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Central Nervous System Distributional Kinetics of Selected Histone Deacetylase Inhibitors. J Pharmacol Exp Ther 2024:JPET-AR-2024-002170. [PMID: 38670802 DOI: 10.1124/jpet.124.002170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2024] [Revised: 04/02/2024] [Accepted: 04/15/2024] [Indexed: 04/28/2024] Open
Abstract
Histone deacetylase expression and activity are often dysregulated in central nervous system (CNS) tumors, providing a rationale for investigating histone deacetylase inhibitors (HDACIs) in selected brain tumor patients. Although many HDACIs have shown potential in in vitro studies, they have had modest efficacy in vivo This lack of activity could be due to insufficient CNS exposure to the unbound drug. In this study, we investigated the systemic pharmacokinetics and subsequent CNS distribution of two potent HDACIs, vorinostat and quisinostat, in the murine model. Both compounds undergo in vitro degradation in mouse plasma, requiring precautions during sample processing. They also have short half-lives in vivo, in both plasma and CNS, which may lead to diminished efficacy. Transgenic transporter-deficient mouse models show that the CNS delivery of vorinostat was not limited by the two major blood-brain barrier efflux transporters, p-glycoprotein and breast-cancer-resistance protein. Vorinostat had an unbound CNS tissue-to-plasma partition coefficient of 0.06 {plus minus} 0.02. Conversely, the exposure of unbound quisinostat in the brain was only 0.02 {plus minus} 0.001 of that in the plasma, and the CNS distribution of quisinostat was limited by the activity of p-glycoprotein. To gain further context for these findings, the CNS distributional kinetics for vorinostat and quisinostat were compared to another hydroxamic acid HDACI, panobinostat. A comprehensive understanding of the CNS target exposure to unbound HDACI, along with known potencies from in vitro testing, can inform the prediction of a therapeutic window for HDACIs that have limited CNS exposure to unbound drug and guide targeted dosing strategies. Significance Statement This study indicates that quisinostat and vorinostat are susceptible to enzymatic degradation in the plasma, and to a lesser degree, in the target CNS tissues. Employing techniques that minimize the post-sampling degradation in plasma, brain and spinal cord, accurate CNS distributional kinetic parameters for these potentially useful compounds were determined. A knowledge of CNS exposure (Kp,uu), time to peak, and duration can inform dosing strategies in preclinical and clinical trials in selected CNS tumors.
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Pharmacokinetics of panobinostat: Inter-species difference in metabolic stability. J Pharmacol Exp Ther 2024; 389:JPET-AR-2023-002051. [PMID: 38409112 PMCID: PMC10949161 DOI: 10.1124/jpet.123.002051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Revised: 01/13/2024] [Accepted: 01/30/2024] [Indexed: 02/28/2024] Open
Abstract
Panobinostat is a potent pan-HDAC inhibitor that has been tested in multiple studies for the treatment of brain tumors. There have been contrasting views surrounding its efficacy for the treatment of tumors in the CNS following systemic administration when examined in different models or species. We conducted experiments using three different mouse strains or genotypes to have a more comprehensive understanding of the systemic as well as the CNS distributional kinetics of panobinostat. Our study found that panobinostat experienced rapid degradation in vitro in FVB mouse matrices and a faster degradation rate was observed at 37{degree sign}C compared with room temperature and 4{degree sign}C, suggesting that the in vitro instability of panobinostat was due to enzymatic metabolism. Panobinostat also showed inter-strain and inter-species differences in the in vitro plasma stability; and was stable in human plasma. The objective of this study was to examine the in vitro metabolic stability of panobinostat in different matrices and assess the influence of that metabolic stability on the in vivo pharmacokinetics and CNS delivery of panobinostat. Importantly, the plasma stability in various mouse strains was not reflected in the in vivo systemic pharmacokinetic behavior of panobinostat. Several hypotheses arise from this finding, including: the binding of panobinostat to red blood cells, the existence of competing endogenous compounds to enzyme(s), the distribution into tissues with a lower level of enzymatic activity or the metabolism occurring in the plasma is a small fraction of the total metabolism in vivo Significance Statement Panobinostat showed different in vitro degradation in plasma from different mouse strains and genotypes. However, despite the differences surrounding in vitro plasma stability, panobinostat showed similar in vivo pharmacokinetic behavior in different mouse models. This suggests that the inter-strain difference in enzymatic activity did not affect the in vivo pharmacokinetic behavior of panobinostat and its CNS distribution in mice. This lack of translation between in vitro metabolism assays and in vivo disposition can confound drug development.
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Delivery versus Potency in Treating Brain Tumors: BI-907828, a MDM2-p53 Antagonist with Limited BBB Penetration but Significant In Vivo Efficacy in Glioblastoma. Mol Cancer Ther 2024; 23:47-55. [PMID: 37828724 PMCID: PMC10843165 DOI: 10.1158/1535-7163.mct-23-0217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Revised: 08/03/2023] [Accepted: 10/10/2023] [Indexed: 10/14/2023]
Abstract
MDM2-p53 inhibition may be effective in glioblastoma (GBM). This study evaluates the pharmacokinetics/pharmacodynamics of BI-907828, a potent antagonist of MDM2, in GBM, and demonstrates a translational paradigm with a focus on a unified "Delivery - Potency - Efficacy" relationship in drug development for central nervous system(CNS) tumors. BI-907828 was tested for cytotoxicity and MDM2-p53 pathway inhibition. Systemic pharmacokinetics and transport mechanisms controlling CNS distribution were evaluated in mice. BI-907828 free fractions in cell media, mouse and human specimens were measured to determine "active" unbound concentrations. Efficacy measures, including overall survival and target expression were assessed in mouse orthotopic GBM xenografts. BI-907828 exhibited potent inhibition of MDM2-p53 pathway and promoted cell death in GBM TP53 wild-type cells. MDM2-amplified cells are highly sensitive to BI-907828, with an effective unbound concentration of 0.1 nmol/L. The CNS distribution of BI-907828 is limited by blood-brain barrier (BBB) efflux mediated by P-gp, resulting in a Kp,uu_brain of 0.002. Despite this seemingly "poor" BBB penetration, weekly administration of 10 mg/kg BI-907828 extended median survival of orthotopic GBM108 xenografts from 28 to 218 days (P < 0.0001). This excellent efficacy can be attributed to high potency, resulting in a limited, yet effective, exposure in the CNS. These studies show that efficacy of BI-907828 in orthotopic models is related to high potency even though its CNS distribution is limited by BBB efflux. Therefore, a comprehensive understanding of all aspects of the "Delivery - Potency - Efficacy" relationship is warranted in drug discovery and development, especially for treatment of CNS tumors.
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Central Nervous System Distribution of Panobinostat in Preclinical Models to Guide Dosing for Pediatric Brain Tumors. J Pharmacol Exp Ther 2023; 387:315-327. [PMID: 37827699 PMCID: PMC10658912 DOI: 10.1124/jpet.123.001826] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Revised: 09/24/2023] [Accepted: 09/28/2023] [Indexed: 10/14/2023] Open
Abstract
Achieving adequate exposure of the free therapeutic agent at the target is a critical determinant of efficacious chemotherapy. With this in mind, a major challenge in developing therapies for central nervous system (CNS) tumors is to overcome barriers to delivery, including the blood-brain barrier (BBB). Panobinostat is a nonselective pan-histone deacetylase inhibitor that is being tested in preclinical and clinical studies, including for the treatment of pediatric medulloblastoma, which has a propensity for leptomeningeal spread and diffuse midline glioma, which can infiltrate into supratentorial brain regions. In this study, we examined the rate, extent, and spatial heterogeneity of panobinostat CNS distribution in mice. Transporter-deficient mouse studies show that panobinostat is a dual substrate of P-glycoprotein (P-gp) and breast cancer resistant protein (Bcrp), which are major efflux transporters expressed at the BBB. The CNS delivery of panobinostat was moderately limited by P-gp and Bcrp, and the unbound tissue-to-plasma partition coefficient of panobinostat was 0.32 and 0.21 in the brain and spinal cord in wild-type mice. In addition, following intravenous administration, panobinostat demonstrated heterogeneous distribution among brain regions, indicating that its efficacy would be influenced by tumor location or the presence and extent of leptomeningeal spread. Simulation using a compartmental BBB model suggests inadequate exposure of free panobinostat in the brain following a recommended oral dosing regimen in patients. Therefore, alternative approaches to CNS delivery may be necessary to have adequate exposure of free panobinostat for the treatment of a broad range of pediatric brain tumors. SIGNIFICANCE STATEMENT: This study shows that the central nervous system (CNS) penetration of panobinostat is limited by P-gp and Bcrp, and its efficacy may be limited by inadequate distribution to the tumor. Panobinostat has heterogeneous distribution into various brain regions, indicating that its efficacy might depend on the anatomical location of the tumors. These distributional parameters in the mouse CNS can inform both preclinical and clinical trial study design and may guide treatment for these devastating brain tumors in children.
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How Much is Enough? Impact of Efflux Transporters on Drug delivery Leading to Efficacy in the Treatment of Brain Tumors. Pharm Res 2023; 40:2731-2746. [PMID: 37589827 PMCID: PMC10841221 DOI: 10.1007/s11095-023-03574-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Accepted: 07/19/2023] [Indexed: 08/18/2023]
Abstract
The lack of effective chemotherapeutic agents for the treatment of brain tumors is a serious unmet medical need. This can be attributed, in part, to inadequate delivery through the blood-brain barrier (BBB) and the tumor-cell barrier, both of which have active efflux transporters that can restrict the transport of many potentially effective agents for both primary and metastatic brain tumors. This review briefly summarizes the components and function of the normal BBB with respect to drug penetration into the brain and the alterations in the BBB due to brain tumor that could influence drug delivery. Depending on what is rate-limiting a compound's distribution, the limited permeability across the BBB and the subsequent delivery into the tumor cell can be greatly influenced by efflux transporters and these are discussed in some detail. Given these complexities, it is necessary to quantify the extent of brain distribution of the active (unbound) drug to compare across compounds and to inform potential for use against brain tumors. In this regard, the metric, Kp,uu, a brain-to-plasma unbound partition coefficient, is examined and its current use is discussed. However, the extent of active drug delivery is not the only determinant of effective therapy. In addition to Kp,uu, drug potency is an important parameter that should be considered alongside drug delivery in drug discovery and development processes. In other words, to answer the question - How much is enough? - one must consider how much can be delivered with how much needs to be delivered.
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Blood-brain barrier disruption defines the extracellular metabolome of live human high-grade gliomas. Commun Biol 2023; 6:653. [PMID: 37340056 PMCID: PMC10281947 DOI: 10.1038/s42003-023-05035-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Accepted: 06/12/2023] [Indexed: 06/22/2023] Open
Abstract
The extracellular microenvironment modulates glioma behaviour. It remains unknown if blood-brain barrier disruption merely reflects or functionally supports glioma aggressiveness. We utilised intra-operative microdialysis to sample the extracellular metabolome of radiographically diverse regions of gliomas and evaluated the global extracellular metabolome via ultra-performance liquid chromatography tandem mass spectrometry. Among 162 named metabolites, guanidinoacetate (GAA) was 126.32x higher in enhancing tumour than in adjacent brain. 48 additional metabolites were 2.05-10.18x more abundant in enhancing tumour than brain. With exception of GAA, and 2-hydroxyglutarate in IDH-mutant gliomas, differences between non-enhancing tumour and brain microdialysate were modest and less consistent. The enhancing, but not the non-enhancing glioma metabolome, was significantly enriched for plasma-associated metabolites largely comprising amino acids and carnitines. Our findings suggest that metabolite diffusion through a disrupted blood-brain barrier may largely define the enhancing extracellular glioma metabolome. Future studies will determine how the altered extracellular metabolome impacts glioma behaviour.
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Sex difference in neurological outcome and post-cardiac arrest care in out-of-hospital cardiac arrest patients treated with targeted temperature management. Eur Heart J 2023. [DOI: 10.1093/eurheartj/ehac779.063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Abstract
Funding Acknowledgements
Type of funding sources: None.
Objectives
Conflicting results regarding sex-based differences in the outcomes of out-of-hospital cardiac arrest (OHCA) patients have been reported. Furthermore, no study has examined whether differences in in-hospital interventions and courses are driven by sex differences. This study evaluated the effect of sex on the in-hospital course of these patients as well as the survival rates and long-term neurological outcomes of comatose OHCA patients treated with targeted temperature management (TTM).
Methods
We retrospectively analyzed the Korean Hypothermia Network prospective registry composed of data collected from 22 hospitals in Korea between October 2015 and December 2018. To evaluate the effect of sex on patient outcomes, we created various multivariate logistic regression models including baseline characteristics, resuscitation, and in-hospital care variables with an interaction term (age × sex). We also performed a stratified analysis of different age groups (less than 50 years of age and older). Regarding the difference in in-hospital courses, we compared daily total and SOFA sub-scores between the sexes and analyzed whether the decision regarding early cardiac interventions and limitations in in-hospital care were associated with sex.
Results
Among 1339 patients included in the study, 952 were men and 387 were women. There were no differences in age or modified comorbidity index values between the gender groups. Women were more likely to experience cardiac arrest at home and unwitnessed arrests, whereas men were more likely to have shockable initial rhythm, cardiac cause arrest, and ST-segment elevation myocardial infarction (STEMI) on initial electrocardiography and undergo early coronary interventions. The rate of survival to discharge was similar, but men showed better 6-month neurological outcomes. After adjusting for confounders, the male sex was not associated with survival to discharge or good 6-month neurological outcomes. There was no association between sex and outcome in patients of reproductive age and no interaction between age and sex. Regarding the in-hospital course, the daily total and SOFA sub-scores were similar in both sexes. The adjusted effect of sex was not associated with the clinician’s decision to perform early cardiac interventions. The decision to discontinue life-sustaining treatment was determined by poor prognostic factors, not by sex.
Conclusions
The findings suggested that men had more favorable 6-month survivals and good neurological outcomes compared to women since they had more favorable resuscitation variables. However, after adjusting for confounders, there was no difference between the sexes. This result was consistent with the data in patients of reproductive age. The results regarding in-hospital course showed that daily patient severity scores, early cardiac interventions, resource consumption, and the rates of withdrawal/withholding of in-hospital care were similar in men and women.
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Overcoming translational barriers in H3K27-altered diffuse midline glioma: Increasing the drug-tumor residence time. Neurooncol Adv 2023; 5:vdad033. [PMID: 37128506 PMCID: PMC10148679 DOI: 10.1093/noajnl/vdad033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/29/2023] Open
Abstract
Background H3K27-altered diffuse midline glioma (DMG) is the deadliest pediatric brain tumor; despite intensive research efforts, every clinical trial to date has failed. Is this because we are choosing the wrong drugs? Or are drug delivery and other pharmacokinetic variables at play? We hypothesize that the answer is likely a combination, where optimization may result in a much needed novel therapeutic approach. Methods We used in vitro drug screening, patient samples, and shRNA knockdown models to identify an upregulated target in DMG. A single small molecule protein kinase inhibitor with translational potential was selected for systemic and direct, loco-regional delivery to patient-derived xenografts (PDX) and genetically engineered mouse models (GEMM). Pharmacokinetic studies were conducted in non-tumor bearing rats. Results Aurora kinase (AK) inhibitors demonstrated strong antitumor effects in DMG drug screens. Additional in vitro studies corroborated the importance of AK to DMG survival. Systemic delivery of alisertib showed promise in subcutaneous PDX but not intracranial GEMM and PDX models. Repeated loco-regional drug administration into the tumor through convection-enhanced delivery (CED) was equally inefficacious, and pharmacokinetic studies revealed rapid clearance of alisertib from the brain. In an effort to increase the drug to tumor residence time, continuous CED over 7 days improved drug retention in the rodent brainstem and significantly extended survival in both orthotopic PDXs and GEMMs. Conclusions These studies provide evidence for increasing drug-tumor residence time of promising targeted therapies via extended CED as a valuable treatment strategy for DMG.
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WSD-0922, a novel brain-penetrant inhibitor of epidermal growth factor receptor, promotes survival in glioblastoma mouse models. Neurooncol Adv 2023; 5:vdad066. [PMID: 37324218 PMCID: PMC10263119 DOI: 10.1093/noajnl/vdad066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/17/2023] Open
Abstract
Background Although the epidermal growth factor receptor (EGFR) is a frequent oncogenic driver in glioblastoma (GBM), efforts to therapeutically target this protein have been largely unsuccessful. The present preclinical study evaluated the novel EGFR inhibitor WSD-0922. Methods We employed flank and orthotopic patient-derived xenograft models to characterize WSD-0922 and compare its efficacy to erlotinib, a potent EGFR inhibitor that failed to provide benefit for GBM patients. We performed long-term survival studies and collected short-term tumor, plasma, and whole-brain samples from mice treated with each drug. We utilized mass spectrometry to measure drug concentrations and spatial distribution and to assess the impact of each drug on receptor activity and cellular signaling networks. Results WSD-0922 inhibited EGFR signaling as effectively as erlotinib in in vitro and in vivo models. While WSD-0922 was more CNS penetrant than erlotinib in terms of total concentration, comparable concentrations of both drugs were measured at the tumor site in orthotopic models, and the concentration of free WSD-0922 in the brain was significantly less than the concentration of free erlotinib. WSD-0922 treatment provided a clear survival advantage compared to erlotinib in the GBM39 model, with marked suppression of tumor growth and most mice surviving until the end of the study. WSD-0922 treatment preferentially inhibited phosphorylation of several proteins, including those associated with EGFR inhibitor resistance and cell metabolism. Conclusions WSD-0922 is a highly potent inhibitor of EGFR in GBM, and warrants further evaluation in clinical studies.
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DDEL-05. PHARMACOKINETICS AND CNS DISTRIBUTION OF A NOVEL ATM INHIBITOR, WSD0628, FOR THE TREATMENT OF BRAIN TUMORS. Neuro Oncol 2022. [DOI: 10.1093/neuonc/noac209.351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Abstract
The treatment of brain tumors using chemo- and radio-sensitizers may be limited by a lack of effective drug delivery. Radiation and some cytotoxic therapies induce DNA damage, and DNA damage response (DDR) pathways modulate resistance to effective chemo-radiation therapy. Inhibiting DDR pathways by targeting ATM leads to sensitization and enhances cytotoxicity. The purpose of this study is to determine the key pre-clinical pharmacokinetic parameters and mechanisms that influence the CNS delivery of WSD0628, a novel ATM inhibitor. Pharmacokinetics and CNS distribution studies were conducted in FVB wild-type mice following intravenous (IV) and oral (PO) dosing (5 mg/kg). Plasma, brain, and spinal cord samples were harvested after dosing and drug concentrations were measured using LC-MS/MS. The free fraction of WSD0628 was measured in plasma, brain, and spinal cord using rapid equilibrium dialysis. Our results indicate that WSD0628 has a half-life of 4.11 hrs and a high oral bioavailability (0.95). The brain partition coefficient (AUCbrain/AUCplasma, i.e., Kp, brain) is 0.05 and 0.11 after IV and PO dosing, respectively. The free fraction in plasma is 2.01 ± 0.02 % and in brain it is 1.22 ± 0.40 %. The unbound brain partition coefficient (Kpuu brain) is 0.03 and 0.06 after IV and PO dosing, respectively. The differential binding to plasma and brain tissues results in a relatively low Kpuu, a key parameter describing brain penetrability. These data show that WSD0628, a highly potent inhibitor of ATM, reached sufficient concentrations in brain after a single dose of 5 mg/kg to engage ATM over the desired time frame and elicit a response after DNA damage by chemo-radiotherapy. WSD0628 shows promising potential and further evaluations are underway to determine if efflux transporters at the BBB limit its brain distribution.
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Murine Central Nervous System and Bone Marrow Distribution of the Aurora A Kinase Inhibitor Alisertib: Pharmacokinetics and Exposure at the Sites of Efficacy and Toxicity. J Pharmacol Exp Ther 2022; 383:44-55. [PMID: 36279392 PMCID: PMC9513880 DOI: 10.1124/jpet.122.001268] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Accepted: 08/01/2022] [Indexed: 11/22/2022] Open
Abstract
Important challenges in developing drugs that target central nervous system (CNS) tumors include overcoming barriers for CNS delivery and reducing systemic side effects. Alisertib, an aurora A kinase inhibitor, has been examined for treatment of several CNS tumors in preclinical and clinical studies. In this study, we investigated the distribution of alisertib into the CNS, the site of efficacy for brain tumors, and into the bone marrow, the site of dose-limiting toxicity leading to myelosuppression. Mechanisms influencing site-specific distribution, such as active transport mediated by the efflux proteins, p-glycoprotein (P-gp) and breast cancer resistance protein (Bcrp), were examined. Alisertib exposure to the brain in wild-type mice was less than 1% of that in the plasma, and was evenly distributed throughout various brain regions and the spinal cord. Studies using transporter knockout mice and pharmacological inhibition show that alisertib CNS distribution is influenced by P-gp, but not Bcrp. Conversely, upon systemic administration, alisertib distribution to the bone marrow occurred rapidly, was not significantly limited by efflux transporters, and reached higher concentrations than in the CNS. This study demonstrates that, given an equivalent distributional driving force exposure in plasma, the exposure of alisertib in the brain is significantly less than that in the bone marrow, suggesting that targeted delivery may be necessary to guarantee therapeutic efficacy with minimal risk for adverse events.Therefore, these data suggest that, to improve the therapeutic index when using alisertib for brain tumors, a localized regional delivery, such as convection-enhanced delivery, may be warranted. SIGNIFICANCE STATEMENT: The CNS penetration of alisertib is limited with uniform distribution in various regions of the brain, and P-gp efflux is an important mechanism limiting that CNS distribution. Alisertib rapidly distributes into the bone marrow, a site of toxicity, with a greater exposure than in the CNS, a possible site of efficacy. These results suggest a need to design localized delivery strategies to improve the CNS exposure of alisertib and limit systemic toxicities in the treatment of brain tumors.
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Abstract
Brain tumours have a poor prognosis and lack effective treatments. The blood-brain barrier (BBB) represents a major hurdle to drug delivery to brain tumours. In some locations in the tumour, the BBB may be disrupted to form the blood-brain tumour barrier (BBTB). This leaky BBTB enables diagnosis of brain tumours by contrast enhanced magnetic resonance imaging; however, this disruption is heterogeneous throughout the tumour. Thus, relying on the disrupted BBTB for achieving effective drug concentrations in brain tumours has met with little clinical success. Because of this, it would be beneficial to design drugs and drug delivery strategies to overcome the 'normal' BBB to effectively treat the brain tumours. In this review, we discuss the role of BBB/BBTB in brain tumour diagnosis and treatment highlighting the heterogeneity of the BBTB. We also discuss various strategies to improve drug delivery across the BBB/BBTB to treat both primary and metastatic brain tumours. Recognizing that the BBB represents a critical determinant of drug efficacy in central nervous system tumours will allow a more rapid translation from basic science to clinical application. A more complete understanding of the factors, such as BBB-limited drug delivery, that have hindered progress in treating both primary and metastatic brain tumours, is necessary to develop more effective therapies.
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Central Nervous System Delivery of the Catalytic Subunit of DNA-Dependent Protein Kinase Inhibitor Peposertib as Radiosensitizer for Brain Metastases. J Pharmacol Exp Ther 2022; 381:217-228. [PMID: 35370138 PMCID: PMC9190234 DOI: 10.1124/jpet.121.001069] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Accepted: 03/21/2022] [Indexed: 07/22/2023] Open
Abstract
Cytotoxic effects of chemotherapy and radiation therapy (RT) used for the treatment of brain metastases results from DNA damage within cancer cells. Cells rely on highly evolved DNA damage response (DDR) pathways to repair the damage caused by these treatments. Inhibiting these repair pathways can further sensitize cancer cells to chemotherapy and RT. The catalytic subunit of DNA-dependent protein kinase, in a complex with Ku80 and Ku70, is a pivotal regulator of the DDR, and peposertib is a potent inhibitor of this catalytic subunit. The characterization of central nervous system (CNS) distributional kinetics of peposertib is critical in establishing a therapeutic index in the setting of brain metastases. Our studies demonstrate that the delivery of peposertib is severely restricted into the CNS as opposed to peripheral organs, by active efflux at the blood-brain barrier (BBB). Peposertib has a low free fraction in the brain and spinal cord, further reducing the active concentration, and distributes to the same degree within different anatomic regions of the brain. However, peposertib is heterogeneously distributed within the metastatic tumor, where its concentration is highest within the tumor core (with disrupted BBB) and substantially lower within the invasive tumor rim (with a relatively intact BBB) and surrounding normal brain. These findings are critical in guiding the potential clinical deployment of peposertib as a radiosensitizing agent for the safe and effective treatment of brain metastases. SIGNIFICANCE STATEMENT: Effective radiosensitization of brain metastases while avoiding toxicity to the surrounding brain is critical in the development of novel radiosensitizers. The central nervous system distribution of peposertib, a potent catalytic subunit of DNA-dependent protein kinase inhibitor, is restricted by active efflux in the normal blood-brain barrier (BBB) but can reach significant concentrations in the tumor core. This finding suggests that peposertib may be an effective radiosensitizer for intracranial tumors with an open BBB, while limited distribution into normal brain will decrease the risk of enhanced radiation injury.
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Heterogeneous delivery across the blood-brain barrier limits the efficacy of an EGFR-targeting antibody drug conjugate in glioblastoma. Neuro Oncol 2021; 23:2042-2053. [PMID: 34050676 PMCID: PMC8643472 DOI: 10.1093/neuonc/noab133] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Antibody drug conjugates (ADCs) targeting the epidermal growth factor receptor (EGFR), such as depatuxizumab mafodotin (Depatux-M), is a promising therapeutic strategy for glioblastoma (GBM) but recent clinical trials did not demonstrate a survival benefit. Understanding the mechanisms of failure for this promising strategy is critically important. METHODS PDX models were employed to study efficacy of systemic vs intracranial delivery of Depatux-M. Immunofluorescence and MALDI-MSI were performed to detect drug levels in the brain. EGFR levels and compensatory pathways were studied using quantitative flow cytometry, Western blots, RNAseq, FISH, and phosphoproteomics. RESULTS Systemic delivery of Depatux-M was highly effective in nine of 10 EGFR-amplified heterotopic PDXs with survival extending beyond one year in eight PDXs. Acquired resistance in two PDXs (GBM12 and GBM46) was driven by suppression of EGFR expression or emergence of a novel short-variant of EGFR lacking the epitope for the Depatux-M antibody. In contrast to the profound benefit observed in heterotopic tumors, only two of seven intrinsically sensitive PDXs were responsive to Depatux-M as intracranial tumors. Poor efficacy in orthotopic PDXs was associated with limited and heterogeneous distribution of Depatux-M into tumor tissues, and artificial disruption of the BBB or bypass of the BBB by direct intracranial injection of Depatux-M into orthotopic tumors markedly enhanced the efficacy of drug treatment. CONCLUSIONS Despite profound intrinsic sensitivity to Depatux-M, limited drug delivery into brain tumor may have been a key contributor to lack of efficacy in recently failed clinical trials.
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Predictors of permanent stoma creation in patients with mid or low rectal cancer: results of a multicentre cohort study with preoperative evaluation of anal function. Colorectal Dis 2020; 22:399-407. [PMID: 31698537 DOI: 10.1111/codi.14898] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/02/2019] [Accepted: 10/08/2019] [Indexed: 12/24/2022]
Abstract
AIM Preoperative factors predictive of permanent stoma creation were investigated in a long-term follow-up of patients with mid or low rectal cancer. METHOD We included patients who underwent radical resection for mid or low rectal cancer with available data for preoperative anal function measured by manometry and Faecal Incontinence Severity Index questionnaire between January 2005 and December 2015 in three tertiary referral hospitals. A permanent stoma was defined as a stoma present until the patient's last follow-up visit or death. Preoperative factors that predicted permanent stoma creation were analysed. RESULTS Over a median follow-up of 57.4 months (range 12-143 months), a permanent stoma was created in 144/577 (25.0%) patients, including 89 (15.4%) who underwent abdominoperineal resection, one (0.2%) who underwent Hartmann's operation without reversal, 15 (2.6%) with a diverting ileostomy at the time of initial sphincter-preserving surgery without undergoing stoma reversal, and 39 (6.8%) who underwent permanent ileostomy formation after sphincter-preserving surgery. Patients with permanent stoma creation had a shorter tumour distance from the anal verge (P < 0.001), larger tumour size (P = 0.020) and higher preoperative Faecal Incontinence Severity Index score (P = 0.020). On multivariable analysis, tumour distance from the anal verge predicted permanent stoma formation (relative risk 0.53 per centimetre increase; 95% confidence interval 0.46-0.60; P < 0.001) but preoperative anal function did not. CONCLUSION Tumour distance from the anal verge was the only preoperative determinant of permanent stoma creation in rectal cancer patients. These data may help mid and low rectal cancer patients understand the need for permanent stoma.
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Taxotere Induces Dephosphorylation of MET in Patient-derived Tumor Models. Anticancer Res 2020; 40:109-119. [PMID: 31892559 DOI: 10.21873/anticanres.13932] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 11/29/2019] [Accepted: 12/02/2019] [Indexed: 11/10/2022]
Abstract
BACKGROUND/AIM Although molecular targeting therapy is an attractive treatment for cancer, resistance eventually develops in most cases. Here, we evaluated chemotherapeutic efficacy on non-small cell lung cancer (NSCLC) with acquired resistance to epidermal growth factor receptor inhibitors mechanistically. MATERIALS AND METHODS Antitumor effects of taxotere were evaluated using multiple models, including xenograft, and patient-derived models developed from adenocarcinoma cancer patients. Protein expressions were analyzed after drug treatment. RESULTS Taxotere inhibited tumor growth of NSCLC cells harboring drug resistance, and reduced the expression of phosphorylated MET proto-oncogene, receptor tyrosine kinase (MET). A tumor-inhibitory effect of taxotere was also demonstrated in vivo in xenografts in mice, patient-derived primary lung tumor cells and patient-derived xenograft with concomitant repression of phosphorylated MET expression. Chemotherapeutic and MET-targeting drug exhibited a synergistic cell growth-inhibitory effect. CONCLUSION These results suggest that the anticancer drug taxane may be an adjuvant for lung tumors exhibiting enhanced signaling of MET networks.
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Evaluation of the Mrp2-mediated flavonoid-drug interaction potential of quercetin in rats and in vitro models. Asian J Pharm Sci 2019; 14:621-630. [PMID: 32104488 PMCID: PMC7032158 DOI: 10.1016/j.ajps.2018.12.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2018] [Revised: 11/30/2018] [Accepted: 12/06/2018] [Indexed: 01/13/2023] Open
Abstract
Quercetin is a biologically active flavonoid that has been used as a popular health supplement. It is reported that quercetin may cause flavonoid-drug interaction mediated by P-glycoprotein, the most predominant efflux transporter. In this study, we comprehensively evaluated the potential of the pharmacokinetic interaction of quercetin mediated by multidrug resistance-associated protein 2 (MRP2), another major efflux transporter. MRP2-transfected MDCKII cells and LS174T cells were used to evaluate the potential inhibition and induction of MRP2 by quercetin in vitro. To evaluate the induction effect of quercetin on Mrp2 in vivo, Mrp2 mRNA expression in rat liver, kidney, and small intestinal tissues was determined after the oral administration of quercetin (50, 100, or 250 mg/kg) for seven days. Mrp2-mediated interaction potential was also evaluated by the pharmacokinetic study of phenolsulfonphthalein in rats after single or multiple doses of quercetin. Additionally, the effect of quercetin on absorption of docetaxel, a P-glycoprotein and CYP3A4 substrate, was also evaluated. Quercetin inhibited the function of MRP2 at 10 µM and induced the mRNA expression of MRP2 at 50 µM in vitro. Additionally, at 100 mg/kg, quercetin markedly increased Mrp2 expression in the small intestine of rats. However, there was no significant change in phenolsulfonphthalein pharmacokinetics due to single- (50, 100, or 250 mg/kg) or multiple-dose (50, 100, or 250 mg/kg for seven days) quercetin co-administration. By contrast, a significant interaction caused by quercetin (100 mg/kg) was observed in the absorption of docetaxel. The results suggested that although quercetin modulates the function and expression of MRP2 in vitro, it may have a low potential of Mrp2-mediated interaction and present negligible safety concerns related to the interaction.
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3334Updated meta-analysis of biodegradable polymer drug-eluting stent versus second-generation durable polymer drug-eluting stent implantations. Eur Heart J 2019. [DOI: 10.1093/eurheartj/ehz745.0086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Background
Data regarding clinical outcomes of biodegradable polymer drug-eluting stent (BP-DES) versus second-generation durable polymer drug-eluting stent (DP-DES) in patients undergoing percutaneous coronary intervention (PCI) are inconclusive.
Purpose
We aimed to perform a meta-analysis to investigate the clinical outcomes of BP-DES compared with second-generation DP-DES in patients who have undergone PCI.
Methods
We searched PubMed, MEDLINE, EMBASE, and Cochrane databases through January 2019 for randomized controlled trials comparing BP-DES with second-generation DP-DES in patients treated with PCI. All-cause death, cardiac death, myocardial infarction (MI), target vessel revascularization (TVR), target lesion revascularization (TLR), definite/probable stent thrombosis (ST) were compared between the groups. Additionally, a landmark analysis with the landmark set at 1 year and a subgroup analysis according to stent characteristics were performed.
Results
Data from 23 trials including 28802 randomized patients were analyzed. At a median follow up of 3.1 years, no significant differences were found in terms of all-cause death (odds ratio [OR] 1.05, 95% confidence interval [CI] 0.95–1.16), cardiac death (OR 1.01, 95% CI 0.87–1.17), MI (OR 0.92, 95% CI 0.82–1.03), TVR (OR 0.97, 95% CI 0.86–1.11), TLR (OR 0.97, 95% CI 0.85–1.11), and definite/probable ST (OR 0.86, 95% CI 0.70–1.07) between the groups. Landmark analysis showed that there were similar risks in all-cause death (OR 1.04, 95% CI 0.93–1.17), cardiac death (OR 1.11, 95% CI 0.92–1.36), MI (OR 0.94, 95% CI 0.79–1.13), TVR (OR 0.95, 95% CI 0.73–1.23), TLR (OR 1.00, 95% CI 0.80–1.24), and definite/probable ST (OR 0.92, 95% CI 0.67–1.28) between the groups. The similar tendency of any study endpoints between the groups was consistent in the subgroup, including stent platform (stainless steel vs. alloy), the drug coating distribution (abluminal vs. circumferential), the polymer degradation period (<6 months vs. >6 months), or the drug release duration (<6 months vs. >6 months) of BP-DES, or the DAPT duration (≥6 months vs. ≥12 months). However, the uses of BP-DES with sirolimus-eluting (OR 0.84, 95% CI 0.72–0.98) or ultrathin strut (defined as <70μm; OR 0.81, 95% CI 0.68–0.97) were predictive for lower risk of MI.
Clinical outcomes
Conclusions
In our updated meta-analysis, BP-DES implantation was associated with comparable clinical outcomes compared with second-generation DP-DES implantation. However, PCI with ultrathin biodegradable polymer sirolimus-eluting stent could reduce the risk of MI.
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P2799Long-term outcomes after percutaneous coronary intervention with biodegradable polymer drug-eluting stent versus second-generation durable polymer drug-eluting stent: evidence from a meta-analysis. Eur Heart J 2019. [DOI: 10.1093/eurheartj/ehz748.1112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Background
The true benefit of biodegradable polymer drug-eluting stent (BP-DES) over second-generation durable polymer drug-eluting stent (DP-DES) expected to be represented during late period of follow-up after percutaneous coronary intervention (PCI), but prior meta-analysis only evaluated short-term outcomes.
Purpose
We aimed to compare the long-term clinical outcomes after PCI with BP-DES versus second-generation DP-DES by a meta-analysis of randomized controlled trials.
Methods
Randomized controlled trials comparing BP-DES with second-generation DP-DES implantations were searched through PubMed, MEDLINE, EMBASE, and Cochrane databases. All-cause death, cardiac death, myocardial infarction (MI), target vessel revascularization (TVR), target lesion revascularization (TLR), and definite/probable stent thrombosis (ST) were compared between the groups. In addition, a landmark analysis with the landmark set at 1-year and a subgroup analysis based on stent characteristics were performed.
Results
Fifteen trials that included a total of 21311 randomized patients with at least 2 years follow-up were analyzed. At a median follow-up of 4.2 years, no significant differences in the risks of all-cause death (odds ratio [OR] 1.03, 95% confidence interval [CI] 0.94–1.14), cardiac death (OR 1.03, 95% CI 0.88–1.20), MI (OR 0.90, 95% CI 0.79–1.01), TVR (OR 0.96, 95% CI 0.82–1.12), TLR (OR 0.97, 95% CI 0.85–1.11), and definite/probable ST (OR 0.84, 95% CI 0.67–1.05) were found between the groups. In the 1-year landmark analysis, the rates of all-cause death (OR 1.04, 95% CI 0.93–1.17), cardiac death (OR 1.11, 95% CI 0.92–1.36), MI (OR 0.94, 95% CI 0.79–1.13), TVR (OR 0.95, 95% CI 0.73–1.23), TLR (OR 1.00, 95% CI 0.80–1.24), and definite/probable ST (OR 0.94, 95% CI 0.67–1.31) were similar between the groups. There were comparable rates of any study endpoints between the groups regardless of stent platform (stainless steel vs. alloy), the polymer degradation period (<6 months vs. >6 months) or the drug release duration (<6 months vs. >6 months) of BP-DES, or the DAPT duration (≥6 months vs. ≥12 months). However, the use of BP-DES with sirolimus eluting (OR 0.82, 95% CI 0.70–0.97), circumferential drug distribution (OR 0.79, 95% CI 0.65–0.96), thin strut (defined as <100μm; OR 0.83, 95% CI 0.70–0.97), or ultrathin strut (defined as <70μm; OR 0.78, 95% CI 0.64–0.94) were associated with lower rates of MI than did second-generation DP-DES. Moreover, BP-DES with circumferential drug distribution (OR 0.82, 95% CI 0.69–0.98) was predictive for reduced rates of TVR.
Clinical outcomes
Conclusions
In this meta-analysis, long-term clinical outcomes were equivalent between BP-DES and second-generation DP-DES implantations. However, among BP-DESs, the improved risks of MI in those with sirolimus eluting, circumferential drug distribution, thin strut, or ultrathin strut and decreased rates of TVR in those with circumferential drug distribution were noted.
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Optimized liquid chromatography-tandem mass spectrometry for Otaplimastat quantification in rat plasma and brain tissue. J Chromatogr Sci 2019; 57:258-264. [PMID: 30566583 DOI: 10.1093/chromsci/bmy109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Accepted: 11/21/2018] [Indexed: 11/12/2022]
Abstract
An optimized liquid chromatography-tandem mass spectrometry method for simple and sensitive quantification of Otaplimastat in rat plasma and brain tissue was developed and validated. Protein precipitation with acetonitrile was selected for sample preparation method based on recovery and matrix effect. The chromatographic separation of the sample was performed on a reverse-phase AQ column with an isocratic mobile phase consisting of 10 mM ammonium acetate (pH 4.0) and acetonitrile (50:50, v/v). The analyte was quantified by multiple reaction monitoring with a Waters Quattro micro™ API mass spectrometer. The lower limits of quantification were 20 ng/mL in plasma and 2 ng/g in brain, with the relative standard deviation % of 7.6 and 8.0% for plasma and brain samples, respectively. Acceptable intra-day and inter-day precisions and accuracies were obtained. Otaplimastat was sufficiently stable under all relevant analytical conditions, including a temperature of 4°C for 24 hr, room temperature 20°C for 24 hr, -80°C for 10 days and three freeze-thaw cycles (each at -80°C for 24 hr), for rat plasma and brain tissue. The validated method was successfully used to measure Otaplimastat concentrations in rat plasma and brain samples.
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1466Prognosis of biodegradable polymer drug-eluting stents versus second-generation durable polymer drug-eluting stents in acute myocardial infarction patients following percutaneous coronary intervention. Eur Heart J 2018. [DOI: 10.1093/eurheartj/ehy565.1466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Abstract 887: The effect of anticancer chemotherapeutics on immune microenvironment of lung adenocarcinoma with EGFR mutation in vivomicroenvironment of lung adenocarcinoma with EGFR mutation in vivo. Cancer Res 2018. [DOI: 10.1158/1538-7445.am2018-887] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Lung cancer is the leading cause of cancer related deaths worldwide. Molecular targeting therapy is an attractive treatment for lung cancer, although it eventually develops resistance in most cases. In this report, we tested taxan antitumor effect on lung adenocarcinomas in vitro and in vivo. It could inhibit cell growth of many NSCLC cells tested, exhibiting reduced expression of c-MET and STAT3. The nascent effect of taxan on lung tumor cells were also proved on patient-derived primary lung tumor cells and patient-derived xenograft model that highly expresses c-MET. The antitumor effect of this chemotherapeutics was also observed on T790M mutant cells. Interestingly, the antitumor effect of taxan was synergistic in combination of c-Met inhibitor on lung tumor cells as well as patient-derived primary lung tumor cells. However, single treatment of taxan was sufficient for halting tumor growth in vivo, as no combinational effect of c-Met inhibitor was obvious. Not only c-Met inhibitor but also taxan reduced phosphorylated c-MET and STAT3, although cytokines on downstream of c-MET and STAT3 were explosively increased in vitro setting resulting in high expression of chemokines/cytokines. Importantly, the effect was not true in in vivo setting, in which the expressions of chemokines/cytokines as well as phosphorylated c-MET and STAT3 were influenced with this agent. These results suggest that taxane is one of the comparative adjuvant for lung tumors exhibiting targeted drug resistance, especially for enhanced signaling of MET-STAT-immuno-microenvironment.
Citation Format: Young-Ah Suh, Hyemin Mun, Sun-Hye Lee, Se-Young Jo, Ju-Hee Oh, Chu-Hee Lee. The effect of anticancer chemotherapeutics on immune microenvironment of lung adenocarcinoma with EGFR mutation in vivomicroenvironment of lung adenocarcinoma with EGFR mutation in vivo [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 887.
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Circadian expression of hepatic drug transporters and their role in the hepatic excretion of phenolsulfonphthalein. Drug Metab Pharmacokinet 2018. [DOI: 10.1016/j.dmpk.2017.11.306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Does the Bed Frame Deflection Occur along with Mattress Deflection during In-Hospital Cardiopulmonary Resuscitation? an Experiment Using Mechanical Devices. HONG KONG J EMERG ME 2017. [DOI: 10.1177/102490791602300205] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Objectives When we perform chest compression on a patient on a bed, the mattress and bed frame can be depressed together with the patient's chest. This study was conducted to assess whether bed frame deflection occurred during chest compressions. Methods We designed a firm bed (“bed like the ground,” BLG) to assess the bed frame deflection in the Stryker Trauma Stretcher (STS) and the ER stretcher cart (ER-SC). The STS included a soft mattress and the ER-SC a hard mattress. We performed 50 continuous chest compressions on the Resusci Anne Skill Reporter with CPRmeter in each experiment. The experiments were done in four settings. Test 1 included the BLG; test 2 included a mattress and backboard on each bed; test 3 included the mattress of each bed and a backboard on the BLG; and test 4 included the mattress of each bed on the BLG. We calculated the mattress and bed frame deflections using the gaps of compression depths between the values measured by Resusci Anne and CPRmeter. Results The mattress deflections of the STS and ER-SC mattress were determined to be 11.2 and 0.67 mm, respectively. The bed frame deflection for the STS and ER-SC were 0.95 and 5.17 mm, respectively. Conclusion The study confirms that bed frame deflection will occur when we perform chest compressions on the manikin lying on a bed. Additionally, the bed frame deflections differ depending on the type of bed. (Hong Kong j.emerg.med. 2016;23:35-41)
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Accuracy of Plain Abdominal Radiography in the Differentiation between Small Bowel Obstruction and Small Bowel Ileus in Acute Abdomen Presenting to Emergency Department. HONG KONG J EMERG ME 2017. [DOI: 10.1177/102490791101800202] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Introduction Our purpose was to evaluate whether plain abdominal radiography (PAR) could accurately differentiate between small bowel obstruction (SBO) and small bowel ileus (SBI) in an emergency setting. We also evaluated the value of known classic signs on the PAR for differentiating between SBO and SBI. Methods This retrospective study included 216 emergency room patients who had small bowel distension (maximal small bowel diameter ≥2.5 cm) on the PAR and who underwent successive abdominal computed tomography. One radiologist and one emergency physician retrospectively reviewed PAR in consensus, unaware of the patients' clinical data; they divided the patients into an SBO group and an SBI group according to the radiographic findings. Presence or numeric values of 10 radiographic signs were also recorded. Final diagnoses of SBO and SBI were established by a combined analysis of medical charts, surgical records, radiographic findings on abdominal computed tomography, and small bowel studies. The differential diagnoses based on PAR and the final diagnoses were compared, and the sensitivity and specificity of PAR were calculated. We also evaluated the differences among 10 radiographic signs between the final SBO and SBI groups. Results Sensitivity and specificity of PAR for SBO were 82.0% and 92.4%, respectively. Among the 10 radiographic signs, all except maximal colon diameter were statistically significant predictors on the final diagnosis. Conclusions PAR is an accurate and effective initial imaging modality for differentiating between SBO and SBI in an emergency setting, and most of the classic radiographic signs have a diagnostic value.
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Oral Administration of (S)-Allyl-l-Cysteine and Aged Garlic Extract to Rats: Determination of Metabolites and Their Pharmacokinetics. PLANTA MEDICA 2017; 83:1351-1360. [PMID: 28561204 DOI: 10.1055/s-0043-111895] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
(S)-Allyl-l-cysteine is the major bioactive compound in garlic. (S)-Allyl-l-cysteine is metabolized to (S)-allyl-l-cysteine sulfoxide, N-acetyl-(S)-allyl-l-cysteine, and N-acetyl-(S)-allyl-l-cysteine sulfoxide after oral administration. An accurate LC-MS/MS method was developed and validated for the simultaneous quantification of (S)-allyl-l-cysteine and its metabolites in rat plasma, and the feasibility of using it in pharmacokinetic studies was tested. The analytes were quantified by multiple reaction monitoring using an atmospheric pressure ionization mass spectrometer. Because significant quantitative interference was observed between (S)-allyl-l-cysteine and N-acetyl-(S)-allyl-l-cysteine as a result of the decomposition of N-acetyl-(S)-allyl-l-cysteine at the detector source, chromatographic separation was required to discriminate (S)-allyl-l-cysteine and its metabolites on a reversed-phase C18 analytical column with a gradient mobile phase consisting of 0.1% formic acid and acetonitrile. The calibration curves of (S)-allyl-l-cysteine, (S)-allyl-l-cysteine sulfoxide, N-acetyl-(S)-allyl-l-cysteine, and N-acetyl-(S)-allyl-l-cysteine sulfoxide were linear over each concentration range, and the lower limits of quantification were 0.1 µg/mL [(S)-allyl-l-cysteine and N-acetyl-(S)-allyl-l-cysteine] and 0.25 µg/mL [(S)-allyl-l-cysteine sulfoxide and N-acetyl-(S)-allyl-l-cysteine sulfoxide]. Acceptable intraday and inter-day precisions and accuracies were obtained at three concentration levels. The method satisfied the regulatory requirements for matrix effects, recovery, and stability. The validated LC-MS/MS method was successfully used to determine the concentration of (S)-allyl-l-cysteine and its metabolites in rat plasma samples after the administration of (S)-allyl-l-cysteine or aged garlic extract.
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Temporal patterns of patient-reported trismus and associated mouth-opening distances in radiotherapy for head and neck cancer: A prospective cohort study. Clin Otolaryngol 2017; 43:22-30. [PMID: 28463432 DOI: 10.1111/coa.12896] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/26/2017] [Indexed: 11/28/2022]
Abstract
OBJECTIVES To identify temporal patterns of patient-reported trismus during the first year post-radiotherapy, and to study their associations with maximal interincisal opening distances (MIOs). DESIGN Single institution case series. SETTING University hospital ENT clinic. PARTICIPANTS One hundred and ninety-six subjects who received radiotherapy (RT) for head and neck cancer (HNC) with or without chemotherapy in 2007-2012 to a total dose of 64.6/68 Gy in 38/34 fractions, respectively. All subjects were prospectively assessed for mouth-opening ability (Gothenburg Trismus Questionnaire (GTQ), European Organization for Research and Treatment of Cancer quality of life Questionnaire (EORTC QLQ-H&N35), and MIO) pre-RT and at 3, 6 and 12 months after RT. MAIN OUTCOME MEASURES Correlations between temporally robust GTQ symptoms and MIO as given by Pearson's correlation coefficients (Pr ); temporally robust GTQ-symptom domains as given by factor analysis; rates of trismus with respect to baseline by risk ratios (RRs). RESULTS Four temporally robust domains were identified: Eating (3-7 symptoms), Jaw (3-7), Pain (2-5) and Quality of Life (QoL, 2-5), and included 2-3 persistent symptoms across all post-RT assessments. The median RR for a moderate/severe (>2/>3) cut-off was the highest for Jaw (3.7/3.6) and QoL (3.2/2.9). The median Pr between temporally robust symptoms and MIO post-radiotherapy was 0.25-0.35/0.34-0.43/0.24-0.31/0.34-0.50 for Eating/Jaw/Pain/QoL, respectively. CONCLUSIONS Mouth-opening distances in patients with HNC post-RT can be understood in terms of associated patient-reported outcomes on trismus-related difficulties. Our data suggest that a reduction in MIO can be expected as patients communicate their mouth-opening status to interfere with private/social life, a clinical warning signal for emerging or worsening trismus as patients are being followed after RT.
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Circadian Clock Is Involved in Regulation of Hepatobiliary Transport Mediated by Multidrug Resistance-Associated Protein 2. J Pharm Sci 2017; 106:2491-2498. [PMID: 28479363 DOI: 10.1016/j.xphs.2017.04.071] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Revised: 04/21/2017] [Accepted: 04/25/2017] [Indexed: 11/25/2022]
Abstract
There has been a growing interest in circadian regulation of the expression and function of drug transporters. In this study, we investigated circadian rhythm in the expression and function of multidrug resistance-associated protein 2 (Mrp2) in mouse liver and involvement of circadian clock in their regulations by using the circadian clock genes (period 1 and period 2) knockout mice. The mRNA and protein expression of Mrp2, P-glycoprotein, and breast cancer resistance protein was measured in the mouse liver at different times of the day. Circadian variation of hepatobiliary excretion of phenolsulfonphthalein, a model substrate of Mrp2, was also investigated in mice. Circadian oscillation of Mrp2 protein expression was clearly observed in the mouse liver with levels down at the light phase and up at the dark phase. The cumulative biliary excretion and biliary clearance of phenolsulfonphthalein from the liver to the bile was 2.37- and 1.74-fold greater in mice administered during the dark phase than in those administered during the light phase, respectively. The circadian oscillation in mRNA expression of Mrp2 disappeared in period 1 and period 2 double knockout mice. These results suggest that the expression and function of Mrp2 show the circadian rhythm, controlled by circadian clock genes.
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Camptocormia with Transient Ischemic Attack. J Mov Disord 2017; 10:62-63. [PMID: 28122426 PMCID: PMC5288663 DOI: 10.14802/jmd.16043] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2016] [Revised: 10/17/2016] [Accepted: 10/31/2016] [Indexed: 11/29/2022] Open
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Polypyrimidine tract-binding protein 1-mediated down-regulation of ATG10 facilitates metastasis of colorectal cancer cells. Cancer Lett 2017; 385:21-27. [DOI: 10.1016/j.canlet.2016.11.002] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2016] [Revised: 11/01/2016] [Accepted: 11/01/2016] [Indexed: 12/21/2022]
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High-Dose Metformin May Increase the Concentration of Atorvastatin in the Liver by Inhibition of Multidrug Resistance-Associated Protein 2. J Pharm Sci 2016; 106:961-967. [PMID: 27964938 DOI: 10.1016/j.xphs.2016.11.020] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2016] [Revised: 11/04/2016] [Accepted: 11/29/2016] [Indexed: 12/22/2022]
Abstract
In this study, we evaluated the effect of coadministered metformin on the biliary excretion and liver concentration of atorvastatin. To investigate the inhibitory effect of metformin on biliary efflux transporters, the transport of atorvastatin in MDCKII-MDR1, BCRP, and MRP2 was evaluated. The effects of metformin on the steady state liver concentration and biliary excretion of atorvastatin and 2-hydroxyatorvastatin were evaluated in SDR and Mrp2-deficient EHBR. Metformin did not inhibit the transport of atorvastatin via BCRP and MDR1. However, metformin significantly inhibited the transport of atorvastatin and 2-hydroxyatorvastatin via MRP2 (apparent IC50 = 12 and 2 μM). Coadministered metformin significantly increased the Kp,liver and Cliver (1.7- and 1.6-fold) and decreased the biliary clearance of atorvastatin (2.7-fold) in SDR, but it did not affect the plasma concentration and total clearance of atorvastatin. Similar effects by metformin were observed for 2-hydroxyatorvastatin. In addition, coadministered metformin did not have any effect in EHBR. Therefore, coadministered metformin increases the liver concentration of atorvastatin via inhibition of the Mrp2 in rats, without affecting the plasma concentration. This "silent interaction" by metformin in atorvastatin and metformin combination therapy may be related to the unnoticeable pharmacological synergism or unpredicted side effects of atorvastatin in the liver.
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CHA<sub>2</sub>DS<sub>2</sub>-VASc Scores are Proportionally Associated with Left Atrial Enlargement and Serum
D-dimer Levels in Patients with Non-valvular Atrial Fibrillation. JOURNAL OF NEUROCRITICAL CARE 2016. [DOI: 10.18700/jnc.160074] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
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Synthesis and Properties of Stretchable Fluorescent Polydiphenylacetylene Derivatives. POLYMER-KOREA 2016. [DOI: 10.7317/pk.2016.40.5.736] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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KIF3A binds to β-arrestin for suppressing Wnt/β-catenin signalling independently of primary cilia in lung cancer. Sci Rep 2016; 6:32770. [PMID: 27596264 PMCID: PMC5011747 DOI: 10.1038/srep32770] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2016] [Accepted: 08/15/2016] [Indexed: 02/08/2023] Open
Abstract
Aberrant Wnt/β-catenin signalling is implicated in the progression of several human cancers, including non-small cell lung cancer (NSCLC). However, mutations in Wnt/β-catenin pathway components are uncommon in NSCLC, and their epigenetic control remains unclear. Here, we show that KIF3A, a member of the kinesin-2 family, plays a role in suppressing Wnt/β-catenin signalling in NSCLC cells. KIF3A knockdown increases both β-catenin levels and transcriptional activity with concomitant promotion of malignant potential, such as increased proliferation and migration and upregulation of stemness markers. Because KIF3A binds β-arrestin, KIF3A depletion allows β-arrestin to form a complex with DVL2 and axin, stabilizing β-catenin. Although primary cilia, whose biogenesis requires KIF3A, are thought to restrain the Wnt response, pharmacological inhibition of ciliogenesis failed to increase β-catenin activity in NSCLC cells. A correlation between KIF3A loss and a poorer NSCLC prognosis as well as β-catenin and cyclin D1 upregulation further suggests that KIF3A suppresses Wnt/β-catenin signalling and tumourigenesis in NSCLC.
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Long-term outcomes of locally or radically resected T1 colorectal cancer. Colorectal Dis 2016; 18:852-60. [PMID: 26589573 DOI: 10.1111/codi.13221] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Accepted: 10/08/2015] [Indexed: 12/11/2022]
Abstract
AIM Little is known about the long-term outcome of T1 colorectal cancer (CRC) following curative resection. The present study addressed the long-term outcome of locally or radically resected T1 CRCs. METHOD A total of 430 patients with T1 CRC who underwent local or radical resection were considered. Unfavourable histological factors were defined as positive resection margin, deep submucosal invasion, vascular invasion, Grade 3 and budding. The patients were classified as low-risk (unfavourable histological factor negative, n = 65) or high-risk (unfavourable histological factor positive, n = 365). RESULTS Over a median follow-up of 78.4 months, disease recurred in 16 (3.7%) patients in the high-risk group, and no recurrence in the low-risk group. Resection type and vascular invasion were significantly associated with recurrence. In the vascular invasion (+) high-risk group, both 5-year disease-free survival rate and 5-year overall survival rate were significantly associated with resection type (radical 94.6%, local 43.8%, P < 0.001, and radical 99.1%, local 66.7%, P < 0.001). In the vascular invasion (-) high-risk group, 5-year disease-free survival rate was also significantly associated with resection type (radical 98.9%, local 84.7%, P = 0.001). However, 5-year overall survival rate was not associated with resection type (radical 98.9%, local 95.2%, P = 0.816). CONCLUSION Local resection may be effective and oncologically safe in low-risk T1 CRC. Although additional surgery should be recommended for the locally resected high-risk T1 CRC cases, intensive surveillance without additional surgery and timely salvage operation may offer another treatment option, if vascular invasion is negative.
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Deproteinization with ZnSO4–Ba(OH)2 reduces the photodegradation of montelukast during plasma sample preparation for HPLC analysis. J LIQ CHROMATOGR R T 2016. [DOI: 10.1080/10826076.2016.1198915] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Lymph node size is not a reliable criterion for predicting nodal metastasis in rectal neuroendocrine tumours. Colorectal Dis 2016; 18:O243-51. [PMID: 27166857 DOI: 10.1111/codi.13377] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/08/2015] [Accepted: 04/12/2016] [Indexed: 02/08/2023]
Abstract
AIM The study was designed to assess the correlation between lymph node (LN) size and LN metastasis in patients with rectal neuroendocrine tumours (NETs). METHOD Forty patients who underwent curative resection with lymphadenectomy for a rectal NET between January 2007 and December 2012 were included. The short and long diameters of entire nodes were microscopically measured using a slide gauge. RESULTS In all, 1052 LNs were collected from the 40 patients, with 49 (4.7%) showing evidence of metastasis. Metastasis-positive LNs had significantly greater long and short diameters (P < 0.001) than metastasis-negative LNs. Of the 49 metastatic LNs, 29 (59.2%) were ≤ 5 mm in largest diameter. In five patients, the largest metastatic LN was only 2-3 mm in diameter. In clinically node-negative (cN0) patients, 18 (51.4%) patients had metastatic LNs (pN1). CONCLUSION The size of LNs containing metastasis varied widely, with some being very small. LN size alone is therefore not a sufficient predictor of tumour metastasis in rectal NETs. Radical surgery with lymphadenectomy should be considered for patients with rectal NETs with high risk factors for LN metastasis, even those without LN enlargement.
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Poster session 3Cell growth, differentiation and stem cells - Heart511The role of the endocannabinoid system in modelling muscular dystrophy cardiac disease with induced pluripotent stem cells.512An emerging role of T lymphocytes in cardiac regenerative processes in heart failure due to dilated cardiomyopathy513Canonical wnt signaling reverses the ‘aged/senescent’ human endogenous cardiac stem cell phenotype514Hippo signalling modulates survival of human induced pluripotent stem cell-derived cardiomyocytes515Biocompatibility of mesenchymal stem cells with a spider silk matrix and its potential use as scaffold for cardiac tissue regeneration516A snapshot of genome-wide transcription in human induced pluripotent stem cell-derived hepatocyte-like cells (iPSC-HLCs)517Can NOS/sGC/cGK1 pathway trigger the differentiation and maturation of mouse embryonic stem cells (ESCs)?518Introduction of external Ik1 to human-induced pluripotent stem cell-derived cardiomyocytes via Ik1-expressing HEK293519Cell therapy of the heart studied using adult myocardial slices in vitro520Enhancement of the paracrine potential of human adipose derived stem cells when cultured as spheroid bodies521Mechanosensitivity of cardiomyocyte progenitor cells: the strain response in 2D and 3D environments522The effect of the vascular-like network on the maturation of the human induced pluripotent stem cell derived cardiomyocytes.Transcriptional control and RNA species - Heart525Gene expression regulation in heart failure: from pathobiology to bioinformatics526Human transcriptome in idiopathic dilated cardiomyopathy - a novel high throughput screening527A high-throghput approach unveils putative miRNA-mediated mitochondria-targeted cardioprotective circuits activated by T3 in the post ischemia reperfusion setting528The effect of uraemia on the expression of miR-212/132 and the calcineurin pathway in the rat heartCytokines and cellular inflammation - Heart531Lack of growth differentiation factor 15 aggravates adverse cardiac remodeling upon pressure-overload in mice532Blocking heteromerization of platelet chemokines ccl5 and cxcl4 reduces inflammation and preserves heart function after myocardial infarction533Is there an association between low-dose aspirin use and clinical outcome in HFPEF? Implications of modulating monocyte function and inflammatory mediator release534N-terminal truncated intracellular matrix metalloproteinase-2 expression in diabetic heart.535Expression of CD39 and CD73 on peripheral T-cell subsets in calcific aortic stenosis536Mast cells in the atrial myocardium of patients with atrial fibrillation: a comparison with patients in sinus rhythm539Characteristics of the inflammatory response in patients with coronary artery disease and arterial hypertension540Pro-inflammatory cytokines as cardiovascular events predictors in rheumatoid arthritis and asymptomatic atherosclerosis541Characterization of FVB/N murinic bone marrow-derived macrophage polarization into M1 and M2 phenotypes542The biological expression and thoracic anterior pain syndromeSignal transduction - Heart545The association of heat shock protein 90 and TGFbeta receptor I is involved in collagen production during cardiac remodelling in aortic-banded mice546Loss of the inhibitory GalphaO protein in the rostral ventrolateral medulla of the brainstem leads to abnormalities in cardiovascular reflexes and altered ventricular excitablitiy547Selenoprotein P regulates pressure overload-induced cardiac remodeling548Study of adenylyl cyclase activity in erythrocyte membranes in patients with chronic heart failure549Direct thrombin inhibitors inhibit atrial myocardium hypertrophy in a rat model of heart failure and atrial remodeling550Tissue factor / FVIIa transactivates the IGF-1R by a Src-dependent phosphorylation of caveolin-1551Notch signaling is differently altered in endothelial and smooth muscle cells of ascending aortic aneurysm patients552Frizzled 5 expression is essential for endothelial proliferation and migration553Modulation of vascular function and ROS production by novel synthetic benzopyran analogues in diabetes mellitusExtracellular matrix and fibrosis - Heart556Cardiac fibroblasts as inflammatory supporter cells trigger cardiac inflammation in heart failure557A role for galectin-3 in calcific aortic valve stenosis558Omega-3 polyunsaturated fatty acids- can they decrease risk for ventricular fibrillation?559Serum levels of elastin derived peptides and circulating elastin-antielastin immune complexes in sera of patients with coronary artery disease560Endocardial fibroelastosis is secondary to hemodynamic alterations in the chick model of hypoplastic left heart syndrome561Dynamics of serum levels of matrix metalloproteinases in primary anterior STEMI patients564Deletion of the alpha-7 nicotinic acetylcholine receptor changes the vascular remodeling induced by transverse aortic constriction in mice.565Extracellular matrix remodelling in response to venous hypertension: proteomics of human varicose veinsIon channels, ion exchangers and cellular electrophysiology - Heart568Microtubule-associated protein RP/EB family member 1 modulates sodium channel trafficking and cardiac conduction569Investigation of electrophysiological abnormalities in a rabbit athlete's heart model570Upregulation of expression of multiple genes in the atrioventricular node of streptozotocin-induced diabetic rat571miR-1 as a regulator of sinoatrial rhythm in endurance training adaptation572Selective sodium-calcium exchanger inhibition reduces myocardial dysfunction associated with hypokalaemia and ventricular fibrillation573Effect of racemic and levo-methadone on action potential of human ventricular cardiomyocytes574Acute temperature effects on the chick embryonic heart functionVasculogenesis, angiogenesis and arteriogenesis577Clinical improvement and enhanced collateral vessel growth after monocyte transplantation in mice578The role of HIF-1 alpha, VEGF and obstructive sleep apnoea in the development of coronary collateral circulation579Initiating cardiac repair with a trans-coronary sinus catheter intervention in an ischemia/reperfusion porcine animal model580Early adaptation of pre-existing collaterals after acute arteriolar and venular microocclusion: an in vivo study in chick chorioallantoic membraneEndothelium583EDH-type responses to the activator of potassium KCa2.3 and KCa3.1 channels SKA-31 in the small mesenteric artery from spontaneously hypertensive rats584The peculiarities of endothelial dysfunction in patients with chronic renocardial syndrome585Endothelial dysfunction, atherosclerosis of the carotid arteries and level of leptin in patient with coronary heart disease in combination with hepatic steatosis depend from body mass index.586Role of non-coding RNAs in thoracic aortic aneurysm associated with bicuspid aortic valve587Cigarette smoke extract abrogates atheroprotective effects of high laminar flow on endothelial function588The prognostic value of anti-connective tissue antibodies in coronary heart disease and asymptomatic atherosclerosis589Novel potential properties of bioactive peptides from spanish dry-cured ham on the endothelium.Lipids592Intermediate density lipoprotein is associated with monocyte subset distribution in patients with stable atherosclerosis593The characteristics of dyslipidemia in rheumatoid arthritisAtherosclerosis596Macrophages differentiated in vitro are heterogeneous: morphological and functional profile in patients with coronary artery disease597Palmitoylethanolamide promotes anti-inflammatory phenotype of macrophages and attenuates plaque formation in ApoE-/- mice598Amiodarone versus esmolol in the perioperative period: an in vitro study of coronary artery bypass grafts599BMPRII signaling of fibrocytes, a mesenchymal progenitor cell population, is increased in STEMI and dyslipidemia600The characteristics of atherogenesis and systemic inflammation in rheumatoid arthritis601Role of adenosine-to-inosine RNA editing in human atherosclerosis602Presence of bacterial DNA in thrombus aspirates of patients with myocardial infarction603Novel E-selectin binding polymers reduce atherosclerotic lesions in ApoE(-/-) mice604Differential expression of the plasminogen receptor Plg-RKT in monocyte and macrophage subsets - possible functional consequences in atherogenesis605Apelin-13 treatment enhances the stability of atherosclerotic plaques606Mast cells are increased in the media of coronary lesions in patients with myocardial infarction and favor atherosclerotic plaque instability607Association of neutrophil to lymphocyte ratio with presence of isolated coronary artery ectasiaCalcium fluxes and excitation-contraction coupling610The coxsackie- and adenovirus receptor (CAR) regulates calcium homeostasis in the developing heart611HMW-AGEs application acutely reduces ICaL in adult cardiomyocytes612Measuring electrical conductibility of cardiac T-tubular systems613Postnatal development of cardiac excitation-contraction coupling in rats614Role of altered Ca2+ homeostasis during adverse cardiac remodeling after ischemia/reperfusion615Experimental study of sarcoplasmic reticulum dysfunction and energetic metabolism in failing myocardium associated with diabetes mellitusHibernation, stunning and preconditioning618Volatile anesthetic preconditioning attenuates ischemic-reperfusion injury in type II diabetic patients undergoing on-pump heart surgery619The effect of early and delayed phase of remote ischemic preconditioning on ischemia-reperfusion injury in the isolated hearts of healthy and diabetic rats620Post-conditioning with 1668-thioate leads to attenuation of the inflammatory response and remodeling with less fibrosis and better left ventricular function in a murine model of myocardial infarction621Maturation-related changes in response to ischemia-reperfusion injury and in effects of classical ischemic preconditioning and remote preconditioningMitochondria and energetics624Phase changes in myocardial mitochondrial respiration caused by hypoxic preconditioning or periodic hypoxic training625Desmin mutations depress mitochondrial metabolism626Methylene blue modulates mitochondrial function and monoamine oxidases-related ROS production in diabetic rat hearts627Doxorubicin modulates the real-time oxygen consumption rate of freshly isolated adult rat and human ventricular cardiomyocytesCardiomyopathies and fibrosis630Effects of genetic or pharmacologic inhibition of the ubiquitin/proteasome system on myocardial proteostasis and cardiac function631Suppression of Wnt signalling in a desmoglein-2 transgenic mouse model for arrhythmogenic cardiomyopathy632Cold-induced cardiac hypertrophy is reversed after thermo-neutral deacclimatization633CD45 is a sensitive marker to diagnose lymphocytic myocarditis in endomyocardial biopsies of living patients and in autopsies634Atrial epicardial adipose tissue derives from epicardial progenitors635Caloric restriction ameliorates cardiac function, sympathetic cardiac innervation and beta-adrenergic receptor signaling in an experimental model of post-ischemic heart failure636High fat diet improves cardiac remodelling and function after extensive myocardial infarction in mice637Epigenetic therapy reduces cardiac hypertrophy in murine models of heart failure638Imbalance of the VHL/HIF signaling in WT1+ Epicardial Progenitors results in coronary vascular defects, fibrosis and cardiac hypertrophy639Diastolic dysfunction is the first stage of the developing heart failure640Colchicine aggravates coxsackievirus B3 infection in miceArterial and pulmonary hypertension642Osteopontin as a marker of pulmonary hypertension in patients with coronary heart disease combined with chronic obstructive pulmonary disease643Myocardial dynamic stiffness is increased in experimental pulmonary hypertension partly due to incomplete relaxation644Hypotensive effect of quercetin is possibly mediated by down-regulation of immunotroteasome subunits in aorta of spontaneously hypertensive rats645Urocortin-2 improves right ventricular function and attenuates experimental pulmonary arterial hypertension646A preclinical evaluation of the anti-hypertensive properties of an aqueous extract of Agathosma (Buchu)Biomarkers648The adiponectin level in hypertensive females with rheumatoid arthritis and its relationship with subclinical atherosclerosis649Markers for identification of renal dysfunction in the patients with chronic heart failure650cardio-hepatic syndromes in chronic heart failure: North Africa profile651To study other biomarkers that assess during myocardial infarction652Interconnections of apelin levels with parameters of lipid metabolism in hypertension patients653Plasma proteomics in hypertension: prediction and follow-up of albuminuria during chronic renin-angiotensin system suppression654Soluble RAGE levels in plasma of patients with cerebrovascular events. Cardiovasc Res 2016. [DOI: 10.1093/cvr/cvw150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Abstract
Objectives This study was conducted to evaluate the cytokine-release kinetics of platelet-rich plasma (PRP) according to different activation protocols. Methods Two manual preparation procedures (single-spin (SS) at 900 g for five minutes; double-spin (DS) at 900 g for five minutes and then 1500 g for 15 minutes) were performed for each of 14 healthy subjects. Both preparations were tested for platelet activation by one of three activation protocols: no activation, activation with calcium (Ca) only, or calcium with a low dose (50 IU per 1 ml PRP) of thrombin. Each preparation was divided into four aliquots and incubated for one hour, 24 hours, 72 hours, and seven days. The cytokine-release kinetics were evaluated by assessing PDGF, TGF, VEGF, FGF, IL-1, and MMP-9 concentrations with bead-based sandwich immunoassay. Results The concentration of cytokine released from PRP varied over time and was influenced by various activation protocols. Ca-only activation had a significant effect on the DS PRPs (where the VEGF, FGF, and IL-1 concentrations were sustained) while Ca/thrombin activation had effects on both SS and DS PRPs (where the PDGF and VEGF concentrations were sustained and the TGF and FGF concentrations were short). The IL-1 content showed a significant increase with Ca-only or Ca/thrombin activation while these activations did not increase the MMP-9 concentration. Conclusion The SS and DS methods differed in their effect on cytokine release, and this effect varied among the cytokines analysed. In addition, low dose of thrombin/calcium activation increased the overall cytokine release of the PRP preparations over seven days, relative to that with a calcium-only supplement or non-activation. Cite this article: Professor J. H. Oh. Cytokine-release kinetics of platelet-rich plasma according to various activation protocols. Bone Joint Res 2016;5:37–45. DOI: 10.1302/2046-3758.52.2000540
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Designing of the fixed-dose gastroretentive bilayer tablet for sustained release of metformin and immediate release of atorvastatin. Drug Dev Ind Pharm 2015; 42:340-9. [DOI: 10.3109/03639045.2015.1096279] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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Role of drug transporters: an overview based on knockout animal model studies. JOURNAL OF PHARMACEUTICAL INVESTIGATION 2015. [DOI: 10.1007/s40005-015-0178-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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The measurement of bone mineral density of bilateral proximal humeri using DXA in patients with unilateral rotator cuff tear. Osteoporos Int 2014; 25:2639-48. [PMID: 25027108 DOI: 10.1007/s00198-014-2795-1] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2013] [Accepted: 06/24/2014] [Indexed: 02/03/2023]
Abstract
UNLABELLED We propose that the measurement of the bone mineral density (BMD) of the proximal humerus be standardized using the dual energy X-ray absorptiometry (DXA) in patients supposed to undergo rotator cuff repair surgery as well as those with the fracture of the proximal humerus as the BMD of the proximal humerus is decreased in these patients. INTRODUCTION We propose that the measurement of the BMD of the proximal humerus be standardized using the DXA in patients who are supposed to undergo rotator cuff repair surgery as well as those with the fracture of the proximal humerus. METHODS We conducted the prospective study in 213 patients with unilateral rotator cuff tear but without contralateral shoulder pain or disease. In these patients, we preoperatively measured the BMD of the bilateral proximal humeri with a repeat measurement in 20 patients. We predefined three regions of interest (ROIs) in the proximal humerus with the consideration of the rotator cuff repair surgery as well as proximal humeral fractures. RESULTS The measurement of the BMD of the proximal humerus using the DXA showed excellent reliability (intraclass correlation coefficient > .90). BMD values of all three ROIs in the affected shoulder were significantly lower than those in asymptomatic shoulder (all p < 0.05). In female patients, the BMD values of ROIs in bilateral shoulder were significantly lower than those in male patients (all p < 0.001). In multiple regressions, however, there were no significant correlations between other clinical characteristics, except for the gender, and the BMD of GT in the affected shoulder. CONCLUSIONS It is imperative that the bone quality of the proximal humerus be accurately evaluated prior to surgery in patients who are supposed to undergo rotator cuff repair using suture anchors as well as in those with proximal humeral fractures. This is because the BMD of the proximal humerus is decreased in these patients.
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Sample preparation for liquid chromatographic analysis of phytochemicals in biological fluids. PHYTOCHEMICAL ANALYSIS : PCA 2014; 25:314-330. [PMID: 24375623 DOI: 10.1002/pca.2484] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2013] [Revised: 10/04/2013] [Accepted: 10/04/2013] [Indexed: 06/03/2023]
Abstract
INTRODUCTION Natural products have been used traditionally for the treatment and prevention of diseases for thousands of years and are nowadays consumed as dietary supplements and herbal medicine. To ensure the safe and effective use of these herbal products, information about bioavailability of active compounds in plasma or target tissues should be provided via validated analytical methods combined with appropriate sampling methods. OBJECTIVE To provide comprehensive and abridged information about sample preparation methods for the quantification of phytochemicals in biological samples using liquid chromatography analysis. METHODS Sample pre-treatment procedures used in analytical methods for in vivo pharmacokinetic studies of natural compounds or herbal medicines were reviewed. These were categorised according to the biological matrices (plasma, bile, urine, faeces and tissues) and sample clean-up processes (protein precipitation, liquid-liquid extraction and solid-phase extraction). RESULTS Although various kinds of sample pre-treatment methods have been developed, liquid-liquid extraction is still widely used and solid-phase extraction is becoming increasingly popular because of its efficiency for extensive clean up of complex matrix samples. However, protein precipitation is still favoured due to its simplicity. CONCLUSION Sample treatment for phytochemical analysis in biological fluids is an indispensable and critical step to obtain high quality results. This step could dominate the overall analytical process because both the duration of the process as well as the reliability of the data depend in large part on its efficiency. Thus, special attention should be given to the choice of a proper sample treatment method that targets analytes and their biomatrix.
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Recurrent syncope associated with idiopathic jugular vein stenosis. Report of a young female patient. Herz 2014; 40:722-4. [PMID: 24938218 DOI: 10.1007/s00059-014-4074-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2013] [Revised: 11/15/2013] [Accepted: 02/04/2014] [Indexed: 10/25/2022]
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SU-E-J-62: Estimating Plausible Treatment Course Dose Distributions by Accounting for Registration Uncertainty and Organ Motion. Med Phys 2014. [DOI: 10.1118/1.4888114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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WE-G-BRD-05: Is “New Radiobiology” Needed to Account for the Anti-Tumor Efficacy of Hypofractionated Lung SBRT? Med Phys 2014. [DOI: 10.1118/1.4889489] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Effects of Rashba and Dresselhaus spin-orbit interactions on the ground state of two-dimensional localized spins. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2014; 26:196005. [PMID: 24762988 DOI: 10.1088/0953-8984/26/19/196005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Starting with the indirect exchange model influenced by the Rashba and the Dresselhaus spin-orbit interactions, we derive the Dzyaloshinskii-Moriya interaction of localized spins. The strength of the Dzyaloshinskii-Moriya interaction is compared with that of the Heisenberg exchange term as a function of atomic distance. Using the calculated interaction strengths, we discuss the formation of various atomic ground states as a function of temperature and external magnetic field. By plotting the magnetic field-temperature phase diagram, we present approximate phase boundaries between the spiral, Skyrmion and ferromagnetic states of the two-dimensional weak ferromagnetic system.
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Dopaminergic manipulations and its effects on neurogenesis and motor function in a transgenic mouse model of Huntington's disease. Neurobiol Dis 2014; 66:19-27. [PMID: 24561069 DOI: 10.1016/j.nbd.2014.02.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2013] [Revised: 01/29/2014] [Accepted: 02/10/2014] [Indexed: 11/28/2022] Open
Abstract
Huntington's disease (HD) is an inherited neurodegenerative disorder that is classically defined by a triad of movement and cognitive and psychiatric abnormalities with a well-established pathology that affects the dopaminergic systems of the brain. This has classically been described in terms of an early loss of dopamine D2 receptors (D2R), although interestingly the treatments most effectively used to treat patients with HD block these same receptors. We therefore sought to examine the dopaminergic system in HD not only in terms of striatal function but also at extrastriatal sites especially the hippocampus, given that transgenic (Tg) mice also exhibit deficits in hippocampal-dependent cognitive tests and a reduction in adult hippocampal neurogenesis. We showed that there was an early reduction of D2R in both the striatum and dentate gyrus (DG) of the hippocampus in the R6/1 transgenic HD mouse ahead of any overt motor signs and before striatal neuronal loss. Despite downregulation of D2Rs in these sites, further reduction of the dopaminergic input to these sites by either medial forebrain bundle lesions or receptor blockade using sulpiride was able to improve both deficits in motor performance and adult hippocampal neurogenesis. In contrast, a reduction in dopaminergic innervation of the neurogenic niches resulted in impaired neurogenesis in healthy WT mice. This study therefore provides evidence that D2R blockade improves hippocampal and striatal deficits in HD mice although the underlying mechanism for this is unclear, and suggests that agents working within this network may have greater effects than previously thought.
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4-O-methylhonokiol, a PPARγ agonist, inhibits prostate tumour growth: p21-mediated suppression of NF-κB activity. Br J Pharmacol 2013; 168:1133-45. [PMID: 23043610 DOI: 10.1111/j.1476-5381.2012.02235.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2012] [Revised: 08/22/2012] [Accepted: 09/05/2012] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND AND PURPOSE The effects of 4-O-methylhonokiol (MH), a constituent of Magnolia officinalis, were investigated on human prostate cancer cells and its mechanism of action elucidated. EXPERIMENTAL APPROACH The anti-cancer effects of MH were examined in prostate cancer and normal cells. The effects were validated in vivo using a mouse xenograft model. KEY RESULTS MH increased the expression of PPARγ in prostate PC-3 and LNCap cells. The pull-down assay and molecular docking study indicated that MH directly binds to PPARγ. MH also increased transcriptional activity of PPARγ but decreased NF-κB activity. MH inhibited the growth of human prostate cancer cells, an effect attenuated by the PPARγ antagonist GW9662. MH induced apoptotic cell death and this was related to G(0) -G(1) phase cell cycle arrest. MH increased the expression of the cell cycle regulator p21, and apoptotic proteins, whereas it decreased phosphorylation of Rb and anti-apoptotic proteins. Transfection of PC3 cells with p21 siRNA or a p21 mutant plasmid on the cyclin D1/ cycline-dependent kinase 4 binding site abolished the effects of MH on cell growth, cell viability and related protein expression. In the animal studies, MH inhibited tumour growth, NF-κB activity and expression of anti-apoptotic proteins, whereas it increased the transcriptional activity and expression of PPARγ, and the expression of apoptotic proteins and p21 in tumour tissues. CONCLUSIONS AND IMPLICATION MH inhibits growth of human prostate cancer cells through activation of PPARγ, suppression of NF-κB and arrest of the cell cycle. Thus, MH might be a useful tool for treatment of prostate cancer.
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Effects of experimental hyperlipidemia on the pharmacokinetics of tadalafil in rats. JOURNAL OF PHARMACY AND PHARMACEUTICAL SCIENCES 2013; 15:528-37. [PMID: 23106956 DOI: 10.18433/j35p59] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
PURPOSE Hyperlipidemia is associated with an increased risk of erectile dysfunction. In this study, we investigated the effects of hyperlipidemia on the pharmacokinetics of tadalafil, a novel therapeutic agent for erectile dysfunction, in rats with experimental hyperlipidemia. METHODS Tadalafil (1 mg/kg) was administered to control rats and rats with poloxamer-407-induced hyperlipidemia (1 g/kg, i.p.). In addition, we performed in vitro studies to determine the hepatic metabolism in S9 fractions, intestinal absorption, and plasma protein binding. RESULTS Hyperlipidemia dramatically increased tadalafil's the total area under the plasma concentration-time curve from time 0 to infinity after intravenous (2.09-fold) and oral (11.9-fold) administration, and decreased total body clearance (0.537-fold) and apparent volume of distribution at the steady state (0.438-fold) after intravenous administration of tadalafil. Further, we observed decreased in vitro hepatic S9 metabolism, intestinal first-pass metabolism, and unbound fraction of tadalafil. CONCLUSIONS The alterations in the pharmacokinetics of tadalafil observed in rats with poloxamer 407-induced hyperlipidemia may be attributable to a decrease in hepatic and intestinal metabolism and unbound fraction of tadalafil in the plasma. These findings have potential therapeutic implications for predicting the pharmacokinetic responses of humans to hyperlipidemia. This article is open to POST-PUBLICATION REVIEW. Registered readers (see "For Readers") may comment by clicking on ABSTRACT on the issue's contents page.
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