Understanding the Influence of Nanocarrier-Mediated Brain Delivery on Therapeutic Performance Through Pharmacokinetic-Pharmacodynamic Modeling

This study aimed at evaluating how encapsulation in a regular nanocarrier (NC) (providing extended circulation time) or in a brain-targeting NC (providing prolonged circulation time and increased brain uptake) may influence the therapeutic index compared with the unformulated drug and to explore the key parameters affecting therapeutic performance using a model-based approach. Pharmacokinetic (PK) models were built with chosen PK parameters. For a scenario where central effect depends on area under the unbound brain concentration curve and peripheral toxicity relates to peak unbound plasma concentration, dose-effect and drug-side effect curves were constructed, and the therapeutic index was evaluated. Regular NC improved the therapeutic index compared with the unformulated drug due to reduced peripheral toxicity, while brain-targeting NC enhanced the therapeutic index by lowering peripheral toxicity and increasing central effect. Decreasing drug release rate or systemic clearance of NC with drug still encapsulated could increase the therapeutic index. Also, a drug with shorter half-life would therapeutically benefit more from a NC encapsulation. This work provides insights into how a NC for brain delivery should be optimized to maximize the therapeutic performance and is helpful to predict if and to what extent a drug with certain PK properties would obtain therapeutic benefit from nanoencapsulation.     

Boosting treatment stabilization in patients of amphetamine-type stimulant use disorder

BackgroundTo investigate boosting effects on treatment stabilization in the mandatory treatment modality for patients of amphetamine-type stimulant use disorder.MethodsThis is a retrospective follow-up study over a period from January 2013 to December 2018. We analyzed 425 patients of amphetamine-type stimulant use disorder under mandating treatments. Treatment stabilization for a given patient was defined once 4 negative urinalysis had been observed. We developed a dynamic monitoring model of boosting effects informed by the available data, specifically the number of negative urine samples required to reach stabilization, the sum of urinalyses done at the time when the given number of negative urine samples had been observed and who the patient was. To represent the simulated population, a Monte Carlo method was used to generate p-values from 1000 experiments conducted on a computer.ResultsIn the observed samples, the probability of 4 negative results in urinalysis from 4 outpatient visits was 75.5%. In comparison, the probability for achieving 4th negative results in urinalysis over 4 visits from negative binominal distribution was 57.3%, and from the computer simulation, 49.8%. The observed samples had significantly higher probability of achieving 4 negative results in urinalysis over 4 outpatient visits (p < 0.001).ConclusionsThe mandatory treatment modality boosted treatment stabilization for patients of amphetamine-type stimulant use disorder. The major benefit of using the monitoring model is the ability to monitor boosting effects of stabilization. Results supported the effectiveness of this mandatory treatment modality and can be implemented in deferred-prosecution based treatment modality.     

In Vitro-In Vivo Extrapolation and Hepatic Clearance-Dependent Underprediction

Accurately predicting the hepatic clearance of compounds using in vitro to in vivo extrapolation (IVIVE) is crucial within the pharmaceutical industry. However, several groups have recently highlighted the serious error in the process. Although empirical or regression-based scaling factors may be used to mitigate the common underprediction, they provide unsatisfying solutions because the reasoning behind the underlying error has yet to be determined. One previously noted trend was intrinsic clearance-dependent underprediction, highlighting the limitations of current in vitro systems. When applying these generated in vitro intrinsic clearance values during drug development and making first-in-human dose predictions for new chemical entities though, hepatic clearance is the parameter that must be estimated using a model of hepatic disposition, such as the well-stirred model. Here, we examine error across hepatic clearance ranges and find a similar hepatic clearance-dependent trend, with high clearance compounds not predicted to be so, demonstrating another gap in the field.     

老年轻度认知障碍患者血清瘦素、甲状腺激素水平与局部脑血流量关系的研究

目的 通过检测老年轻度认知障碍（MCI）患者血清瘦素（LEP）、甲状腺激素水平，分析其与局部脑血流量（rCBF）的关系。方法 选择本院收治的128 例老年MCI 患者，另选健康者128 例作为对照组。检测血清LEP、甲状腺激素、大脑各区域rCBF 水平并分析其相关性。结果 老年MCI 组患者左右侧额叶、右侧颞叶、左侧顶叶、左右侧基底节区域脑血流量[（43.81±8.62）mL/（100 g·min）、（43.24±7.93）mL/（100 g·min）、（45.14±6.98）mL/（100 g·min）、（45.86±6.77）mL/（100 g·min）、（67.95±8.52）mL/（100 g·min）、（68.36±8.34）mL/（100 g·min）]低于对照组[（46.39±8.31）mL/（100 g·min）、（46.52±8.56）mL/（100 g·min）、（47.37±7.04）mL/（100 g·min）、（48.25±6.98）mL/（100 g·min）、（70.34±8.96）mL/（100 g·min）、（70.58±8.57）mL/（100 g·min）]（P＜0.05）。老年MCI 组患者血清LEP、T3、FT3 水平[（4.87±1.56）μg/L、（1.21±0.16）nmol/L、（3.04±0.36）pmol/L]低于对照组[（11.45±3.92）μg/L、（1.68±0.21）nmol/L、（4.82±1.21）pmol/L]（P＜0.05），TSH 水平为（2.78±0.75）IU/mL，高于对照组的（1.13±0.38）IU/mL（P＜0.05）。老年MCI 患者血清LEP 水平与左侧额叶、右侧颞叶、左侧顶叶rCBF 呈正相关（r=0.452、0.537、0.544，P 均＜0.05），T3 水平与左侧额叶、右侧颞叶rCBF 呈正相关（r=0.427、0.521，P 均＜0.05），FT3 水平与右侧颞叶rCBF 呈正相关（r=0.492，P＜0.05），TSH 水平与左侧额叶、右侧颞叶rCBF 呈负相关（r=-0.463、-0.489，P 均＜0.05）。结论 老年MCI 患者血清中LEP、T3、FT3 水平降低，TSH 水平升高，且与不同区域rCBF 有相关性，可通过调控脑血管功能影响rCBF 变化水平。     

椎弓根螺钉三椎体内固定对脊椎爆裂性骨折患者椎体与神经功能状态的影响观察

目的:探讨椎弓根螺钉三椎体内固定对脊椎爆裂性骨折患者椎体与神经功能状态的影响.方法:选取2013年7月至2015年1月于本院进行治疗的58例脊椎爆裂性骨折患者为研究对象,对其进行回顾性研究,将其根据手术方式不同分为对照组(短节段椎弓根内固定组)29例和观察组(椎弓根螺钉三椎体内固定组)29例,然后将两组患者手术前与手术后不同时间的伤椎恢复指标与血清神经功能相关指标进行比较.结果:观察组手术后不同时间的伤椎恢复指标中的后凸Cobb角、椎体平移率、椎体高度丢失率与血清神经功能相关指标中的BDNF、NSE、NGF及S100B均显著好于同期的对照组指标,并且明显好于其治疗前,均有显著性差异(P＜0.05).结论:椎弓根螺钉三椎体内固定可更为有效地恢复脊椎爆裂性骨折患者椎体参数,并且更有助于神经功能状态的恢复.     

40岁以上高龄女性体外受精-胚胎移植妊娠结局分析

目的：探讨40岁以上高龄女性体外受精-胚胎移植（IVF-ET）的妊娠结局，旨在为高龄女性提供生育咨询以及为改善高龄女性个体化辅助生殖治疗结局提供临床依据。方法：选择我院生殖中心2015年1月—2017年12月女方年龄≥40岁且使用自身卵子行体外受精的共2 467个治疗周期资料，对各项临床数据进行回顾性分析。结果：40岁及以上行辅助生殖治疗的患者，随着女性年龄增加获卵数明显减少（40～48岁女性平均获卵数分别为2.97、 2.69、2.17、2.01、1.77、1.61、1.68、1.29和1.00，44～48岁与40～43岁依次组间比较均P＜0.05），尤其是44岁以上女性胚胎发育潜能明显降低（40～48岁囊胚形成率分别为48.90%、43.72%、33.67%、34.29%、24.39%、21.14%、26.32%、16.67%和0%，44～48岁与40～43岁组间依次比较均P＜0.05）。共有518个周期行新鲜胚胎移植，结果显示，随女性年龄增加，临床妊娠率（40～48岁临床妊娠率分别为26.92%、21.15%、20.79%、10.96%、18.87%、11.11%、5.88%、0%和0%，43～48岁与40～42岁组间依次比较均P＜0.05）、种植率（40～48岁种植率分别为23.65%、19.51%、17.70%、8.54%、7.49%、10.81%、5.56%、0%和0%，43～48岁与40～42岁组间依次比较均P＜0.05）和活产率均显著降低（40～46岁活产率分别为18.46%、10.58%、9.90%、5.48%、5.66%、2.78%和5.88%，43～46岁与40～42岁组间依次比较均P＜0.05），43岁以上者结局更差。44岁以上女性自然流产率明显增高（40～45岁流产率分别为31.43%、50.00%、52.38%、50.00%、70.00%和75.00%，44～45岁与40～43岁组间依次比较均P＜0.05）。46岁女性仅1例妊娠并分娩，47岁和48岁女性均无成功妊娠。与抗苗勒管激素（AMH）＞1.0 ng/mL组相比，AMH≤1.0 ng/mL组妊娠率、种植率及活产率均显著下降（27.04% vs. 14.74%，22.99% vs. 13.50%，15.88% vs. 7.37%；均P＜0.05），流产率明显升高（41.27% vs. 50.00%，P＜0.05）。结论：≥40岁高龄女性随年龄增长生育力逐渐降低。40～43岁年龄段女性助孕仍有一定的价值，尤其是卵巢仍有一定储备者（AMH＞1.0 ng/mL），但44岁以上女性原则上不再建议ART助孕，对于46岁以上卵巢功能衰竭的女性强烈建议卵子捐赠或收养。     

Local Landscapes of Breastfeeding: A comparison of breastfeeding amongst mothers in low- and high-income neighborhoods in Bristol,UK

This paper compares experiences of breastfeeding outside the home for women living in low-income and high-income neighborhoods of the same city. Our findings are based on an analysis of 22 interviews with breastfeeding mothers (11 in each of two study areas) undertaken in Bristol, UK in 2017. We extend existing scholarship by showing how experiences of breastfeeding vary not only at the regional level but between local areas of the same city, and outline how our findings can inform policy. We advance literature on maternal bodies by exploring how local “landscapes” of breastfeeding emerge as mothers encounter and negotiate different socio-material landscapes and locally-differentiated norms about “appropriate” maternal embodiment. We argue that these variegated interactions can lead to different orientations to space and forms of spatial practice on the part of breastfeeding mothers, as well as different kinds of maternal identities.