The use of methylene blue should be considered in patients who develop hypotension refractory to standard treatment after cardiac surgery.  相似文献   
110.
《Brain stimulation》2020,13(5):1159-1167
BackgroundInhibitory control refers to a central cognitive capacity involved in the interruption and correction of actions. Dysfunctions in these cognitive control processes have been identified as major maintaining mechanisms in a range of mental disorders such as ADHD, binge eating disorder, obesity, and addiction. Improving inhibitory control by transcranial direct current stimulation (tDCS) could ameliorate symptoms in a broad range of mental disorders.ObjectiveThe primary aim of this pre-registered meta-analysis was to investigate whether inhibitory control can be improved by tDCS in healthy and clinical samples. Additionally, several moderator variables were investigated.MethodsA comprehensive literature search was performed on PubMed/MEDLINE database, Web of Science, and Scopus. To achieve a homogenous sample, only studies that assessed inhibitory control in the go-/no-go (GNG) or stop-signal task (SST) were included, yielding a total of 75 effect sizes from 45 studies.ResultsResults of the meta-analysis indicate a small but significant overall effect of tDCS on inhibitory control (g = 0.21) which was moderated by target and return electrode placement as well as by the task. The small effect size was further reduced after correction for publication bias.ConclusionBased on the studies included, our meta-analytic approach substantiates previously observed differences between brain regions, i.e., involvement of the right inferior frontal gyrus (rIFG) vs. the right dorsolateral prefrontal cortex (rDLPFC) in inhibitory control. Results indicate a small moderating effect of tDCS on inhibitory control in single-session studies and highlight the relevance of technical and behavioral parameters.  相似文献   
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