Dose response

剂量反应
  • 文章类型: Journal Article
    在作物上使用除草剂往往会导致无意中,低剂量暴露于非目标生物,比如昆虫。虽然人们越来越知道这些暴露会改变昆虫的生存和生理,目前尚不清楚这些影响是否会在人群之间有所不同,并改变其他与健身相关的特征,比如行为和免疫力。这里,我们通过测试亚致死性暴露于草甘膦除草剂(GBH)对来自六个自然种群的欧洲雄性雄性的行为和免疫力的影响来解决这些问题。我们将每个雄性暴露于推荐用于农作物的普通GBH(Roundup©)剂量,比作物建议的低五倍,或控制解决方案。二十四小时后,我们测量了活动,大胆,和每个男性的聚集。然后我们将它们暴露在昆虫病原真菌中,监测他们的存活6周,并测量了幸存者的免疫反应。我们发现GBH暴露对男性活动的条件依赖性影响。暴露于低剂量诱导活动和体重之间的正相关,在高剂量组和对照组中未观察到。然而,GBH对任何其他测量性状均无影响。所有这些结果在测试的六个人群中都是一致的,尽管我们确实在几乎所有男性的测量中发现了特定人群的差异。现在需要进一步的研究来更好地了解GBH对男性活动的剂量反应及其生物学影响,以及评估该物种解毒过程的有效性。总的来说,这些结果强调了研究除草剂对昆虫的影响的重要性,以扩大我们对综合虫害管理计划中植物保护产品的使用和潜在风险的一般理解。
    The use of herbicides on crops often results in unintentional, low-dose exposure of non-target organisms, such as insects. While these exposures are increasingly known to alter the survival and physiology of insects, it remains unclear whether these effects can vary between populations and modify other fitness-related traits, such as behaviour and immunity. Here, we addressed these questions by testing the effects of sublethal exposure to a glyphosate-based herbicide (GBH) on the behaviour and immunity of European earwig males from six natural populations. We exposed each male to a dose of a common GBH (Roundup©) that was either recommended for crops, five times lower than that recommended for crops, or to a control solution. Twenty-four hours later, we measured the activity, boldness, and aggregation of each male. We then exposed them to an entomopathogenic fungus, monitored their survival for 6 weeks, and measured the immune response of the survivors. We found a condition-dependent effect of GBH exposure on male activity. Exposure to low doses induced a positive association between activity and weight, which was not observed in the high-dose and control groups. However, GBH had no effect on any of the other measured traits. All these results were consistent across the six populations tested, although we did find population-specific differences in almost all measurements on males. Further research is now needed to better understand the dose-response to GBH on male activity and its biological impact, as well as to evaluate the effectiveness of detoxification processes in this species. Overall, these results emphasise the importance of investigating the effects of herbicides on insects to expand our general understanding of the use and potential risks of plant protection products in integrated pest management programs.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    目的:本研究旨在通过meta分析的系统评价来描述每日步数与全因死亡率的相关性估计值的变异性。为了确定可能造成这种情况的因素,并提供最新的估计。
    方法:截至2024年5月,系统搜索了5个数据库,以通过荟萃分析和前瞻性队列研究确定系统评价。对以前的综述进行了定性综合,并对队列研究进行了更新的荟萃分析。使用随机效应模型计算集合风险比(HR)及其95%置信区间(CI)。
    结果:纳入了11项系统综述和荟萃分析和14项队列研究,揭示了结果呈现的相当大的可变性。我们更新的荟萃分析显示出非线性关联,表明随着每日步数的增加,全因死亡率的风险较低,保护阈值为3143步/天,每1000步/天增量的合并HR为0.91(95%CI:0.87,0.95)。身体活动类别一致表明死亡风险逐渐降低,高活性类别(>12,500步/天)表现出最低风险(0.35(95%CI:0.29,0.42))。
    结论:系统评价和荟萃分析显示,由于定量暴露的方法不同,效果估计存在相当大的差异。尽管如此,我们的研究强调了增加每日步骤对降低全因死亡率的重要性,最低保护剂量为3000步/天,尽管最佳剂量因年龄和性别而异。建议未来的研究按身体活动类别对每日步数进行分类,进行剂量反应分析,并使用1000步/天的增量。
    OBJECTIVE: This study aimed to describe the variability in estimates of the association of daily steps and all-cause mortality in systematic reviews with meta-analyses, to identify the factors potentially responsible for it, and to provide an updated estimate.
    METHODS: Five databases were systematically searched up to May 2024 to identify systematic reviews with meta-analyses and prospective cohort studies. A qualitative synthesis of previous reviews and an updated meta-analysis of cohort studies were performed. Pooled hazard ratios (HRs) with their 95% confidence intervals (CIs) were calculated using a random-effects model.
    RESULTS: Eleven systematic reviews with meta-analyses and 14 cohort studies were included, revealing considerable variability in result presentation. Our updated meta-analysis showed a nonlinear association, indicating a lower risk of all-cause mortality with increased daily steps, with a protective threshold at 3143 steps/day, and a pooled HR of 0.91 (95% CI: 0.87, 0.95) per 1000 steps/day increment. Physical activity categories consistently indicated progressively reduced mortality risk, with the highly active category (>12,500 steps/day) exhibiting the lowest risk (0.35 (95% CI: 0.29, 0.42)).
    CONCLUSIONS: Systematic reviews and meta-analyses showed considerable variability in effect estimates due to different methods of quantifying exposure. Despite it, our study underscores the importance of increased daily steps in reducing all-cause mortality, with a minimum protective dose of 3000 steps/day, although the optimal dose differed according to age and sex. It is recommended that future studies categorise daily steps by physical activity category, perform dose-response analyses, and use increments of 1000 steps/day.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    在寻找减缓许多与年龄相关的疾病/病症的发作和降低其严重程度的活性/药剂方面已经存在大量的研究兴趣。这项评估表明,在广泛疾病的人群调查中,旨在促进健康的研究最多的药物是他汀类药物,大规模流行病学研究解决了许多健康终点。关键发现是,他汀类药物治疗可持续减少多种非传染性和传染性疾病的发生并减轻多种癌症的进程,高死亡率约为20-50%。一种药物可能会影响流行病学研究中如此广泛且持续的积极趋势,这是出乎意料且令人印象深刻的,以及一致的细胞和动物模型研究。已经提出了潜在的机制,显着有助于他汀类药物的有益作用谱,特别是激活Nrf2的能力,在多种器官和细胞类型中显示出剂量反应,由于其生物利用度和广泛的组织分布。他汀类药物的广泛使用,它有能力提高人类的健康跨度,作为一种新的公共卫生策略,应考虑进行实验探索,其中包括减少此类药物最常见不良反应的实用方法,包括肌痛/肌病和转羊炎。
    There has been substantial research interest in finding activities/agents that slow the onset and reduce the severity of numerous age-related diseases/conditions. This assessment indicates that the most studied agent intended to promote health in human population investigations for a broad spectrum of diseases are the statins, with large-scale epidemiological studies addressing numerous health endpoints. The key findings are that statin treatment consistently reduces the occurrence and attenuates the course of numerous non-communicable and contagious pathologies and numerous types of cancer with high mortality rates by about 20-50%. That one agent could affect such a broad based and consistently positive trends in epidemiological studies is unexpected and impressive, along with consistent cell and animal model research. Underlying mechanisms have been proposed that significantly contribute to the spectrum of salutary effects of statins, especially the capacity to activate Nrf2 showing hormetic dose responses in multiple organs and cell types, due to its bioavailability and broad tissue distribution. The widespread use of statins, which has the capacity to enhance human health span, should be considered for experimental exploration as a novel public health strategy that includes practical approaches for reduction of the most common adverse effects of this class of drugs including myalgia/myopathy and transaminitis.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    在临床环境中使用的许多治疗和诊断方法取决于通过全身递送施用化合物。纳米尺度的生物材料,作为树枝状聚合物,通过提高货物的生物利用度作为输送系统,循环时间,和特定组织的靶向。尽管评估基于纳米材料的药物的功效至关重要,对生物材料进行毒理学评估对于推进临床转化至关重要。这里,探索了斑马鱼幼虫模型来评估聚(酰胺基胺)(PAMAM)的生物相容性,用于药物递送的最受欢迎的树枝状聚合物之一。我们报告了全身注射聚乙二醇(PEG)修饰的G4PAMAM结合罗丹明(Rho)作为模拟药物(PEG-PAMAM-Rho)对存活率的影响,动物发育,炎症,和神经毒性。观察到对死亡率的浓度和时间依赖性影响,发育形态学,和先天免疫系统激活(巨噬细胞)。早在注射后48小时,最高测试浓度(50mg/mLPEG-PAMAM-Rho)就报告了毒理学指标的显着影响。此外,发现较低浓度的PEG-PAMAM-Rho(5mg/mL)是安全的,随后通过行为学试验检测了其神经毒性.InAccording,没有检测到明显的毒性迹象。总之,评估动物的剂量反应,并确定了将来用于治疗诊断的安全剂量。此外,建立了新的方法,可以适应使用其他纳米系统进行全身给药的毒理学的进一步研究。
    Numerous therapeutic and diagnostic approaches used within a clinical setting depend on the administration of compounds via systemic delivery. Biomaterials at the nanometer scale, as dendrimers, act as delivery systems by improving cargo bioavailability, circulation time, and the targeting of specific tissues. Although evaluating the efficacy of pharmacological agents based on nanobiomaterials is crucial, conducting toxicological assessments of biomaterials is essential for advancing clinical translation. Here, a zebrafish larvae model was explored to assess the biocompatibility of poly(amido amine) (PAMAM), one of the most exploited dendrimers for drug delivery. We report the impact of a systemic injection of polyethylene glycol (PEG)-modified G4 PAMAM conjugated with rhodamine (Rho) as a mimetic drug (PEG-PAMAM-Rho) on survival, animal development, inflammation, and neurotoxicity. A concentration- and time-dependent effect was observed on mortality, developmental morphology, and innate immune system activation (macrophages). Significant effects in toxicological indicators were reported in the highest tested concentration (50 mg/mL PEG-PAMAM-Rho) as early as 48 h post-injection. Additionally, a lower concentration of PEG-PAMAM-Rho (5 mg/mL) was found to be safe and subsequently tested for neurotoxicity through behavioral assays. In accordance, no significative signs of toxicity were detected. In conclusion, the dose response of the animal was assessed, and the safe dosage for future use in theragnostics was defined. Additionally, new methodologies were established that can be adapted to further studies in toxicology using other nanosystems for systemic delivery.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    暂无摘要。
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    他汀类药物可降低低密度脂蛋白胆固醇(LDL-C),可有效预防动脉粥样硬化性心血管疾病(ASCVD)。他汀类药物的剂量反应因患者而异,可以使用三种不同的药理学特性进行建模:(1)E0(基线LDL-C),(2)ED50(效力:实现LDL-C降低50%的中值剂量);和(3)Emax(功效:最大LDL-C降低)。然而,个体化剂量反应及其与ASCVD事件的关联尚不清楚.
    我们分析了ED50和Emax与真实世界心血管疾病结局之间的关系。
    我们利用去识别的电子健康记录数据来识别暴露于多剂量三种最常用的他汀类药物(阿托伐他汀,辛伐他汀,或瑞舒伐他汀)在其纵向医疗保健的背景下。我们推导了ED50和Emax来量化与ASCVD事件和全因死亡率的复合结局的关系。
    我们估计了3,033个独特个体的ED50和Emax(阿托伐他汀:1,632,辛伐他汀:1,089和瑞舒伐他汀:312)使用非线性,混合效应剂量-反应模型。事件时间分析显示ED50和Emax与主要终点独立相关。危险比为0.85(p<0.01),0.83(p<0.01),ED50和1.13(p<0.001)为0.87(p=0.10),1.06(p<0.001),阿托伐他汀的Emax为1.15(p=0.009),辛伐他汀,和瑞舒伐他汀队列,分别。
    ED50和Emax与临床结局的全类关联表明,这些指标影响他汀类药物患者发生ASCVD事件的风险。
    UNASSIGNED: Statins reduce low-density lipoprotein cholesterol (LDL-C) and are efficacious in the prevention of atherosclerotic cardiovascular disease (ASCVD). Dose-response to statins varies among patients and can be modeled using three distinct pharmacological properties: (1) E0 (baseline LDL-C), (2) ED50 (potency: median dose achieving 50% reduction in LDL-C); and (3) Emax (efficacy: maximum LDL-C reduction). However, individualized dose-response and its association with ASCVD events remains unknown.
    UNASSIGNED: We analyze the relationship between ED50 and Emax with real-world cardiovascular disease outcomes.
    UNASSIGNED: We leveraged de-identified electronic health record data to identify individuals exposed to multiple doses of the three most commonly prescribed statins (atorvastatin, simvastatin, or rosuvastatin) within the context of their longitudinal healthcare. We derived ED50 and Emax to quantify the relationship with a composite outcome of ASCVD events and all-cause mortality.
    UNASSIGNED: We estimated ED50 and Emax for 3,033 unique individuals (atorvastatin: 1,632, simvastatin: 1,089, and rosuvastatin: 312) using a nonlinear, mixed effects dose-response model. Time-to-event analyses revealed that ED50 and Emax are independently associated with the primary endpoint. Hazard ratios were 0.85 (p < 0.01), 0.83 (p < 0.01), and 0.87 (p = 0.10) for ED50 and 1.13 (p < 0.001), 1.06 (p < 0.001), and 1.15 (p = 0.009) for Emax in the atorvastatin, simvastatin, and rosuvastatin cohorts, respectively.
    UNASSIGNED: The class-wide association of ED50 and Emax with clinical outcomes indicates that these measures influence the risk for ASCVD events in patients on statins.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    肽受体放射性核素治疗提供了追踪和定量体内药物摄取并进行剂量测定的可能性,可能允许个性化的治疗方案。然而,神经内分泌肿瘤(NETs)对不同吸收剂量的反应细节尚不清楚.这里,我们在接受[177Lu]Lu-DOTATATE治疗的NETs患者队列中调查了肿瘤吸收剂量与肿瘤反应之间的关系.方法:这是一项回顾性研究,基于在临床试验中接受治疗的32例患者中的69例肿瘤。在[177Lu]Lu-DOTATATE的每个周期进行剂量测定,提供366个个体吸收剂量评估。使用[177Lu]Lu-DOTATATE进行混合平面-SPECT/CT成像,包括定量SPECT重建,基于体素的吸收剂量率计算,半自动图像分割,和部分音量校正。肿瘤体积的变化用于确定肿瘤反应。在连续的CT扫描中手动描绘每个肿瘤的体积,给出总共712个个体肿瘤体积评估。根据分级对肿瘤进行分层。使用混合效应模型和逻辑回归研究了吸收剂量与反应之间的关系。排除小于4cm3的肿瘤。结果:在2级NET中,观察到吸收剂量与体积减少之间存在明确的关系.我们的观察结果表明,对于至少135Gy的累积肿瘤吸收剂量,部分肿瘤反应的可能性为90%。结论:我们的发现与先前关于肿瘤缩小与吸收剂量之间关系的观察结果一致。此外,我们的数据提示2级NETs部分缓解的吸收剂量阈值.这些观察结果为剂量学指导的肽受体放射性核素治疗方案的设计提供了有价值的见解。
    Peptide receptor radionuclide therapy presents the possibility of tracing and quantifying the uptake of the drug in the body and performing dosimetry, potentially allowing individualization of treatment schemes. However, the details of how neuroendocrine tumors (NETs) respond to different absorbed doses are insufficiently known. Here, we investigated the relationship between tumor-absorbed dose and tumor response in a cohort of patients with NETs treated with [177Lu]Lu-DOTATATE. Methods: This was a retrospective study based on 69 tumors in 32 patients treated within a clinical trial. Dosimetry was performed at each cycle of [177Lu]Lu-DOTATATE, rendering 366 individual absorbed dose assessments. Hybrid planar-SPECT/CT imaging using [177Lu]Lu-DOTATATE was used, including quantitative SPECT reconstruction, voxel-based absorbed dose rate calculation, semiautomatic image segmentation, and partial-volume correction. Changes in tumor volume were used to determine tumor response. The volume for each tumor was manually delineated on consecutive CT scans, giving a total of 712 individual tumor volume assessments. Tumors were stratified according to grade. The relationship between absorbed dose and response was investigated using mixed-effects models and logistic regression. Tumors smaller than 4 cm3 were excluded. Results: In grade 2 NETs, a clear relationship between absorbed dose and volume reduction was observed. Our observations suggest a 90% probability of partial tumor response for an accumulated tumor-absorbed dose of at least 135 Gy. Conclusion: Our findings are in accordance with previous observations regarding the relationship between tumor shrinkage and absorbed dose. Moreover, our data suggest an absorbed dose threshold for partial response in grade 2 NETs. These observations provide valuable insights for the design of dosimetry-guided peptide receptor radionuclide therapy schemes.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    背景:Makena(己酸17-羟孕酮)于2011年在加速批准途径下被FDA批准用于预防复发性自发性早产,但未进行基本药代动力学或药效学(阶段1和阶段2)研究。当时,没有剂量-反应或浓度-反应数据.治疗浓度未知。这些数据的缺乏质疑17-羟孕酮己酸酯的给药方案是否被优化。
    目的:本研究的目的是通过分析评估己酸17-羟孕酮药理学的三个数据集来评估17-羟孕酮的给药方案:母胎医学Omega3研究,产科-胎儿药理学研究单位研究和产科-胎儿药理学研究中心研究。如果可以识别出不适当的给药方案,这些信息可以为未来的妊娠药物治疗研究提供信息。
    方法:使用Omega3研究的数据来确定血浆浓度是否与自发性早产风险相关,以及是否可以确定阈值浓度。来自产科-胎儿药理学研究单位研究的数据用于确定17-羟基孕酮己酸酯的半衰期,并开发模型以模拟各种给药方案的药物浓度。来自产科-胎儿药理学研究中心研究的数据用于确定剂量和安全性结果之间的关系。
    结果:对Omega3数据集的分析表明,随着17-羟孕酮己酸酯的对数增加,自发性早产的风险降低[比值比(95CI)0.04(0.00-0.90)]。稳态浓度>9ng/ml(相当于在25-28周时>8ng/ml)与自发性早产的最低风险相关[风险比(95CI)0.52(0.27-0.98,p=0.04)];在接受250mg每周剂量的受试者中,有25%未达到该浓度。在产科-胎儿药理学研究单位研究中,17-羟孕酮己酸酯的校正半衰期(中位数和IQR)为14.0(11.5-17.2)天.模拟表明,每周250毫克的剂量,>5每周注射需要达到9ng/ml的目标;然而,半衰期最短的那些(对应于较高的清除率),从未达到目标9ng/ml浓度。在75%的科目中,每周500mg的负荷剂量持续2周,然后每周250mg达到并在两周内保持9ng/ml的浓度,但在半衰期最短的25%中,浓度超过9ng/ml目标仅3周。在产科-胎儿药理学研究中心的研究中,所有65名接受每周500mg剂量的受试者均超过9ng/ml稳态。
    结论:己酸17-羟孕酮的给药方案不充分。药物浓度与自发性早产之间存在显著的负相关。当浓度超过9ng/ml时,风险最低,但25%接受250mg每周剂量的女性永远不会达到并保持这一浓度。该药物的长半衰期需要负荷剂量以迅速达到治疗浓度。省略确定适当剂量的基本药理学研究可能会损害17-羟基孕酮己酸酯的有效性。未来的妊娠药物治疗试验必须首先完成基础药理学研究。
    BACKGROUND: Makena (17-hydroxyprogesterone caproate) was approved by the United States Food and Drug Administration for the prevention of recurrent spontaneous preterm birth in 2011 under the accelerated approval pathway, but fundamental pharmacokinetic or pharmacodynamic (Phase 1 and Phase 2) studies were not performed. At the time, there were no dose-response or concentration-response data. The therapeutic concentration was not known. The lack of such data brings into question the dosing regimen for 17-hydroxyprogesterone caproate and if it was optimized.
    OBJECTIVE: The purpose of this study was to evaluate the dosing regimen for 17-hydroxyprogesterone by analyzing 3 data sets in which the 17-hydroxyprogesterone caproate pharmacology was evaluated, namely the Maternal-Fetal Medicine Omega 3 study, the Obstetric-Fetal Pharmacology Research Units study, and the Obstetrical-Fetal Pharmacology Research Centers study. If an inappropriate dosing regimen could be identified, such information could inform future studies of pharmacotherapy in pregnancy.
    METHODS: Data from the Omega 3 study were used to determine if plasma concentration was related to spontaneous preterm birth risk and if a threshold concentration could be identified. Data from the Obstetric-Fetal Pharmacology Research Units study were used to determine the half-life of 17-hydroxyprogesterone caproate and to develop a model to simulate drug concentrations with various dosing regimens. Data from the Obstetrical-Fetal Pharmacology Research Centers study were used to determine the relationship between dose and safety outcomes.
    RESULTS: Analysis of the Omega 3 data set indicated that the risk for spontaneous preterm birth decreased as the log concentration of 17-hydroxyprogesterone caproate increased (odds ratio, 0.04; 95% confidence interval, 0.00-0.90). A steady state concentration of >9 ng/mL (equivalent to >8 ng/mL at 25-28 weeks) was associated with the lowest risk for spontaneous preterm birth (hazard ratio, 0.52; 95% confidence interval, 0.27-0.98; P=.04); this concentration was not achieved in 25% of subjects who received the 250 mg weekly dose. In the Obstetrical-Fetal Pharmacology Research Units study, the adjusted half-life (median and interquartile range) of 17-hydroxyprogesterone caproate was 14.0 (11.5-17.2) days. Simulations indicated that with the 250 mg weekly dose, >5 weekly injections were required to reach the 9 ng/mL target; however, those with the shortest half-life (corresponding to higher clearance), never reached the targeted 9 ng/mL concentration. In 75% of subjects, a loading dose of 500 mg weekly for 2 weeks followed by 250 mg weekly achieved and maintained the 9 ng/mL concentration within 2 weeks but in those 25% with the shortest half-life, concentrations exceeded the 9 ng/mL target for only 3 weeks. In the Obstetrical-Fetal Pharmacology Research Centers study, all 65 subjects who received a weekly dose of 500 mg exceeded the 9 ng/mL steady state.
    CONCLUSIONS: The dosing regimen for 17-hydroxyprogesterone caproate was inadequate. There is a significant inverse relationship between drug concentration and spontaneous preterm birth. The risk was lowest when the concentration exceeded 9 ng/mL, but 25% of women who received the 250 mg weekly dose never reached or maintained this concentration. The drug\'s long half-life necessitates a loading dose to achieve therapeutic concentrations rapidly. The omission of basic pharmacologic studies to determine the proper dosing may have compromised the effectiveness of 17-hydroxyprogesterone caproate. Future pharmacotherapy trials in pregnancy must first complete fundamental pharmacology studies.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    通过分析现有文献数据,在γ射线剂量的扩展范围内检查体外细胞遗传学剂量反应的线性二次(LQ)模型的失真,并建立剂量范围,其中LQ剂量反应曲线(DRC)可以最准确地拟合生物剂量测定。
    从108个开放来源中提取了急性γ射线在人淋巴细胞中体外诱导的双中心(Dic)或双中心加中心环(DicCR)产量的数据。将剂量范围高达50Gy的总剂量反应数据集拟合到分数理性(FR)模型,其中在分子中包含一个\'基本\'LQ函数,和取决于分母中剂量的平方的减少因子。在Grigoriev医学放射学研究所获得的细胞遗传学剂量反应数据,哈尔科夫,乌克兰(GIMRO)在0.1-20.3Gy的急性γ射线范围内拟合到LQ模型,并逐渐变化最小或最大辐射剂量。
    总体剂量反应,正如预期的那样,遵循剂量范围≤5Gy的LQ函数,但是在延长的剂量范围内似乎是S形的,在剂量≥22Gy时具有强烈的饱和度和平台。FR模型中的“基本”LQ方程的系数与许多已发表的DRC非常接近;计算的渐近线为17。将GIMRO数据集拟合到LQ模型,随着剂量范围的变化,线性系数随着最小或最大辐射剂量的增加而增加。而二次系数的下降主要受最高剂量增加的调节。最好的健康,通过较低的χ2值评估,发生剂量范围0.1-1.0Gy;0.5-5.9Gy;1.0-7.8Gy;2.0-9.6Gy,3.9-16.4Gy和5.9-20.3Gy。通过重新拟合其他实验室发布的数据集,证实了LQ系数变化的“看到”效应。
    由于剂量反应的饱和,具有固定系数的经典LQ模型似乎对辐射剂量>5Gy的细胞遗传学剂量测定具有有限的适用性。在DRC构建过程中,必须考虑LQ系数对剂量范围变化的不同响应。在校准实验中正确选择最小和最大剂量可以提高LQDRC的拟合优度。
    UNASSIGNED: To examine the distortion of the linear quadratic (LQ) model of in vitro cytogenetic dose response over an extended range of γ-ray doses by analyzing the available literature data, and to establish the dose ranges, in which the LQ dose response curve (DRC) can be most accurately fitted for biological dosimetry.
    UNASSIGNED: Data on yields of dicentrics (Dic) or dicentrics plus centric rings (Dic + CR) induced in vitro in human lymphocytes by acute γ-rays were extracted from 108 open sources. The overall dose response dataset in the dose range up to 50 Gy was fitted to a fractional-rational (FR) model, which included a \'basic\' LQ function in the numerator, and a reduction factor dependent on the square of the dose in the denominator. Cytogenetic dose response data obtained at Grigoriev Institute for Medical Radiology, Kharkiv, Ukraine (GIMRO) in the range 0.1 - 20.3 Gy acute γ-rays were fitted to the LQ model with the progressive changing minimum or maximum radiation dose.
    UNASSIGNED: The overall dose response, as expected, followed the LQ function in the dose range ≤5 Gy, but in the extended dose range appeared to be S-shaped, with intensive saturation and a plateau at doses ≥22 Gy. Coefficients of the \'basic\' LQ equation in FR model were very close to many published DRCs; calculated asymptote was 17. Fitting of the GIMRO dataset to the LQ model with the shift of the dose range showed the increase in linear coefficient with the increment of either minimum or maximum radiation dose, while the decline of the quadratic coefficient was regulated mostly by the increase of the highest dose. The best goodness of fit, assessed by lower χ2 values, occurred for dose ranges 0.1 - 1.0 Gy; 0.5 - 5.9 Gy; 1.0 - 7.8 Gy; 2.0 - 9.6 Gy, 3.9 - 16.4 Gy and 5.9 - 20.3 Gy. The \'see-saw\' effect in changes of LQ coefficients was confirmed by re-fitting datasets published by other laboratories.
    UNASSIGNED: The classical LQ model with fixed coefficients appears to have limited applicability for cytogenetic dosimetry at radiation doses >5 Gy due to the saturation of the dose response. Different response of the LQ coefficients to the changes of the dose range must be considered during the DRC construction. Proper selection of minimum and maximum dose in calibration experiments makes it possible to improve the goodness of fit of the LQ DRC.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    背景:哮喘治疗指南将吸入性皮质类固醇(ICS)方案分类为低,中等,或高剂量。然而,疗效和安全性没有独立评估。此外,在选择给药方案时,不考虑ICS作用持续时间的差异.我们研究了这些限制对可用ICS分子的功效和安全性影响。
    方法:使用已发布的药效学和药代动力学参数,除了生理学和药理学原理,评估可用ICS分子的疗效和安全性。估计了肺中糖皮质激素受体(GR)占据的程度和持续时间(功效)和皮质醇抑制(全身暴露和安全性)。
    结果:一些ICS方案(例如,糠酸氟替卡松,丙酸氟替卡松,和环索奈德)的疗效较高,但对于全身暴露,与目前如何看待ICS剂量等效相反。疗效和全身暴露的剂量-反应关系的差异对于每个ICS方案是独特的,并反映在它们的治疗指数中。值得注意的是,即使低剂量的大多数ICSs可以在稳定状态的整个剂量间隔内产生高GR占有率(≥90%),这可能解释了先前报道的在临床剂量范围内获得剂量反应的困难,以及观察到大多数临床益处通常发生在低剂量。ICS分子的肺GR占用的估计剂量后持续时间被分类为4-6小时(短),14-16小时(中等),25-40小时(长),或>80小时(超长),提示抗炎作用持续时间可能存在较大差异。
    结论:在现实世界的临床环境中,对处方治疗的依从性可能较差,我们的研究结果表明,在哮喘患者中,长效ICS分子具有显著的治疗优势.
    哮喘患者通常依赖吸入糖皮质激素通过控制肺部炎症来控制症状。吸入皮质类固醇可以在低,中等,或高剂量;然而,的有效性,安全,选择时,不考虑特定吸入皮质类固醇分子的作用持续多长时间。这项研究调查了不同吸入皮质类固醇分子的安全性和有效性。利用已发表的关于抗炎作用模式的数据,以及这些分子从体内吸收和消除的速率,我们估计了它们的有效性和安全性,包括在肺部的作用持续时间和全身暴露水平。一些吸入的皮质类固醇分子,例如糠酸氟替卡松,丙酸氟替卡松,和环索奈德被发现在肺部表现出高度的抗炎效果与最小的全身暴露,对比目前使用的药物分子之间的感知相似性。对于每个吸入的皮质类固醇分子,身体其余部分中不需要的全身作用的抗炎持续时间是独特的。值得注意的是,即使是最低剂量的大多数吸入性皮质类固醇被发现在肺部有效时,支持先前的观察,即临床获益大多在较低剂量下实现。此外,不同吸入性皮质类固醇分子的估计剂量后有效性持续时间在不同分子之间差异很大,有些持续几个小时,有些持续超过80小时,表明他们的作用时间存在显著差异。总的来说,这些发现证明了使用长效吸入性糖皮质激素的潜在优势,特别是对于在坚持处方治疗方案方面可能面临挑战的哮喘患者。
    BACKGROUND: Asthma treatment guidelines classify inhaled corticosteroid (ICS) regimens as low, medium, or high dose. However, efficacy and safety are not independently assessed accordingly. Moreover, differences in ICS duration of action are not considered when a dose regimen is selected. We investigated the efficacy and safety implications of these limitations for available ICS molecules.
    METHODS: Published pharmacodynamic and pharmacokinetic parameters were used, alongside physiological and pharmacological principles, to estimate the efficacy and safety of available ICS molecules. Extent and duration of glucocorticoid receptor (GR) occupancy in the lung (efficacy) and cortisol suppression (systemic exposure and safety) were estimated.
    RESULTS: Some ICS regimens (e.g., fluticasone furoate, fluticasone propionate, and ciclesonide) rank high for efficacy but low for systemic exposure, contrary to how ICS dose equivalence is currently viewed. Differences in dose-response relationships for efficacy and systemic exposure were unique for each ICS regimen and reflected in their therapeutic indices. Notably, even low doses of most ICSs can generate high GR occupancy (≥ 90%) across the entire dose interval at steady state, which may explain previously reported difficulties in obtaining dose responses within the clinical dose range and observations that most clinical benefit typically occurs at low doses. The estimated post dose duration of lung GR occupancy for ICS molecules was categorized as 4-6 h (short), 14-16 h (medium), 25-40 h (long), or > 80 h (ultra-long), suggesting potentially large differences in anti-inflammatory duration of action.
    CONCLUSIONS: In a real-world clinical setting where there may be poor adherence to prescribed therapy, our findings suggest a significant therapeutic advantage for longer-acting ICS molecules in patients with asthma.
    Patients with asthma often rely on inhaled corticosteroids to manage their symptoms by controlling lung inflammation. Inhaled corticosteroids can be used at low, medium, or high doses; however, the effectiveness, safety, and how long the effects last for a particular inhaled corticosteroid molecule are not considered when choosing them. This study investigated the safety and efficacy of different inhaled corticosteroid molecules. Leveraging published data on the mode of anti-inflammatory action and the rates these molecules are absorbed and eliminated from the body, we estimated their effectiveness and safety profiles, including duration of action in the lungs and systemic exposure levels. Some inhaled corticosteroid molecules such as fluticasone furoate, fluticasone propionate, and ciclesonide were found to exhibit high anti-inflammatory effectiveness in the lungs with minimal systemic exposure, contrasting the perceived similarities among currently used drug molecules. Anti-inflammatory duration of the unwanted systemic effect in the rest of the body was unique for each inhaled corticosteroid molecule. Notably, even the lowest doses of most inhaled corticosteroids were found to be effective in the lungs when taken as prescribed, supporting previous observations that clinical benefits are mostly realized at lower doses. Furthermore, estimated post dose durations of effectiveness for different inhaled corticosteroid molecules varied widely among different molecules, with some lasting a few hours and others lasting more than 80 h, suggesting significant differences in their duration of action. Overall, these findings demonstrate the potential advantage of using longer-acting inhaled corticosteroids, particularly for patients with asthma who may face challenges in adhering to prescribed regimens.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

公众号