Ionophore and Biometal Modulation of P-glycoprotein Expression and Function in Human Brain Microvascular Endothelial Cells

Purpose

Biometals such as zinc and copper have been shown to affect tight junction expression and subsequently blood-brain barrier (BBB) integrity. Whether these biometals also influence the expression and function of BBB transporters such as P-glycoprotein (P-gp) however is currently unknown.

Methods

Using the immortalised human cerebral microvascular endothelial (hCMEC/D3) cell line, an in-cell western assay (alongside western blotting) assessed relative P-gp expression after treatment with the metal ionophore clioquinol and biometals zinc and copper. The fluorescent P-gp substrate rhodamine-123 was employed to observe functional modulation, and inductively coupled plasma mass spectrometry (ICP-MS) provided information on biometal trafficking.

Results

A 24-h treatment with clioquinol, zinc and copper (0.5, 0.5 and 0.1 μM) induced a significant upregulation of P-gp (1.7-fold) assessed by in-cell western and this was confirmed with western blotting (1.8-fold increase). This same treatment resulted in a 23% decrease in rhodamine-123 accumulation over a 1 h incubation. ICP-MS demonstrated that while t8his combination treatment had no effect on intracellular zinc concentrations, the treatment significantly enhanced bioavailable copper (4.6-fold).

Conclusions

Enhanced delivery of copper to human brain microvascular endothelial cells is associated with enhanced expression and function of the important efflux pump P-gp, which may provide therapeutic opportunities for P-gp modulation.

     

A new risk prediction model for critical care: the Intensive Care National Audit & Research Centre (ICNARC) model

OBJECTIVE: To develop a new model to improve risk prediction for admissions to adult critical care units in the UK. DESIGN: Prospective cohort study. SETTING: The setting was 163 adult, general critical care units in England, Wales, and Northern Ireland, December 1995 to August 2003. PATIENTS: Patients were 216,626 critical care admissions. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The performance of different approaches to modeling physiologic measurements was evaluated, and the best methods were selected to produce a new physiology score. This physiology score was combined with other information relating to the critical care admission-age, diagnostic category, source of admission, and cardiopulmonary resuscitation before admission-to develop a risk prediction model. Modeling interactions between diagnostic category and physiology score enabled the inclusion of groups of admissions that are frequently excluded from risk prediction models. The new model showed good discrimination (mean c index 0.870) and fit (mean Shapiro's R 0.665, mean Brier's score 0.132) in 200 repeated validation samples and performed well when compared with recalibrated versions of existing published risk prediction models in the cohort of patients eligible for all models. The hypothesis of perfect fit was rejected for all models, including the Intensive Care National Audit & Research Centre (ICNARC) model, as is to be expected in such a large cohort. CONCLUSIONS: The ICNARC model demonstrated better discrimination and overall fit than existing risk prediction models, even following recalibration of these models. We recommend it be used to replace previously published models for risk adjustment in the UK.     

藻黄胶囊Ⅱ号延缓慢性肾功能衰竭进展的实验研究

目的 囊Ⅱ号液对人肾小球系膜细胞(GMC)、增殖及分泌纤维连接蛋白(FN)、转化生长因子β1(TGF-β1)的影响.方法 体外人GMC培养,细胞成熟后进行药物孵育,观察细胞增殖情况,检测藻黄胶囊Ⅱ号液对人GMC分泌的FN、TGF-β1的影响.结果 实验研究显示藻黄胶囊Ⅱ号液可明显抑制人GMC的增殖,明显抑制人GMC分泌FN、TGF-β1.结论 藻黄胶囊Ⅱ号液可抑制人GMC的增殖及FN、TGF-β1分泌,提示其可减少肾小球和肾间质细胞外基质的堆积.     

Anxiety Sensitivity Prospectively Predicts Increased Acute Posttraumatic Stress and Related Symptoms After Sexual Assault

Anxiety sensitivity is a potential risk factor for posttraumatic stress symptoms (PTSS) and has been hypothesized to contribute to PTSS development. However, few prospective studies have evaluated whether anxiety sensitivity predicts PTSS. In a subsample of 48 women sexual assault survivors enrolled as part of a larger prospective observational study, elevated anxiety sensitivity measured via a brief assessment 1 week after experiencing a sexual assault was concurrently associated with PTSS at 1 week and prospectively predicted PTSS 6 weeks after the event, with small-to-medium effect sizes, η²_p = .10, even after covarying for trauma history. Heightened anxiety sensitivity at 1-week postevent also interacted with time to predict anxiety and depression both before and after sexual assault, with medium-to-large effect sizes, η_p² = .21– .24. This is consistent with research linking anxiety sensitivity to PTSS, but this was the first prospective study of which we are aware to demonstrate that anxiety sensitivity in the acute posttrauma period predicts PTSS among women who have recently experienced sexual assault. Future research should use the full Anxiety Sensitivity Index to replicate findings in a larger sample and explore whether targeting anxiety sensitivity could mitigate the development of PTSS in this vulnerable population.     

A pilot randomised controlled trial of the management of systolic blood pressure during endovascular thrombectomy for acute ischaemic stroke

It is unknown whether systolic blood pressure augmentation during endovascular thrombectomy improves clinical outcomes. This pilot randomised controlled trial aimed to assess the feasibility of differential systolic blood pressure targeting during endovascular thrombectomy procedures for anterior circulation ischaemic stroke. Fifty-one eligible patients fulfilling the national criteria for endovascular thrombectomy were randomly assigned to receive either standard or augmented systolic blood pressure management from the start of anaesthesia to recanalisation of the target vessel. Systolic blood pressure targets for the standard and augmented groups were 130–150 mmHg and 160–180 mmHg, respectively. The study achieved all feasibility targets, including a recruitment rate of 3.5 participants per week and median (IQR [range]) of mean systolic blood pressure separation between groups of 139 (135–143 [115–154]) vs. 167 (150–175 [113–188]) mmHg, p < 0.001. Data completeness was 99%. Independent functional recovery at 90 days (modified Rankin Scale 0, 1 or 2) was achieved in 30 (59%) patients, which is consistent with previously published data. There were no safety concerns with trial procedures. In conclusion, a large randomised controlled efficacy trial of standard vs. augmented systolic blood pressure management during endovascular thrombectomy is feasible.     

Fluorescence in situ hybridization mapping of translocations and deletions involving the short arm of human chromosome 12 in malignant hematologic diseases

Translocations and deletions of the short arm of chromosome 12 [t(12p) and del(12p)] are common recurring abnormalities in a broad spectrum of hematologic malignant diseases. We studied 20 patients and one cell line whose cells contained 12p13 translocations and/or 12p deletions using fluorescence in situ hybridization (FISH) with phage, plasmid, and cosmid probes that we previously mapped and ordered on 12p12-13. FISH analysis showed that the 12p13 translocation breakpoints were clustered between two cosmids, D12S133 and D12S142, in 11 of 12 patients and in one cell line. FISH analysis of 11 patients with deletions demonstrated that the deletions were interstitial rather than terminal and that the distal part of 12p12, including the GDI-D4 gene and D12S54 marker, was deleted in all 11 patients. Moreover, FISH analysis showed that cells from 3 of these patients contained both a del(12p) and a 12p13 translocation and that the affected regions of these rearrangements appeared to overlap. We identified three yeast artificial chromosome (YAC) clones that span all the 12p13 translocation breakpoints mapped between D12S133 and D12S142. They have inserts of human DNA between 1.39 and 1.67 Mb. Because the region between D12S133 and D12S142 also represents the telomeric border of the smallest commonly deleted region of 12p, we also studied patients with a del(12p) using these YACs. The smallest YAC, 964c10, was deleted in 8 of 9 patients studied. In the other patient, the YAC labeled the del(12p) chromosome more weakly than the normal chromosome 12, suggesting that a part of the YAC was deleted. Thus, most 12p13 translocation breakpoints were clustered within the sequences contained in the 1.39 Mb YAC and this YAC appears to include the telomeric border of the smallest commonly deleted region. Whether the same gene is involved in both the translocations and deletions is presently unknown.