Tertiary survey in polytrauma patients should be an ongoing process.

PubMed

Ferree, Steven; Houwert, Roderick M; van Laarhoven, Jacqueline J E M; Smeeing, Diederik P J; Leenen, Luke P H; Hietbrink, Falco

2016-04-01

Due to prioritisation in the initial trauma care, non-life threatening injuries can be overlooked or temporally neglected. Polytrauma patients in particular might be at risk for delayed diagnosed injuries (DDI). Studies that solely focus on DDI in polytrauma patients are not available. Therefore the aim of this study was to analyze DDI and determine risk factors associated with DDI in polytrauma patients. In this single centre retrospective cohort study, patients were considered polytrauma when the Injury Severity Score was ≥ 16 as a result of injury in at least 2 body regions. Adult polytrauma patients admitted from 2007 until 2012 were identified. Hospital charts were reviewed to identify DDI. 1416 polytrauma patients were analyzed of which 12% had DDI. Most DDI were found during initial hospital admission after tertiary survey (63%). Extremities were the most affected regions for all types of DDI (78%) with the highest intervention rate (35%). Most prevalent DDI were fractures of the hand (54%) and foot (38%). In 2% of all patients a DDI was found after discharge, consisting mainly of injuries other than a fracture. High energy trauma mechanism (OR 1.8, 95% CI 1.2-2.7), abdominal injury (OR 1.5, 95% CI 1.1-2.1) and extremity injuries found during initial assessment (OR 2.3, 95% CI 1.6-3.3) were independent risk factors for DDI. In polytrauma patients, most DDI were found during hospital admission but after tertiary survey. This demonstrates that the tertiary survey should be an ongoing process and thus repeated daily in polytrauma patients. Most frequent DDI were extremity injuries, especially injuries of the hand and foot. Copyright © 2015 Elsevier Ltd. All rights reserved.

The Distress Disclosure Index: a research review and multitrait-multimethod examination.

PubMed

Kahn, Jeffrey H; Hucke, Brandy E; Bradley, Allyson M; Glinski, Austin J; Malak, Brittany L

2012-01-01

The Distress Disclosure Index (DDI; J. H. Kahn & R. M. Hessling, 2001) is a brief self-report measure of one's tendency to disclose personally distressing information. The purpose of this article was to summarize what is known about the DDI, present new validity evidence, and make recommendations for use of the DDI. This article reviews research on the DDI from the past decade that indicates that distress disclosure is associated with well-being, professional help-seeking attitudes and intentions, and success in brief psychotherapy. On the basis of the reviewed literature, the authors report a reliability generalization study of DDI scores that strongly supports the internal consistency and test-retest reliability of DDI scores, and they review criterion-related and construct validity evidence. Next, the authors present a new multitrait-multimethod validity study of the DDI. Participants (N = 153) and peer informants (N = 153)--one per participant--completed paper-and-pencil questionnaire packets. Convergent validity of self-reported DDI scores was supported by a strong association with self-reports of emotional self-disclosure in response to a specific, unpleasant event, and self- and peer reports on the DDI were moderately correlated. DDI scores were not strongly associated with cognitive reappraisal and ambivalence over emotional expression, thus supporting discriminant validity. DDI scores were strongly associated with expressive suppression, and correlations between DDI scores and affect, depression symptoms, coping, and emotional expressivity were similar to those found with expressive suppression. The authors offer possible hypotheses explaining the overlap between distress disclosure and expressive suppression and present recommendations for future use of the DDI. (c) 2012 APA, all rights reserved.

Implications of intercorrelation between hepatic CYP3A4-CYP2C8 enzymes for the evaluation of drug-drug interactions: a case study with repaglinide.

PubMed

Doki, Kosuke; Darwich, Adam S; Achour, Brahim; Tornio, Aleksi; Backman, Janne T; Rostami-Hodjegan, Amin

2018-05-01

Statistically significant positive correlations are reported for the abundance of hepatic drug-metabolizing enzymes. We investigate, as an example, the impact of CYP3A4-CYP2C8 intercorrelation on the predicted interindividual variabilities of clearance and drug-drug interactions (DDIs) for repaglinide using physiologically based pharmacokinetic (PBPK) modelling. PBPK modelling and simulation were employed using Simcyp Simulator (v15.1). Virtual populations were generated assuming intercorrelations between hepatic CYP3A4-CYP2C8 abundances derived from observed values in 24 human livers. A repaglinide PBPK model was used to predict PK parameters in the presence and absence of gemfibrozil in virtual populations, and the results were compared with a clinical DDI study. Coefficient of variation (CV) of oral clearance was 52.5% in the absence of intercorrelation between CYP3A4-CYP2C8 abundances, which increased to 54.2% when incorporating intercorrelation. In contrast, CV for predicted DDI (as measured by AUC ratio before and after inhibition) was reduced from 46.0% in the absence of intercorrelation between enzymes to 43.8% when incorporating intercorrelation: these CVs were associated with 5th/95th percentiles (2.48-11.29 vs. 2.49-9.69). The range of predicted DDI was larger in the absence of intercorrelation (1.55-77.06) than when incorporating intercorrelation (1.79-25.15), which was closer to clinical observations (2.6-12). The present study demonstrates via a systematic investigation that population-based PBPK modelling incorporating intercorrelation led to more consistent estimation of extreme values than those observed in interindividual variabilities of clearance and DDI. As the intercorrelations more realistically reflect enzyme abundances, virtual population studies involving PBPK and DDI should avoid using Monte Carlo assignment of enzyme abundance. © 2018 The British Pharmacological Society.

Towards a Best Practice Approach in PBPK Modeling: Case Example of Developing a Unified Efavirenz Model Accounting for Induction of CYPs 3A4 and 2B6

PubMed Central

Ke, A; Barter, Z; Rowland‐Yeo, K

2016-01-01

In this study, we present efavirenz physiologically based pharmacokinetic (PBPK) model development as an example of our best practice approach that uses a stepwise approach to verify the different components of the model. First, a PBPK model for efavirenz incorporating in vitro and clinical pharmacokinetic (PK) data was developed to predict exposure following multiple dosing (600 mg q.d.). Alfentanil i.v. and p.o. drug‐drug interaction (DDI) studies were utilized to evaluate and refine the CYP3A4 induction component in the liver and gut. Next, independent DDI studies with substrates of CYP3A4 (maraviroc, atazanavir, and clarithromycin) and CYP2B6 (bupropion) verified the induction components of the model (area under the curve [AUC] ratios within 1.0–1.7‐fold of observed). Finally, the model was refined to incorporate the fractional contribution of enzymes, including CYP2B6, propagating autoinduction into the model (Racc 1.7 vs. 1.7 observed). This validated mechanistic model can now be applied in clinical pharmacology studies to prospectively assess both the victim and perpetrator DDI potential of efavirenz. PMID:27435752

Risk Assessment Using Cytochrome P450 Time-Dependent Inhibition Assays at Single Time and Concentration in the Early Stage of Drug Discovery.

PubMed

Kosaka, Mai; Kosugi, Yohei; Hirabayashi, Hideki

2017-09-01

In this article, we proposed a risk assessment strategy for CYP3A time-dependent inhibition (TDI) during drug discovery based on a thorough retrospective study of 13 reference drugs, some of which are known to have in vitro TDI potential but have unknown clinical relevance. First, the traditional parameter k inact /K I , recommended by regulatory authorities for necessity decision making in clinical drug-drug interaction (DDI) studies, was investigated as a predictive index for clinical TDI liability. The cutoff value of 1.1 for k inact /K I , established by the Food and Drug Administration, tended to produce false-positive prediction results for clinical DDI occurrence. The value of 1.25 recommended in the European Medicines Evaluation Agency draft guideline yielded better predictions with only 1 false negative for diltiazem. Second, to enable earlier risk assessment, remaining activity, defined as the residual CYP3A activity in vitro obtained in the screening conditions, was investigated as an alternative index. As a result, the ratios of unbound C max or area under the curve to remaining activity precisely predicted clinical DDI occurrence. In conclusion, we demonstrated the predictive power of k inact /K I and remaining activity values for clinical DDIs. These findings provide insights that enable TDI risk assessment, even during drug discovery. Copyright © 2017 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

Potential drug-drug interactions with antiepileptic drugs in Medicaid recipients.

PubMed

Dickson, Michael; Bramley, Thomas J; Kozma, Chris; Doshi, Dilesh; Rupnow, Marcia F T

2008-09-15

The frequency of potential drug-drug interactions (DDIs) between antiepileptic drugs (AEDs) and other (non-AED) medications in Medicaid patients taking newer AED monotherapy, older AED monotherapy, and combinations of AED treatment was studied. A retrospective, observational study was conducted using administrative claims obtained from South Carolina Medicaid. Patients were included in the analysis if they (1) had at least one prescription for an AED between January 1, 2004, and December 31, 2004, (2) were taking a specific AED for at least 60 days, (3) had at least one epilepsy diagnosis during the 6 months before or during the enrollment period, and (4) were enrolled in Medicaid for at least 11 of the 12 months of the follow-up period. Possible DDI exposure was defined as 10 days of overlap between an AED and a non-AED known to have the potential to cause a clinically relevant interaction. A total of 4955 patients met the inclusion criteria. Approximately 45% of patients receiving monotherapy with an older AED had a potential DDI, compared with 3.9% receiving a newer AED. An average of 0.08 potential DDI per year of exposure occurred in the newer AED monotherapy cohort compared with 1.18 in the older AED monotherapy cohort. The most common potential interaction category was a decreased concentration of the non-AED. Older AEDs were associated with a greater likelihood of a potential DDI than were newer AEDs. Further research is needed to elucidate the relationship between the occurrence of potential DDIs and actual clinically relevant consequences.

Pharmacogenetics of drug-drug interaction and drug-drug-gene interaction: a systematic review on CYP2C9, CYP2C19 and CYP2D6.

PubMed

Bahar, Muh Akbar; Setiawan, Didik; Hak, Eelko; Wilffert, Bob

2017-05-01

Currently, most guidelines on drug-drug interaction (DDI) neither consider the potential effect of genetic polymorphism in the strength of the interaction nor do they account for the complex interaction caused by the combination of DDI and drug-gene interaction (DGI) where there are multiple biotransformation pathways, which is referred to as drug-drug-gene interaction (DDGI). In this systematic review, we report the impact of pharmacogenetics on DDI and DDGI in which three major drug-metabolizing enzymes - CYP2C9, CYP2C19 and CYP2D6 - are central. We observed that several DDI and DDGI are highly gene-dependent, leading to a different magnitude of interaction. Precision drug therapy should take pharmacogenetics into account when drug interactions in clinical practice are expected.

Information Technology-Based Interventions to Improve Drug-Drug Interaction Outcomes: A Systematic Review on Features and Effects.

PubMed

Nabovati, Ehsan; Vakili-Arki, Hasan; Taherzadeh, Zhila; Saberi, Mohammad Reza; Medlock, Stephanie; Abu-Hanna, Ameen; Eslami, Saeid

2017-01-01

The purpose of this systematic review was to identify features and effects of information technology (IT)-based interventions on outcomes related to drug-drug interactions (DDI outcomes). A literature search was conducted in Medline, EMBASE, and the Cochrane Library for published English-language studies. Studies were included if a main outcome was related to DDIs, the intervention involved an IT-based system, and the study design was experimental or observational with controls. Study characteristics, including features and effects of IT-based interventions, were extracted. Nineteen studies comprising five randomized controlled trials (RCT), five non-randomized controlled trials (NRCT) and nine observational studies with controls (OWC) were included. Sixty-four percent of prescriber-directed interventions, and all non-prescriber interventions, were effective. Each of the following characteristics corresponded to groups of studies of which a majority were effective: automatic provision of recommendations within the providers' workflow, intervention at the time of decision-making, integration into other systems, and requiring the reason for not following the recommendations. Only two studies measured clinical outcomes: an RCT that showed no significant improvement and an OWC that showed improvement, but did not statistically assess the effect. Most studies that measured surrogate outcomes (e.g. potential DDIs) and other outcomes (e.g. adherence to alerts) showed improvements. IT-based interventions improve surrogate clinical outcomes and adherence to DDI alerts. However, there is lack of robust evidence about their effectiveness on clinical outcomes. It is recommended that researchers consider the identified features of effective interventions in the design of interventions and evaluate the effectiveness on DDI outcomes, particularly clinical outcomes.

Potential Drug-Drug Interactions in a Cohort of Elderly, Polymedicated Primary Care Patients on Antithrombotic Treatment.

PubMed

Schneider, Katharina Luise; Kastenmüller, Kathrin; Weckbecker, Klaus; Bleckwenn, Markus; Böhme, Miriam; Stingl, Julia Carolin

2018-06-01

Drug-drug interactions (DDIs) are an important risk factor for adverse drug reactions. Older, polymedicated patients are particularly affected. Although antithrombotics have been detected as high-risk drugs for DDIs, data on older patients exposed to them are scarce. Baseline data of 365 IDrug study outpatients (≥ 60 years, use of an antithrombotic and one or more additional long-term drug) were analyzed regarding potential drug-drug interactions (pDDIs) with a clinical decision support system. Data included prescription and self-medication drugs. The prevalence of having one or more pDDI was 85.2%. The median number of alerts per patient was three (range 0-17). For 58.4% of the patients, potential severe/contraindicated interactions were detected. Antiplatelets and non-steroidal anti-inflammatory drugs (NSAIDs) showed the highest number of average pDDI alert involvements per use (2.9 and 2.2, respectively). For NSAIDs, also the highest average number of severe/contraindicated alert involvements per use (1.2) was observed. 91.8% of all pDDI involvements concerned the 25 most frequently used drug classes. 97.5% of the severe/contraindicated pDDIs were attributed to only nine different potential clinical manifestations. The most common management recommendation for severe/contraindicated pDDIs was to intensify monitoring. Number of drugs was the only detected factor significantly associated with increased number of pDDIs (p < 0.001). The findings indicate a high risk for pDDIs in older, polymedicated patients on antithrombotics. As a consequence of patients' frequently similar drug regimens, the variety of potential clinical manifestations was small. Awareness of these pDDI symptoms and the triggering drugs as well as patients' self-medication use may contribute to increased patient safety.

Improving Spoken Language Outcomes for Children With Hearing Loss: Data-driven Instruction.

PubMed

Douglas, Michael

2016-02-01

To assess the effects of data-driven instruction (DDI) on spoken language outcomes of children with cochlear implants and hearing aids. Retrospective, matched-pairs comparison of post-treatment speech/language data of children who did and did not receive DDI. Private, spoken-language preschool for children with hearing loss. Eleven matched pairs of children with cochlear implants who attended the same spoken language preschool. Groups were matched for age of hearing device fitting, time in the program, degree of predevice fitting hearing loss, sex, and age at testing. Daily informal language samples were collected and analyzed over a 2-year period, per preschool protocol. Annual informal and formal spoken language assessments in articulation, vocabulary, and omnibus language were administered at the end of three time intervals: baseline, end of year one, and end of year two. The primary outcome measures were total raw score performance of spontaneous utterance sentence types and syntax element use as measured by the Teacher Assessment of Spoken Language (TASL). In addition, standardized assessments (the Clinical Evaluation of Language Fundamentals--Preschool Version 2 (CELF-P2), the Expressive One-Word Picture Vocabulary Test (EOWPVT), the Receptive One-Word Picture Vocabulary Test (ROWPVT), and the Goldman-Fristoe Test of Articulation 2 (GFTA2)) were also administered and compared with the control group. The DDI group demonstrated significantly higher raw scores on the TASL each year of the study. The DDI group also achieved statistically significant higher scores for total language on the CELF-P and expressive vocabulary on the EOWPVT, but not for articulation nor receptive vocabulary. Post-hoc assessment revealed that 78% of the students in the DDI group achieved scores in the average range compared with 59% in the control group. The preliminary results of this study support further investigation regarding DDI to investigate whether this method can consistently and significantly improve the achievement of children with hearing loss in spoken language skills.

Prevalence of acid-reducing agents (ARA) in cancer populations and ARA drug-drug interaction potential for molecular targeted agents in clinical development.

PubMed

Smelick, Gillian S; Heffron, Timothy P; Chu, Laura; Dean, Brian; West, David A; Duvall, Scott L; Lum, Bert L; Budha, Nageshwar; Holden, Scott N; Benet, Leslie Z; Frymoyer, Adam; Dresser, Mark J; Ware, Joseph A

2013-11-04

Acid-reducing agents (ARAs) are the most commonly prescribed medications in North America and Western Europe. There are currently no data describing the prevalence of their use among cancer patients. However, this is a paramount question due to the potential for significant drug-drug interactions (DDIs) between ARAs, most commonly proton pump inhibitors (PPIs), and orally administered cancer therapeutics that display pH-dependent solubility, which may lead to decreased drug absorption and decreased therapeutic benefit. Of recently approved orally administered cancer therapeutics, >50% are characterized as having pH-dependent solubility, but there are currently no data describing the potential for this ARA-DDI liability among targeted agents currently in clinical development. The objectives of this study were to (1) determine the prevalence of ARA use among different cancer populations and (2) investigate the prevalence of orally administered cancer therapeutics currently in development that may be liable for an ARA-DDI. To address the question of ARA use among cancer patients, a retrospective cross-sectional analysis was performed using two large healthcare databases: Thomson Reuters MarketScan (N = 1,776,443) and the U.S. Department of Veterans Affairs (VA, N = 1,171,833). Among all cancer patients, the total prevalence proportion of ARA use (no. of cancer patients receiving an ARA/total no. of cancer patients) was 20% and 33% for the MarketScan and VA databases, respectively. PPIs were the most commonly prescribed agent, comprising 79% and 65% of all cancer patients receiving a prescription for an ARA (no. of cancer patients receiving a PPI /no. of cancer patients receiving an ARA) for the MarketScan and VA databases, respectively. To estimate the ARA-DDI liability of orally administered molecular targeted cancer therapeutics currently in development, two publicly available databases, (1) Kinase SARfari and (2) canSAR, were examined. For those orally administered clinical candidates that had available structures, the pKa's and corresponding relative solubilities were calculated for a normal fasting pH of 1.2 and an "ARA-hypochlorhydric" pH of 4. Taking calculated pKa's and relative solubilities into consideration, clinical candidates were classified based on their risk for an ARA-DDI. More than one-quarter (28%) of the molecules investigated are at high risk for an ARA-DDI, and of those high risk molecules, nearly three-quarters (73%) are being clinically evaluated for at least one of five cancer types with the highest prevalence of ARA use (gastrointestinal, pancreatic, lung, glioblastoma multiforme, gastrointestinal stromal tumor (GIST)). These data strongly suggest that with the clinical development of ARA-DDI-susceptible cancer therapeutics will come continued challenges for drug-development scientists, oncologists, and regulatory agencies in ensuring that patients achieve safe and efficacious exposures of their cancer therapeutics and thus optimal patient outcomes.

Adherence to drug-drug interaction alerts in high-risk patients: a trial of context-enhanced alerting.

PubMed

Duke, Jon D; Li, Xiaochun; Dexter, Paul

2013-05-01

Drug-drug interaction (DDI) alerting is an important form of clinical decision support, yet physicians often fail to attend to critical DDI warnings due to alert fatigue. We previously described a model for highlighting patients at high risk of a DDI by enhancing alerts with relevant laboratory data. We sought to evaluate the effect of this model on alert adherence in high-risk patients. A 6-month randomized controlled trial involving 1029 outpatient physicians was performed. The target interactions were all DDIs known to cause hyperkalemia. Alerts in the intervention group were enhanced with the patient's most recent potassium and creatinine levels. The control group received unmodified alerts. High -risk patients were those with baseline potassium >5.0 mEq/l and/or creatinine ≥1.5 mg/dl (132 μmol/l). We found no significant difference in alert adherence in high-risk patients between the intervention group (15.3%) and the control group (16.8%) (p=0.71). Adherence in normal risk patients was significantly lower in the intervention group (14.6%) than in the control group (18.6%) (p<0.01). In neither group did physicians increase adherence in patients at high risk. Physicians adhere poorly to hyperkalemia-associated DDI alerts even in patients with risk factors for a clinically significant interaction, and the display of relevant laboratory data in these alerts did not improve adherence levels in the outpatient setting. Further research is necessary to determine optimal strategies for conveying patient-specific DDI risk.

A survey of attitudes, practices, and knowledge regarding drug-drug interactions among medical residents in Iran.

PubMed

Nabovati, Ehsan; Vakili-Arki, Hasan; Taherzadeh, Zhila; Saberi, Mohammad Reza; Abu-Hanna, Ameen; Eslami, Saeid

2017-06-01

Background When prescribing medications, physicians should recognize clinically relevant potential drug-drug interactions (DDIs). To improve medication safety, it is important to understand prescribers' knowledge and opinions pertaining to DDIs. Objective To determine the current DDI information sources used by medical residents, their knowledge of DDIs, their opinions about performance feedback on co-prescription of interacting drugs. Setting Academic hospitals of Mashhad University of Medical Sciences (MUMS) in Iran. Methods A questionnaire containing questions regarding demographic and practice characteristics, DDI information sources, ability to recognize DDIs, and opinions about performance feedback was distributed to medical residents of 22 specialties in eight academic hospitals in Iran. We analyzed their perception pertaining to DDIs, their performance on classifying drug pairs, and we used a linear regression model to assess the association of potential determinants on their DDI knowledge. Main Outcome Measure prescribers' knowledge and opinions pertaining to DDIs. Results The overall response rate and completion rate for 315 distributed questionnaires were 90% (n = 295) and 86% (n = 281), respectively. Among DDI information sources, books, software on mobile phone or tablet, and Internet were the most commonly-used references. Residents could correctly classify only 41% (5.7/14) of the drug pairs. The regression model showed no significant association between residents' characteristics and their DDI knowledge. An overwhelming majority of the respondents (n = 268, 95.4%) wished to receive performance feedback on co-prescription of interacting drugs in their prescriptions. They mostly selected information technology-based tools (i.e. short text message and email) as their preferred method of receiving feedback. Conclusion Our findings indicate that prescribers may have poor ability to prevent clinically relevant potential DDI occurrence, and they perceive the need for performance feedback. These findings underline the importance of well-designed computerized alerting systems and delivering performance feedback to improve patient safety.

Factors influencing alert acceptance: a novel approach for predicting the success of clinical decision support

PubMed Central

Seidling, Hanna M; Phansalkar, Shobha; Seger, Diane L; Paterno, Marilyn D; Shaykevich, Shimon; Haefeli, Walter E

2011-01-01

Background Clinical decision support systems can prevent knowledge-based prescription errors and improve patient outcomes. The clinical effectiveness of these systems, however, is substantially limited by poor user acceptance of presented warnings. To enhance alert acceptance it may be useful to quantify the impact of potential modulators of acceptance. Methods We built a logistic regression model to predict alert acceptance of drug–drug interaction (DDI) alerts in three different settings. Ten variables from the clinical and human factors literature were evaluated as potential modulators of provider alert acceptance. ORs were calculated for the impact of knowledge quality, alert display, textual information, prioritization, setting, patient age, dose-dependent toxicity, alert frequency, alert level, and required acknowledgment on acceptance of the DDI alert. Results 50 788 DDI alerts were analyzed. Providers accepted only 1.4% of non-interruptive alerts. For interruptive alerts, user acceptance positively correlated with frequency of the alert (OR 1.30, 95% CI 1.23 to 1.38), quality of display (4.75, 3.87 to 5.84), and alert level (1.74, 1.63 to 1.86). Alert acceptance was higher in inpatients (2.63, 2.32 to 2.97) and for drugs with dose-dependent toxicity (1.13, 1.07 to 1.21). The textual information influenced the mode of reaction and providers were more likely to modify the prescription if the message contained detailed advice on how to manage the DDI. Conclusion We evaluated potential modulators of alert acceptance by assessing content and human factors issues, and quantified the impact of a number of specific factors which influence alert acceptance. This information may help improve clinical decision support systems design. PMID:21571746

Surveillance of Physicians Causing Potential Drug-Drug Interactions in Ambulatory Care: A Pilot Study in Switzerland

PubMed Central

Bucher, Heiner C.; Achermann, Rita; Stohler, Nadja; Meier, Christoph R.

2016-01-01

Objectives We analysed potential drug-drug interactions (DDI) in ambulatory care in Switzerland based on claims data from three large health insurers in 2010 to identify physicians with peculiar prescription behaviour differing from peers of the same specialty. Methods We analysed contraindicated or potentially contraindicated DDI from the national drug formulary and calculated for each physician the ratios of the number of patients with a potential DDI divided by the number of patients at risk and used a zero inflated binomial distribution to correct for the inflated number of observations with no DDI. We then calculated the probability that the number of caused potential DDI of physicians was unlikely (p-value < 0.05 and ≥0.01) and very unlikely (p-value <0.01) to be due to chance. Results Of 1'607'233 females and 1'525'307 males 1.3% and 1.2% were exposed to at least one potential DDI during 12 months. When analysing the 40 most common DDI, 598 and 416 of 18,297 physicians (3.3% and 2.3%) were causing potential DDI in a frequency unlikely (p<0.05 and p≥0.01) and very unlikely (p<0.01) to be explained by chance. Patients cared by general practitioners and cardiologists had the lowest probability (0.20 and 0.26) for not being exposed to DDI. Conclusions Contraindicated or potentially contraindicated DDI are frequent in ambulatory care in Switzerland, with a small proportion of physicians causing potential DDI in a frequency that is very unlikely to be explained by chance when compared to peers of the same specialty. PMID:26808430

Species-related exposure of phase II metabolite gemfibrozil 1-O-β-glucuronide between human and mice: A net induction of mouse P450 activity was revealed.

PubMed

Luo, Min; Dai, Manyun; Lin, Hante; Xie, Minzhu; Lin, Jiao; Liu, Aiming; Yang, Julin

2017-12-01

Gemfibrozil is a fibrate drug used widely for dyslipidemia associated with atherosclerosis. Clinically, both gemfibrozil and its phase II metabolite gemfibrozil 1-O-β-glucuronide (gem-glu) are involved in drug-drug interaction (DDI). But the DDI risk caused by gem-glu between human and mice has not been compared. In this study, six volunteers were recruited and took a therapeutic dose of gemfibrozil for 3 days for examination of the gemfibrozil and gem-glu level in human. Male mice were fed a gemfibrozil diet (0.75%) for 7 days, following which a cocktail-based inhibitory DDI experiment was performed. Plasma samples and liver tissues from mice were collected for determination of gemfibrozil, gem-glu concentration and cytochrome p450 enzyme (P450) induction analysis. In human, the molar ratio of gem-glu/gemfibrozil was 15% and 10% at the trough concentration and the concentration at 1.5 h after the 6th dose. In contrast, this molar ratio at steady state in mice was 91%, demonstrating a 6- to 9-fold difference compared with that in human. Interestingly, a net induction of P450 activity and in vivo inductive DDI potential in mice was revealed. The P450 activity was not inhibited although the gem-glu concentration was high. These data suggested species difference of relative gem-glu exposure between human and mice, as well as a net inductive DDI potential of gemfibrozil in mouse model. Copyright © 2017 John Wiley & Sons, Ltd.

Virtual Clinical Trial Toward Polytherapy Safety Assessment: Combination of Physiologically Based Pharmacokinetic/Pharmacodynamic-Based Modeling and Simulation Approach With Drug-Drug Interactions Involving Terfenadine as an Example.

PubMed

Wiśniowska, Barbara; Polak, Sebastian

2016-11-01

A Quantitative Systems Pharmacology approach was utilized to predict the cardiac consequences of drug-drug interaction (DDI) at the population level. The Simcyp in vitro-in vivo correlation and physiologically based pharmacokinetic platform was used to predict the pharmacokinetic profile of terfenadine following co-administration of the drug. Electrophysiological effects were simulated using the Cardiac Safety Simulator. The modulation of ion channel activity was dependent on the inhibitory potential of drugs on the main cardiac ion channels and a simulated free heart tissue concentration. ten Tusscher's human ventricular cardiomyocyte model was used to simulate the pseudo-ECG traces and further predict the pharmacodynamic consequences of DDI. Consistent with clinical observations, predicted plasma concentration profiles of terfenadine show considerable intra-subject variability with recorded C max values below 5 ng/mL for most virtual subjects. The pharmacokinetic and pharmacodynamic effects of inhibitors were predicted with reasonable accuracy. In all cases, a combination of the physiologically based pharmacokinetic and physiology-based pharmacodynamic models was able to differentiate between the terfenadine alone and terfenadine + inhibitor scenario. The range of QT prolongation was comparable in the clinical and virtual studies. The results indicate that mechanistic in vitro-in vivo correlation can be applied to predict the clinical effects of DDI even without comprehensive knowledge on all mechanisms contributing to the interaction. Copyright © 2016 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

A quantitative systems pharmacology approach, incorporating a novel liver model, for predicting pharmacokinetic drug-drug interactions.

PubMed

Cherkaoui-Rbati, Mohammed H; Paine, Stuart W; Littlewood, Peter; Rauch, Cyril

2017-01-01

All pharmaceutical companies are required to assess pharmacokinetic drug-drug interactions (DDIs) of new chemical entities (NCEs) and mathematical prediction helps to select the best NCE candidate with regard to adverse effects resulting from a DDI before any costly clinical studies. Most current models assume that the liver is a homogeneous organ where the majority of the metabolism occurs. However, the circulatory system of the liver has a complex hierarchical geometry which distributes xenobiotics throughout the organ. Nevertheless, the lobule (liver unit), located at the end of each branch, is composed of many sinusoids where the blood flow can vary and therefore creates heterogeneity (e.g. drug concentration, enzyme level). A liver model was constructed by describing the geometry of a lobule, where the blood velocity increases toward the central vein, and by modeling the exchange mechanisms between the blood and hepatocytes. Moreover, the three major DDI mechanisms of metabolic enzymes; competitive inhibition, mechanism based inhibition and induction, were accounted for with an undefined number of drugs and/or enzymes. The liver model was incorporated into a physiological-based pharmacokinetic (PBPK) model and simulations produced, that in turn were compared to ten clinical results. The liver model generated a hierarchy of 5 sinusoidal levels and estimated a blood volume of 283 mL and a cell density of 193 × 106 cells/g in the liver. The overall PBPK model predicted the pharmacokinetics of midazolam and the magnitude of the clinical DDI with perpetrator drug(s) including spatial and temporal enzyme levels changes. The model presented herein may reduce costs and the use of laboratory animals and give the opportunity to explore different clinical scenarios, which reduce the risk of adverse events, prior to costly human clinical studies.

Stringent DDI-based prediction of H. sapiens-M. tuberculosis H37Rv protein-protein interactions.

PubMed

Zhou, Hufeng; Rezaei, Javad; Hugo, Willy; Gao, Shangzhi; Jin, Jingjing; Fan, Mengyuan; Yong, Chern-Han; Wozniak, Michal; Wong, Limsoon

2013-01-01

H. sapiens-M. tuberculosis H37Rv protein-protein interaction (PPI) data are very important information to illuminate the infection mechanism of M. tuberculosis H37Rv. But current H. sapiens-M. tuberculosis H37Rv PPI data are very scarce. This seriously limits the study of the interaction between this important pathogen and its host H. sapiens. Computational prediction of H. sapiens-M. tuberculosis H37Rv PPIs is an important strategy to fill in the gap. Domain-domain interaction (DDI) based prediction is one of the frequently used computational approaches in predicting both intra-species and inter-species PPIs. However, the performance of DDI-based host-pathogen PPI prediction has been rather limited. We develop a stringent DDI-based prediction approach with emphasis on (i) differences between the specific domain sequences on annotated regions of proteins under the same domain ID and (ii) calculation of the interaction strength of predicted PPIs based on the interacting residues in their interaction interfaces. We compare our stringent DDI-based approach to a conventional DDI-based approach for predicting PPIs based on gold standard intra-species PPIs and coherent informative Gene Ontology terms assessment. The assessment results show that our stringent DDI-based approach achieves much better performance in predicting PPIs than the conventional approach. Using our stringent DDI-based approach, we have predicted a small set of reliable H. sapiens-M. tuberculosis H37Rv PPIs which could be very useful for a variety of related studies. We also analyze the H. sapiens-M. tuberculosis H37Rv PPIs predicted by our stringent DDI-based approach using cellular compartment distribution analysis, functional category enrichment analysis and pathway enrichment analysis. The analyses support the validity of our prediction result. Also, based on an analysis of the H. sapiens-M. tuberculosis H37Rv PPI network predicted by our stringent DDI-based approach, we have discovered some important properties of domains involved in host-pathogen PPIs. We find that both host and pathogen proteins involved in host-pathogen PPIs tend to have more domains than proteins involved in intra-species PPIs, and these domains have more interaction partners than domains on proteins involved in intra-species PPI. The stringent DDI-based prediction approach reported in this work provides a stringent strategy for predicting host-pathogen PPIs. It also performs better than a conventional DDI-based approach in predicting PPIs. We have predicted a small set of accurate H. sapiens-M. tuberculosis H37Rv PPIs which could be very useful for a variety of related studies.

In vitro and physiologically‐based pharmacokinetic based assessment of drug–drug interaction potential of canagliflozin

PubMed Central

Dallas, Shannon; Sensenhauser, Carlo; Lim, Heng Keang; Scheers, Ellen; Verboven, Peter; Cuyckens, Filip; Leclercq, Laurent; Evans, David C.; Kelley, Michael F.; Johnson, Mark D.; Snoeys, Jan

2016-01-01

Aims Canagliflozin is a recently approved drug for use in the treatment of type 2 diabetes. The potential for canagliflozin to cause clinical drug–drug interactions (DDIs) was assessed. Methods DDI potential of canagliflozin was investigated using in vitro test systems containing drug metabolizing enzymes or transporters. Basic predictive approaches were applied to determine potential interactions in vivo. A physiologically‐based pharmacokinetic (PBPK) model was developed and clinical DDI simulations were performed to determine the likelihood of cytochrome P450 (CYP) inhibition by canagliflozin. Results Canagliflozin was primarily metabolized by uridine 5′‐diphospho‐glucuronosyltransferase 1A9 and 2B4 enzymes. Canagliflozin was a substrate of efflux transporters (P‐glycoprotein, breast cancer resistance protein and multidrug resistance‐associated protein‐2) but was not a substrate of uptake transporters (organic anion transporter polypeptide isoforms OATP1B1, OATP1B3, organic anion transporters OAT1 and OAT3, and organic cationic transporters OCT1, and OCT2). In inhibition assays, canagliflozin was shown to be a weak in vitro inhibitor (IC50) of CYP3A4 (27 μmol l –1, standard error [SE] 4.9), CYP2C9 (80 μmol l –1, SE 8.1), CYP2B6 (16 μmol l–1, SE 2.1), CYP2C8 (75 μmol l –1, SE 6.4), P‐glycoprotein (19.3 μmol l –1, SE 7.2), and multidrug resistance‐associated protein‐2 (21.5 μmol l –1, SE 3.1). Basic models recommended in DDI guidelines (US Food & Drug Administration and European Medicines Agency) predicted moderate to low likelihood of interaction for these CYPs and efflux transporters. PBPK DDI simulations of canagliflozin with CYP probe substrates (simvastatin, S‐warfarin, bupropion, repaglinide) did not show relevant interaction in humans since mean areas under the concentration‐time curve and maximum plasma concentration ratios for probe substrates with and without canagliflozin and its 95% CIs were within 0.80–1.25. Conclusions In vitro DDI followed by a predictive or PBPK approach was applied to determine DDI potential of canagliflozin. Overall, canagliflozin is neither a perpetrator nor a victim of clinically important interactions. PMID:27862160

Predicting the effect of cytochrome P450 inhibitors on substrate drugs: analysis of physiologically based pharmacokinetic modeling submissions to the US Food and Drug Administration.

PubMed

Wagner, Christian; Pan, Yuzhuo; Hsu, Vicky; Grillo, Joseph A; Zhang, Lei; Reynolds, Kellie S; Sinha, Vikram; Zhao, Ping

2015-01-01

The US Food and Drug Administration (FDA) has seen a recent increase in the application of physiologically based pharmacokinetic (PBPK) modeling towards assessing the potential of drug-drug interactions (DDI) in clinically relevant scenarios. To continue our assessment of such approaches, we evaluated the predictive performance of PBPK modeling in predicting cytochrome P450 (CYP)-mediated DDI. This evaluation was based on 15 substrate PBPK models submitted by nine sponsors between 2009 and 2013. For these 15 models, a total of 26 DDI studies (cases) with various CYP inhibitors were available. Sponsors developed the PBPK models, reportedly without considering clinical DDI data. Inhibitor models were either developed by sponsors or provided by PBPK software developers and applied with minimal or no modification. The metric for assessing predictive performance of the sponsors' PBPK approach was the R predicted/observed value (R predicted/observed = [predicted mean exposure ratio]/[observed mean exposure ratio], with the exposure ratio defined as [C max (maximum plasma concentration) or AUC (area under the plasma concentration-time curve) in the presence of CYP inhibition]/[C max or AUC in the absence of CYP inhibition]). In 81 % (21/26) and 77 % (20/26) of cases, respectively, the R predicted/observed values for AUC and C max ratios were within a pre-defined threshold of 1.25-fold of the observed data. For all cases, the R predicted/observed values for AUC and C max were within a 2-fold range. These results suggest that, based on the submissions to the FDA to date, there is a high degree of concordance between PBPK-predicted and observed effects of CYP inhibition, especially CYP3A-based, on the exposure of drug substrates.

DNA-damage-inducible 1 protein (Ddi1) contains an uncharacteristic ubiquitin-like domain that binds ubiquitin

PubMed Central

Nowicka, Urszula; Zhang, Daoning; Walker, Olivier; Krutauz, Daria; Castañeda, Carlos A.; Chaturvedi, Apurva; Chen, Tony Y.; Reis, Noa; Glickman, Michael H.; Fushman, David

2015-01-01

SUMMARY Ddi1 belongs to a family of shuttle proteins targeting polyubiquitinated substrates for proteasomal degradation. Unlike the other proteasomal shuttles, Rad23 and Dsk2, Ddi1 remains an enigma: its function is not fully understood and structural properties are poorly characterized. We determined the structure and binding properties of the ubiquitin-like (UBL) and ubiquitin-associated (UBA) domains of Ddi1 from Saccharomyces cerevisiae. We found that, while Ddi1UBA forms a characteristic UBA:ubiquitin complex, Ddi1UBL has entirely uncharacteristic binding preferences. Despite having a ubiquitin-like fold, Ddi1UBL does not interact with typical UBL-receptors but, unexpectedly, binds ubiquitin, forming a unique interface mediated by hydrophobic contacts and by salt-bridges between oppositely-charged residues of Ddi1UBL and ubiquitin. In stark contrast with ubiquitin and other UBLs, the β-sheet surface of Ddi1UBL is negatively charged and, therefore, is recognized in a completely different way. The dual functionality of Ddi1UBL, capable of binding both ubiquitin and proteasome, suggests a novel mechanism for Ddi1 as a proteasomal shuttle. PMID:25703377

E-learning in order to improve drug prescription for hospitalized older patients: a cluster-randomized controlled study.

PubMed

Franchi, Carlotta; Tettamanti, Mauro; Djade, Codjo Dgnefa; Pasina, Luca; Mannucci, Pier Mannuccio; Onder, Graziano; Gussoni, Gualberto; Manfellotto, Dario; Bonassi, Stefano; Salerno, Francesco; Nobili, Alessandro

2016-07-01

The aim of the study was to evaluate the effect of an e-learning educational program meant to foster the quality of drug prescription in hospitalized elderly patients. Twenty geriatric and internal medicine wards were randomized to intervention (e-learning educational program) or control (basic geriatric pharmacology notions). Logistic regression analysis was used in order to assess the effect of the intervention on the use of potentially inappropriate medication (PIM, primary outcome) at hospital discharge. Secondary outcomes were a reduced prevalence of at least one potential drug-drug interaction (DDI) and potentially severe DDI at discharge. Mortality rate and incidence of re-hospitalizations were other secondary outcomes assessed at the 12-month follow-up. A total of 697 patients (347 in the intervention and 350 in the control arms) were enrolled. No difference in the prevalence of PIM at discharge was found between arms (OR 1.29 95%CI 0.87-1.91). We also found no decrease in the prevalence of DDI (OR 0.67 95%CI 0.34-1.28) and potentially severe DDI (OR 0.86 95%CI 0.63-1.15) at discharge, nor in mortality rates and incidence of re-hospitalization at 12-month follow-up. This e-learning educational program had no clear effect on the quality of drug prescription and clinical outcomes in hospitalized elderly patients. Given the high prevalence of PIMs and potential DDIs recorded in the frame of this study, other approaches should be developed in order to improve the quality of drug prescription in this population. © 2016 The British Pharmacological Society.

Transfer of Ho Endonuclease and Ufo1 to the Proteasome by the UbL-UbA Shuttle Protein, Ddi1, Analysed by Complex Formation In Vitro

PubMed Central

Voloshin, Olga; Bakhrat, Anya; Herrmann, Sharon; Raveh, Dina

2012-01-01

The F-box protein, Ufo1, recruits Ho endonuclease to the SCFUfo1 complex for ubiquitylation. Both ubiquitylated Ho and Ufo1 are transferred by the UbL-UbA protein, Ddi1, to the 19S Regulatory Particle (RP) of the proteasome for degradation. The Ddi1-UbL domain binds Rpn1 of the 19S RP, the Ddi1-UbA domain binds ubiquitin chains on the degradation substrate. Here we used complex reconstitution in vitro to identify stages in the transfer of Ho and Ufo1 from the SCFUfo1 complex to the proteasome. We report SCFUfo1 complex at the proteasome formed in the presence of Ho. Subsequently Ddi1 is recruited to this complex by interaction between the Ddi1-UbL domain and Ufo1. The core of Ddi1 binds both Ufo1 and Rpn1; this interaction confers specificity of SCFUfo1 for Ddi1. The substrate-shield model predicts that Ho would protect Ufo1 from degradation and we find that Ddi1 binds Ho, Ufo1, and Rpn1 simultaneously forming a complex for transfer of Ho to the 19S RP. In contrast, in the absence of Ho, Rpn1 displaces Ufo1 from Ddi1 indicating a higher affinity of the Ddi1-UbL for the 19S RP. However, at high Rpn1 levels there is synergistic binding of Ufo1 to Ddi1 that is dependent on the Ddi1-UbA domain. Our interpretation is that in the absence of substrate, the Ddi1-UbL binds Rpn1 while the Ddi1-UbA binds ubiquitin chains on Ufo1. This would promote degradation of Ufo1 and disassembly of SCFUfo1 complexes. PMID:22815701

The tomato DWD motif-containing protein DDI1 interacts with the CUL4–DDB1-based ubiquitin ligase and plays a pivotal role in abiotic stress responses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miao, Min; School of Biotechnology and Food Engineering, Hefei University of Technology, Hefei 230009; Department of Plant, Soil and Entomological Sciences, University of Idaho, Moscow, ID 83844-2339

2014-08-08

Highlights: • We identify DDI1 as a DAMAGED DNA BINDING PROTEIN1 (DDB1)-interacting protein. • DDI1 interacts with the CUL4–DDB1-based ubiquitin ligase in the nucleus. • DDI1 plays a positive role in regulating abiotic stress response in tomato. - Abstract: CULLIN4(CUL4)–DAMAGED DNA BINDING PROTEIN1 (DDB1)-based ubiquitin ligase plays significant roles in multiple physiological processes via ubiquitination-mediated degradation of relevant target proteins. The DDB1–CUL4-associated factor (DCAF) acts as substrate receptor in the CUL4–DDB1 ubiquitin ligase complex and determines substrate specificity. In this study, we identified a tomato (Solanum lycopersicum) DDB1-interacting (DDI1) protein as a DCAF protein involved in response to abiotic stresses,more » including UV radiation, high salinity and osmotic stress. Co-immunoprecipitation and bimolecular fluorescence complementation assay indicated that DDI1 associates with CUL4–DDB1 in the nucleus. Quantitative RT-PCR analysis indicated the DDI1 gene is induced by salt, mannitol and UV-C treatment. Moreover, transgenic tomato plants with overexpression or knockdown of the DDI1 gene exhibited enhanced or attenuated tolerance to salt/mannitol/UV-C, respectively. Thus, our data suggest that DDI1 functions as a substrate receptor of the CUL4–DDB1 ubiquitin ligase, positively regulating abiotic stress response in tomato.« less

Stringent DDI-based Prediction of H. sapiens-M. tuberculosis H37Rv Protein-Protein Interactions

PubMed Central

2013-01-01

Background H. sapiens-M. tuberculosis H37Rv protein-protein interaction (PPI) data are very important information to illuminate the infection mechanism of M. tuberculosis H37Rv. But current H. sapiens-M. tuberculosis H37Rv PPI data are very scarce. This seriously limits the study of the interaction between this important pathogen and its host H. sapiens. Computational prediction of H. sapiens-M. tuberculosis H37Rv PPIs is an important strategy to fill in the gap. Domain-domain interaction (DDI) based prediction is one of the frequently used computational approaches in predicting both intra-species and inter-species PPIs. However, the performance of DDI-based host-pathogen PPI prediction has been rather limited. Results We develop a stringent DDI-based prediction approach with emphasis on (i) differences between the specific domain sequences on annotated regions of proteins under the same domain ID and (ii) calculation of the interaction strength of predicted PPIs based on the interacting residues in their interaction interfaces. We compare our stringent DDI-based approach to a conventional DDI-based approach for predicting PPIs based on gold standard intra-species PPIs and coherent informative Gene Ontology terms assessment. The assessment results show that our stringent DDI-based approach achieves much better performance in predicting PPIs than the conventional approach. Using our stringent DDI-based approach, we have predicted a small set of reliable H. sapiens-M. tuberculosis H37Rv PPIs which could be very useful for a variety of related studies. We also analyze the H. sapiens-M. tuberculosis H37Rv PPIs predicted by our stringent DDI-based approach using cellular compartment distribution analysis, functional category enrichment analysis and pathway enrichment analysis. The analyses support the validity of our prediction result. Also, based on an analysis of the H. sapiens-M. tuberculosis H37Rv PPI network predicted by our stringent DDI-based approach, we have discovered some important properties of domains involved in host-pathogen PPIs. We find that both host and pathogen proteins involved in host-pathogen PPIs tend to have more domains than proteins involved in intra-species PPIs, and these domains have more interaction partners than domains on proteins involved in intra-species PPI. Conclusions The stringent DDI-based prediction approach reported in this work provides a stringent strategy for predicting host-pathogen PPIs. It also performs better than a conventional DDI-based approach in predicting PPIs. We have predicted a small set of accurate H. sapiens-M. tuberculosis H37Rv PPIs which could be very useful for a variety of related studies. PMID:24564941

[Effect of the economic crisis on consumption of psychotropic drugs in Asturias (Spain)].

PubMed

Nicieza-García, María Luisa; Alonso-Lorenzo, Julio C; Suárez-Gil, Patricio; Rilla-Villar, Natalia

To assess whether the economic crisis of 2008 has changed the consumption of anxiolytics, hypnotics-sedatives and antidepressants in Asturias (Spain). We conducted a descriptive study of drug use from 2003 -2013. The defined daily doses of 1000 inhabitants per day (DHD) were calculated for anxiolytics, hypnotics-sedatives and antidepressants. Linear regression coefficients (b) of the DHD were obtained for the pre-crisis period (2003-2008) and the crisis period (2009-2013). The consumption of anxiolytics increased by 40.25%, that of hypnotics by 88.11% and that of antidepressants by 80.93%. For anxiolytics: b-(2003-2008)=4.38 DDI/year and b-(2009-2013)=1.08 DDI/year. For hypnotics-sedatives: b-(2003-2008)=2.30 DDI/year and b-(2009-2013)=0.40 DDI/year. For antidepressants: b-(2003-2008)=5.79 DDI/year and b-(2009-2013)=2.83 DDI/year. The rise in consumption of the three subgroups during the crisis period was lower than that of the pre-crisis period. This study does not confirm the influence of the economic crisis on the rise in consumption of these drugs. Copyright © 2016 SESPAS. Publicado por Elsevier España, S.L.U. All rights reserved.

Medication Use and Medical Comorbidity in Patients with Chronic Hepatitis C from a U.S. Commercial Claims Database: High Utilization of Drugs with Interaction Potential

PubMed Central

Lauffenburger, Julie C.; Mayer, Christina L.; Hawke, Roy L.; Brouwer, Kim L. R.; Fried, Michael W.; Farley, Joel F.

2014-01-01

Background With the advent of the direct-acting antiviral agents (DAAs), significant drug-drug interaction (DDI) potential now exists for patients treated for chronic hepatitis C virus (HCV) infection. However, little is known about how often patients with HCV use medications that may interact with newer HCV treatments, especially those with CYP3A DDI potential. Methods Using a large United States commercial insurance database, medication use and comorbidity burden was examined among adult patients with a chronic HCV diagnosis from 2006-2010. Medications were examined by total number of prescription claims, proportion of patients exposed, and DDI potential with prototypical CYP3A DAAs, boceprevir and telaprevir, for which data were available. Results Patient comorbidity burden was high and increased over the study period. Medication use was investigated in 53,461 patients with chronic HCV. Twenty-one (53%) of the top 40 most utilized medications were classified as having interaction potential, with 62% of patients received at least one of the top 22 interacting medications by exposure. Of these, 59% and 41% were listed in a common DDI resource but not in medication prescribing information, 77% and 77% had not been investigated in DDI studies, 32% and 27% did not have clear recommendations for DDI management, and only 14% and 23% carried a recommendation to avoid coadministration for boceprevir and telaprevir, respectively. Conclusion Practitioners may expect a medication with CYP3A DDI potential in two-thirds of patients with HCV and almost one-half of the most frequently used medications. However, DDI potential may not be reflected in prescribing information. PMID:25014625

The decision to delivery interval in emergency caesarean sections: Impact of anaesthetic technique and work shift.

PubMed

Hein, Anette; Thalen, David; Eriksson, Ylva; Jakobsson, Jan G

2017-01-01

Background: One important task of the emergency anaesthesia service is to provide rapid, safe and effective anaesthesia for emergency caesarean sections (ECS). A Decision to Delivery Interval (DDI) <30 minutes for ECS is a quality indicator for this service. The aim of this study was to assess the DDI and the impact of chosen anaesthetic technique (general anaesthesia (GA), spinal anaesthesia (SPA) with opioid supplementation, or "top-up" of labour epidural analgesia (tEDA) with local anaesthesia and fentanyl mixture) and work shift for ECS at Danderyds Hospital, Sweden. Methods: A retrospective chart review of ECS at Danderyds Hospital was performed between January and October 2016. Time between decision for CS, start of anaesthesia, time for incision and delivery, type of anaesthetic technique, and time of day, working hours or on call and day of week, Monday - Friday, and weekend was compiled and analysed. Time events are presented as mean ± standard deviation. Non-parametric tests were used. Results: In total, 135 ECS were analysed: 92% of the cases were delivered within 30 minutes and mean DDI for all cases was 17.3±8.1 minutes. GA shortened the DDI by 10 and 13 minutes compared to SPA and tEDA (p<0.0005). DDI for SPA and tEDA did not differ. There was no difference in DDI regarding time of day or weekday. Apgar <7 at 5' was more commonly seen in ECS having GA (11 out of 64) compared to SPA (2/30) and tEDA (1/41) (p<0.05). Conclusion: GA shortens the DDI for ECS, but the use of SPA as well as tEDA with opioid supplementation maintains a short DDI and should be considered when time allows. Top-up epidural did not prolong the DDI compared to SPA. The day of week or time of ECS had no influence on the anaesthesia service as measured by the DDI.

An Investigation of Drug-Drug Interaction Alert Overrides at a Pediatric Hospital.

PubMed

Humphrey, Kate; Jorina, Maria; Harper, Marvin; Dodson, Brenda; Kim, Seung-Yeon; Ozonoff, Al

2018-05-01

Drug-drug interactions (DDIs) can result in patient harm. DDI alerts are intended to help prevent harm; when the majority of alerts presented to providers are being overridden, their value is diminished. Our objective was to evaluate the overall rates of DDI alert overrides and how rates varied by specialty, clinician type, and patient complexity. A retrospective study of DDI alert overrides that occurred during 2012 and 2013 within the inpatient setting described at the medication-, hospital-, provider-, and patient encounter-specific levels was performed at an urban, quaternary-care, pediatric hospital. There were >41 000 DDI alerts presented to clinicians; ∼90% were overridden. The 5 DDI pairs that were most frequently presented and overridden included the following: potassium chloride-spironolactone, methadone-ondansetron, ketorolac-ibuprofen, cyclosporine-fluconazole, and potassium chloride-enalapril, each with an alert override rate of ≥0.89. Override rates across provider groups ranged between 0.84 and 0.97. In general, patients with high complexity had a higher frequency of alert overrides, but the rates of alert overrides for each DDI pairing did not differ significantly. High rates of DDI alert overrides occur across medications, provider groups, and patient encounters. Methods to decrease DDI alerts which are likely to be overridden exist, but it is also clear that more robust and intelligent tools are needed. Characteristics exist at the medication, hospital, provider, and patient levels that can be used to help specialize and enhance information transmission. Copyright © 2018 by the American Academy of Pediatrics.

Consistency of psychotropic drug-drug interactions listed in drug monographs.

PubMed

Liu, Xinyue; Hatton, Randy C; Zhu, Yanmin; Hincapie-Castillo, Juan M; Bussing, Regina; Barnicoat, Marie; Winterstein, Almut G

With an increasing prevalence of psychotropic polypharmacy, clinicians depend on drug-drug interaction (DDI) references to ensure safe regimens, but the consistency of such information is frequently questioned. To evaluate the consistency of psychotropic DDIs documented in Clinical Pharmacology (CP), Micromedex (MM), and Lexicomp (LC) and summarize consistent psychotropic DDIs. In May 2016, we extracted severe or major psychotropic DDIs for 102 psychotropic drugs, including central nervous system (CNS) stimulants, antidepressants, an antimanic agent (lithium), antipsychotics, anticonvulsants, and anxiolytics-sedatives-hypnotics from CP, MM, and LC. We then summarized the psychotropic DDIs that were included in all 3 references and with evidence quality of "excellent" or "good" based on MM. We identified 1496, 938, and 1006 unique severe or major psychotropic DDIs from CP, MM, and LC, respectively. Common adverse effects related to psychotropic DDIs include increased or decreased effectiveness, CNS depression, neurotoxicity, QT prolongation, serotonin syndrome, and multiple adverse effects. Among these interactions, only 371 psychotropic DDIs were documented in all 3 references, 59 of which had "excellent" or "good" quality of evidence based on MM. The consistency of psychotropic DDI documentation across CP, MM, and LC is poor. DDI documentations need standards that would encourage consistency among drug information references. The list of the 59 DDIs may be useful in the assessment of psychotropic polypharmacy and highlighting DDI alerts in clinical practice. Copyright © 2017 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

Periodontal status of patients with dentin dysplasia type I: report of three cases within a family.

PubMed

Da Rós Gonçalves, Lorena; Oliveira, Cristiana Aroeira G R; Holanda, Rose; Silva-Boghossian, Carina M; Colombo, Ana Paula Vieira; Maia, Lucianne Cople; Feres-Filho, Eduardo Jorge

2008-07-01

Dentin dysplasia type I (DDI) is a rare hereditary disturbance of dentin formation. It is characterized by clinically normal-appearing crowns; obliteration of pulp chambers; and short, blunted and malformed roots that are commonly associated with periodontal attachment loss (PAL). In this context, we report three cases within a family with similar clinical and radiographic features of DDI but with differing microbiologic and periodontal conditions. A 42-year-old white female and her two daughters (25 and 10 years of age) presented with a diagnosis of DDI. Probing depth (PD), clinical attachment level (CAL), visible plaque, and bleeding on probing (BOP) were recorded. Subgingival biofilm samples were randomly collected and analyzed by checkerboard DNA-DNA hybridization. The mother presented 34.9% of sites with PD > or =4 mm, 41.3% of sites with CAL > or =4 mm, and 57% of sites with BOP; both daughters presented no sites with PD or CAL >3 mm and <10% of sites with BOP. Microbiologic analysis detected Gemella morbillorum, Neisseria mucosa, and Staphylococcus aureus in > or =50% of the mother's samples. The daughters showed high levels (>10(4) bacterial cells) of some periodontopathic bacteria, including members of the red (Porphyromonas gingivalis) and orange (Fusobacterium periodonticum and F. nucleatum polymorphum) complexes and beneficial species of the yellow (Streptococcus gordonii) and purple (Veillonella parvula) complexes. The mother presented high mean levels only for four tested species (N. mucosa, Prevotella melaninogenica, Treponema denticola, and V. parvula). A combination of radiographs, microbiologic analysis, and preventive professional monitoring care is important to avoid PAL and to provide oral health in patients with DDI.

Phase I study of 2'-3'-dideoxyinosine administered orally twice daily to patients with AIDS or AIDS-related complex and hematologic intolerance to zidovudine.

PubMed

Connolly, K J; Allan, J D; Fitch, H; Jackson-Pope, L; McLaren, C; Canetta, R; Groopman, J E

1991-11-01

To evaluate the safety and hematologic tolerance of 2'-3'-dideoxyinosine (didanosine, ddI) in subjects with acquired immunodeficiency syndrome (AIDS) or AIDS-related complex and prior hematologic intolerance to zidovudine. A Phase I trial with two dose groups at a single-center, university-affiliated hospital ambulatory care center. Of 30 subjects enrolled, 21 had AIDS and nine had AIDS-related complex. All had CD4 lymphocyte counts less than 0.2 x 10(9)/L at entry. Didanosine was administered orally twice daily at a total daily dose of 750 mg or 1,500 mg for 12 weeks. Subjects who completed the 12-week study continued to receive ddI at the lower dose. All subjects were monitored for toxicity. Virologic and immunologic response markers were also measured. For the group as a whole, there was no significant decrease in mean hemoglobin level or leukocyte or platelet counts. The dose-limiting toxicity was peripheral neuropathy. Other significant toxicities included pancreatitis and hypocalcemia. Uric acid elevations were common but were without clinical consequence. A sustained decrease in serum p24 antigen of at least 50% was noted in 42% of subjects who were p24 antigen-positive at entry. The mean CD4 lymphocyte count showed an initial increase that was not sustained over the 12-week study. All subjects remained anergic to skin testing. Didanosine is well tolerated hematologically in some patients with prior significant hematologic intolerance to zidovudine. The toxicity profile for ddI differs from that of zidovudine and includes peripheral neuropathy and pancreatitis. Changes in CD4 lymphocyte number and HIV p24 antigen levels in some patients suggest antiviral activity of ddI in this population.

E‐learning in order to improve drug prescription for hospitalized older patients: a cluster‐randomized controlled study

PubMed Central

Tettamanti, Mauro; Djade, Codjo Dgnefa; Pasina, Luca; Mannucci, Pier Mannuccio; Onder, Graziano; Gussoni, Gualberto; Manfellotto, Dario; Bonassi, Stefano; Salerno, Francesco; Nobili, Alessandro

2016-01-01

Aims The aim of the study was to evaluate the effect of an e‐learning educational program meant to foster the quality of drug prescription in hospitalized elderly patients. Methods Twenty geriatric and internal medicine wards were randomized to intervention (e‐learning educational program) or control (basic geriatric pharmacology notions). Logistic regression analysis was used in order to assess the effect of the intervention on the use of potentially inappropriate medication (PIM, primary outcome) at hospital discharge. Secondary outcomes were a reduced prevalence of at least one potential drug–drug interaction (DDI) and potentially severe DDI at discharge. Mortality rate and incidence of re‐hospitalizations were other secondary outcomes assessed at the 12‐month follow‐up. Results A total of 697 patients (347 in the intervention and 350 in the control arms) were enrolled. No difference in the prevalence of PIM at discharge was found between arms (OR 1.29 95%CI 0.87–1.91). We also found no decrease in the prevalence of DDI (OR 0.67 95%CI 0.34–1.28) and potentially severe DDI (OR 0.86 95%CI 0.63–1.15) at discharge, nor in mortality rates and incidence of re‐hospitalization at 12‐month follow‐up. Conclusions This e‐learning educational program had no clear effect on the quality of drug prescription and clinical outcomes in hospitalized elderly patients. Given the high prevalence of PIMs and potential DDIs recorded in the frame of this study, other approaches should be developed in order to improve the quality of drug prescription in this population. PMID:26922904

Drug drug interaction extraction from the literature using a recursive neural network

PubMed Central

Lim, Sangrak; Lee, Kyubum

2018-01-01

Detecting drug-drug interactions (DDI) is important because information on DDIs can help prevent adverse effects from drug combinations. Since there are many new DDI-related papers published in the biomedical domain, manually extracting DDI information from the literature is a laborious task. However, text mining can be used to find DDIs in the biomedical literature. Among the recently developed neural networks, we use a Recursive Neural Network to improve the performance of DDI extraction. Our recursive neural network model uses a position feature, a subtree containment feature, and an ensemble method to improve the performance of DDI extraction. Compared with the state-of-the-art models, the DDI detection and type classifiers of our model performed 4.4% and 2.8% better, respectively, on the DDIExtraction Challenge’13 test data. We also validated our model on the PK DDI corpus that consists of two types of DDIs data: in vivo DDI and in vitro DDI. Compared with the existing model, our detection classifier performed 2.3% and 6.7% better on in vivo and in vitro data respectively. The results of our validation demonstrate that our model can automatically extract DDIs better than existing models. PMID:29373599

Dehydrogenation involved Coulomb explosion of molecular C2H4FBr in an intense laser field

NASA Astrophysics Data System (ADS)

Pei, Minjie; Yang, Yan; Zhang, Jian; Sun, Zhenrong

2018-04-01

The dissociative double ionization (DDI) of molecular 1-fluo-2-bromoethane (FBE) in an intense laser field has been investigated by dc-slice imaging technology. The DDI channels involved with dehydrogenation are revealed and it's believed both the charge distribution and the bound character of real potential energy surfaces of parent ions play important roles in the dissociation process. The relationship between the potential energy surfaces of the precursor species and the photofragment ejection angles are also discussed and analyzed. Furthermore, the competition between the DDI channels has been studied and the Csbnd C bond cleavages dominate the DDI process at relative higher laser intensity.

In Vitro Dissolution of Fluconazole and Dipyridamole in Gastrointestinal Simulator (GIS), Predicting in Vivo Dissolution and Drug-Drug Interaction Caused by Acid-Reducing Agents.

PubMed

Matsui, Kazuki; Tsume, Yasuhiro; Amidon, Gregory E; Amidon, Gordon L

2015-07-06

Weakly basic drugs typically exhibit pH-dependent solubility in the physiological pH range, displaying supersaturation or precipitation along the gastrointestinal tract. Additionally, their oral bioavailabilities may be affected by coadministration of acid-reducing agents that elevate gastric pH. The purpose of this study was to assess the feasibility of a multicompartmental in vitro dissolution apparatus, Gastrointestinal Simulator (GIS), in predicting in vivo dissolution of certain oral medications. In vitro dissolution studies of fluconazole, a BCS class I, and dipyridamole, a BCS class II weak bases (class IIb), were performed in the GIS as well as United States Pharmacopeia (USP) apparatus II and compared with the results of clinical drug-drug interaction (DDI) studies. In both USP apparatus II and GIS, fluconazole completely dissolved within 60 min regardless of pH, reflecting no DDI between fluconazole and acid-reducing agents in a clinical study. On the other hand, seven-fold and 15-fold higher concentrations of dipyridamole than saturation solubility were observed in the intestinal compartments in GIS with gastric pH 2.0. Precipitation of dipyridamole was also observed in the GIS, and the percentage of dipyridamole in solution was 45.2 ± 7.0%. In GIS with gastric pH 6.0, mimicking the coadministration of acid-reducing agents, the concentration of dipyridamole was equal to its saturation solubility, and the percentage of drug in solution was 9.3 ± 2.7%. These results are consistent with the clinical DDI study of dipyridamole with famotidine, which significantly reduced the Cmax and area under the curve. An In situ mouse infusion study combined with GIS revealed that high concentration of dipyridamole in the GIS enhanced oral drug absorption, which confirmed the supersaturation of dipyridamole. In conclusion, GIS was shown to be a useful apparatus to predict in vivo dissolution for BCS class IIb drugs.

Drug–drug interaction of microdose and regular-dose omeprazole with a CYP2C19 inhibitor and inducer

PubMed Central

Park, Gab-jin; Bae, Soo Hyeon; Park, Wan-Su; Han, Seunghoon; Park, Min-Ho; Shin, Seok-Ho; Shin, Young G; Yim, Dong-Seok

2017-01-01

Purpose A microdose drug–drug interaction (DDI) study may be a valuable tool for anticipating drug interaction at therapeutic doses. This study aimed to compare the magnitude of DDIs at microdoses and regular doses to explore the applicability of a microdose DDI study. Patients and methods Six healthy male volunteer subjects were enrolled into each DDI study of omeprazole (victim) and known perpetrators: fluconazole (inhibitor) and rifampin (inducer). For both studies, the microdose (100 μg, cold compound) and the regular dose (20 mg) of omeprazole were given at days 0 and 1, respectively. On days 2–9, the inhibitor or inducer was given daily, and the microdose and regular dose of omeprazole were repeated at days 8 and 9, respectively. Full omeprazole pharmacokinetic samplings were performed at days 0, 1, 8, and 9 of both studies for noncompartmental analysis. Results The magnitude of the DDI, the geometric mean ratios (with perpetrator/omeprazole only) of maximum concentration (Cmax) and area under the curve to the last measurement (AUCt) of the microdose and the regular dose were compared. The geometric mean ratios in the inhibition study were: 2.17 (micro) and 2.68 (regular) for Cmax, and 4.07 (micro), 4.33 (regular) for AUCt. For the induction study, they were 0.26 (micro) and 0.21 (regular) for Cmax, and 0.16 (micro) and 0.15 (regular) for AUCt. There were no significant statistical differences in the magnitudes of DDIs between microdose and regular-dose conditions, regardless of induction or inhibition. Conclusion Our results may be used as partial evidence that microdose DDI studies may replace regular-dose studies, or at least be used for DDI-screening purposes. PMID:28408803

Drug-drug interaction of microdose and regular-dose omeprazole with a CYP2C19 inhibitor and inducer.

PubMed

Park, Gab-Jin; Bae, Soo Hyeon; Park, Wan-Su; Han, Seunghoon; Park, Min-Ho; Shin, Seok-Ho; Shin, Young G; Yim, Dong-Seok

2017-01-01

A microdose drug-drug interaction (DDI) study may be a valuable tool for anticipating drug interaction at therapeutic doses. This study aimed to compare the magnitude of DDIs at microdoses and regular doses to explore the applicability of a microdose DDI study. Six healthy male volunteer subjects were enrolled into each DDI study of omeprazole (victim) and known perpetrators: fluconazole (inhibitor) and rifampin (inducer). For both studies, the microdose (100 μg, cold compound) and the regular dose (20 mg) of omeprazole were given at days 0 and 1, respectively. On days 2-9, the inhibitor or inducer was given daily, and the microdose and regular dose of omeprazole were repeated at days 8 and 9, respectively. Full omeprazole pharmacokinetic samplings were performed at days 0, 1, 8, and 9 of both studies for noncompartmental analysis. The magnitude of the DDI, the geometric mean ratios (with perpetrator/omeprazole only) of maximum concentration (C max ) and area under the curve to the last measurement (AUC t ) of the microdose and the regular dose were compared. The geometric mean ratios in the inhibition study were: 2.17 (micro) and 2.68 (regular) for C max , and 4.07 (micro), 4.33 (regular) for AUC t . For the induction study, they were 0.26 (micro) and 0.21 (regular) for C max , and 0.16 (micro) and 0.15 (regular) for AUC t . There were no significant statistical differences in the magnitudes of DDIs between microdose and regular-dose conditions, regardless of induction or inhibition. Our results may be used as partial evidence that microdose DDI studies may replace regular-dose studies, or at least be used for DDI-screening purposes.

77 FR 71211 - Request for Information: Establish a Public-Private Collaboration, “Drug Development Initiative...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-11-29

... clinical trials with the support of the VA Cooperative Studies Program. To identify and test new drug..., ``Drug Development Initiative'' (DDI), for New Pharmacological Treatments for Post-Traumatic Stress... will delineate the collaboration for PTSD treatment intended to test new drugs to benefit Veterans...

Optimization of drug-drug interaction alert rules in a pediatric hospital's electronic health record system using a visual analytics dashboard.

PubMed

Simpao, Allan F; Ahumada, Luis M; Desai, Bimal R; Bonafide, Christopher P; Gálvez, Jorge A; Rehman, Mohamed A; Jawad, Abbas F; Palma, Krisha L; Shelov, Eric D

2015-03-01

To develop and evaluate an electronic dashboard of hospital-wide electronic health record medication alerts for an alert fatigue reduction quality improvement project. We used visual analytics software to develop the dashboard. We collaborated with the hospital-wide Clinical Decision Support committee to perform three interventions successively deactivating clinically irrelevant drug-drug interaction (DDI) alert rules. We analyzed the impact of the interventions on care providers' and pharmacists' alert and override rates using an interrupted time series framework with piecewise regression. We evaluated 2 391 880 medication alerts between January 31, 2011 and January 26, 2014. For pharmacists, the median alert rate prior to the first DDI deactivation was 58.74 alerts/100 orders (IQR 54.98-60.48) and 25.11 alerts/100 orders (IQR 23.45-26.57) following the three interventions (p<0.001). For providers, baseline median alert rate prior to the first round of DDI deactivation was 19.73 alerts/100 orders (IQR 18.66-20.24) and 15.11 alerts/100 orders (IQR 14.44-15.49) following the three interventions (p<0.001). In a subgroup analysis, we observed a decrease in pharmacists' override rates for DDI alerts that were not modified in the system from a median of 93.06 overrides/100 alerts (IQR 91.96-94.33) to 85.68 overrides/100 alerts (IQR 84.29-87.15, p<0.001). The medication serious safety event rate decreased during the study period, and there were no serious safety events reported in association with the deactivated alert rules. An alert dashboard facilitated safe rapid-cycle reductions in alert burden that were temporally associated with lower pharmacist override rates in a subgroup of DDIs not directly affected by the interventions; meanwhile, the pharmacists' frequency of selecting the 'cancel' option increased. We hypothesize that reducing the alert burden enabled pharmacists to devote more attention to clinically relevant alerts. © The Author 2014. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Application of Receiver Operating Characteristic Analysis to Refine the Prediction of Potential Digoxin Drug Interactions

PubMed Central

Ellens, Harma; Deng, Shibing; Coleman, JoAnn; Bentz, Joe; Taub, Mitchell E.; Ragueneau-Majlessi, Isabelle; Chung, Sophie P.; Herédi-Szabó, Krisztina; Neuhoff, Sibylle; Palm, Johan; Balimane, Praveen; Zhang, Lei; Jamei, Masoud; Hanna, Imad; O’Connor, Michael; Bednarczyk, Dallas; Forsgard, Malin; Chu, Xiaoyan; Funk, Christoph; Guo, Ailan; Hillgren, Kathleen M.; Li, LiBin; Pak, Anne Y.; Perloff, Elke S.; Rajaraman, Ganesh; Salphati, Laurent; Taur, Jan-Shiang; Weitz, Dietmar; Wortelboer, Heleen M.; Xia, Cindy Q.; Xiao, Guangqing; Yamagata, Tetsuo

2013-01-01

In the 2012 Food and Drug Administration (FDA) draft guidance on drug-drug interactions (DDIs), a new molecular entity that inhibits P-glycoprotein (P-gp) may need a clinical DDI study with a P-gp substrate such as digoxin when the maximum concentration of inhibitor at steady state divided by IC50 ([I1]/IC50) is ≥0.1 or concentration of inhibitor based on highest approved dose dissolved in 250 ml divide by IC50 ([I2]/IC50) is ≥10. In this article, refined criteria are presented, determined by receiver operating characteristic analysis, using IC50 values generated by 23 laboratories. P-gp probe substrates were digoxin for polarized cell-lines and N-methyl quinidine or vinblastine for P-gp overexpressed vesicles. Inhibition of probe substrate transport was evaluated using 15 known P-gp inhibitors. Importantly, the criteria derived in this article take into account variability in IC50 values. Moreover, they are statistically derived based on the highest degree of accuracy in predicting true positive and true negative digoxin DDI results. The refined criteria of [I1]/IC50 ≥ 0.03 and [I2]/IC50 ≥ 45 and FDA criteria were applied to a test set of 101 in vitro-in vivo digoxin DDI pairs collated from the literature. The number of false negatives (none predicted but DDI observed) were similar, 10 and 12%, whereas the number of false positives (DDI predicted but not observed) substantially decreased from 51 to 40%, relative to the FDA criteria. On the basis of estimated overall variability in IC50 values, a theoretical 95% confidence interval calculation was developed for single laboratory IC50 values, translating into a range of [I1]/IC50 and [I2]/IC50 values. The extent by which this range falls above the criteria is a measure of risk associated with the decision, attributable to variability in IC50 values. PMID:23620486

Interaction between amiodarone and hepatitis-C virus nucleotide inhibitors in human induced pluripotent stem cell-derived cardiomyocytes and HEK-293 Cav1.2 over-expressing cells.

PubMed

Lagrutta, Armando; Zeng, Haoyu; Imredy, John; Balasubramanian, Bharathi; Dech, Spencer; Lis, Edward; Wang, Jixin; Zhai, Jin; DeGeorge, Joseph; Sannajust, Frederick

2016-10-01

Several clinical cases of severe bradyarrhythmias have been reported upon co-administration of the Hepatitis-C NS5B Nucleotide Polymerase Inhibitor (HCV-NI) direct-acting antiviral agent, sofosbuvir (SOF), and the Class-III anti-arrhythmic amiodarone (AMIO). We model the cardiac drug-drug interaction (DDI) between AMIO and SOF, and between AMIO and a closely-related SOF analog, MNI-1 (Merck Nucleotide Inhibitor #1), in functional assays of human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs), to provide mechanistic insights into recently reported clinical cases. AMIO co-applied with SOF or MNI-1 increased beating rate or field potential (FP) rate and decreased impedance (IMP) and Ca(2+) transient amplitudes in hiPSC-CM syncytia. This action resembled that of Ca(2+) channel blockers (CCBs) in the model, but CCBs did not substitute for AMIO in the DDI. AMIO analog dronedarone (DRON) did not substitute for, but competed with AMIO in the DDI. Ryanodine and thapsigargin, decreasing intracellular Ca(2+) stores, and SEA-0400, a Na(+)/Ca(2+) exchanger-1 (NCX1) inhibitor, partially antagonized or suppressed DDI effects. Other agents affecting FP rate only exerted additive or subtractive effects, commensurate with their individual effects. We also describe an interaction between AMIO and MNI-1 on Cav1.2 ion channels in an over-expressing HEK-293 cell line. MNI-1 enhanced Cav1.2 channel inhibition by AMIO, but did not affect inhibition of Cav1.2 by DRON, verapamil, nifedipine, or diltiazem. Our data in hiPSC-CMs indicate that HCV-NI agents such as SOF and MNI-1 interact with key intracellular Ca(2+)-handling mechanisms. Additional study in a Cav1.2 HEK-293 cell-line suggests that HCV-NIs potentiate the inhibitory action of AMIO on L-type Ca(2+) channels. Copyright © 2016 Elsevier Inc. All rights reserved.

Effects of Type 2 Diabetes Mellitus in Patients on Treatment With Glibenclamide and Metformin on Carvedilol Enantiomers Metabolism.

PubMed

Nardotto, Glauco H B; Coelho, Eduardo B; Paiva, Carlos E; Lanchote, Vera L

2017-06-01

Carvedilol is available in clinical practice as a racemate in which (S)-(-)-carvedilol is a β- and α 1 -adrenergic antagonist and (R)-(+)-carvedilol is only an α 1 -adrenergic antagonist. Carvedilol is mainly metabolized by glucuronidation, by CYP2D6 to hydroxyphenylcarvedilol (OHC), and by CYP2C9 to O-desmethylcarvedilol (DMC). This study evaluated the pharmacokinetics of carvedilol enantiomers and their metabolites OHC and DMC in healthy volunteers (n = 13) and in type 2 diabetes mellitus patients with good glycemic control (n = 13). The healthy subjects were enrolled to receive either a 25-mg oral single dose of carvedilol alone (no DDI) or carvedilol simultaneously with 5 mg glibenclamide and 500 mg metformin (DDI), whereas type 2 diabetes mellitus patients who were on long-term treatment with glibenclamide (5 mg/8 h) and metformin (500 mg/8 h) were enrolled to receive only a single oral dose of 25 mg carvedilol. The plasma concentrations of the (R)-(+)-carvedilol, (R)-(+)-DMC, and (R)-(+)-OHC were higher than those of (S)-(-)-carvedilol, (S)-(-)-DMC, and (S)-(-)-OHC in all investigated groups. The pharmacokinetics of the carvedilol enantiomers did not differ between the groups. However, the AUC values of the DMC enantiomers were lower in the type 2 diabetes mellitus patients than in the healthy volunteers (DDI and no DDI) [(R)-(+), 6.9, 10.4, 11.9 ng·h/mL; and (S)-(-), 2.4, 4.3, 4.0 ng·h/mL, respectively]. In contrast, the AUC values of the OHC enantiomers were higher in the type 2 diabetes mellitus patients [(R)-(+), 13.9, 6.6, 4.9 ng·h/mL; and (S)-(-), 7.2, 1.5, 1.5 ng·h/mL], which explains the fact that the carvedilol pharmacokinetics was unchanged. © 2017, The American College of Clinical Pharmacology.

Knowledge Integration and Use-Case Analysis for a Customized Drug-Drug Interaction CDS Service

NASA Astrophysics Data System (ADS)

Kam, Hye Jin; Park, Man Young; Kim, Woojae; Yoon, Duk Yong; Ahn, Eun Kyoung; Park, Rae Woong

Clinical decision support systems (CDSSs) are thought to reduce adverse drug events (ADEs) by monitoring drug-drug interactions(DDIs). However, clinically improper or excessive alerts can result in high alert overrides. A tailored CDS service, which is appropriate for clinicians and their ordering situations, is required to increase alert acceptance. In this study, we conducted a 12-week pilot project adopting a tailed CDSS at an emergency department. The new CDSS was conducted via a stepwise integration of additional new rules. The alert status with changes in acceptance rate was analyzed. The most frequent DDI alerts were related to prescriptions of anti-inflammatory drugs. The percentages of alert overrides for each stage were 98.0%, 96.0%, 96.9%, and 98.1%, respectively. 91.5% of overridden alerts were related to discharge medications. To reduce the potential hazards of ADEs, the development of an effective customized DDI CDSS is required, via in-depth analysis on alert patterns and overridden reasons.

Consensus Recommendations for Systematic Evaluation of Drug-Drug Interaction Evidence for Clinical Decision Support

PubMed Central

Scheife, Richard T.; Hines, Lisa E.; Boyce, Richard D.; Chung, Sophie P.; Momper, Jeremiah; Sommer, Christine D.; Abernethy, Darrell R.; Horn, John; Sklar, Stephen J.; Wong, Samantha K.; Jones, Gretchen; Brown, Mary; Grizzle, Amy J.; Comes, Susan; Wilkins, Tricia Lee; Borst, Clarissa; Wittie, Michael A.; Rich, Alissa; Malone, Daniel C.

2015-01-01

Background Healthcare organizations, compendia, and drug knowledgebase vendors use varying methods to evaluate and synthesize evidence on drug-drug interactions (DDIs). This situation has a negative effect on electronic prescribing and medication information systems that warn clinicians of potentially harmful medication combinations. Objective To provide recommendations for systematic evaluation of evidence from the scientific literature, drug product labeling, and regulatory documents with respect to DDIs for clinical decision support. Methods A conference series was conducted to develop a structured process to improve the quality of DDI alerting systems. Three expert workgroups were assembled to address the goals of the conference. The Evidence Workgroup consisted of 15 individuals with expertise in pharmacology, drug information, biomedical informatics, and clinical decision support. Workgroup members met via webinar from January 2013 to February 2014. Two in-person meetings were conducted in May and September 2013 to reach consensus on recommendations. Results We developed expert-consensus answers to three key questions: 1) What is the best approach to evaluate DDI evidence?; 2) What evidence is required for a DDI to be applicable to an entire class of drugs?; and 3) How should a structured evaluation process be vetted and validated? Conclusion Evidence-based decision support for DDIs requires consistent application of transparent and systematic methods to evaluate the evidence. Drug information systems that implement these recommendations should be able to provide higher quality information about DDIs in drug compendia and clinical decision support tools. PMID:25556085

Core drug-drug interaction alerts for inclusion in pediatric electronic health records with computerized prescriber order entry.

PubMed

Harper, Marvin B; Longhurst, Christopher A; McGuire, Troy L; Tarrago, Rod; Desai, Bimal R; Patterson, Al

2014-03-01

The study aims to develop a core set of pediatric drug-drug interaction (DDI) pairs for which electronic alerts should be presented to prescribers during the ordering process. A clinical decision support working group composed of Children's Hospital Association (CHA) members was developed. CHA Pharmacists and Chief Medical Information Officers participated. Consensus was reached on a core set of 19 DDI pairs that should be presented to pediatric prescribers during the order process. We have provided a core list of 19 high value drug pairs for electronic drug-drug interaction alerts to be recommended for inclusion as high value alerts in prescriber order entry software used with a pediatric patient population. We believe this list represents the most important pediatric drug interactions for practical implementation within computerized prescriber order entry systems.

Development, Verification, and Prediction of Osimertinib Drug-Drug Interactions Using PBPK Modeling Approach to Inform Drug Label.

PubMed

Pilla Reddy, Venkatesh; Walker, Michael; Sharma, Pradeep; Ballard, Peter; Vishwanathan, Karthick

2018-02-22

Osimertinib is a potent, highly selective, irreversible inhibitor of epidermal growth factor receptor (EGFR) and T790M resistance mutation. In vitro metabolism data suggested osimertinib is a substrate of cytochrome P450 (CYP)3A4/5, a weak inducer of CYP3A, and an inhibitor of breast cancer resistance protein (BCRP). A combination of in vitro data, clinical pharmacokinetic data, and drug-drug interaction (DDI) data of osimertinib in oncology patients were used to develop the physiologically based pharmacokinetic (PBPK) model and verify the DDI data of osimertinib. The model predicted the observed monotherapy concentration profile of osimertinib within 1.1-fold, and showed good predictability (within 1.7-fold) to the observed peak plasma concentration (C max ) and area under the curve (AUC) DDI ratio changes, when co-administered with rifampicin, itraconazole, and simvastatin, but not with rosuvastatin. Based on observed clinical data and PBPK simulations, the recommended dose of osimertinib when dosed with strong CYP3A inducers is 160 mg once daily. PBPK modeling suggested no dose adjustment with moderate and weak CYP3A inducers. © 2018 The Authors CPT: Pharmacometrics & Systems Pharmacology published by Wiley Periodicals, Inc. on behalf of American Society for CPT: Pharmacometrics & Systems Pharmacology.

Evaluation of alternative intersections and interchanges: volume 2 -- diverging diamond interchange signal timing.

DOT National Transportation Integrated Search

2015-12-01

This report presents findings from field studies of operations at diverging diamond interchanges (DDIs) in Salt Lake City, Utah and Fort : Wayne, Indiana. These discuss optimization of signal offsets both within the DDI, and with the DDI integrated a...

Efficacy and safety of three antiretroviral regimens for initial treatment of HIV-1: a randomized clinical trial in diverse multinational settings.

PubMed

Campbell, Thomas B; Smeaton, Laura M; Kumarasamy, N; Flanigan, Timothy; Klingman, Karin L; Firnhaber, Cynthia; Grinsztejn, Beatriz; Hosseinipour, Mina C; Kumwenda, Johnstone; Lalloo, Umesh; Riviere, Cynthia; Sanchez, Jorge; Melo, Marineide; Supparatpinyo, Khuanchai; Tripathy, Srikanth; Martinez, Ana I; Nair, Apsara; Walawander, Ann; Moran, Laura; Chen, Yun; Snowden, Wendy; Rooney, James F; Uy, Jonathan; Schooley, Robert T; De Gruttola, Victor; Hakim, James Gita

2012-01-01

Antiretroviral regimens with simplified dosing and better safety are needed to maximize the efficiency of antiretroviral delivery in resource-limited settings. We investigated the efficacy and safety of antiretroviral regimens with once-daily compared to twice-daily dosing in diverse areas of the world. 1,571 HIV-1-infected persons (47% women) from nine countries in four continents were assigned with equal probability to open-label antiretroviral therapy with efavirenz plus lamivudine-zidovudine (EFV+3TC-ZDV), atazanavir plus didanosine-EC plus emtricitabine (ATV+DDI+FTC), or efavirenz plus emtricitabine-tenofovir-disoproxil fumarate (DF) (EFV+FTC-TDF). ATV+DDI+FTC and EFV+FTC-TDF were hypothesized to be non-inferior to EFV+3TC-ZDV if the upper one-sided 95% confidence bound for the hazard ratio (HR) was ≤1.35 when 30% of participants had treatment failure. An independent monitoring board recommended stopping study follow-up prior to accumulation of 472 treatment failures. Comparing EFV+FTC-TDF to EFV+3TC-ZDV, during a median 184 wk of follow-up there were 95 treatment failures (18%) among 526 participants versus 98 failures among 519 participants (19%; HR 0.95, 95% CI 0.72-1.27; p = 0.74). Safety endpoints occurred in 243 (46%) participants assigned to EFV+FTC-TDF versus 313 (60%) assigned to EFV+3TC-ZDV (HR 0.64, CI 0.54-0.76; p<0.001) and there was a significant interaction between sex and regimen safety (HR 0.50, CI 0.39-0.64 for women; HR 0.79, CI 0.62-1.00 for men; p = 0.01). Comparing ATV+DDI+FTC to EFV+3TC-ZDV, during a median follow-up of 81 wk there were 108 failures (21%) among 526 participants assigned to ATV+DDI+FTC and 76 (15%) among 519 participants assigned to EFV+3TC-ZDV (HR 1.51, CI 1.12-2.04; p = 0.007). EFV+FTC-TDF had similar high efficacy compared to EFV+3TC-ZDV in this trial population, recruited in diverse multinational settings. Superior safety, especially in HIV-1-infected women, and once-daily dosing of EFV+FTC-TDF are advantageous for use of this regimen for initial treatment of HIV-1 infection in resource-limited countries. ATV+DDI+FTC had inferior efficacy and is not recommended as an initial antiretroviral regimen. www.ClinicalTrials.gov NCT00084136. Please see later in the article for the Editors' Summary.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lagrutta, Armando, E-mail: armando_lagrutta@merck.

Several clinical cases of severe bradyarrhythmias have been reported upon co-administration of the Hepatitis-C NS5B Nucleotide Polymerase Inhibitor (HCV-NI) direct-acting antiviral agent, sofosbuvir (SOF), and the Class-III anti-arrhythmic amiodarone (AMIO). We model the cardiac drug-drug interaction (DDI) between AMIO and SOF, and between AMIO and a closely-related SOF analog, MNI-1 (Merck Nucleotide Inhibitor #1), in functional assays of human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs), to provide mechanistic insights into recently reported clinical cases. AMIO co-applied with SOF or MNI-1 increased beating rate or field potential (FP) rate and decreased impedance (IMP) and Ca{sup 2+} transient amplitudes in hiPSC-CM syncytia.more » This action resembled that of Ca{sup 2+} channel blockers (CCBs) in the model, but CCBs did not substitute for AMIO in the DDI. AMIO analog dronedarone (DRON) did not substitute for, but competed with AMIO in the DDI. Ryanodine and thapsigargin, decreasing intracellular Ca{sup 2+} stores, and SEA-0400, a Na{sup +}/Ca{sup 2+} exchanger-1 (NCX1) inhibitor, partially antagonized or suppressed DDI effects. Other agents affecting FP rate only exerted additive or subtractive effects, commensurate with their individual effects. We also describe an interaction between AMIO and MNI-1 on Cav{sub 1.2} ion channels in an over-expressing HEK-293 cell line. MNI-1 enhanced Cav{sub 1.2} channel inhibition by AMIO, but did not affect inhibition of Cav{sub 1.2} by DRON, verapamil, nifedipine, or diltiazem. Our data in hiPSC-CMs indicate that HCV-NI agents such as SOF and MNI-1 interact with key intracellular Ca{sup 2+}-handling mechanisms. Additional study in a Cav{sub 1.2} HEK-293 cell-line suggests that HCV-NIs potentiate the inhibitory action of AMIO on L-type Ca{sup 2+} channels. - Highlights: • Adverse clinical interaction between amiodarone and HCV-NI drugs is captured by in vitro models. • Human iPSC-derived cardiomyocyte beating syncytial model points to Ca{sup 2+} handling effects. • Overexpressing human Ca{sup 2+} channel line model points to shifts in Ca{sup 2+} influx. • Shifts in Ca{sup 2+} current voltage-dependent inactivation play a role in the AER interaction.« less

Drug-drug interactions and adverse drug reactions in polypharmacy among older adults: an integrative review 1

PubMed Central

Rodrigues, Maria Cristina Soares; de Oliveira, Cesar

2016-01-01

ABSTRACT Objective: to identify and summarize studies examining both drug-drug interactions (DDI) and adverse drug reactions (ADR) in older adults polymedicated. Methods: an integrative review of studies published from January 2008 to December 2013, according to inclusion and exclusion criteria, in MEDLINE and EMBASE electronic databases were performed. Results: forty-seven full-text studies including 14,624,492 older adults (≥ 60 years) were analyzed: 24 (51.1%) concerning ADR, 14 (29.8%) DDI, and 9 studies (19.1%) investigating both DDI and ADR. We found a variety of methodological designs. The reviewed studies reinforced that polypharmacy is a multifactorial process, and predictors and inappropriate prescribing are associated with negative health outcomes, as increasing the frequency and types of ADRs and DDIs involving different drug classes, moreover, some studies show the most successful interventions to optimize prescribing. Conclusions: DDI and ADR among older adults continue to be a significant issue in the worldwide. The findings from the studies included in this integrative review, added to the previous reviews, can contribute to the improvement of advanced practices in geriatric nursing, to promote the safety of older patients in polypharmacy. However, more research is needed to elucidate gaps. PMID:27598380

Waveguide transport mediated by strong coupling with atoms

NASA Astrophysics Data System (ADS)

Cheng, Mu-Tian; Xu, Jingping; Agarwal, Girish S.

2017-05-01

We investigate single-photon scattering properties in a one-dimensional waveguide coupled to a quantum emitter's chain with dipole-dipole interaction (DDI). The photon transport is extremely sensitive to the location of the evanescently coupled atoms. The analytical expressions of reflection and transmission amplitudes for the chain containing two emitters with DDI are deduced by using a real-space Hamiltonian. Two cases, where the two emitters symmetrically or asymmetrically couple to the waveguide, are discussed in detail. It shows that the reflection and transmission typical spectra split into two peaks due to the DDI. The Fano minimum in the spectra can be used to estimate the strength of the DDI. Furthermore, the DDI makes spectra strongly asymmetric and creates a transmission window in the region where there was zero transmission. The scattering spectra for the chain consisting of multiple emitters are also given. Our key finding is that DDI can broaden the frequency bandwidth for high reflection when the chain consists of many emitters.

A linguistic rule-based approach to extract drug-drug interactions from pharmacological documents.

PubMed

Segura-Bedmar, Isabel; Martínez, Paloma; de Pablo-Sánchez, César

2011-03-29

A drug-drug interaction (DDI) occurs when one drug influences the level or activity of another drug. The increasing volume of the scientific literature overwhelms health care professionals trying to be kept up-to-date with all published studies on DDI. This paper describes a hybrid linguistic approach to DDI extraction that combines shallow parsing and syntactic simplification with pattern matching. Appositions and coordinate structures are interpreted based on shallow syntactic parsing provided by the UMLS MetaMap tool (MMTx). Subsequently, complex and compound sentences are broken down into clauses from which simple sentences are generated by a set of simplification rules. A pharmacist defined a set of domain-specific lexical patterns to capture the most common expressions of DDI in texts. These lexical patterns are matched with the generated sentences in order to extract DDIs. We have performed different experiments to analyze the performance of the different processes. The lexical patterns achieve a reasonable precision (67.30%), but very low recall (14.07%). The inclusion of appositions and coordinate structures helps to improve the recall (25.70%), however, precision is lower (48.69%). The detection of clauses does not improve the performance. Information Extraction (IE) techniques can provide an interesting way of reducing the time spent by health care professionals on reviewing the literature. Nevertheless, no approach has been carried out to extract DDI from texts. To the best of our knowledge, this work proposes the first integral solution for the automatic extraction of DDI from biomedical texts.

The ddY mouse: a model of postprandial hypertriglyceridemia in response to dietary fat

PubMed Central

Yamazaki, Tomomi; Kishimoto, Kyoko; Ezaki, Osamu

2012-01-01

Postprandial hyperlipidemia (lipemia) is a risk factor for atherosclerosis. However, mouse models of postprandial hyperlipidemia have not been reported. Here, we report that ddY mice display marked postprandial hypertriglyceridemia in response to dietary fat. In ddY mice, the fasting serum total triacylglyceride (TG) concentration was 134 mg/dl, which increased to 571 mg/dl after an intragastric safflower oil load (0.4 ml/mouse). In C57BL/6J mice, these concentrations were 57 and 106 mg/dl, respectively. By lipoprotein analysis, ddY mice showed increases in chylomicron- and VLDL-sized TG fractions (remnants and VLDL) after fat load. In C57BL/6J mice, post-heparin plasma LPL activity after fat load was increased 4.8-fold relative to fasting. However, in ddY mice, the increase of LPL activity after fat load was very small (1.2-fold) and not significant. High fat feeding for 10 weeks led to obesity in ddY mice. A difference in LPL amino acid composition between C57BL/6J and ddY mice was detected but was deemed unlikely to cause hypertriglyceridemia because hypertriglyceridemia was not evident in other strains harboring the ddY-type LPL sequence. These findings indicate that postprandial hypertriglyceridemia in ddY mice is induced by decreased LPL activity after fat load and is associated with obesity induced by a high-fat diet. PMID:22735545

Physiologically Based Pharmacokinetic Modeling Suggests Limited Drug–Drug Interaction Between Clopidogrel and Dasabuvir

PubMed Central

Fu, W; Badri, P; Bow, DAJ; Fischer, V

2017-01-01

Dasabuvir, a nonnucleoside NS5B polymerase inhibitor, is a sensitive substrate of cytochrome P450 (CYP) 2C8 with a potential for drug–drug interaction (DDI) with clopidogrel. A physiologically based pharmacokinetic (PBPK) model was developed for dasabuvir to evaluate the DDI potential with clopidogrel, the acyl‐β‐D glucuronide metabolite of which has been reported as a strong mechanism‐based inhibitor of CYP2C8 based on an interaction with repaglinide. In addition, the PBPK model for clopidogrel and its metabolite were updated with additional in vitro data. Sensitivity analyses using these PBPK models suggested that CYP2C8 inhibition by clopidogrel acyl‐β‐D glucuronide may not be as potent as previously suggested. The dasabuvir and updated clopidogrel PBPK models predict a moderate increase of 1.5–1.9‐fold for Cmax and 1.9–2.8‐fold for AUC of dasabuvir when coadministered with clopidogrel. While the PBPK results suggest there is a potential for DDI between dasabuvir and clopidogrel, the magnitude is not expected to be clinically relevant. PMID:28411400

Sex-Divergent Clinical Outcomes and Precision Medicine: An Important New Role for Institutional Review Boards and Research Ethics Committees.

PubMed

Segarra, Ignacio; Modamio, Pilar; Fernández, Cecilia; Mariño, Eduardo L

2017-01-01

The efforts toward individualized medicine have constantly increased in an attempt to improve treatment options. These efforts have led to the development of small molecules which target specific molecular pathways involved in cancer progression. We have reviewed preclinical studies of sunitinib that incorporate sex as a covariate to explore possible sex-based differences in pharmacokinetics and drug-drug interactions (DDI) to attempt a relationship with published clinical outputs. We observed that covariate sex is lacking in most clinical outcome reports and suggest a series of ethic-based proposals to improve research activities and identify relevant different sex outcomes. We propose a deeper integration of preclinical, clinical, and translational research addressing statistical and clinical significance jointly; to embed specific sex-divergent endpoints to evaluate possible gender differences objectively during all stages of research; to pay greater attention to sex-divergent outcomes in polypharmacy scenarios, DDI and bioequivalence studies; the clear reporting of preclinical and clinical findings regarding sex-divergent outcomes; as well as to encourage the active role of scientists and the pharmaceutical industry to foster a new scientific culture through their research programs, practice, and participation in editorial boards and Institutional Ethics Review Boards (IRBs) and Research Ethics Committees (RECs). We establish the IRB/REC as the centerpiece for the implementation of these proposals. We suggest the expansion of its competence to follow up clinical trials to ensure that sex differences are addressed and recognized; to engage in data monitoring committees to improve clinical research cooperation and ethically address those potential clinical outcome differences between male and female patients to analyze their social and clinical implications in research and healthcare policies.

Sex-Divergent Clinical Outcomes and Precision Medicine: An Important New Role for Institutional Review Boards and Research Ethics Committees

PubMed Central

Segarra, Ignacio; Modamio, Pilar; Fernández, Cecilia; Mariño, Eduardo L.

2017-01-01

The efforts toward individualized medicine have constantly increased in an attempt to improve treatment options. These efforts have led to the development of small molecules which target specific molecular pathways involved in cancer progression. We have reviewed preclinical studies of sunitinib that incorporate sex as a covariate to explore possible sex-based differences in pharmacokinetics and drug–drug interactions (DDI) to attempt a relationship with published clinical outputs. We observed that covariate sex is lacking in most clinical outcome reports and suggest a series of ethic-based proposals to improve research activities and identify relevant different sex outcomes. We propose a deeper integration of preclinical, clinical, and translational research addressing statistical and clinical significance jointly; to embed specific sex-divergent endpoints to evaluate possible gender differences objectively during all stages of research; to pay greater attention to sex-divergent outcomes in polypharmacy scenarios, DDI and bioequivalence studies; the clear reporting of preclinical and clinical findings regarding sex-divergent outcomes; as well as to encourage the active role of scientists and the pharmaceutical industry to foster a new scientific culture through their research programs, practice, and participation in editorial boards and Institutional Ethics Review Boards (IRBs) and Research Ethics Committees (RECs). We establish the IRB/REC as the centerpiece for the implementation of these proposals. We suggest the expansion of its competence to follow up clinical trials to ensure that sex differences are addressed and recognized; to engage in data monitoring committees to improve clinical research cooperation and ethically address those potential clinical outcome differences between male and female patients to analyze their social and clinical implications in research and healthcare policies. PMID:28785221

Microscopic analysis of homogeneous electron gas by considering dipole-dipole interaction

NASA Astrophysics Data System (ADS)

Bordbar, G. H.; Pouresmaeeli, F.

2017-12-01

Implying perturbation theory, the impact of the dipole-dipole interaction (DDI) on the thermodynamic properties of a homogeneous electron gas at zero temperature is investigated. Through the second quantization formalism, the analytic expressions for the ground state energy and the DDI energy are obtained. In this paper, the DDI energy has similarities with the previous works done by others. We show that its general behavior depends on density and the total angular momentum. Especially, it is found that the DDI energy has a highly state-dependent behavior. With the growth of density, the magnitude of DDI energy, which is found to be the summation of all energy contributions of the states with even and odd total angular momenta, grows linearly. It is also found that for the states with even and odd total angular momenta, the DDI energy contributions are corresponding to the positive and negative values, respectively. In particular, an increase of total angular momentum leads to decline in the magnitude of energy contribution. Therefore, the dipole-dipole interaction reveals distinct characteristics in comparison with central-like interactions.

ReaDDy - A Software for Particle-Based Reaction-Diffusion Dynamics in Crowded Cellular Environments

PubMed Central

Schöneberg, Johannes; Noé, Frank

2013-01-01

We introduce the software package ReaDDy for simulation of detailed spatiotemporal mechanisms of dynamical processes in the cell, based on reaction-diffusion dynamics with particle resolution. In contrast to other particle-based reaction kinetics programs, ReaDDy supports particle interaction potentials. This permits effects such as space exclusion, molecular crowding and aggregation to be modeled. The biomolecules simulated can be represented as a sphere, or as a more complex geometry such as a domain structure or polymer chain. ReaDDy bridges the gap between small-scale but highly detailed molecular dynamics or Brownian dynamics simulations and large-scale but little-detailed reaction kinetics simulations. ReaDDy has a modular design that enables the exchange of the computing core by efficient platform-specific implementations or dynamical models that are different from Brownian dynamics. PMID:24040218

A linguistic rule-based approach to extract drug-drug interactions from pharmacological documents

PubMed Central

2011-01-01

Background A drug-drug interaction (DDI) occurs when one drug influences the level or activity of another drug. The increasing volume of the scientific literature overwhelms health care professionals trying to be kept up-to-date with all published studies on DDI. Methods This paper describes a hybrid linguistic approach to DDI extraction that combines shallow parsing and syntactic simplification with pattern matching. Appositions and coordinate structures are interpreted based on shallow syntactic parsing provided by the UMLS MetaMap tool (MMTx). Subsequently, complex and compound sentences are broken down into clauses from which simple sentences are generated by a set of simplification rules. A pharmacist defined a set of domain-specific lexical patterns to capture the most common expressions of DDI in texts. These lexical patterns are matched with the generated sentences in order to extract DDIs. Results We have performed different experiments to analyze the performance of the different processes. The lexical patterns achieve a reasonable precision (67.30%), but very low recall (14.07%). The inclusion of appositions and coordinate structures helps to improve the recall (25.70%), however, precision is lower (48.69%). The detection of clauses does not improve the performance. Conclusions Information Extraction (IE) techniques can provide an interesting way of reducing the time spent by health care professionals on reviewing the literature. Nevertheless, no approach has been carried out to extract DDI from texts. To the best of our knowledge, this work proposes the first integral solution for the automatic extraction of DDI from biomedical texts. PMID:21489220

Extraction of Pharmacokinetic Evidence of Drug–Drug Interactions from the Literature

PubMed Central

Kolchinsky, Artemy; Lourenço, Anália; Wu, Heng-Yi; Li, Lang; Rocha, Luis M.

2015-01-01

Drug-drug interaction (DDI) is a major cause of morbidity and mortality and a subject of intense scientific interest. Biomedical literature mining can aid DDI research by extracting evidence for large numbers of potential interactions from published literature and clinical databases. Though DDI is investigated in domains ranging in scale from intracellular biochemistry to human populations, literature mining has not been used to extract specific types of experimental evidence, which are reported differently for distinct experimental goals. We focus on pharmacokinetic evidence for DDI, essential for identifying causal mechanisms of putative interactions and as input for further pharmacological and pharmacoepidemiology investigations. We used manually curated corpora of PubMed abstracts and annotated sentences to evaluate the efficacy of literature mining on two tasks: first, identifying PubMed abstracts containing pharmacokinetic evidence of DDIs; second, extracting sentences containing such evidence from abstracts. We implemented a text mining pipeline and evaluated it using several linear classifiers and a variety of feature transforms. The most important textual features in the abstract and sentence classification tasks were analyzed. We also investigated the performance benefits of using features derived from PubMed metadata fields, various publicly available named entity recognizers, and pharmacokinetic dictionaries. Several classifiers performed very well in distinguishing relevant and irrelevant abstracts (reaching F1≈0.93, MCC≈0.74, iAUC≈0.99) and sentences (F1≈0.76, MCC≈0.65, iAUC≈0.83). We found that word bigram features were important for achieving optimal classifier performance and that features derived from Medical Subject Headings (MeSH) terms significantly improved abstract classification. We also found that some drug-related named entity recognition tools and dictionaries led to slight but significant improvements, especially in classification of evidence sentences. Based on our thorough analysis of classifiers and feature transforms and the high classification performance achieved, we demonstrate that literature mining can aid DDI discovery by supporting automatic extraction of specific types of experimental evidence. PMID:25961290

Which Variables Associated with Data-Driven Instruction Are Believed to Best Predict Urban Student Achievement?

ERIC Educational Resources Information Center

Greer, Wil

2013-01-01

This study identified the variables associated with data-driven instruction (DDI) that are perceived to best predict student achievement. Of the DDI variables discussed in the literature, 51 of them had a sufficient enough research base to warrant statistical analysis. Of them, 26 were statistically significant. Multiple regression and an…

The Distress Disclosure Index: A Research Review and Multitrait-Multimethod Examination

ERIC Educational Resources Information Center

Kahn, Jeffrey H.; Hucke, Brandy E.; Bradley, Allyson M.; Glinski, Austin J.; Malak, Brittany L.

2012-01-01

The Distress Disclosure Index (DDI; J. H. Kahn & R. M. Hessling, 2001) is a brief self-report measure of one's tendency to disclose personally distressing information. The purpose of this article was to summarize what is known about the DDI, present new validity evidence, and make recommendations for use of the DDI. This article reviews research…

Efficacy and Safety of Three Antiretroviral Regimens for Initial Treatment of HIV-1: A Randomized Clinical Trial in Diverse Multinational Settings

PubMed Central

Campbell, Thomas B.; Smeaton, Laura M.; Kumarasamy, N.; Flanigan, Timothy; Klingman, Karin L.; Firnhaber, Cynthia; Grinsztejn, Beatriz; Hosseinipour, Mina C.; Kumwenda, Johnstone; Lalloo, Umesh; Riviere, Cynthia; Sanchez, Jorge; Melo, Marineide; Supparatpinyo, Khuanchai; Tripathy, Srikanth; Martinez, Ana I.; Nair, Apsara; Walawander, Ann; Moran, Laura; Chen, Yun; Snowden, Wendy; Rooney, James F.; Uy, Jonathan; Schooley, Robert T.; De Gruttola, Victor; Hakim, James Gita; Swann, Edith; Barnett, Ronald L.; Brizz, Barbara; Delph, Yvette; Gettinger, Nikki; Mitsuyasu, Ronald T.; Eshleman, Susan; Safren, Steven; Fiscus, Susan A.; Andrade, Adriana; Haas, David W.; Amod, Farida; Berthaud, Vladimir; Bollinger, Robert C.; Bryson, Yvonne; Celentano, David; Chilongozi, David; Cohen, Myron; Collier, Ann C.; Currier, Judith Silverstein; Cu-Uvin, Susan; Eron, Joseph; Flexner, Charles; Gallant, Joel E.; Gulick, Roy M.; Hammer, Scott M.; Hoffman, Irving; Kazembe, Peter; Kumwenda, Newton; Lama, Javier R.; Lawrence, Jody; Maponga, Chiedza; Martinson, Francis; Mayer, Kenneth; Nielsen, Karin; Pendame, Richard B.; Ramratnam, Bharat; Sanne, Ian; Severe, Patrice; Sirisanthana, Thira; Solomon, Suniti; Tabet, Steve; Taha, Taha; van der Horst, Charles; Wanke, Christine; Gormley, Joan; Marcus, Cheryl J.; Putnam, Beverly; Loeliger, Edde; Pappa, Keith A.; Webb, Nancy; Shugarts, David L.; Winters, Mark A.; Descallar, Renard S.; Steele, Joseph; Wulfsohn, Michael; Said, Farideh; Chen, Yue; Martin, John C; Bischofberger, Norbert; Cheng, Andrew; Jaffe, Howard; Sharma, Jabin; Poongulali, S.; Cardoso, Sandra Wagner; Faria, Deise Lucia; Berendes, Sima; Burke, Kelly; Mngqibisa, Rosie; Kanyama, Cecelia; Kayoyo, Virginia; Samaneka, Wadzanai P.; Chisada, Anthony; Faesen, Sharla; Chariyalertsak, Suwat; Santos, Breno; Lira, Rita Alves; Joglekar, Anjali A.; Rosa, Alberto La; Infante, Rosa; Jain, Mamta; Petersen, Tianna; Godbole, Sheela; Dhayarkar, Sampada; Feinberg, Judith; Baer, Jenifer; Pollard, Richard B.; Asmuth, David; Gangakhedkar, Raman R; Gaikwad, Asmita; Ray, M. Graham; Basler, Cathi; Para, Michael F.; Watson, Kathy J.; Taiwo, Babafemi; McGregor, Donna; Balfour, Henry H.; Mullan, Beth; Kim, Ge-Youl; Klebert, Michael K.; Cox, Gary Matthew; Silberman, Martha; Mildvan, Donna; Revuelta, Manuel; Tashima, Karen T.; Patterson, Helen; Geiseler, P. Jan; Santos, Bartolo; Daar, Eric S; Lopez, Ruben; Frarey, Laurie; Currin, David; Haas, David H.; Bailey, Vicki L.; Tebas, Pablo; Zifchak, Larisa; Noel-Connor, Jolene; Torres, Madeline; Sha, Beverly E.; Fritsche, Janice M.; Cespedes, Michelle; Forcht, Janet; O'Brien, William A.; Mogridge, Cheryl; Hurley, Christine; Corales, Roberto; Palmer, Maria; Adams, Mary; Luque, Amneris; Lopez-Detres, Luis; Stroberg, Todd

2012-01-01

Background Antiretroviral regimens with simplified dosing and better safety are needed to maximize the efficiency of antiretroviral delivery in resource-limited settings. We investigated the efficacy and safety of antiretroviral regimens with once-daily compared to twice-daily dosing in diverse areas of the world. Methods and Findings 1,571 HIV-1-infected persons (47% women) from nine countries in four continents were assigned with equal probability to open-label antiretroviral therapy with efavirenz plus lamivudine-zidovudine (EFV+3TC-ZDV), atazanavir plus didanosine-EC plus emtricitabine (ATV+DDI+FTC), or efavirenz plus emtricitabine-tenofovir-disoproxil fumarate (DF) (EFV+FTC-TDF). ATV+DDI+FTC and EFV+FTC-TDF were hypothesized to be non-inferior to EFV+3TC-ZDV if the upper one-sided 95% confidence bound for the hazard ratio (HR) was ≤1.35 when 30% of participants had treatment failure. An independent monitoring board recommended stopping study follow-up prior to accumulation of 472 treatment failures. Comparing EFV+FTC-TDF to EFV+3TC-ZDV, during a median 184 wk of follow-up there were 95 treatment failures (18%) among 526 participants versus 98 failures among 519 participants (19%; HR 0.95, 95% CI 0.72–1.27; p = 0.74). Safety endpoints occurred in 243 (46%) participants assigned to EFV+FTC-TDF versus 313 (60%) assigned to EFV+3TC-ZDV (HR 0.64, CI 0.54–0.76; p<0.001) and there was a significant interaction between sex and regimen safety (HR 0.50, CI 0.39–0.64 for women; HR 0.79, CI 0.62–1.00 for men; p = 0.01). Comparing ATV+DDI+FTC to EFV+3TC-ZDV, during a median follow-up of 81 wk there were 108 failures (21%) among 526 participants assigned to ATV+DDI+FTC and 76 (15%) among 519 participants assigned to EFV+3TC-ZDV (HR 1.51, CI 1.12–2.04; p = 0.007). Conclusion EFV+FTC-TDF had similar high efficacy compared to EFV+3TC-ZDV in this trial population, recruited in diverse multinational settings. Superior safety, especially in HIV-1-infected women, and once-daily dosing of EFV+FTC-TDF are advantageous for use of this regimen for initial treatment of HIV-1 infection in resource-limited countries. ATV+DDI+FTC had inferior efficacy and is not recommended as an initial antiretroviral regimen. Trial Registration www.ClinicalTrials.gov NCT00084136 Please see later in the article for the Editors' Summary. PMID:22936892

Alert dwell time: introduction of a measure to evaluate interruptive clinical decision support alerts

PubMed Central

McDaniel, Robert B; Burlison, Jonathan D; Baker, Donald K; Hasan, Murad; Robertson, Jennifer; Hartford, Christine; Howard, Scott C; Sablauer, Andras

2016-01-01

Metrics for evaluating interruptive prescribing alerts have many limitations. Additional methods are needed to identify opportunities to improve alerting systems and prevent alert fatigue. In this study, the authors determined whether alert dwell time—the time elapsed from when an interruptive alert is generated to when it is dismissed—could be calculated by using historical alert data from log files. Drug–drug interaction (DDI) alerts from 3 years of electronic health record data were queried. Alert dwell time was calculated for 25,965 alerts, including 777 unique DDIs. The median alert dwell time was 8 s (range, 1–4913 s). Resident physicians had longer median alert dwell times than other prescribers (P < .001). The 10 most frequent DDI alerts (n = 8759 alerts) had shorter median dwell times than alerts that only occurred once (P < .001). This metric can be used in future research to evaluate the effectiveness and efficiency of interruptive prescribing alerts. PMID:26499101

Recommendations for selecting drug-drug interactions for clinical decision support.

PubMed

Tilson, Hugh; Hines, Lisa E; McEvoy, Gerald; Weinstein, David M; Hansten, Philip D; Matuszewski, Karl; le Comte, Marianne; Higby-Baker, Stefanie; Hanlon, Joseph T; Pezzullo, Lynn; Vieson, Kathleen; Helwig, Amy L; Huang, Shiew-Mei; Perre, Anthony; Bates, David W; Poikonen, John; Wittie, Michael A; Grizzle, Amy J; Brown, Mary; Malone, Daniel C

2016-04-15

Recommendations for including drug-drug interactions (DDIs) in clinical decision support (CDS) are presented. A conference series was conducted to improve CDS for DDIs. A work group consisting of 20 experts in pharmacology, drug information, and CDS from academia, government agencies, health information vendors, and healthcare organizations was convened to address (1) the process to use for developing and maintaining a standard set of DDIs, (2) the information that should be included in a knowledge base of standard DDIs, (3) whether a list of contraindicated drug pairs can or should be established, and (4) how to more intelligently filter DDI alerts. We recommend a transparent, systematic, and evidence-driven process with graded recommendations by a consensus panel of experts and oversight by a national organization. We outline key DDI information needed to help guide clinician decision-making. We recommend judicious classification of DDIs as contraindicated and more research to identify methods to safely reduce repetitive and less-relevant alerts. An expert panel with a centralized organizer or convener should be established to develop and maintain a standard set of DDIs for CDS in the United States. The process should be evidence driven, transparent, and systematic, with feedback from multiple stakeholders for continuous improvement. The scope of the expert panel's work should be carefully managed to ensure that the process is sustainable. Support for research to improve DDI alerting in the future is also needed. Adoption of these steps may lead to consistent and clinically relevant content for interruptive DDIs, thus reducing alert fatigue and improving patient safety. Copyright © 2016 by the American Society of Health-System Pharmacists, Inc. All rights reserved.

Insecurity of Detector-Device-Independent Quantum Key Distribution.

PubMed

Sajeed, Shihan; Huang, Anqi; Sun, Shihai; Xu, Feihu; Makarov, Vadim; Curty, Marcos

2016-12-16

Detector-device-independent quantum key distribution (DDI-QKD) held the promise of being robust to detector side channels, a major security loophole in quantum key distribution (QKD) implementations. In contrast to what has been claimed, however, we demonstrate that the security of DDI-QKD is not based on postselected entanglement, and we introduce various eavesdropping strategies that show that DDI-QKD is in fact insecure against detector side-channel attacks as well as against other attacks that exploit devices' imperfections of the receiver. Our attacks are valid even when the QKD apparatuses are built by the legitimate users of the system themselves, and thus, free of malicious modifications, which is a key assumption in DDI-QKD.

Characterization of the mechanism of drug-drug interactions from PubMed using MeSH terms.

PubMed

Lu, Yin; Figler, Bryan; Huang, Hong; Tu, Yi-Cheng; Wang, Ju; Cheng, Feng

2017-01-01

Identifying drug-drug interaction (DDI) is an important topic for the development of safe pharmaceutical drugs and for the optimization of multidrug regimens for complex diseases such as cancer and HIV. There have been about 150,000 publications on DDIs in PubMed, which is a great resource for DDI studies. In this paper, we introduced an automatic computational method for the systematic analysis of the mechanism of DDIs using MeSH (Medical Subject Headings) terms from PubMed literature. MeSH term is a controlled vocabulary thesaurus developed by the National Library of Medicine for indexing and annotating articles. Our method can effectively identify DDI-relevant MeSH terms such as drugs, proteins and phenomena with high accuracy. The connections among these MeSH terms were investigated by using co-occurrence heatmaps and social network analysis. Our approach can be used to visualize relationships of DDI terms, which has the potential to help users better understand DDIs. As the volume of PubMed records increases, our method for automatic analysis of DDIs from the PubMed database will become more accurate.

Alteration of Hemostatic Parameters in Patients with Different Levels of Subclinical Hypothyroidism and the Effect of L-thyroxine Treatment.

PubMed

Gao, Fang; Wang, Guangya; Xu, Jinxiu

2017-01-01

Subclinical hypothyroidism (SH) is associated with hypercoagulability and hypofibrinolysis. The objective of this study was to assess the effect of L-thyroxine (L-T4) treatment and to evaluate changes in the hemostatic abnormalities of patients with varying severities of SH. We measured tissue plasminogen activator (t-PA), plasminogen activator inhibitor-1 (PAI-1), D-dimer (DDI), fibrinogen (FIB), platelet counts (PLT), mean platelet volume (MPV), platelet distribution width (PDW), activated partial thromboplastin time (APTT), and prothrombin time (PT) in 149 female subjects. The prospective study included 54 patients in the control group, 53 patients with 4.2 μIU/mL

Piloting social engagement on a federal agency-administered Facebook page.

PubMed

Chiu, Kimberly; Wagner, Lindsay; Choe, Lena; Chew, Catherine; Kremzner, Mary

2016-01-01

To evaluate the impact of a Federal drug information center initiating engagement with stakeholders on a Facebook Page administered by a Federal Agency. The U.S. Food and Drug Administration (FDA) Facebook page from July 21, 2014, to October 18, 2014. FDA's Division of Drug Information (DDI) in the Center for Drug Evaluation and Research (CDER) Office of Communications serves as a federal drug information center providing timely, accurate, and useful information on CDER initiatives and CDER-regulated products. We report a 90-day (July 21 to October 18, 2014) pilot during which DDI pharmacists monitored and moderated comments received on FDA's Facebook page to identify those warranting a reply. Once identified, DDI pharmacists replied within 2 business days. Impact was measured by comparing the average number of Likes, Shares, and Reach for Facebook posts before and after the pilot. Additional metrics collected include the number of DDI replies provided to stakeholders' comments and the number of DDI replies provided on time (within 2 business days). During the pilot, DDI contributed 14 posts. On average, each post reached 23,582 more individuals (an increase of 187% compared with pre-pilot posts). On average, each post also received 463 more Likes (450% increase) and 130 more Shares (271% increase). DDI pharmacists replied to 3% (121/3994) and hid 0.58% (23/3994) of Facebook comments received during the 90-day period. All actions were taken within 2 business days. Initiating social engagement had a positive impact on FDA's Facebook page. Published by Elsevier Inc.

An evaluation of the completeness of drug-drug interaction-related information in package inserts.

PubMed

Ng, Giok Qin; Sklar, Grant Edward; Chng, Hui Ting

2017-02-01

The project aimed to evaluate the completeness of drug-drug interaction (DDI)-related information in package inserts (PIs) and develop a systematic approach to conduct the evaluation. DDI-related information in the branded PIs of statins, macrolides, protease inhibitors and selected drugs of narrow therapeutic index (DNTI) were evaluated against the criteria distilled from the Food and Drug Administration (FDA) labelling recommendation guidance document. Decision trees were crafted and employed in the evaluation process. Scores were computed to give each PI an overall completeness score and individual criterion completeness score. The Kruskal-Wallis test and Dunn's multiple comparison test were used to assess the differences in the completeness scores. The mean overall completeness score of the 21 PIs was 35.7 ± 13.4 % (range 12.2-62 %). Eight out of the 11 individual evaluation criterion had a mean completeness score below 50 %. A subclass analysis conducted revealed that PIs from the different drug classes differed in the type of DDI-related information, such that they are more complete or less complete. The completeness score of DDI-related information in the PIs varied extensively amongst and within drug classes. A consensus between the authorities and drug companies on the type and quality of DDI-related information to be included could improve their completeness in PIs and make PIs a valuable source of DDI reference. Decision trees, albeit not validated yet, lay the groundwork for a valuable tool to evaluate DDI-related or other drug information.

Effects of Passage Number and Differentiation Protocol on the Generation of Dopaminergic Neurons from Rat Bone Marrow-Derived Mesenchymal Stem Cells.

PubMed

Shall, Gabrielle; Menosky, Megan; Decker, Sarah; Nethala, Priya; Welchko, Ryan; Leveque, Xavier; Lu, Ming; Sandstrom, Michael; Hochgeschwender, Ute; Rossignol, Julien; Dunbar, Gary

2018-03-02

Multiple studies have demonstrated the ability of mesenchymal stem cells (MSCs) to differentiate into dopamine-producing cells, in vitro and in vivo, indicating their potential to be used in the treatment of Parkinson's disease (PD). However, there are discrepancies among studies regarding the optimal time (i.e., passage number) and method for dopaminergic induction, in vitro. In the current study, we compared the ability of early (P4) and later (P40) passaged bone marrow-derived MSCs to differentiate into dopaminergic neurons using two growth-factor-based approaches. A direct dopaminergic induction (DDI) was used to directly convert MSCs into dopaminergic neurons, and an indirect dopaminergic induction (IDI) was used to direct MSCs toward a neuronal lineage prior to terminal dopaminergic differentiation. Results indicate that both early and later passaged MSCs exhibited positive expression of neuronal and dopaminergic markers following either the DDI or IDI protocols. Additionally, both early and later passaged MSCs released dopamine and exhibited spontaneous neuronal activity following either the DDI or IDI. Still, P4 MSCs exhibited significantly higher spiking and bursting frequencies as compared to P40 MSCs. Findings from this study provide evidence that early passaged MSCs, which have undergone the DDI, are more efficient at generating dopaminergic-like cells in vitro, as compared to later passaged MSCs or MSCs that have undergone the IDI.

Maintaining a low viral load with Nevirapine?

PubMed

1998-12-01

A study called INCAS enrolled 150 treatment-naive subjects. Half of the subjects had CD4+ counts of 370 and a viral load of about 32,000 copies. Subjects were divided into groups that received AZT and Nevirapine, ddI and Nevirapine, or AZT with ddI and Nevirapine. Researchers monitored the subjects for 1 year. Results indicated that subjects who received the triple drug combination had fewer complications and infections.

Harnessing the internet cloud for managing drug interactions with chemotherapy regimens in patients with cancer suffering from depression.

PubMed

Yap, Kevin Yi-Lwern; Ho, Yasmin Xiu Xiu; Chui, Wai Keung; Chan, Alexandre

2010-11-01

Concomitant use of anticancer drugs (ACDs) and antidepressants (ADs) in the treatment of depression in patients with cancer may result in potentially harmful drug-drug interactions (DDIs). It is crucial that clinicians make timely, accurate, safe and effective decisions regarding drug therapies in patients. The ubiquitous nature of the internet or "cloud" has enabled easy dissemination of DDI information, but there is currently no database dedicated to allow searching of ACD interactions by chemotherapy regimens. We describe the implementation of an AD interaction module to a previously published oncology-specific DDI database for clinicians which focuses on ACDs, single-agent and multiple-agent chemotherapy regimens. Drug- and DDI-related information were collated from drug information handbooks, databases, package inserts, and published literature from PubMed, Scopus and Science Direct. Web documents were constructed using Adobe software and programming scripts, and mounted on a domain served from the internet cloud. OncoRx is an oncology-specific DDI database whose structure is designed around all the major classes of ACDs and their frequently prescribed chemotherapy regimens. There are 117 ACDs and 256 regimens in OncoRx, and it can detect over 1 500 interactions with 21 ADs. Clinicians are provided with the pharmacokinetic parameters of the drugs, information on the regimens and details of the detected DDIs during an interaction search. OncoRx is the first database of its kind which allows detection of ACD and chemotherapy regimen interactions with ADs. This tool will assist clinicians in improving clinical response and reducing adverse effects based on the therapeutic and toxicity profiles of the drugs.

Surface amplification of pencil graphite electrode with polypyrrole and reduced graphene oxide for fabrication of a guanine/adenine DNA based electrochemical biosensors for determination of didanosine anticancer drug

NASA Astrophysics Data System (ADS)

Karimi-Maleh, Hassan; Bananezhad, Asma; Ganjali, Mohammad R.; Norouzi, Parviz; Sadrnia, Abdolhossein

2018-05-01

Didanosine is nucleoside analog reverse transcriptase inhibitors with many side effects such as nausea and vomiting, stomach pain, tingling, burning and numbness and determination of this drug is very important in biological samples. This paper presents a DNA biosensor for determination of didanosine (DDI) in pharmaceutical samples. A pencil graphite electrode modified with conductive materials such as polypyrrole (PPy) and reduced graphene oxide (rGO) (PGE/PPy/rGO) was used for this goal. The double-stranded DNA was successfully immobilized on PGE/PPy/rGO. The PGE/PPy/rGO was characterized by microscopic and electrochemical methods. Then, the interaction of DDI with DNA was identified by decreases in the oxidation currents of guanine and adenine by differential pulse voltammetric (DPV) method. The dynamic range of DDI identified in the range of 0.02-50.0 μM and this electrode provided a low limit of detection (LOD = 8.0 nM) for DDI. The PGE/PPy/rGO loaded with ds-DNA was utilized for the measurement of DDI in real samples and obtained data were compared with HPLC method. The statistical tests such as F-test and t-test were used for confirming ability of PGE/PPy/rGO loaded with ds-DNA for analysis of DDI in real samples.

Target mediated drug disposition with drug–drug interaction, Part II: competitive and uncompetitive cases

PubMed Central

Jusko, William J.; Schropp, Johannes

2017-01-01

We present competitive and uncompetitive drug–drug interaction (DDI) with target mediated drug disposition (TMDD) equations and investigate their pharmacokinetic DDI properties. For application of TMDD models, quasi-equilibrium (QE) or quasi-steady state (QSS) approximations are necessary to reduce the number of parameters. To realize those approximations of DDI TMDD models, we derive an ordinary differential equation (ODE) representation formulated in free concentration and free receptor variables. This ODE formulation can be straightforward implemented in typical PKPD software without solving any non-linear equation system arising from the QE or QSS approximation of the rapid binding assumptions. This manuscript is the second in a series to introduce and investigate DDI TMDD models and to apply the QE or QSS approximation. PMID:28074396

Differences in susceptibility of mouse strains to tetrodotoxin.

PubMed

Suzuki, Hodaka

2016-09-01

The mouse bioassay for tetrodotoxin has been used for many years in Japan. To the best of our knowledge, however, there have only been a few reports that have specifically investigated differences in susceptibility to tetrodotoxin among mouse strains. In this study, we investigated the response of various mouse strains to tetrodotoxin. Tetrodotoxin solution was injected intraperitoneally into male mice of 5 inbred strains (A/J, BALB/c, C3H/He, C57BL/6, and DBA/2) and male and female mice of 2 non-inbred strains (ddY and ICR). Significant differences in susceptibility to tetrodotoxin were found among the mouse strains tested. In comparison to the ddY male mice, which are designated to be used in the Japanese reference method, the 5 inbred strains of mice tested were significantly more resistant to tetrodotoxin. However, no significant differences in tetrodotoxin susceptibility were observed between ddY male and female mice or between ddY male mice and ICR male and female mice. These results indicate that the users of the mouse bioassay should pay attention to differences in mouse strain in susceptibility to tetrodotoxin. Copyright © 2016 Elsevier Ltd. All rights reserved.

Comparison of the inhibition potentials of icotinib and erlotinib against human UDP-glucuronosyltransferase 1A1.

PubMed

Cheng, Xuewei; Lv, Xia; Qu, Hengyan; Li, Dandan; Hu, Mengmeng; Guo, Wenzhi; Ge, Guangbo; Dong, Ruihua

2017-11-01

UDP-glucuronosyltransferase 1A1 (UGT1A1) plays a key role in detoxification of many potentially harmful compounds and drugs. UGT1A1 inhibition may bring risks of drug-drug interactions (DDIs), hyperbilirubinemia and drug-induced liver injury. This study aimed to investigate and compare the inhibitory effects of icotinib and erlotinib against UGT1A1, as well as to evaluate their potential DDI risks via UGT1A1 inhibition. The results demonstrated that both icotinib and erlotinib are UGT1A1 inhibitors, but the inhibitory effect of icotinib on UGT1A1 is weaker than that of erlotinib. The IC 50 values of icotinib and erlotinib against UGT1A1-mediated NCHN- O -glucuronidation in human liver microsomes (HLMs) were 5.15 and 0.68 μmol/L, respectively. Inhibition kinetic analyses demonstrated that both icotinib and erlotinib were non-competitive inhibitors against UGT1A1-mediated glucuronidation of NCHN in HLMs, with the K i values of 8.55 and 1.23 μmol/L, respectively. Furthermore, their potential DDI risks via UGT1A1 inhibition were quantitatively predicted by the ratio of the areas under the concentration-time curve (AUC) of NCHN. These findings are helpful for the medicinal chemists to design and develop next generation tyrosine kinase inhibitors with improved safety, as well as to guide reasonable applications of icotinib and erlotinib in clinic, especially for avoiding their potential DDI risks via UGT1A1 inhibition.

Evaluation of a potential transporter-mediated drug interaction between rosuvastatin and pradigastat, a novel DGAT-1 inhibitor.

PubMed

Kulmatycki, Kenneth; Hanna, Imad; Meyers, Dan; Salunke, Atish; Movva, Aishwarya; Majumdar, Tapan; Natrillo, Adrienne; Vapurcuyan, Arpine; Rebello, Sam; Sunkara, Gangadhar; Chen, Jin

2015-05-01

An in vitro drugdrug interaction (DDI) study was performed to assess the potential for pradigastat to inhibit breast cancer resistance protein (BCRP), organic anion-transporting polypeptide (OATP), and organic anion transporter 3 (OAT3) transport activities. To understand the relevance of these in vitro findings, a clinical pharmacokinetic DDI study using rosuvastatin as a BCRP, OATP, and OAT3 probe substrate was conducted. The study used cell lines that stably expressed or over-expressed the respective transporters. The clinical study was an open-label, single sequence study where subjects (n = 36) received pradigastat (100 mg once daily x 3 days thereafter 40 mg once daily) and rosuvastatin (10 mg once daily), alone and in combination. Pradigastat inhibited BCRP-mediated efflux activity in a dose-dependent fashion in a BCRP over-expressing human ovarian cancer cell line with an IC(50) value of 5 μM. Similarly, pradigastat inhibited OATP1B1, OATP1B3 (estradiol 17β glucuronide transport), and OAT3 (estrone 3 sulfate transport) activity in a concentrationdependent manner with estimated IC(50) values of 1.66 ± 0.95 μM, 3.34 ± 0.64 μM, and 0.973 ± 0.11 μM, respectively. In the presence of steady state pradigastat concentrations, AUC(τ, ss) of rosuvastatin was unchanged and its Cmax,ss decreased by 14% (5.30 and 4.61 ng/mL when administered alone and coadministered with pradigastat, respectively). Pradigastat AUC(τ, ss) and C(max, ss) were unchanged when coadministered with rosuvastatin at steady state. Both rosuvastatin and pradigastat were well tolerated. These data indicate no clinically relevant pharmacokinetic interaction between pradigastat and rosuvastatin.

The burden and management of cytochrome P450 2D6 (CYP2D6)-mediated drug-drug interaction (DDI): co-medication of metoprolol and paroxetine or fluoxetine in the elderly.

PubMed

Bahar, Muh Akbar; Hak, Eelko; Bos, Jens H J; Borgsteede, Sander D; Wilffert, Bob

2017-07-01

Metoprolol and paroxetine/fluoxetine are inevitably co-prescribed because cardiovascular disorders and depression often coexist in the elderly. This leads to CYP2D6-mediated drug-drug interactions (DDI). Because systematic evaluations are lacking, we assessed the burden of metoprolol-paroxetine/fluoxetine interaction in the elderly and how these interactions are managed in Dutch community pharmacies. Dispensing data were collected from the University of Groningen pharmacy database (IADB.nl, 1999-2014) for elderly patients (≥60 years) starting beta-blockers and/or antidepressants. Based on the two main DDI alert systems (G-Standard and Pharmabase), incidences were divided between signalled (metoprolol-fluoxetine/paroxetine) and not-signalled (metoprolol-alternative antidepressants and alternative beta-blockers-paroxetine/fluoxetine) combinations. Incident users were defined as patients starting at least one signalled or a non-signalled combination. G-Standard signalled throughout the study period, whereas Pharmabase stopped after 2005. A total of 1763 patients had 2039 metoprolol-paroxetine/fluoxetine co-prescriptions, despite DDI alert systems, and about 57.3% were signalled. The number of metoprolol-alternative antidepressant combinations (incidences = 3150) was higher than alternative beta-blocker-paroxetine/fluoxetine combinations (incidences = 1872). Metoprolol users are more likely to be co-medicated with an alternative antidepressant (incidences = 2320) than paroxetine/fluoxetine users (incidences = 1232) are. The number of paroxetine/fluoxetine users co-prescribed with alternative beta-blockers was comparable to those co-medicated with metoprolol (about 50%). Less than 5% of patients received a substitute therapy after using metoprolol-paroxetine/fluoxetine. Most of the metoprolol users (90%) received a low dose (mean DDD = 0.47) regardless whether they were prescribed paroxetine/fluoxetine. Despite the signalling software, metoprolol-paroxetine/fluoxetine combinations are still observed in the elderly population. The clinical impact of these interactions needs further investigation. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

Utilizing Structures of CYP2D6 and BACE1 Complexes To Reduce Risk of Drug–Drug Interactions with a Novel Series of Centrally Efficacious BACE1 Inhibitors

PubMed Central

2016-01-01

In recent years, the first generation of β-secretase (BACE1) inhibitors advanced into clinical development for the treatment of Alzheimer’s disease (AD). However, the alignment of drug-like properties and selectivity remains a major challenge. Herein, we describe the discovery of a novel class of potent, low clearance, CNS penetrant BACE1 inhibitors represented by thioamidine 5. Further profiling suggested that a high fraction of the metabolism (>95%) was due to CYP2D6, increasing the potential risk for victim-based drug–drug interactions (DDI) and variable exposure in the clinic due to the polymorphic nature of this enzyme. To guide future design, we solved crystal structures of CYP2D6 complexes with substrate 5 and its corresponding metabolic product pyrazole 6, which provided insight into the binding mode and movements between substrate/inhibitor complexes. Guided by the BACE1 and CYP2D6 crystal structures, we designed and synthesized analogues with reduced risk for DDI, central efficacy, and improved hERG therapeutic margins. PMID:25781223

Current use of anti-HIV drugs in AIDS.

PubMed

Clumeck, N

1993-07-01

Since 1987 major advances have been made in our understanding of the pathogenesis of infection and the possible inhibition of the HIV virus. Various drugs targeted to the different steps of viral replication have been selected, but drugs such as soluble CD4 or dextran derivatives aimed to inhibit or interfere with the GP120-CD4 attachment step have shown little or no clinical benefit. Protease inhibitors or interferons acting at the post-transcriptional level are currently under phase I to II investigation. The only group of compounds clinically active belong to the nucleosides analogues that act as DNA chain terminators and by inhibiting viral reverse transcriptase. Zidovudine (AZT), didanosine (ddI) and dideoxycytidine (ddC) have been extensively studied, and used on a large clinical scale. Stavudine (D4T), deoxyfluorothymidine (FLT) and 3'thiacytidine (3TC) are entering phase I-II studies. Being the first nucleoside analogue discovered and used since early 1985, zidovudine remains the gold standard of anti-HIV therapy. Zidovudine is indicated at a dosage varying between 500 and 1000 mg in patients with AIDS and ARC, in asymptomatic patients with CD4 < 200/mm3 and in asymptomatic patients with CD4 between 200 and 500 cells/mm3 with a rapid decrease of CD4 cell count or a positive P24 circulating antigen. There is as yet no consensus concerning patients with more than 500 cell/mm3. ddI and ddC are currently indicated for patients intolerant to AZT or in those who have not responded (clinically or biologically) to AZT. Emergence of resistance to AZT has been reported in 30 to 80% of patients at various stages of the disease and after six to nine months of therapy.(ABSTRACT TRUNCATED AT 250 WORDS)

An investigation of automatic exposure control calibration for chest imaging with a computed radiography system.

PubMed

Moore, C S; Wood, T J; Avery, G; Balcam, S; Needler, L; Beavis, A W; Saunderson, J R

2014-05-07

The purpose of this study was to examine the use of three physical image quality metrics in the calibration of an automatic exposure control (AEC) device for chest radiography with a computed radiography (CR) imaging system. The metrics assessed were signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR) and mean effective noise equivalent quanta (eNEQm), all measured using a uniform chest phantom. Subsequent calibration curves were derived to ensure each metric was held constant across the tube voltage range. Each curve was assessed for its clinical appropriateness by generating computer simulated chest images with correct detector air kermas for each tube voltage, and grading these against reference images which were reconstructed at detector air kermas correct for the constant detector dose indicator (DDI) curve currently programmed into the AEC device. All simulated chest images contained clinically realistic projected anatomy and anatomical noise and were scored by experienced image evaluators. Constant DDI and CNR curves do not appear to provide optimized performance across the diagnostic energy range. Conversely, constant eNEQm and SNR do appear to provide optimized performance, with the latter being the preferred calibration metric given as it is easier to measure in practice. Medical physicists may use the SNR image quality metric described here when setting up and optimizing AEC devices for chest radiography CR systems with a degree of confidence that resulting clinical image quality will be adequate for the required clinical task. However, this must be done with close cooperation of expert image evaluators, to ensure appropriate levels of detector air kerma.

An investigation of automatic exposure control calibration for chest imaging with a computed radiography system

NASA Astrophysics Data System (ADS)

Moore, C. S.; Wood, T. J.; Avery, G.; Balcam, S.; Needler, L.; Beavis, A. W.; Saunderson, J. R.

2014-05-01

The purpose of this study was to examine the use of three physical image quality metrics in the calibration of an automatic exposure control (AEC) device for chest radiography with a computed radiography (CR) imaging system. The metrics assessed were signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR) and mean effective noise equivalent quanta (eNEQm), all measured using a uniform chest phantom. Subsequent calibration curves were derived to ensure each metric was held constant across the tube voltage range. Each curve was assessed for its clinical appropriateness by generating computer simulated chest images with correct detector air kermas for each tube voltage, and grading these against reference images which were reconstructed at detector air kermas correct for the constant detector dose indicator (DDI) curve currently programmed into the AEC device. All simulated chest images contained clinically realistic projected anatomy and anatomical noise and were scored by experienced image evaluators. Constant DDI and CNR curves do not appear to provide optimized performance across the diagnostic energy range. Conversely, constant eNEQm and SNR do appear to provide optimized performance, with the latter being the preferred calibration metric given as it is easier to measure in practice. Medical physicists may use the SNR image quality metric described here when setting up and optimizing AEC devices for chest radiography CR systems with a degree of confidence that resulting clinical image quality will be adequate for the required clinical task. However, this must be done with close cooperation of expert image evaluators, to ensure appropriate levels of detector air kerma.

Nootropic nefiracetam inhibits proconvulsant action of peripheral-type benzodiazepines in epileptic mutant EL mice.

PubMed

Nakamoto, Yurie; Shiotani, Tadashi; Watabe, Shigeo; Nabeshima, Toshitaka; Yoshii, Mitsunobu

2004-10-01

Piracetam and structurally related nootropics are known to potentiate the anticonvulsant effects of antiepileptic drugs. It remains to be seen, however, whether these nootropics inhibit proconvulsant actions of many toxic agents including Ro 5-4864, a specific agonist for peripheral-type benzodiazepine receptors (PBR). The present study was designed to address this issue using EL mice, an animal model of epilepsy. In behavioral pharmacological experiments, EL mice were highly susceptible to convulsions induced by Ro 5-4864 (i.p.) in comparison with nonepileptic DDY mice. Nefiracetam administered orally to EL mice inhibited spontaneous seizures. In DDY mice, convulsions induced by Ro 5-4864 were prevented by nefiracetam when administered by i.v. injection. Aniracetam (i.v.) was partially effective, but piracetam and oxiracetam were ineffective as anticonvulsants. Binding assay for brain tissues revealed a higher density of mitochondrial PBR in EL mice compared with DDY mice. Binding of the PBR ligands Ro 5-4864 to either EL or DDY mouse brain was inhibited by micromolar concentrations of these nootropic agents in the sequence of nefiracetam > aniracetam > oxiracetam, piracetam. This rank order is identical to potency as anticonvulsants. These data suggest that nefiracetam may prevent toxic effects of PBR agonists through interacting with PBR.

Specific, sensitive, and rapid assay for human immunodeficiency virus type 1 pol mutations associated with resistance to zidovudine and didanosine.

PubMed Central

Frenkel, L M; Wagner, L E; Atwood, S M; Cummins, T J; Dewhurst, S

1995-01-01

The effectiveness of antiretroviral therapy may be limited by the development of human immunodeficiency virus type 1 (HIV-1) resistance. Monitoring for resistance will perhaps allow changes in therapy prior to deterioration in the patient's clinical or immunologic status. Our objective was to develop a rapid, specific, and sensitive genotypic assay for HIV-1 resistance to zidovudine (ZDV) and didanosine (ddI) which is simple to perform. In our assay the DNA of HIV-1 pol was amplified by PCR using two sets of nested oligonucleotide primers. Mutations of reverse transcriptase (RT) encoding amino acids (aa) 74 and 41, 70, and 215 which have been associated with HIV-1 resistance to ddI and ZDV, respectively, were detected with a ligase detection reaction (LDR) and indicated colorimetrically. The RT genotypes of 35 patient specimens (140 codons) blindly assessed for these mutations were in agreement by PCR-LDR and by dideoxynucleotide sequencing. To evaluate the limits of the assay, other specimens with mutations close to the ligation site were evaluated by PCR-LDR. The assay was sensitive and specific for all specimens except when mutations occurred within 2 bases on either side of the ligation site. In summary, this PCR-LDR assay specifically, sensitively, and rapidly detected pol mutations (RT aa 74, 41, 70, and 215) associated with HIV-1 resistance to ddI and ZDV. PMID:7714190

Safety evaluation of diverging diamond interchanges in Missouri.

DOT National Transportation Integrated Search

2015-01-01

The Diverging Diamond Interchange (DDI) has gained in popularity in the United States during the last decade. The : operational benefits and lower costs of retrofitting a conventional diamond with a DDI have contributed to its increased use. : Existi...

UDOT diverging diamond interchange (DDI) observations and experience.

DOT National Transportation Integrated Search

2012-04-01

This report presents the results of a functionality evaluation, by the I-15 Utah County Corridor Expansion (CORE) traffic team, of the first Diverging Diamond Interchange (DDI) in Utah, located at the intersection of American Fork Main Street (Pionee...

Antisocial and seizure susceptibility phenotypes in an animal model of epilepsy are normalized by impairment of brain corticotropin-releasing factor.

PubMed

Turner, Laura H; Lim, Chen E; Heinrichs, Stephen C

2007-02-01

Social interaction phenotyping is an unexplored niche in animal modeling of epilepsy despite the sensitivity of affiliative behaviors to emotionality and stress, which are known seizure triggers. Thus, the present studies examined the social phenotype of seizure-susceptible El and nonsusceptible ddY strains both in untreated animals and following preexposure to a handling stressor. The second aim of the present studies was to evaluate the dependence of sociability in El mice on the proconvulsive, stress neuropeptide corticotropin-releasing factor (CRF) using CRF-SAP, a conjugate of CRF and the toxin saporin, which selectively reduced CRF peptide levels in the basolateral amygdala of El mice. El mice exhibited lower social investigation times than ddY counterparts, whereas central administration of CRF-SAP normalized social investigation times relative to ddY controls. Moreover, handling-induced seizures in El mice were reduced by 50% following treatment with CRF-SAP relative to saporin alone-injected El controls. The results of this study suggest that tonically activated CRF systems in the El mouse brain suppress affiliative behavior and facilitate evoked seizures.

Comparison of three commercial knowledge bases for detection of drug-drug interactions in clinical decision support.

PubMed

Fung, Kin Wah; Kapusnik-Uner, Joan; Cunningham, Jean; Higby-Baker, Stefanie; Bodenreider, Olivier

2017-07-01

To compare 3 commercial knowledge bases (KBs) used for detection and avoidance of potential drug-drug interactions (DDIs) in clinical practice. Drugs in the DDI tables from First DataBank (FDB), Micromedex, and Multum were mapped to RxNorm. The KBs were compared at the clinical drug, ingredient, and DDI rule levels. The KBs were evaluated against a reference list of highly significant DDIs from the Office of the National Coordinator for Health Information Technology (ONC). The KBs and the ONC list were applied to a prescription data set to simulate their use in clinical decision support. The KBs contained 1.6 million (FDB), 4.5 million (Micromedex), and 4.8 million (Multum) clinical drug pairs. Altogether, there were 8.6 million unique pairs, of which 79% were found only in 1 KB and 5% in all 3 KBs. However, there was generally more agreement than disagreement in the severity rankings, especially in the contraindicated category. The KBs covered 99.8-99.9% of the alerts of the ONC list and would have generated 25 (FDB), 145 (Micromedex), and 84 (Multum) alerts per 1000 prescriptions. The commercial KBs differ considerably in size and quantity of alerts generated. There is less variability in severity ranking of DDIs than suggested by previous studies. All KBs provide very good coverage of the ONC list. More work is needed to standardize the editorial policies and evidence for inclusion of DDIs to reduce variation among knowledge sources and improve relevance. Some DDIs considered contraindicated in all 3 KBs might be possible candidates to add to the ONC list. Published by Oxford University Press on behalf of the American Medical Informatics Association 2017. This work is written by US Government employees and is in the public domain in the United States.

DIETARY DIVERSITY AND ITS RELATIONSHIP WITH NUTRITIONAL STATUS AMONG ADOLESCENTS AND ADULTS IN RURAL INDIA.

PubMed

Nithya, D J; Bhavani, R V

2018-05-01

SummaryDietary diversity is associated with household or individual food availability and intake of nutrients from different food groups and is an important component of nutritional outcome. This study examined the Nutrient Adequacy Ratio (NAR) and the Mean Adequacy Ratio (MAR) of three dietary diversity indices and their relationship with the nutritional status of adolescents and adults in rural regions of two states in India, Wardha district in Maharashtra and Koraput district in Odisha, in 2014. Individual dietary diversity was calculated using 24-hour diet recall (FS24hr) data and household dietary diversity was measured with food frequency data using Berry's index (DDI) and food scores (FSFFQ). The nutritional status of individuals was assessed using anthropometric indices. The diets in both locations were cereal dominated. It was observed that 51% of adolescent boys and 27% of adolescent girls had 'thinness' and stunting. The prevalence of undernutrition was higher among adult women (48%) than adult men (36%). The mean diversity indices were FS24hr of 8, DDI of 89-90 and FSFFQ of 64-66 in the two locations. The FS24hr was found to be positively correlated with the NAR of all nutrients while DDI and FSFFQ were correlated with seven and six nutrients, respectively. The DDI and FS24hr showed an association with MAR if the two locations were combined together. Sensitivity and specificity analysis showed that FS24hr gave more true positives than false positives and the area under the Receiver Operating Characteristic curve was 0.68, implying that this measure truly differentiates individuals having low dietary diversity with low MAR from those with low dietary diversity and a high MAR. All three measures of dietary diversity showed a linear association with the nutritional outcomes of adults, while in the adolescent group only DDI showed a relationship. It is concluded that 24-hour diet recall is a good measure for studying the relationship between dietary diversity and nutritional status in adults.

Biochemical and structural characterizations of two Dictyostelium cellobiohydrolases from the amoebozoa kingdom reveal a high level of conservation between distant phylogenetic trees of life

DOE PAGES

Hobdey, Sarah E.; Knott, Brandon C.; Momeni, Majid Haddad; ...

2016-04-01

Glycoside hydrolase family 7 (GH7) cellobiohydrolases (CBHs) are enzymes often employed in plant cell wall degradation across eukaryotic kingdoms of life, as they provide significant hydrolytic potential in cellulose turnover. To date, many fungal GH7 CBHs have been examined, yet many questions regarding structure-activity relationships in these important natural and commercial enzymes remain. Here, we present the crystal structures and a biochemical analysis of two GH7 CBHs from social amoeba: Dictyostelium discoideum Cel7A (DdiCel7A) and Dictyostelium purpureum Cel7A (DpuCel7A). DdiCel7A and DpuCel7A natively consist of a catalytic domain and do not exhibit a carbohydrate-binding module (CBM). The structures of DdiCel7Amore » and DpuCel7A, resolved to 2.1 Å and 2.7 Å, respectively, are homologous to those of other GH7 CBHs with an enclosed active-site tunnel. Two primary differences between the Dictyostelium CBHs and the archetypal model GH7 CBH, Trichoderma reesei Cel7A (TreCel7A), occur near the hydrolytic active site and the product-binding sites. To compare the activities of these enzymes with the activity of TreCel7A, the family 1 TreCel7A CBM and linker were added to the C terminus of each of the Dictyostelium enzymes, creating DdiCel7A CBM and DpuCel7A CBM, which were recombinantly expressed in T. reesei. DdiCel7A CBM and DpuCel7A CBM hydrolyzed Avicel, pretreated corn stover, and phosphoric acid-swollen cellulose as efficiently as TreCel7A when hydrolysis was compared at their temperature optima. The K i of cellobiose was significantly higher for DdiCel7A CBM and DpuCel7A CBM than for TreCel7A: 205, 130, and 29 μM, respectively. Finally, taken together, the present study highlights the remarkable degree of conservation of the activity of these key natural and industrial enzymes across quite distant phylogenetic trees of life.« less

Biochemical and structural characterizations of two Dictyostelium cellobiohydrolases from the amoebozoa kingdom reveal a high level of conservation between distant phylogenetic trees of life

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hobdey, Sarah E.; Knott, Brandon C.; Momeni, Majid Haddad

Glycoside hydrolase family 7 (GH7) cellobiohydrolases (CBHs) are enzymes often employed in plant cell wall degradation across eukaryotic kingdoms of life, as they provide significant hydrolytic potential in cellulose turnover. To date, many fungal GH7 CBHs have been examined, yet many questions regarding structure-activity relationships in these important natural and commercial enzymes remain. Here, we present the crystal structures and a biochemical analysis of two GH7 CBHs from social amoeba: Dictyostelium discoideum Cel7A (DdiCel7A) and Dictyostelium purpureum Cel7A (DpuCel7A). DdiCel7A and DpuCel7A natively consist of a catalytic domain and do not exhibit a carbohydrate-binding module (CBM). The structures of DdiCel7Amore » and DpuCel7A, resolved to 2.1 Å and 2.7 Å, respectively, are homologous to those of other GH7 CBHs with an enclosed active-site tunnel. Two primary differences between the Dictyostelium CBHs and the archetypal model GH7 CBH, Trichoderma reesei Cel7A (TreCel7A), occur near the hydrolytic active site and the product-binding sites. To compare the activities of these enzymes with the activity of TreCel7A, the family 1 TreCel7A CBM and linker were added to the C terminus of each of the Dictyostelium enzymes, creating DdiCel7A CBM and DpuCel7A CBM, which were recombinantly expressed in T. reesei. DdiCel7A CBM and DpuCel7A CBM hydrolyzed Avicel, pretreated corn stover, and phosphoric acid-swollen cellulose as efficiently as TreCel7A when hydrolysis was compared at their temperature optima. The K i of cellobiose was significantly higher for DdiCel7A CBM and DpuCel7A CBM than for TreCel7A: 205, 130, and 29 μM, respectively. Finally, taken together, the present study highlights the remarkable degree of conservation of the activity of these key natural and industrial enzymes across quite distant phylogenetic trees of life.« less

Exploring corridor operations in the vicinity of a diverging diamond interchange (DDI) : final report.

DOT National Transportation Integrated Search

2016-06-27

This research effort examined the corridor impacts of various signal timing and geometric strategies to improve the : operational challenges observed at DDIs. A microsimulation analysis was conducted using a calibrated and validated DDI : modeled aft...

Missouri's experience with a diverging diamond interchange : lessons learned.

DOT National Transportation Integrated Search

2010-05-01

The first DDI in the nation opened to traffic on June 21, 2009, in Springfield, Missouri. The interchange in : Springfield where the Kansas Expressway (MO-13) passes over I-44 is a huge success. A diverging diamond : interchange (DDI), sometimes refe...

Detector-device-independent quantum key distribution: Security analysis and fast implementation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Boaron, Alberto; Korzh, Boris; Houlmann, Raphael

One of the most pressing issues in quantum key distribution (QKD) is the problem of detector side-channel attacks. To overcome this problem, researchers proposed an elegant “time-reversal” QKD protocol called measurement-device-independent QKD (MDI-QKD), which is based on time-reversed entanglement swapping. But, MDI-QKD is more challenging to implement than standard point-to-point QKD. Recently, we proposed an intermediary QKD protocol called detector-device-independent QKD (DDI-QKD) in order to overcome the drawbacks of MDI-QKD, with the hope that it would eventually lead to a more efficient detector side-channel-free QKD system. We analyze the security of DDI-QKD and elucidate its security assumptions. We find thatmore » DDI-QKD is not equivalent to MDI-QKD, but its security can be demonstrated with reasonable assumptions. On the more practical side, we consider the feasibility of DDI-QKD and present a fast experimental demonstration (clocked at 625 MHz), capable of secret key exchange up to more than 90 km.« less

Detector-device-independent quantum key distribution: Security analysis and fast implementation

DOE PAGES

Boaron, Alberto; Korzh, Boris; Houlmann, Raphael; ...

2016-08-09

One of the most pressing issues in quantum key distribution (QKD) is the problem of detector side-channel attacks. To overcome this problem, researchers proposed an elegant “time-reversal” QKD protocol called measurement-device-independent QKD (MDI-QKD), which is based on time-reversed entanglement swapping. But, MDI-QKD is more challenging to implement than standard point-to-point QKD. Recently, we proposed an intermediary QKD protocol called detector-device-independent QKD (DDI-QKD) in order to overcome the drawbacks of MDI-QKD, with the hope that it would eventually lead to a more efficient detector side-channel-free QKD system. We analyze the security of DDI-QKD and elucidate its security assumptions. We find thatmore » DDI-QKD is not equivalent to MDI-QKD, but its security can be demonstrated with reasonable assumptions. On the more practical side, we consider the feasibility of DDI-QKD and present a fast experimental demonstration (clocked at 625 MHz), capable of secret key exchange up to more than 90 km.« less

Development of description framework of pharmacodynamics ontology and its application to possible drug-drug interaction reasoning.

PubMed

Imai, Takeshi; Hayakawa, Masayo; Ohe, Kazuhiko

2013-01-01

Prediction of synergistic or antagonistic effects of drug-drug interaction (DDI) in vivo has been of considerable interest over the years. Formal representation of pharmacological knowledge such as ontology is indispensable for machine reasoning of possible DDIs. However, current pharmacology knowledge bases are not sufficient to provide formal representation of DDI information. With this background, this paper presents: (1) a description framework of pharmacodynamics ontology; and (2) a methodology to utilize pharmacodynamics ontology to detect different types of possible DDI pairs with supporting information such as underlying pharmacodynamics mechanisms. We also evaluated our methodology in the field of drugs related to noradrenaline signal transduction process and 11 different types of possible DDI pairs were detected. The main features of our methodology are the explanation capability of the reason for possible DDIs and the distinguishability of different types of DDIs. These features will not only be useful for providing supporting information to prescribers, but also for large-scale monitoring of drug safety.

MONITORING POTENTIAL DRUG INTERACTIONS AND REACTIONS VIA NETWORK ANALYSIS OF INSTAGRAM USER TIMELINES

PubMed Central

CORREIA, RION BRATTIG; LI, LANG; ROCHA, LUIS M.

2015-01-01

Much recent research aims to identify evidence for Drug-Drug Interactions (DDI) and Adverse Drug reactions (ADR) from the biomedical scientific literature. In addition to this “Bibliome”, the universe of social media provides a very promising source of large-scale data that can help identify DDI and ADR in ways that have not been hitherto possible. Given the large number of users, analysis of social media data may be useful to identify under-reported, population-level pathology associated with DDI, thus further contributing to improvements in population health. Moreover, tapping into this data allows us to infer drug interactions with natural products—including cannabis—which constitute an array of DDI very poorly explored by biomedical research thus far. Our goal is to determine the potential of Instagram for public health monitoring and surveillance for DDI, ADR, and behavioral pathology at large. Most social media analysis focuses on Twitter and Facebook, but Instagram is an increasingly important platform, especially among teens, with unrestricted access of public posts, high availability of posts with geolocation coordinates, and images to supplement textual analysis. Using drug, symptom, and natural product dictionaries for identification of the various types of DDI and ADR evidence, we have collected close to 7000 user timelines spanning from October 2010 to June 2015. We report on 1) the development of a monitoring tool to easily observe user-level timelines associated with drug and symptom terms of interest, and 2) population-level behavior via the analysis of co-occurrence networks computed from user timelines at three different scales: monthly, weekly, and daily occurrences. Analysis of these networks further reveals 3) drug and symptom direct and indirect associations with greater support in user timelines, as well as 4) clusters of symptoms and drugs revealed by the collective behavior of the observed population. This demonstrates that Instagram contains much drug- and pathology specific data for public health monitoring of DDI and ADR, and that complex network analysis provides an important toolbox to extract health-related associations and their support from large-scale social media data. PMID:26776212

MONITORING POTENTIAL DRUG INTERACTIONS AND REACTIONS VIA NETWORK ANALYSIS OF INSTAGRAM USER TIMELINES.

PubMed

Correia, Rion Brattig; Li, Lang; Rocha, Luis M

2016-01-01

Much recent research aims to identify evidence for Drug-Drug Interactions (DDI) and Adverse Drug reactions (ADR) from the biomedical scientific literature. In addition to this "Bibliome", the universe of social media provides a very promising source of large-scale data that can help identify DDI and ADR in ways that have not been hitherto possible. Given the large number of users, analysis of social media data may be useful to identify under-reported, population-level pathology associated with DDI, thus further contributing to improvements in population health. Moreover, tapping into this data allows us to infer drug interactions with natural products-including cannabis-which constitute an array of DDI very poorly explored by biomedical research thus far. Our goal is to determine the potential of Instagram for public health monitoring and surveillance for DDI, ADR, and behavioral pathology at large. Most social media analysis focuses on Twitter and Facebook, but Instagram is an increasingly important platform, especially among teens, with unrestricted access of public posts, high availability of posts with geolocation coordinates, and images to supplement textual analysis. Using drug, symptom, and natural product dictionaries for identification of the various types of DDI and ADR evidence, we have collected close to 7000 user timelines spanning from October 2010 to June 2015.We report on 1) the development of a monitoring tool to easily observe user-level timelines associated with drug and symptom terms of interest, and 2) population-level behavior via the analysis of co-occurrence networks computed from user timelines at three different scales: monthly, weekly, and daily occurrences. Analysis of these networks further reveals 3) drug and symptom direct and indirect associations with greater support in user timelines, as well as 4) clusters of symptoms and drugs revealed by the collective behavior of the observed population. This demonstrates that Instagram contains much drug- and pathology specific data for public health monitoring of DDI and ADR, and that complex network analysis provides an important toolbox to extract health-related associations and their support from large-scale social media data.

Evaluation of medication alerts in electronic health records for compliance with human factors principles

PubMed Central

Phansalkar, Shobha; Zachariah, Marianne; Seidling, Hanna M; Mendes, Chantal; Volk, Lynn; Bates, David W

2014-01-01

Introduction Increasing the adoption of electronic health records (EHRs) with integrated clinical decision support (CDS) is a key initiative of the current US healthcare administration. High over-ride rates of CDS alerts strongly limit these potential benefits. As a result, EHR designers aspire to improve alert design to achieve better acceptance rates. In this study, we evaluated drug–drug interaction (DDI) alerts generated in EHRs and compared them for compliance with human factors principles. Methods We utilized a previously validated questionnaire, the I-MeDeSA, to assess compliance with nine human factors principles of DDI alerts generated in 14 EHRs. Two reviewers independently assigned scores evaluating the human factors characteristics of each EHR. Rankings were assigned based on these scores and recommendations for appropriate alert design were derived. Results The 14 EHRs evaluated in this study received scores ranging from 8 to 18.33, with a maximum possible score of 26. Cohen's κ (κ=0.86) reflected excellent agreement among reviewers. The six vendor products tied for second and third place rankings, while the top system and bottom five systems were home-grown products. The most common weaknesses included the absence of characteristics such as alert prioritization, clear and concise alert messages indicating interacting drugs, actions for clinical management, and a statement indicating the consequences of over-riding the alert. Conclusions We provided detailed analyses of the human factors principles which were assessed and described our recommendations for effective alert design. Future studies should assess whether adherence to these recommendations can improve alert acceptance. PMID:24780721

Alert dwell time: introduction of a measure to evaluate interruptive clinical decision support alerts.

PubMed

McDaniel, Robert B; Burlison, Jonathan D; Baker, Donald K; Hasan, Murad; Robertson, Jennifer; Hartford, Christine; Howard, Scott C; Sablauer, Andras; Hoffman, James M

2016-04-01

Metrics for evaluating interruptive prescribing alerts have many limitations. Additional methods are needed to identify opportunities to improve alerting systems and prevent alert fatigue. In this study, the authors determined whether alert dwell time-the time elapsed from when an interruptive alert is generated to when it is dismissed-could be calculated by using historical alert data from log files. Drug-drug interaction (DDI) alerts from 3 years of electronic health record data were queried. Alert dwell time was calculated for 25,965 alerts, including 777 unique DDIs. The median alert dwell time was 8 s (range, 1-4913 s). Resident physicians had longer median alert dwell times than other prescribers (P < 001). The 10 most frequent DDI alerts (n = 8759 alerts) had shorter median dwell times than alerts that only occurred once (P < 001). This metric can be used in future research to evaluate the effectiveness and efficiency of interruptive prescribing alerts. © The Author 2015. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Utilizing Structures of CYP2D6 and BACE1 Complexes To Reduce Risk of Drug–Drug Interactions with a Novel Series of Centrally Efficacious BACE1 Inhibitors

DOE PAGES

Brodney, Michael A.; Beck, Elizabeth M.; Butler, Christopher R.; ...

2015-03-17

In recent years, the first generation of β-secretase (BACE1) inhibitors advanced into clinical development for the treatment of Alzheimer’s disease (AD). However, the alignment of drug-like properties and selectivity remains a major challenge. Here in this paper, we describe the discovery of a novel class of potent, low clearance, CNS penetrant BACE1 inhibitors represented by thioamidine 5. Further profiling suggested that a high fraction of the metabolism (>95%) was due to CYP2D6, increasing the potential risk for victim-based drug–drug interactions (DDI) and variable exposure in the clinic due to the polymorphic nature of this enzyme. To guide future design, wemore » solved crystal structures of CYP2D6 complexes with substrate 5 and its corresponding metabolic product pyrazole 6, which provided insight into the binding mode and movements between substrate/inhibitor complexes. Guided by the BACE1 and CYP2D6 crystal structures, we designed and synthesized analogues with reduced risk for DDI, central efficacy, and improved hERG therapeutic margins.« less

Utilizing Structures of CYP2D6 and BACE1 Complexes To Reduce Risk of Drug–Drug Interactions with a Novel Series of Centrally Efficacious BACE1 Inhibitors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brodney, Michael A.; Beck, Elizabeth M.; Butler, Christopher R.

In recent years, the first generation of β-secretase (BACE1) inhibitors advanced into clinical development for the treatment of Alzheimer’s disease (AD). However, the alignment of drug-like properties and selectivity remains a major challenge. Here in this paper, we describe the discovery of a novel class of potent, low clearance, CNS penetrant BACE1 inhibitors represented by thioamidine 5. Further profiling suggested that a high fraction of the metabolism (>95%) was due to CYP2D6, increasing the potential risk for victim-based drug–drug interactions (DDI) and variable exposure in the clinic due to the polymorphic nature of this enzyme. To guide future design, wemore » solved crystal structures of CYP2D6 complexes with substrate 5 and its corresponding metabolic product pyrazole 6, which provided insight into the binding mode and movements between substrate/inhibitor complexes. Guided by the BACE1 and CYP2D6 crystal structures, we designed and synthesized analogues with reduced risk for DDI, central efficacy, and improved hERG therapeutic margins.« less

Neuropathogenicity of Two Saffold Virus Type 3 Isolates in Mouse Models

PubMed Central

Kotani, Osamu; Naeem, Asif; Suzuki, Tadaki; Iwata-Yoshikawa, Naoko; Sato, Yuko; Nakajima, Noriko; Hosomi, Takushi; Tsukagoshi, Hiroyuki; Kozawa, Kunihisa; Hasegawa, Hideki; Taguchi, Fumihiro; Shimizu, Hiroyuki; Nagata, Noriyo

2016-01-01

Objective Saffold virus (SAFV), a picornavirus, is occasionally detected in children with acute flaccid paralysis, meningitis, and cerebellitis; however, the neuropathogenicity of SAFV remains undetermined. Methods The virulence of two clinical isolates of SAFV type 3 (SAFV-3) obtained from a patient with aseptic meningitis (AM strain) and acute upper respiratory inflammation (UR strain) was analyzed in neonatal and young mice utilizing virological, pathological, and immunological methods. Results The polyproteins of the strains differed in eight amino acids. Both clinical isolates were infective, exhibited neurotropism, and were mildly neurovirulent in neonatal ddY mice. Both strains pathologically infected neural progenitor cells and glial cells, but not large neurons, with the UR strain also infecting epithelial cells. UR infection resulted in longer inflammation in the brain and spinal cord because of demyelination, while the AM strain showed more infectivity in the cerebellum in neonatal ddY mice. Additionally, young BALB/c mice seroconverted following mucosal inoculation with the UR, but not the AM, strain. Conclusions Both SAFV-3 isolates had neurotropism and mild neurovirulence but showed different cell tropisms in both neonatal and young mouse models. This animal model has the potential to recapitulate the potential neuropathogenicity of SAFV-3. PMID:26828718

Computerized techniques pave the way for drug-drug interaction prediction and interpretation

PubMed Central

Safdari, Reza; Ferdousi, Reza; Aziziheris, Kamal; Niakan-Kalhori, Sharareh R.; Omidi, Yadollah

2016-01-01

Introduction: Health care industry also patients penalized by medical errors that are inevitable but highly preventable. Vast majority of medical errors are related to adverse drug reactions, while drug-drug interactions (DDIs) are the main cause of adverse drug reactions (ADRs). DDIs and ADRs have mainly been reported by haphazard case studies. Experimental in vivo and in vitro researches also reveals DDI pairs. Laboratory and experimental researches are valuable but also expensive and in some cases researchers may suffer from limitations. Methods: In the current investigation, the latest published works were studied to analyze the trend and pattern of the DDI modelling and the impacts of machine learning methods. Applications of computerized techniques were also investigated for the prediction and interpretation of DDIs. Results: Computerized data-mining in pharmaceutical sciences and related databases provide new key transformative paradigms that can revolutionize the treatment of diseases and hence medical care. Given that various aspects of drug discovery and pharmacotherapy are closely related to the clinical and molecular/biological information, the scientifically sound databases (e.g., DDIs, ADRs) can be of importance for the success of pharmacotherapy modalities. Conclusion: A better understanding of DDIs not only provides a robust means for designing more effective medicines but also grantees patient safety. PMID:27525223

Age related changes in fractional elimination pathways for drugs: assessing the impact of variable ontogeny on metabolic drug-drug interactions.

PubMed

Salem, Farzaneh; Johnson, Trevor N; Barter, Zoe E; Leeder, J Steven; Rostami-Hodjegan, Amin

2013-08-01

The magnitude of any metabolic drug-drug interactions (DDIs) depends on fractional importance of inhibited pathway which may not necessarily be the same in young children when compared to adults. The ontogeny pattern of cytochrome P450 (CYP) enzymes (CYPs 1A2, 2B6, 2C8, 2C9, 2C18/19, 2D6, 2E1, 3A4) and renal function were analyzed systematically. Bootstrap methodology was used to account for variability, and to define the age range over which statistical differences existed between each pair of specific pathways. A number of DDIs were simulated (Simcyp Pediatric v12) for virtual compounds to highlight effects of age on fractional elimination and consequent magnitude of DDI. For a theoretical drug metabolized 50% by each of CYP2D6 and CYP3A4 pathways at birth, co-administration of ketoconazole (3 mg/kg) resulted in a 1.65-fold difference between inhibited versus uninhibited AUC compared to 2.4-fold in 1 year olds and 3.2-fold in adults. Conversely, neonates could be more sensitive to DDI than adults in certain scenarios. Thus, extrapolation from adult data may not be applicable across all pediatric age groups. The use of pediatric physiologically based pharmacokinetic (p-PBPK) models may offer an interim solution to uncovering potential periods of vulnerability to DDI where there are no existing clinical data derived from children. © The Author(s) 2013.

Utilizing the Wikidata system to improve the quality of medical content in Wikipedia in diverse languages: a pilot study.

PubMed

Pfundner, Alexander; Schönberg, Tobias; Horn, John; Boyce, Richard D; Samwald, Matthias

2015-05-05

Wikipedia is an important source of medical information for both patients and medical professionals. Given its wide reach, improving the quality, completeness, and accessibility of medical information on Wikipedia could have a positive impact on global health. We created a prototypical implementation of an automated system for keeping drug-drug interaction (DDI) information in Wikipedia up to date with current evidence about clinically significant drug interactions. Our work is based on Wikidata, a novel, graph-based database backend of Wikipedia currently in development. We set up an automated process for integrating data from the Office of the National Coordinator for Health Information Technology (ONC) high priority DDI list into Wikidata. We set up exemplary implementations demonstrating how the DDI data we introduced into Wikidata could be displayed in Wikipedia articles in diverse languages. Finally, we conducted a pilot analysis to explore if adding the ONC high priority data would substantially enhance the information currently available on Wikipedia. We derived 1150 unique interactions from the ONC high priority list. Integration of the potential DDI data from Wikidata into Wikipedia articles proved to be straightforward and yielded useful results. We found that even though the majority of current English Wikipedia articles about pharmaceuticals contained sections detailing contraindications, only a small fraction of articles explicitly mentioned interaction partners from the ONC high priority list. For 91.30% (1050/1150) of the interaction pairs we tested, none of the 2 articles corresponding to the interacting substances explicitly mentioned the interaction partner. For 7.21% (83/1150) of the pairs, only 1 of the 2 associated Wikipedia articles mentioned the interaction partner; for only 1.48% (17/1150) of the pairs, both articles contained explicit mentions of the interaction partner. Our prototype demonstrated that automated updating of medical content in Wikipedia through Wikidata is a viable option, albeit further refinements and community-wide consensus building are required before integration into public Wikipedia is possible. A long-term endeavor to improve the medical information in Wikipedia through structured data representation and automated workflows might lead to a significant improvement of the quality of medical information in one of the world's most popular Web resources.

Utilizing the Wikidata System to Improve the Quality of Medical Content in Wikipedia in Diverse Languages: A Pilot Study

PubMed Central

Pfundner, Alexander; Schönberg, Tobias; Horn, John; Boyce, Richard D

2015-01-01

Background Wikipedia is an important source of medical information for both patients and medical professionals. Given its wide reach, improving the quality, completeness, and accessibility of medical information on Wikipedia could have a positive impact on global health. Objective We created a prototypical implementation of an automated system for keeping drug-drug interaction (DDI) information in Wikipedia up to date with current evidence about clinically significant drug interactions. Our work is based on Wikidata, a novel, graph-based database backend of Wikipedia currently in development. Methods We set up an automated process for integrating data from the Office of the National Coordinator for Health Information Technology (ONC) high priority DDI list into Wikidata. We set up exemplary implementations demonstrating how the DDI data we introduced into Wikidata could be displayed in Wikipedia articles in diverse languages. Finally, we conducted a pilot analysis to explore if adding the ONC high priority data would substantially enhance the information currently available on Wikipedia. Results We derived 1150 unique interactions from the ONC high priority list. Integration of the potential DDI data from Wikidata into Wikipedia articles proved to be straightforward and yielded useful results. We found that even though the majority of current English Wikipedia articles about pharmaceuticals contained sections detailing contraindications, only a small fraction of articles explicitly mentioned interaction partners from the ONC high priority list. For 91.30% (1050/1150) of the interaction pairs we tested, none of the 2 articles corresponding to the interacting substances explicitly mentioned the interaction partner. For 7.21% (83/1150) of the pairs, only 1 of the 2 associated Wikipedia articles mentioned the interaction partner; for only 1.48% (17/1150) of the pairs, both articles contained explicit mentions of the interaction partner. Conclusions Our prototype demonstrated that automated updating of medical content in Wikipedia through Wikidata is a viable option, albeit further refinements and community-wide consensus building are required before integration into public Wikipedia is possible. A long-term endeavor to improve the medical information in Wikipedia through structured data representation and automated workflows might lead to a significant improvement of the quality of medical information in one of the world’s most popular Web resources. PMID:25944105

Detector-device-independent quantum key distribution: Security analysis and fast implementation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Boaron, Alberto; Korzh, Boris; Boso, Gianluca

One of the most pressing issues in quantum key distribution (QKD) is the problem of detector side-channel attacks. To overcome this problem, researchers proposed an elegant “time-reversal” QKD protocol called measurement-device-independent QKD (MDI-QKD), which is based on time-reversed entanglement swapping. However, MDI-QKD is more challenging to implement than standard point-to-point QKD. Recently, an intermediary QKD protocol called detector-device-independent QKD (DDI-QKD) has been proposed to overcome the drawbacks of MDI-QKD, with the hope that it would eventually lead to a more efficient detector side-channel-free QKD system. Here, we analyze the security of DDI-QKD and elucidate its security assumptions. We find thatmore » DDI-QKD is not equivalent to MDI-QKD, but its security can be demonstrated with reasonable assumptions. On the more practical side, we consider the feasibility of DDI-QKD and present a fast experimental demonstration (clocked at 625 MHz), capable of secret key exchange up to more than 90 km.« less

Fluorescent pseudorotaxanes of a quinodicarbocyanine dye with gamma cyclodextrin

NASA Astrophysics Data System (ADS)

Bernstein, Olivia M.; McGee, Tiffany E.; Silzel, Lisa E.; Silzel, John W.

2018-01-01

Spectrophotometric titration of buffered solutions of gamma cyclodextrin (γCD) and 1,1‧-diethyl,2,2‧-dicarbocyanine (DDI) demonstrates extension of the known 1:2 host:guest complex to form a previously unreported 2:2 complex near the γCD solubility limit. Though DDI is predominantly hosted as a non-fluorescent H-aggregate, both complexes exist in respective equilibria with two secondary complexes hosting unaggregated DDI as 1:1 and 2:1 complexes. The 2:1 complex exhibits significant fluorescence emission, with a quantum yield six times that of DDI in organic solvents, but ten times lower than that of an analogous indodicarbocyanine. Fragment Molecular Orbital calculations suggest that the 2:1 complex has the tail-to-tail conformation, and that solvent access to the dye strongly favors photoisomerization. In the host-guest complex, γCD limits solvent access to the dye and hinders rotation of the quinolyl terminal groups, but nevertheless pairwise rotation of methine carbons within the γCD cavity likely remains as a significant nonradiative relaxation pathway for the excited state.

Novel mutation in the human immunodeficiency virus type 1 reverse transcriptase gene that encodes cross-resistance to 2',3'-dideoxyinosine and 2',3'-dideoxycytidine.

PubMed Central

Gu, Z; Gao, Q; Li, X; Parniak, M A; Wainberg, M A

1992-01-01

We have used the technique of in vitro selection to generate variants of human immunodeficiency virus type 1 (HIV-1) that are resistant to 2',3'-dideoxyinosine (ddI) and cross-resistant to 2',3'-dideoxycytidine (ddC). The complete reverse transcriptase (RT)-coding regions, plus portions of flanking sequences, of viruses possessing a ddI-resistant phenotype were cloned and sequenced by polymerase chain reaction (PCR)-based methods. We observed that several of these viruses possessed mutations at amino acid sites 184 (Met-->Val; ATG-->GTG) and 294 (Pro-->Ser; CCA-->TCA). These mutations were introduced in the pol gene of infectious, cloned HXB2-D DNA by site-directed mutagenesis. Viral replication assays confirmed the importance of site 184 with regard to resistance to ddI. The recombinant viruses thus generated displayed more than fivefold-greater resistance to ddI than parental HXB2-D did. Moreover, more than fivefold-greater resistance to ddC was also documented; however, the recombinant viruses continued to be inhibited by zidovudine (AZT). No resistance to ddI, ddC, or AZT was introduced by inclusion of mutation site 294 in the pol gene of HXB2-D. PCR analysis performed on viral samples obtained from patients receiving long-term ddI therapy confirmed the presence of mutation site 184 in five of seven cases tested. In three of these five positive cases, the wild-type codon was also detected, indicating that mixtures of viral quasispecies were apparently present. Viruses possessing a ddI resistance phenotype were isolated from both subjects whose viruses contained only the mutated rather than wild-type codon at position 184 as well as from a third individual, whose viruses appeared to be mostly of the mutated variety. Images PMID:1279198

Recommendations for Selecting Drug-Drug Interactions for Clinical Decision Support

PubMed Central

Tilson, Hugh; Hines, Lisa E.; McEvoy, Gerald; Weinstein, David M.; Hansten, Philip D.; Matuszewski, Karl; le Comte, Marianne; Higby-Baker, Stefanie; Hanlon, Joseph T.; Pezzullo, Lynn; Vieson, Kathleen; Helwig, Amy L.; Huang, Shiew-Mei; Perre, Anthony; Bates, David W.; Poikonen, John; Wittie, Michael A.; Grizzle, Amy J.; Brown, Mary; Malone, Daniel C.

2016-01-01

Purpose To recommend principles for including drug-drug interactions (DDIs) in clinical decision support. Methods A conference series was conducted to improve clinical decision support (CDS) for DDIs. The Content Workgroup met monthly by webinar from January 2013 to February 2014, with two in-person meetings to reach consensus. The workgroup consisted of 20 experts in pharmacology, drug information, and CDS from academia, government agencies, health information (IT) vendors, and healthcare organizations. Workgroup members addressed four key questions: (1) What process should be used to develop and maintain a standard set of DDIs?; (2) What information should be included in a knowledgebase of standard DDIs?; (3) Can/should a list of contraindicated drug pairs be established?; and (4) How can DDI alerts be more intelligently filtered? Results To develop and maintain a standard set of DDIs for CDS in the United States, we recommend a transparent, systematic, and evidence-driven process with graded recommendations by a consensus panel of experts and oversight by a national organization. We outline key DDI information needed to help guide clinician decision-making. We recommend judicious classification of DDIs as contraindicated, as only a small set of drug combinations are truly contraindicated. Finally, we recommend more research to identify methods to safely reduce repetitive and less relevant alerts. Conclusion A systematic ongoing process is necessary to select DDIs for alerting clinicians. We anticipate that our recommendations can lead to consistent and clinically relevant content for interruptive DDIs, and thus reduce alert fatigue and improve patient safety. PMID:27045070

Comparison of Overridden Medication-related Clinical Decision Support in the Intensive Care Unit between a Commercial System and a Legacy System.

PubMed

Wong, Adrian; Wright, Adam; Seger, Diane L; Amato, Mary G; Fiskio, Julie M; Bates, David

2017-08-23

Electronic health records (EHRs) with clinical decision support (CDS) have shown to be effective at improving patient safety. Despite this, alerts delivered as part of CDS are overridden frequently, which is of concern in the critical care population as this group may have an increased risk of harm. Our organization recently transitioned from an internally-developed EHR to a commercial system. Data comparing various EHR systems, especially after transitions between EHRs, are needed to identify areas for improvement. To compare the two systems and identify areas for potential improvement with the new commercial system at a single institution. Overridden medication-related CDS alerts were included from October to December of the systems' respective years (legacy, 2011; commercial, 2015), restricted to three intensive care units. The two systems were compared with regards to CDS presentation and override rates for four types of CDS: drug-allergy, drug-drug interaction (DDI), geriatric and renal alerts. A post hoc analysis to evaluate for adverse drug events (ADEs) potentially resulting from overridden alerts was performed for 'contraindicated' DDIs via chart review. There was a significant increase in provider exposure to alerts and alert overrides in the commercial system (commercial: n=5,535; legacy: n=1,030). Rates of overrides were higher for the allergy and DDI alerts (p<0.001) in the commercial system. Geriatric and renal alerts were significantly different in incidence and presentation between the two systems. No ADEs were identified in an analysis of 43 overridden contraindicated DDI alerts. The vendor system had much higher rates of both alerts and overrides, although we did not find evidence of harm in a review of DDIs which were overridden. We propose recommendations for improving our current system which may be helpful to other similar institutions; improving both alert presentation and the underlying knowledge base appear important.

Differential phosphorylation of azidothymidine, dideoxycytidine, and dideoxyinosine in resting and activated peripheral blood mononuclear cells.

PubMed Central

Gao, W Y; Shirasaka, T; Johns, D G; Broder, S; Mitsuya, H

1993-01-01

The antiviral activity of azidothymidine (AZT), dideoxycytidine (ddC), and dideoxyinosine (ddI) against HIV-1 was comparatively evaluated in PHA-stimulated PBM. The mean drug concentration which yielded 50% p24 Gag negative cultures were substantially different: 0.06, 0.2, and 6 microM for AZT, ddC, and ddI, respectively. We found that AZT was preferentially phosphorylated to its triphosphate (TP) form in PHA-PBM rather than unstimulated, resting PBM (R-PBM), producing 10- to 17-fold higher ratios of AZTTP/dTTP in PHA-PBM than in R-PBM. The phosphorylation of ddC and ddI to their TP forms was, however, much less efficient in PHA-PBM, resulting in approximately 5-fold and approximately 15-fold lower ratios of ddCTP/dCTP and ddATP/dATP, respectively, in PHA-PBM than in R-PBM. The comparative order of PHA-induced increase in cellular enzyme activities examined was: thymidine kinase > uridine kinase > deoxycytidine kinase > adenosine kinase > 5'-nucleotidase. We conclude that AZT, ddC, and ddI exert disproportionate antiviral effects depending on the activation state of the target cells, i.e., ddI and ddC exert antiviral activity more favorably in resting cells than in activated cells, while AZT preferentially protects activated cells against HIV infection. Considering that HIV-1 proviral DNA synthesis in resting lymphocytes is reportedly initiated at levels comparable with those of activated lymphocytes, the current data should have practical relevance in the design of anti-HIV chemotherapy, particularly combination chemotherapy. PMID:8387546

Developing strategies for predicting hyperkalemia in potassium-increasing drug-drug interactions.

PubMed

Eschmann, Emmanuel; Beeler, Patrick Emanuel; Schneemann, Markus; Blaser, Jürg

2017-01-01

To compare different strategies predicting hyperkalemia (serum potassium level ≥5.5 mEq/l) in hospitalized patients for whom medications triggering potassium-increasing drug-drug interactions (DDIs) were ordered. We investigated 5 strategies that combined prediction triggered at onset of DDI versus continuous monitoring and taking into account an increasing number of patient parameters. The considered patient parameters were identified using generalized additive models, and the thresholds of the prediction strategies were calculated by applying Youden's J statistic to receiver operation characteristic curves. Half of the data served as the calibration set, half as the validation set. We identified 132 incidences of hyperkalemia induced by 8413 potentially severe potassium-increasing DDIs among 76 467 patients. The positive predictive value (PPV) of those strategies predicting hyperkalemia at the onset of DDI ranged from 1.79% (undifferentiated anticipation of hyperkalemia due to the DDI) to 3.02% (additionally considering the baseline serum potassium) and 3.10% (including further patient parameters). Continuous monitoring significantly increased the PPV to 8.25% (considering the current serum potassium) and 9.34% (additional patient parameters). Continuous monitoring of the risk for hyperkalemia based on current potassium level shows a better predictive power than predictions triggered at the onset of DDI. This contrasts with efforts to improve DDI alerts by taking into account more patient parameters at the time of ordering. © The Author 2016. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Comparing Various In Vitro Prediction Criteria to Assess the Potential of a New Molecular Entity to Inhibit Organic Anion Transporting Polypeptide 1B1.

PubMed

Vaidyanathan, Jayabharathi; Yoshida, Kenta; Arya, Vikram; Zhang, Lei

2016-07-01

Evaluation of organic anion transporting polypeptide (OATP) 1B1-mediated drug-drug interactions (DDIs) is an integral part of drug development and is recommended by regulatory agencies. In this study we compared various prediction methods and cutoff criteria based on in vitro inhibition data to assess the potential of a new molecular entity to inhibit OATP1B1 in vivo. In vitro (eg, IC50 , fu,p ) and in vivo (eg, dose, Cmax , change in area under the curve [AUC]) data for 11 substrates and 61 inhibitors for OATP1B1 were obtained from literature and Drugs@FDA, which include 107 clinical (in vivo) DDI studies. Substrate dependency and variability of IC50 values were noted. In addition to the ratio of unbound or total systemic concentration (Imax,u and Imax ) to IC50 , maximum unbound inhibitor concentration at the inlet to the liver (Iu,in,max ) was used for the estimation of "R value" where R = 1 + Iu,in,max /IC50 . Based on our analyses, Imax /Ki ≥ 0.1, R ≥ 1.04, or R ≥ 1.1 seem to be appropriate for reducing the false-negative (FN) predictions. However, as compared with R ≥ 1.1, Imax /Ki ≥ 0.1 and R ≥ 1.04 resulted in higher false positives (FPs) and lower true negatives (TNs). R ≥ 1.1, Imax,u /Ki ≥ 0.02, and R ≥ 1.25 alone, or combined criterion of Imax /Ki ≥ 0.1 and R ≥ 1.25, were reasonable to determine the need to perform clinical DDI studies with OATP1B1 substrates with similar positive and negative predictive values. Possible reasons of FP or FN from different decision criteria should be considered when interpreting prediction results, and the variability in IC50 determination needs to be understood and minimized. © 2016, The American College of Clinical Pharmacology.

Hepatic transporter drug-drug interactions: an evaluation of approaches and methodologies.

PubMed

Williamson, Beth; Riley, Robert J

2017-12-01

Drug-drug interactions (DDIs) continue to account for 5% of hospital admissions and therefore remain a major regulatory concern. Effective, quantitative prediction of DDIs will reduce unexpected clinical findings and encourage projects to frontload DDI investigations rather than concentrating on risk management ('manage the baggage') later in drug development. A key challenge in DDI prediction is the discrepancies between reported models. Areas covered: The current synopsis focuses on four recent influential publications on hepatic drug transporter DDIs using static models that tackle interactions with individual transporters and in combination with other drug transporters and metabolising enzymes. These models vary in their assumptions (including input parameters), transparency, reproducibility and complexity. In this review, these facets are compared and contrasted with recommendations made as to their application. Expert opinion: Over the past decade, static models have evolved from simple [I]/k i models to incorporate victim and perpetrator disposition mechanisms including the absorption rate constant, the fraction of the drug metabolised/eliminated and/or clearance concepts. Nonetheless, models that comprise additional parameters and complexity do not necessarily out-perform simpler models with fewer inputs. Further, consideration of the property space to exploit some drug target classes has also highlighted the fine balance required between frontloading and back-loading studies to design out or 'manage the baggage'.

Development and preliminary evidence for the validity of an instrument assessing implementation of human-factors principles in medication-related decision-support systems—I-MeDeSA

PubMed Central

Zachariah, Marianne; Seidling, Hanna M; Neri, Pamela M; Cresswell, Kathrin M; Duke, Jon; Bloomrosen, Meryl; Volk, Lynn A; Bates, David W

2011-01-01

Background Medication-related decision support can reduce the frequency of preventable adverse drug events. However, the design of current medication alerts often results in alert fatigue and high over-ride rates, thus reducing any potential benefits. Methods The authors previously reviewed human-factors principles for relevance to medication-related decision support alerts. In this study, instrument items were developed for assessing the appropriate implementation of these human-factors principles in drug–drug interaction (DDI) alerts. User feedback regarding nine electronic medical records was considered during the development process. Content validity, construct validity through correlation analysis, and inter-rater reliability were assessed. Results The final version of the instrument included 26 items associated with nine human-factors principles. Content validation on three systems resulted in the addition of one principle (Corrective Actions) to the instrument and the elimination of eight items. Additionally, the wording of eight items was altered. Correlation analysis suggests a direct relationship between system age and performance of DDI alerts (p=0.0016). Inter-rater reliability indicated substantial agreement between raters (κ=0.764). Conclusion The authors developed and gathered preliminary evidence for the validity of an instrument that measures the appropriate use of human-factors principles in the design and display of DDI alerts. Designers of DDI alerts may use the instrument to improve usability and increase user acceptance of medication alerts, and organizations selecting an electronic medical record may find the instrument helpful in meeting their clinicians' usability needs. PMID:21946241

Interferometric detection of freeze-thaw displacements of Alaskan permafrost using ERS-1 data

NASA Technical Reports Server (NTRS)

Werner, Charles L.; Gabriel, Andrew K.

1993-01-01

The possibility of making large scale (50 km) measurements of motions of the earth's surface with high resolution (10 m) and very high accuracy (1 cm) from multipass SAR interferometry was established in 1989. Other experiments have confirmed the viability and usefulness of the method. Work is underway in various groups to measure displacements from volcanic activity, seismic events, glacier motion, and in the present study, freeze-thaw cycles in Alaskan permafrost. The ground is known to move significantly in these cycles, and provided that freezing does not cause image decorrelation, it should be possible to measure both ground swelling and subsidence. The authors have obtained data from multiple passes of ERS-1 over the Toolik Lake region of northern Alaska of suitable quality for interferometry. The data are processed into images, and single interferograms are formed in the usual manner. Phase unwrapping is performed, and the multipass baselines are estimated from the images using both orbit ephemerides and scene tie points. The phases are scaled by the baseline ratio, and a double-difference interferogram (DDI) is formed. It is found that there is a residual 'saddle-shape' phase error across the image, which is postulated to be caused by a small divergence (10(exp -2) deg.) in the orbits. A simulation of a DDI from divergent orbits confirms the shape and magnitude of the error. A two-dimensional least squares fit to the error is performed, which is used to correct the DDI. The final, corrected DDI shows significant phase (altitude) changes over the period of the observation.

Prevalence of Different Combinations of Antiepileptic Drugs and CNS Drugs in Elderly Home Care Service and Nursing Home Patients in Norway.

PubMed

Halvorsen, Kjell H; Johannessen Landmark, Cecilie; Granas, Anne Gerd

2016-01-01

Introduction. Antiepileptic drugs (AEDs) are used to treat different conditions in elderly patients and are among the drug classes most susceptible to be involved in drug-drug interactions (DDI). The aim of the study was to describe and compare use of AEDs between home care service and nursing home patients, as these patients are not included in nationwide databases of drug utilization. In the combined population, we investigate DDI of AEDs with other central nervous system- (CNS-) active drugs and DDIs involving AEDs in general. Materials and Methods. Point-prevalence study of Norwegian patients in home care services and nursing homes in 2009. At the patient level, we screened for different DDIs involving AEDs. Results. In total, 882 patients (7.8%) of 11,254 patients used AEDs and number of users did not differ between home care services and nursing homes (8.2% versus 7.7%). In the combined population, we identified 436 potential DDIs in 45% of the patients. Conclusions. In a large population of elderly, home care service and nursing home patients do not differ with respect to exposure of AEDs but use more AEDs as compared to the general population of similar age. The risk of DDIs with AEDs and other CNS-active drugs should be taken into consideration and individual clinical evaluations are assessed in this population.

Predicting and understanding comprehensive drug-drug interactions via semi-nonnegative matrix factorization.

PubMed

Yu, Hui; Mao, Kui-Tao; Shi, Jian-Yu; Huang, Hua; Chen, Zhi; Dong, Kai; Yiu, Siu-Ming

2018-04-11

Drug-drug interactions (DDIs) always cause unexpected and even adverse drug reactions. It is important to identify DDIs before drugs are used in the market. However, preclinical identification of DDIs requires much money and time. Computational approaches have exhibited their abilities to predict potential DDIs on a large scale by utilizing pre-market drug properties (e.g. chemical structure). Nevertheless, none of them can predict two comprehensive types of DDIs, including enhancive and degressive DDIs, which increases and decreases the behaviors of the interacting drugs respectively. There is a lack of systematic analysis on the structural relationship among known DDIs. Revealing such a relationship is very important, because it is able to help understand how DDIs occur. Both the prediction of comprehensive DDIs and the discovery of structural relationship among them play an important guidance when making a co-prescription. In this work, treating a set of comprehensive DDIs as a signed network, we design a novel model (DDINMF) for the prediction of enhancive and degressive DDIs based on semi-nonnegative matrix factorization. Inspiringly, DDINMF achieves the conventional DDI prediction (AUROC = 0.872 and AUPR = 0.605) and the comprehensive DDI prediction (AUROC = 0.796 and AUPR = 0.579). Compared with two state-of-the-art approaches, DDINMF shows it superiority. Finally, representing DDIs as a binary network and a signed network respectively, an analysis based on NMF reveals crucial knowledge hidden among DDIs. Our approach is able to predict not only conventional binary DDIs but also comprehensive DDIs. More importantly, it reveals several key points about the DDI network: (1) both binary and signed networks show fairly clear clusters, in which both drug degree and the difference between positive degree and negative degree show significant distribution; (2) the drugs having large degrees tend to have a larger difference between positive degree and negative degree; (3) though the binary DDI network contains no information about enhancive and degressive DDIs at all, it implies some of their relationship in the comprehensive DDI matrix; (4) the occurrence of signs indicating enhancive and degressive DDIs is not random because the comprehensive DDI network is equipped with a structural balance.

Building Capacity Through Hands-on Computational Internships to Assure Reproducible Results and Implementation of Digital Documentation in the ICERT REU Program

NASA Astrophysics Data System (ADS)

Gomez, R.; Gentle, J.

2015-12-01

Modern data pipelines and computational processes require that meticulous methodologies be applied in order to insure that the source data, algorithms, and results are properly curated, managed and retained while remaining discoverable, accessible, and reproducible. Given the complexity of understanding the scientific problem domain being researched, combined with the overhead of learning to use advanced computing technologies, it becomes paramount that the next generation of scientists and researchers learn to embrace best-practices. The Integrative Computational Education and Research Traineeship (ICERT) is a National Science Foundation (NSF) Research Experience for Undergraduates (REU) Site at the Texas Advanced Computing Center (TACC). During Summer 2015, two ICERT interns joined the 3DDY project. 3DDY converts geospatial datasets into file types that can take advantage of new formats, such as natural user interfaces, interactive visualization, and 3D printing. Mentored by TACC researchers for ten weeks, students with no previous background in computational science learned to use scripts to build the first prototype of the 3DDY application, and leveraged Wrangler, the newest high performance computing (HPC) resource at TACC. Test datasets for quadrangles in central Texas were used to assemble the 3DDY workflow and code. Test files were successfully converted into a stereo lithographic (STL) format, which is amenable for use with a 3D printers. Test files and the scripts were documented and shared using the Figshare site while metadata was documented for the 3DDY application using OntoSoft. These efforts validated a straightforward set of workflows to transform geospatial data and established the first prototype version of 3DDY. Adding the data and software management procedures helped students realize a broader set of tangible results (e.g. Figshare entries), better document their progress and the final state of their work for the research group and community, helped students and researchers follow a clear set of formats and fill in the necessary details that may be lost otherwise, and exposed the students to the next generation workflows and practices for digital scholarship and scientific inquiry for converting geospatial data into formats that are easy to reuse.

Similarity-based modeling in large-scale prediction of drug-drug interactions.

PubMed

Vilar, Santiago; Uriarte, Eugenio; Santana, Lourdes; Lorberbaum, Tal; Hripcsak, George; Friedman, Carol; Tatonetti, Nicholas P

2014-09-01

Drug-drug interactions (DDIs) are a major cause of adverse drug effects and a public health concern, as they increase hospital care expenses and reduce patients' quality of life. DDI detection is, therefore, an important objective in patient safety, one whose pursuit affects drug development and pharmacovigilance. In this article, we describe a protocol applicable on a large scale to predict novel DDIs based on similarity of drug interaction candidates to drugs involved in established DDIs. The method integrates a reference standard database of known DDIs with drug similarity information extracted from different sources, such as 2D and 3D molecular structure, interaction profile, target and side-effect similarities. The method is interpretable in that it generates drug interaction candidates that are traceable to pharmacological or clinical effects. We describe a protocol with applications in patient safety and preclinical toxicity screening. The time frame to implement this protocol is 5-7 h, with additional time potentially necessary, depending on the complexity of the reference standard DDI database and the similarity measures implemented.

Automatic exposure control calibration and optimisation for abdomen, pelvis and lumbar spine imaging with an Agfa computed radiography system.

PubMed

Moore, C S; Wood, T J; Avery, G; Balcam, S; Needler, L; Joshi, H; Saunderson, J R; Beavis, A W

2016-11-07

The use of three physical image quality metrics, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR) and mean effective noise equivalent quanta (eNEQ m ) have recently been examined by our group for their appropriateness in the calibration of an automatic exposure control (AEC) device for chest radiography with an Agfa computed radiography (CR) imaging system. This study uses the same methodology but investigates AEC calibration for abdomen, pelvis and spine CR imaging. AEC calibration curves were derived using a simple uniform phantom (equivalent to 20 cm water) to ensure each metric was held constant across the tube voltage range. Each curve was assessed for its clinical appropriateness by generating computer simulated abdomen, pelvis and spine images (created from real patient CT datasets) with appropriate detector air kermas for each tube voltage, and grading these against reference images which were reconstructed at detector air kermas correct for the constant detector dose indicator (DDI) curve currently programmed into the AEC device. All simulated images contained clinically realistic projected anatomy and were scored by experienced image evaluators. Constant DDI and CNR curves did not provide optimized performance but constant eNEQ m and SNR did, with the latter being the preferred calibration metric given that it is easier to measure in practice. This result was consistent with the previous investigation for chest imaging with AEC devices. Medical physicists may therefore use a simple and easily accessible uniform water equivalent phantom to measure the SNR image quality metric described here when calibrating AEC devices for abdomen, pelvis and spine imaging with Agfa CR systems, in the confidence that clinical image quality will be sufficient for the required clinical task. However, to ensure appropriate levels of detector air kerma the advice of expert image evaluators must be sought.

Automatic exposure control calibration and optimisation for abdomen, pelvis and lumbar spine imaging with an Agfa computed radiography system

NASA Astrophysics Data System (ADS)

Moore, C. S.; Wood, T. J.; Avery, G.; Balcam, S.; Needler, L.; Joshi, H.; Saunderson, J. R.; Beavis, A. W.

2016-11-01

The use of three physical image quality metrics, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR) and mean effective noise equivalent quanta (eNEQm) have recently been examined by our group for their appropriateness in the calibration of an automatic exposure control (AEC) device for chest radiography with an Agfa computed radiography (CR) imaging system. This study uses the same methodology but investigates AEC calibration for abdomen, pelvis and spine CR imaging. AEC calibration curves were derived using a simple uniform phantom (equivalent to 20 cm water) to ensure each metric was held constant across the tube voltage range. Each curve was assessed for its clinical appropriateness by generating computer simulated abdomen, pelvis and spine images (created from real patient CT datasets) with appropriate detector air kermas for each tube voltage, and grading these against reference images which were reconstructed at detector air kermas correct for the constant detector dose indicator (DDI) curve currently programmed into the AEC device. All simulated images contained clinically realistic projected anatomy and were scored by experienced image evaluators. Constant DDI and CNR curves did not provide optimized performance but constant eNEQm and SNR did, with the latter being the preferred calibration metric given that it is easier to measure in practice. This result was consistent with the previous investigation for chest imaging with AEC devices. Medical physicists may therefore use a simple and easily accessible uniform water equivalent phantom to measure the SNR image quality metric described here when calibrating AEC devices for abdomen, pelvis and spine imaging with Agfa CR systems, in the confidence that clinical image quality will be sufficient for the required clinical task. However, to ensure appropriate levels of detector air kerma the advice of expert image evaluators must be sought.

Didanosine polymorphism in a supercritical antisolvent process.

PubMed

Bettini, R; Menabeni, R; Tozzi, R; Pranzo, M B; Pasquali, I; Chierotti, M R; Gobetto, R; Pellegrino, L

2010-04-01

Solid-state properties of active ingredients are crucial in pharmaceutical development owing to their significant clinical and economical implications. In the present work we investigated the solid-state properties and the solubility in water of didanosine, DDI, re-crystallized from a dimethylsulfoxide solution using supercritical CO(2) as an antisolvent (SAS process) for comparison with the commercially available drug product. We also applied modern solid-state NMR (SS NMR) techniques, namely 2D (1)H DQ CRAMPS (Combined Rotation And Multiple Pulse Spectroscopy) and (1)H-(13)C on- and off-resonance CP (cross polarization) FSLG-HETCOR experiments, known for providing reliable information about (1)H-(1)H and (1)H-(13)C intra- and intermolecular proximities, in order to address polymorphism issues arising from the crystallization of a new form in the supercritical process. A new polymorph of didanosine was obtained from the supercritical antisolvent process and characterized by means of 1D and 2D multinuclear ((1)H, (13)C, (15)N) SS NMR. The particle size of the new crystal phase was reduced by varying the antisolvent density through a pressure increase. The structural differences between the commercial product and the SAS re-crystallized DDI are highlighted by X-ray diffractometry and well described by solid-state NMR. The carbon C6 (13)C chemical shift suggests that both commercial and re-crystallized didanosine samples are in the enol form. The analysis of homo- and heteronuclear proximities obtained by means of 2D NMR experiments shows that commercial and SAS re-crystallized DDI possess very similar molecular conformation and hydrogen bond network, but different packing. The new polymorph proved to be a metastable form at ambient conditions, showing higher solubility in water and lower stability to mechanical stress. 2009 Wiley-Liss, Inc. and the American Pharmacists Association

Dynamical spike solutions in a nonlocal model of pattern formation

NASA Astrophysics Data System (ADS)

Marciniak-Czochra, Anna; Härting, Steffen; Karch, Grzegorz; Suzuki, Kanako

2018-05-01

Coupling a reaction-diffusion equation with ordinary differential equa- tions (ODE) may lead to diffusion-driven instability (DDI) which, in contrast to the classical reaction-diffusion models, causes destabilization of both, constant solutions and Turing patterns. Using a shadow-type limit of a reaction-diffusion-ODE model, we show that in such cases the instability driven by nonlocal terms (a counterpart of DDI) may lead to formation of unbounded spike patterns.

A 2:1 AV rhythm: an adverse effect of a long AV delay during DDI pacing and its prevention by the ventricular intrinsic preference algorithm in DDD mode.

PubMed

Minamiguchi, Hitoshi; Oginosawa, Yasushi; Kohno, Ritsuko; Tamura, Masahito; Takeuchi, Masaaki; Otsuji, Yutaka; Abe, Haruhiko

2012-07-01

A 91-year-old woman received a dual-chamber pacemaker for sick sinus syndrome and intermittently abnormal atrioventricular (AV) conduction. The pacemaker was set in DDI mode with a 350-ms AV delay to preserve intrinsic ventricular activity. She complained of palpitation during AV sequential pacing. The electrocardiogram showed a 2:1 AV rhythm from 1:1 ventriculoatrial (VA) conduction during ventricular pacing in DDI mode with a long AV interval. After reprogramming of the pacemaker in DDD mode with a 250-ms AV interval and additional 100-ms prolongation of the AV interval by the ventricular intrinsic preference function, VA conduction disappeared and the patient's symptom were alleviated without increasing unnecessary right ventricular pacing. ©2011, The Authors. Journal compilation ©2011 Wiley Periodicals, Inc.

Patient- and physician-related risk factors for hyperkalaemia in potassium-increasing drug-drug interactions.

PubMed

Eschmann, Emmanuel; Beeler, Patrick E; Kaplan, Vladimir; Schneemann, Markus; Zünd, Gregor; Blaser, Jürg

2014-02-01

Hyperkalaemia due to potassium-increasing drug-drug interactions (DDIs) is a clinically important adverse drug event. The purpose of this study was to identify patient- and physician-related risk factors for the development of hyperkalaemia. The risk for adult patients hospitalised in the University Hospital Zurich between 1 December 2009 and 31 December 2011 of developing hyperkalaemia was correlated with patient characteristics, number, type and duration of potassium-increasing DDIs and frequency of serum potassium monitoring. The 76,467 patients included in this study were prescribed 8,413 potentially severe potassium-increasing DDIs. Patient-related characteristics associated with the development of hyperkalaemia were pulmonary allograft [relative risk (RR) 5.1; p < 0.0001), impaired renal function (RR 2.7; p < 0.0001), diabetes mellitus (RR 1.6; p = 0.002) and female gender (RR 1.5; p = 0.007). Risk factors associated with medication were number of concurrently administered potassium-increasing drugs (RR 3.3 per additional drug; p < 0.0001) and longer duration of the DDI (RR 4.9 for duration ≥6 days; p < 0.0001). Physician-related factors associated with the development of hyperkalaemia were undetermined or elevated serum potassium level before treatment initiation (RR 2.2; p < 0.001) and infrequent monitoring of serum potassium during a DDI (interval >48 h: RR 1.6; p < 0.01). Strategies for reducing the risk of hyperkalaemia during potassium-increasing DDIs should consider both patient- and physician-related risk factors.

Zidovudine (AZT) versus AZT plus didanosine (ddI) versus AZT plus zalcitabine (ddC) in HIV infected adults.

PubMed

Darbyshire, J; Foulkes, M; Peto, R; Duncan, W; Babiker, A; Collins, R; Hughes, M; Peto, T; Walker, A

2000-01-01

Zidovudine (AZT) monotherapy was the first antiretroviral drug to be tested widely. The next two drugs to be developed were didanosine (ddI) and zalcitabine (ddC). To assess the effects of zidovudine (AZT), zidovudine plus didanosine (ddI) and zidovudine plus zalcitabine (ddC) on HIV disease progression and survival. Investigators and pharmaceutical companies were contacted, and MEDLINE searches were supplemented by searching conference abstracts. Randomised controlled trials comparing any two of AZT plus ddI, AZT plus ddC or AZT alone in participants with or without AIDS which collected information on deaths and new AIDS events. Individual patient data with, wherever possible, follow-up obtained beyond that previously published were obtained and checked for internal consistency and consistency with any published reports; any apparent discrepancies were resolved with the trialists. Time to death and to disease progression (defined as a new AIDS-defining event or prior death) were analysed on an intention to treat basis, stratified to avoid direct comparisons between participants in different trials. Six trials were included in the meta-analysis. During a median follow-up of 29 months, 2904 individuals progressed, of whom 1850 died. The addition of ddI to AZT delayed both progression (RR 0.74; 95% CI 0.67 to 0.82, P<0.0001) and death (RR 0.72; 95% CI 0.64 to 0.82, P<0.0001). Likewise, the addition of ddC to AZT also delayed progression (RR 0. 86; 95% CI 0.78 to 0.94, P=0.001) and death (RR 0.87; 95% CI 0.77 to 0.98, P=0.02). After 3 years the estimated percentages alive and without a new AIDS event were 53% for AZT+ddI, 49% for AZT+ddC and 44% for AZT alone; the percentages alive were 68%, 63% and 59% respectively. Five of the six trials involved randomised comparisons of AZT+ddI versus AZT+ddC: in these, the AZT+ddI regimen had greater effects on disease progression (P=0.004) and death (P=0.009). The use of ddI and, to a lesser extent, ddC delayed both HIV disease progression and death, at least when added to AZT.

Double Electron Processes in Collisions of Partially Stripped Ions Cq+(q = 1-4) with Helium

NASA Astrophysics Data System (ADS)

Ding, Bao-Wei; Chen, Xi-Meng; Yu, De-Yang; Fu, Hong-Bin; Liu, Zhao-Yuan; Sun, Guang-Zhi; Liu, Yu-Wen; Lu, Yan-Xia; Xie, Jiang-Shan; Du, Juan; Gao, Zhi-Min; Chen, Lin; Cui, Ying; Shao, Jian-Xiong; He, Zi-Feng; Cai, Xiao-Hong

2007-01-01

The multi-electron processes are investigated for 17.9-120 keV/u C1+, 30-323 keV/u C2+, 120-438 keV/u C3+, 287-480 keV/u C4+ incident on a helium target. The cross-section ratios of double electron (DE) process to the total of the single electron (SE) and the double electron process (i.e. SE+DE), the direct double electron (DDI) to the direct single ionization (DSI) as well as the contributions of DDI to DE and of TI to DE are measured using coincidence techniques. The energy and charge state dependences of the measured cross-section ratios are studied and discussed.

The effect of the introduction of a nationwide DUR system where local DUR systems are operating--The Korean experience.

PubMed

Yang, Ju-Hyun; Kim, Mira; Park, Young-Taek; Lee, Eui-Kyung; Jung, Chai Young; Kim, Sukil

2015-11-01

Outpatient clinics in Korea usually have local DUR (drug utilisation review) systems, which are integrated with EMRs or health insurance claims submission systems. Whenever, the government announces a list of drug contraindications, each local DUR system loads the list and applies it in practice. In December 2010, a nationwide DUR system was introduced. This study is to investigate the impact of the nationwide DUR system on prescribing practices where local DUR systems are already operating. Between January 2009 and December 2012 the monthly number of drugs per prescription was retrieved from the health insurance claims data warehouse at the Health Insurance Review and Assessment (HIRA). The monthly proportions of 3 DDI (drug-drug interaction) pairs, 6 drug-age contraindications, and 3 drug-pregnancy contraindications from January 2007 to December 2012, at the outpatient clinic level, were also retrieved. An interrupted time series analysis was used for controlling government announcements of drug contraindications. There was no difference in the number of drugs per prescription before and after the introduction of the nationwide DUR system. Most proportions of the 3 DDI pairs, 6 drug-age contraindications, and 3 drug-pregnancy contraindications, were significantly reduced following the government announcement of drug contraindications in the short term and/or long term. The number of drugs per prescription was not related to the nationwide DUR introduction in places where local DUR systems are operating. The introduction of duplicate guidelines, in locations where the guidelines were already well followed, is considered to be the main reason for this. Furthermore, the Doctor's ignorance of alerts, and their continued substitution of regulated drugs, for non-regulated drugs, likely played a role in nullifying the effectiveness of the nationwide DUR system. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Lack of clinically important PK interaction between coformulated ledipasvir/sofosbuvir and rilpivirine/emtricitabine/tenofovir alafenamide.

PubMed

Custodio, Joseph M; Chuck, Susan K; Chu, Hoa; Cao, Huyen; Ma, Grace; Flaherty, John; Ling, John; Kearney, Brian P

2017-10-01

The drug-drug interaction (DDI) potential between the fixed-dose combinations of ledipasvir/sofosbuvir 90/400 mg for hepatitis C virus and emtricitabine/rilpivirine/tenofovir alafenamide (TAF) 200/25/25 mg for HIV was evaluated in a randomized, open-label, single-center, multiple-dose, 3-way, 6-sequence, crossover Phase 1 study in 42 healthy subjects. Emtricitabine/rilpivirine/TAF had no relevant effect on the pharmacokinetic parameters of maximum concentration [C max ] and area under the concentration versus time curve over the dosing interval [AUC tau ] for ledipasvir, sofosbuvir, and the metabolites GS-566500 and GS-331007. Ledipasvir/sofosbuvir had no effect on the C max and AUC tau for rilpivirine and emtricitabine. The C max and AUC tau of tenofovir, the major metabolite of TAF, were increased by 62% and 75%, respectively. However, the resulting absolute tenofovir exposures were markedly lower than the historical tenofovir exposures following tenofovir disoproxil fumarate (TDF) and, as such, were not considered to be clinically relevant. In contrast, additional adverse effect monitoring is recommended upon coadministration of ledipasvir and TDF due to elevated tenofovir exposures resulting from the DDI. This difference is explained by the fact that TAF 25 mg results in markedly lower (~90%) plasma tenofovir exposure compared to TDF 300 mg. Ledipasvir/sofosbuvir and emtricitabine/rilpivirine/TAF were generally well tolerated when administered alone or in combination. HIV/hepatitis C virus-coinfected patients can coadminister ledipasvir/sofosbuvir and emtricitabine/rilpivirine/TAF without dosage adjustments. © 2017 The Authors. Pharmacology Research & Perspectives published by John Wiley & Sons Ltd, British Pharmacological Society and American Society for Pharmacology and Experimental Therapeutics.

DNA-directed trypsin immobilization on a polyamidoamine dendrimer-modified capillary to form a renewable immobilized enzyme microreactor.

PubMed

Wu, Nan; Wang, Siming; Yang, Ye; Song, Jiayi; Su, Ping; Yang, Yi

2018-07-01

A novel type of trypsin capillary microreactor was developed based on a DNA-directed immobilization (DDI) technique applied to a fused-silica capillary modified with polyamidoamine (PAMAM) dendrimers. Trypsin binding to the inner wall of the capillary was confirmed by confocal laser scanning microscopy. The properties of the trypsin-DNA conjugated, PAMAM-modified capillary microreactor were investigated by monitoring hydrolysis of Nα-benzoyl- L -arginine ethyl ester. Through the hybridization and dehybridization of the DNA, the inner wall of the capillary functionalized with trypsin can be regenerated, thus indicating the renewability of this enzyme microreactor. In addition, these results demonstrated that introduction of PAMAM enabled higher amounts of trypsin to be immobilized, markedly improving the enzymolysis efficiency, compared with traditional modified capillaries. The digestion performance of the trypsin capillary microreactor was further evaluated by digesting cytochrome C, and a peptide numbers of 8, and a sequence coverage of 59% were obtained. This renewable and efficient immobilized trypsin capillary microreactor combines advantages of both DDI technology and PAMAM, and is potentially adaptable to high-throughput enzyme assays in biochemical and clinical research. Copyright © 2018. Published by Elsevier B.V.

Magic tilt angle for stabilizing two-dimensional solitons by dipole-dipole interactions

NASA Astrophysics Data System (ADS)

Chen, Xing-You; Chuang, You-Lin; Lin, Chun-Yan; Wu, Chien-Ming; Li, Yongyao; Malomed, Boris A.; Lee, Ray-Kuang

2017-10-01

In the framework of the Gross-Pitaevskii equation, we study the formation and stability of effectively two-dimensional solitons in dipolar Bose-Einstein condensates (BECs), with dipole moments polarized at an arbitrary angle θ relative to the direction normal to the system's plane. Using numerical methods and the variational approximation, we demonstrate that unstable Townes solitons, created by the contact attractive interaction, may be completely stabilized (with an anisotropic shape) by the dipole-dipole interaction (DDI), in the interval θcr<θ ≤π /2 . The stability boundary θcr weakly depends on the relative strength of the DDI, remaining close to the magic angle θm=arccos(1 /√{3 }) . The results suggest that DDIs provide a generic mechanism for the creation of stable BEC solitons in higher dimensions.

Separation of wind's influence on harmful cyanobacterial blooms.

PubMed

Wang, Hua; Zhang, Zhizhang; Liang, Dongfang; du, Hanbei; Pang, Yong; Hu, Kaimin; Wang, Jianjian

2016-07-01

Wind is an important physical factor involved in Harmful Cyanobacterial blooms (CyanoHABs). Its integrated influence was separated to three components: (a) Direct Disturbance Impact (DDI) on cyanbacterial proliferation, (b) Indirect Nutrient Impact (INI) by sediment release and (c) Direct Transportation Impact (DTI) by both gentle wind-induced surface drift and wave-generated Stokes drift. By the combination of field investigation, laboratory experiment and numerical simulation their individual contributions to the severe bloom event in May 2007 in Meiliang Bay, Lake Taihu, was explored. Wind synthetically made 10.5 percent promotion to the bloom on May 28, 2007, but the impact varied with locations. DTI was featured with the strongest contribution of wind's impacts on CyanoHABs, while INI stood at the lowest level and DDI played an intermediate role. From the point of whole Meiliang Bay, the influencing weights of DTI, DDI and INI were approximately 48.55%, 32.30% and 19.15% respectively. DTI exerted the higher promotion in the regions of middle-east (ME), southwest (SW) and southeast (SE), and its actual contribution rate on CyanoHABs ranged from 6.41% to 7.46%. Due to the background nutrient load, INI was characterized by a tiny effect with the contribution rate being 2.18% on average. From the south bay to the north, DDI was detected with a decreasing tendency, with the practical contribution rate generally falling from 4.13% to 2.7%. Copyright © 2016 Elsevier Ltd. All rights reserved.

Wide variation and patterns of physicians' responses to drug-drug interaction alerts.

PubMed

Cho, Insook; Lee, Yura; Lee, Jae-Ho; Bates, David W

2018-05-08

Providing physicians with alerts about potentially harmful drug-drug interactions (DDIs) is only moderately effective due to high alert override rates. To understand high override behavior on DDI alerts, we investigated how physicians respond to DDIs and their behavior patterns and variations. Retrospective system log data analysis and records review (sampling 2% of total overrides). A large tertiary academic hospital. About 560 physicians and their override responses to DDI alerts generated from 1 September to 31 December 2014. Not applicable. DDI alert frequency and override rate. We found significant variation in both the number of alerts and override rates at the levels of physicians, departments and drug-class pairs. Physician-level variations were wider for residents than for faculty staff (number of alerts: t = 254.17, P = 0.011; override rates: t = -4.77, P < 0.0001). Using the number of alerts and their override rate, we classified physicians into four groups: inexperienced incautious users, inexperienced cautious users, experienced cautious users and experienced incautious users. Medical department influenced both alert numbers and override rates. Nearly 90% of the overrides involved only five drug-class combinations, which had a wide range of appropriateness in the chart review. The variations at drug-class levels suggest issues with system design and the DDI rules. Department-level variation may be best addressed at the department level, and the rest of the variation appears related to individual physician responses, suggesting the need for interventions at an individual level.

[Dietary variety and diversity of Spanish children: Four Provinces Study].

PubMed

Royo-Bordonada, Miguel Angel; Gorgojo, Lydia; de Oya, Manuel; Garcés, Carmen; Rodríguez-Artalejo, Fernando; Rubio, Ramón; del Barrio, José Luis; Martín-Moreno, José María

2003-02-15

Diet variety is claimed for ensuring a healthy eating. Our objective was to analyze the relationship between the variety and diversity of the diet and its nutritional quality among Spanish children. Cross-sectional study where information on food and nutrition was obtained through a food frequency questionnaire. The sample included 1,112 children aged 6-7 years from 4 cities. Children were selected by random cluster-sampling in schools and stratified by sex and socioeconomic level. We calculated a diet variety index (DVI)--count of food items--and a diet diversity index (DDI)--count of food groups. To measure the overall diet quality, the Healthy Eating Index (HEI-f) was used. The percentage of children eating less than one daily food serving varied between 0% for the grain and 11.3% for the fruit groups. Diet variety and diversity were positively associated with the intake of fiber, vitamines B6 and E and folic acid, and the percentage of caloric intake resulting from polyinsaturated fatty acids and carbohydrates. In contrast, intakes of lipis and saturated fatty acids, vitamine C, sodium and calcium were all negatively associated with diet variety and diversity. Although both DVI and DDI were possitively associated with the HEI-f, the results from a regression model showed that it was only DDI that contributed significantly to the model fitting (p < 0.001). These results support the goodness of a varied diet that includes ingredients from different food groups and, at the same time, maintains the energy energy within recomended levels.

Insulin-like growth factor binding protein-1 levels are increased in patients with IgA nephropathy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tokunaga, Koki; Uto, Hirofumi, E-mail: hirouto@m2.kufm.kagoshima-u.ac.jp; Takami, Yoichiro

2010-08-20

Research highlights: {yields} IGFBP-1 mRNA over express in kidneys obtained from mice model of IgA nephropathy. {yields} Serum IGFBP-1 levels are high in patients with IgA nephropathy. {yields} Serum IGFBP-1 levels correlate with renal function and the severity of renal injury. -- Abstract: The mechanisms underlying the pathogenesis of immunoglobulin A (IgA) nephropathy (IgAN) are not well understood. In this study, we examined gene expression profiles in kidneys obtained from mice with high serum IgA levels (HIGA mice), which exhibit features of human IgAN. Female inbred HIGA, established from the ddY line, were used in these experiments. Serum IgA levels,more » renal IgA deposition, mesangial proliferation, and glomerulosclerosis were increased in 32-week-old HIGA mice in comparison to ddY animals. By microarray analysis, five genes were observed to be increased by more than 2.5-fold in 32-week-old HIGA in comparison to 16-week-old HIGA; these same five genes were decreased more than 2.5-fold in 32-week-old ddY in comparison to 16-week-old ddY mice. Of these five genes, insulin-like growth factor (IGF) binding protein (IGFBP)-1 exhibited differential expression between these mouse lines, as confirmed by quantitative RT-PCR. In addition, serum IGFBP-1 levels were significantly higher in patients with IgAN than in healthy controls. In patients with IgAN, these levels correlated with measures of renal function, such as estimated glomerular filtration rate (eGFR), but not with sex, age, serum IgA, C3 levels, or IGF-1 levels. Pathologically, serum IGFBP-1 levels were significantly associated with the severity of renal injury, as assessed by mesangial cell proliferation and interstitial fibrosis. These results suggest that increased IGFBP-1 levels are associated with the severity of renal pathology in patients with IgAN.« less

Clinical Drug-Drug Interaction Potential of BFE1224, Prodrug of Antifungal Ravuconazole, Using Two Types of Cocktails in Healthy Subjects.

PubMed

Ishii, Yasuyuki; Ito, Yuko; Matsuki, Shunji; Sanpei, Kasumi; Ogawa, Osamu; Takeda, Kenji; Schuck, Edgar L; Uemura, Naoto

2018-05-16

BFE1224, prodrug of ravuconazole, is a novel, once-daily, oral, triazole antifungal drug, and currently in development for the treatment of onychomycosis. The clinical drug-drug interaction (DDI) potential of BFE1224 with cytochrome P450 (CYP) and transporter was assessed by using two types of cocktails in healthy subjects in separate clinical studies. The CYP and transporter cocktails consisted of caffeine/tolbutamide/omeprazole/dextromethorphan/midazolam used in study 1 and digoxin/rosuvastatin used in study 2. In addition, repaglinide was separately administered to the same subjects in study 2. There were no major effects on the pharmacokinetics of CYP and transporter substrates, except for an approximate threefold increase in midazolam exposure after oral administration of BFE1224. The clinical DDIs of BFE1224 were mild for CYP3A and minor for other major CYPs (CYP1A2/2C8/2C9/2C19/2D6) as well as those of P-glycoprotein (P-gp), breast cancer resistance protein (BCRP), organic anion transporting polypeptide (OATP) 1B1, and OATP1B3. © 2018 The Authors. Clinical and Translational Science published by Wiley Periodicals, Inc. on behalf of American Society for Clinical Pharmacology and Therapeutics.

An attention-based effective neural model for drug-drug interactions extraction.

PubMed

Zheng, Wei; Lin, Hongfei; Luo, Ling; Zhao, Zhehuan; Li, Zhengguang; Zhang, Yijia; Yang, Zhihao; Wang, Jian

2017-10-10

Drug-drug interactions (DDIs) often bring unexpected side effects. The clinical recognition of DDIs is a crucial issue for both patient safety and healthcare cost control. However, although text-mining-based systems explore various methods to classify DDIs, the classification performance with regard to DDIs in long and complex sentences is still unsatisfactory. In this study, we propose an effective model that classifies DDIs from the literature by combining an attention mechanism and a recurrent neural network with long short-term memory (LSTM) units. In our approach, first, a candidate-drug-oriented input attention acting on word-embedding vectors automatically learns which words are more influential for a given drug pair. Next, the inputs merging the position- and POS-embedding vectors are passed to a bidirectional LSTM layer whose outputs at the last time step represent the high-level semantic information of the whole sentence. Finally, a softmax layer performs DDI classification. Experimental results from the DDIExtraction 2013 corpus show that our system performs the best with respect to detection and classification (84.0% and 77.3%, respectively) compared with other state-of-the-art methods. In particular, for the Medline-2013 dataset with long and complex sentences, our F-score far exceeds those of top-ranking systems by 12.6%. Our approach effectively improves the performance of DDI classification tasks. Experimental analysis demonstrates that our model performs better with respect to recognizing not only close-range but also long-range patterns among words, especially for long, complex and compound sentences.

Pathological lesions in the central nervous system and peripheral tissues of ddY mice with street rabies virus (1088 strain).

PubMed

Kimitsuki, Kazunori; Yamada, Kentaro; Shiwa, Nozomi; Inoue, Satoshi; Nishizono, Akira; Park, Chun-Ho

2017-06-10

Most studies on rabies virus pathogenesis in animal models have employed fixed rabies viruses, and the results of those employing street rabies viruses have been inconsistent. Therefore, to clarify the pathogenesis of street rabies virus (1088 strain) in mice, 10 6 focus forming units were inoculated into the right hindlimb of ddY mice (6 weeks, female). At 3 days postinoculation (DPI), mild inflammation was observed in the hindlimb muscle. At 5 DPI, ganglion cells in the right lumbosacral spinal dorsal root ganglia showed chromatolysis. Axonal degeneration and inflammatory cells increased with infection progress in the spinal dorsal horn and dorsal root ganglia. Right hindlimb paralysis was observed from 7 DPI, which progressed to quadriparalysis. However, no pathological changes were observed in the ventral horn and root fibers of the spinal cord. Viral antigen was first detected in the right hindlimb muscle at 3 DPI, followed by the right lumbosacral dorsal root ganglia, dorsal horn of spinal cord, left red nuclei, medulla oblongata and cerebral cortex (M1 area) at 5 DPI. These results suggested that the 1088 virus ascended the lumbosacral spinal cord via mainly afferent fibers at early stage of infection and moved to cerebral cortex (M1 area) using descending spinal tract. Additionally, we concluded that significant pathological changes in mice infected with 1088 strain occur in the sensory tract of the spinal cord; this selective susceptibility results in clinical features of the disease.

Relative contributions of the major human CYP450 to the metabolism of icotinib and its implication in prediction of drug-drug interaction between icotinib and CYP3A4 inhibitors/inducers using physiologically based pharmacokinetic modeling.

PubMed

Chen, Jia; Liu, Dongyang; Zheng, Xin; Zhao, Qian; Jiang, Ji; Hu, Pei

2015-06-01

Icotinib is an anticancer drug, but relative contributions of CYP450 have not been identified. This study was carried out to identify the contribution percentage of CYP450 to icotinib and use the results to develop a physiologically based pharmacokinetic (PBPK) model, which can help to predict drug-drug interaction (DDI). Human liver microsome (HLM) and supersome using relative activity factor (RAF) were employed to determine the relative contributions of the major human P450 to the net hepatic metabolism of icotinib. These values were introduced to develop a PBPK model using SimCYP. The model was validated by the observed data in a Phase I clinical trial in Chinese healthy subjects. Finally, the model was used to simulate the DDI with ketoconazole or rifampin. Final contribution of CYP450 isoforms determined by HLM showed that CYP3A4 provided major contributions to the metabolism of icotinib. The percentage contributions of the P450 to the net hepatic metabolism of icotinib were determined by HLM inhibition assay and RAF. The AUC ratio under concomitant use of ketoconazole and rifampin was 3.22 and 0.55, respectively. Percentage of contribution of CYP450 to icotinib metabolism was calculated by RAF. The model has been proven to fit the observed data and is used in predicting icotinib-ketoconazole/rifampin interaction.

Genetic backgrounds and redox conditions influence morphological characteristics and cell differentiation of osteoclasts in mice.

PubMed

Narahara, Shun; Matsushima, Haruna; Sakai, Eiko; Fukuma, Yutaka; Nishishita, Kazuhisa; Okamoto, Kuniaki; Tsukuba, Takayuki

2012-04-01

Osteoclasts (OCLs) are multinucleated giant cells and are formed by the fusion of mononuclear progenitors of monocyte/macrophage lineage. It is known that macrophages derived from different genetic backgrounds exhibit quite distinct characteristics of immune responses. However, it is unknown whether OCLs from different genetic backgrounds show distinct characteristics. In this study, we showed that bone-marrow macrophages (BMMs) derived from C57BL/6, BALB/c and ddY mice exhibited considerably distinct morphological characteristics and cell differentiation into OCLs. The differentiation of BMMs into OCLs was comparatively quicker in the C57BL/6 and ddY mice, while that of BALB/c mice was rather slow. Morphologically, ddY OCLs showed a giant cell with a round shape, C57BL/6 OCLs were of a moderate size with many protrusions and BALB/c OCLs had the smallest size with fewer nuclei. The intracellular signaling of differentiation and expression levels of marker proteins of OCLs were different in the respective strains. Treatment of BMMs from the three different strains with the reducing agent N-acetylcysteine (NAC) or with the oxidation agent hydrogen peroxide (H(2)O(2)) induced changes in the shape and sizes of the cells and caused distinct patterns of cell differentiation and survival. Thus, genetic backgrounds and redox conditions regulate the morphological characteristics and cell differentiation of OCLs.

Neural Tube Defects In Mice Exposed To Tap Water

PubMed Central

Mallela, Murali K; Werre, Stephen R; Hrubec, Terry C

2010-01-01

In May of 2006 we suddenly began to observe neural tube defects (NTDs) in embryos of untreated control mice. We hypothesized the mice were being exposed unknowingly to a teratogenic agent and investigated the cause. Our results suggested that NTDs were not resulting from bedding material, feed, strain or source of the mice. Additionally, mice were negative for routine and comprehensive screens of pathogens. To further test whether the NTDs resulted from infectious or genetic cause localized to our facility, we obtained three strains of timed pregnant mice from commercial suppliers located in 4 different states. All strains and sources of mice arrived in our laboratory with NTDs, implying that commercially available mice were possibly exposed to a teratogen prior to purchase. Our investigation eventually concluded that exposure to tap water was causing the NTDs. The incidence of NTDs was greatest in purchased mice provided tap water and lowest in purchased mice provided distilled deionized water (DDI). Providing mice DDI water for two generations (F2-DDI) eliminated the NTDs. When F2-DDI mice were provided tap water from three different urban areas prior to breeding, their offspring again developed NTDs. Increased length of exposure to tap water significantly increased the incidence of NTDs. These results indicate that a contaminant in municipal tap water is likely causing NTDs in mice. The unknown teratogen appears to have a wide geographic distribution but has not yet been identified. Water analysis is currently underway to identify candidate contaminants that might be responsible for the malformations. PMID:20549630

Perinatal dioxin exposure and the neurodevelopment of Vietnamese toddlers at 1 year of age.

PubMed

Pham, Tai The; Nishijo, Muneko; Nguyen, Anh Thi Nguyet; Tran, Nghi Ngoc; Hoang, Luong Van; Tran, Anh Hai; Nguyen, Trung Viet; Nishijo, Hisao

2015-12-01

Dioxin concentrations remain elevated in both the environment and in humans residing near former US Air Force bases in South Vietnam. This may potentially have adverse health effects, particularly on infant neurodevelopment. We followed 214 infants whose mothers resided in a dioxin-contaminated area in Da Nang, Vietnam, from birth until 1 year of age. Perinatal exposure to dioxins was estimated from toxic equivalent (TEQ) levels of polychlorinated dibenzodioxins and polychlorinated dibenzofurans (PCDDs/Fs-TEQ), and 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TetraCDD) concentrations in breast milk. In infants, daily dioxin intake (DDI) was used as an index of postnatal exposure through breastfeeding. Neurodevelopment of toddlers was assessed using the Bayley Scales of Infant and Toddler Development, Third Edition (Bayley-III). No significant differences in neurodevelopmental scores were exhibited for cognitive, language or motor functions between four exposure groups of PCDDs/Fs-TEQ or 2,3,7,8-TetraCDD. However, social-emotional scores were decreased in the high PCDDs/Fs-TEQ group and the high 2,3,7,8-TetraCDD group compared with those with mild exposure, after adjusting for confounding factors. Cognitive scores in the mild, moderate, and high DDI groups were significantly higher than those in low DDI group, but there were no differences in cognitive scores among the three higher DDI groups. These results suggest that perinatal exposure to dioxins may affect social-emotional development of 1-year-old toddlers, without diminishing global neurodevelopmental function. Crown Copyright © 2015. Published by Elsevier B.V. All rights reserved.

Unusual phonon behavior and ultra-low thermal conductance of monolayer InSe.

PubMed

Zhou, Hangbo; Cai, Yongqing; Zhang, Gang; Zhang, Yong-Wei

2017-12-21

Monolayer indium selenide (InSe) possesses numerous fascinating properties, such as high electron mobility, quantum Hall effect and anomalous optical response. However, its phonon properties, thermal transport properties and the origin of its structural stability remain unexplored. Using first-principles calculations, we show that the atoms in InSe are highly polarized and such polarization causes strong long-range dipole-dipole interaction (DDI). For acoustic modes, DDI is essential for maintaining its structural stability. For optical modes, DDI causes a significant frequency shift of its out-of-phase vibrations. Surprisingly, we observed that there were two isolated frequency regimes, which were completely separated from other frequency regimes with large frequency gaps. Within each frequency regime, only a single phonon mode exists. We further reveal that InSe possesses the lowest thermal conductance among the known two-dimensional materials due to the low cut-off frequency, low phonon group velocities and the presence of large frequency gaps. These unique behaviors of monolayer InSe can enable the fabrication of novel devices, such as thermoelectric module, single-mode phonon channel and phononic laser.

Disaster risk from a macroeconomic perspective: a metric for fiscal vulnerability evaluation.

PubMed

Cardona, Omar D; Ordaz, Mario G; Marulanda, Mabel C; Carreño, Martha L; Barbat, Alex H

2010-10-01

The Disaster Deficit Index (DDI) measures macroeconomic and financial risk in a country according to possible catastrophic scenario events. Extreme disasters can generate financial deficit due to sudden and elevated need of resources to restore affected inventories. The DDI captures the relationship between the economic loss that a country could experience when a catastrophic event occurs and the availability of funds to address the situation. The proposed model utilises the procedures of the insurance industry in establishing probable losses, based on critical impacts during a given period of exposure; for economic resilience, the model allows one to calculate the country's financial ability to cope with a critical impact. There are limitations and costs associated with access to resources that one must consider as feasible values according to the country's macroeconomic and financial conditions. This paper presents the DDI model and the results of its application to 19 countries of the Americas and aims to guide governmental decision-making in disaster risk reduction. © 2010 The Author(s). Journal compilation © Overseas Development Institute, 2010.

Anisotropic properties of phase separation in two-component dipolar Bose-Einstein condensates

NASA Astrophysics Data System (ADS)

Wang, Wei; Li, Jinbin

2018-03-01

Using Crank-Nicolson method, we calculate ground state wave functions of two-component dipolar Bose-Einstein condensates (BECs) and show that, due to dipole-dipole interaction (DDI), the condensate mixture displays anisotropic phase separation. The effects of DDI, inter-component s-wave scattering, strength of trap potential and particle numbers on the density profiles are investigated. Three types of two-component profiles are present, first cigar, along z-axis and concentric torus, second pancake (or blood cell), in xy-plane, and two non-uniform ellipsoid, separated by the pancake and third two dumbbell shapes.

Dioxin exposure in breast milk and infant neurodevelopment in Vietnam.

PubMed

Tai, Pham The; Nishijo, Muneko; Anh, Nguyen Thi Nguyet; Maruzeni, Shoko; Nakagawa, Hideaki; Van Luong, Hoang; Anh, Tran Hai; Honda, Ryumon; Kido, Teruhiko; Nishijo, Hisao

2013-09-01

Dioxin levels in the breast milk of mothers residing near hot spots of dioxin contamination areas in South Vietnam remain much higher than in unsprayed areas, suggesting that fetuses and breast-fed infants may be exposed to high levels of dioxins. The present study investigated the association of infant neurodevelopment in early infancy and dioxin exposure during the perinatal period. The study involved 216 mother-infant pairs living near the Da Nang airbase, a dioxin contaminated area in Vietnam. Mothers and infants were followed from birth until infants were 4 months old. Dioxin levels in breast milk were measured to estimate the perinatal dioxin exposure, including the infant daily dioxin intake (DDI) via breastfeeding. Infant neurodevelopmental parameters, including cognitive, language and motor domains were assessed at approximately 4 months using the Bayley Scales of Infant and Toddler Development, third edition (Bayley-III). The level of 2,3,7,8-tetrachlorodibenzo-p-dioxin and polychlorinated dibenzo-p-dioxins/furans-toxic equivalents in breast milk and the infant DDI showed significant inverse correlations with neurodevelopmental scores. When the subjects were divided into four groups according to dioxin levels in breast milk, the moderate and high DDI groups had significantly lower cognitive, composite motor and fine motor scores, and the high polychlorinated dibenzo-p-dioxins/furans-toxic equivalents group had significantly lower fine motor score than the low exposure group. For all domains, neurodevelopmental scores were decreased with increase in the level of 2,3,7,8-tetrachlorodibenzo-p-dioxin. The present study demonstrates a considerable impact of perinatal dioxin exposure on neurodevelopment in 4-month-old infants living in contaminated areas in Vietnam.

A strategy for early-risk predictions of clinical drug-drug interactions involving the GastroPlusTM DDI module for time-dependent CYP inhibitors.

PubMed

Sohlenius-Sternbeck, Anna-Karin; Meyerson, Gabrielle; Hagbjörk, Ann-Louise; Juric, Sanja; Terelius, Ylva

2018-04-01

1. A set of reference compounds for time-dependent inhibition (TDI) of cytochrome P450 with available literature data for k inact and K I was used to predict clinical implications using the GastroPlus TM software. Comparisons were made to in vivo literature interaction data. 2. The predicted AUC ratios (AUC +inhibitor /AUC control ) could be compared with the observed ratios from literature for all compounds with detailed information about in vivo administration, pharmacokinetics and in vivo interactions (N = 21). For this dataset, the difference between predicted and observed AUC ratios for interactions with midazolam was within twofold for all compounds except one (telaprevir, for which non-CYP-mediated metabolism likely plays a role after multiple dosing). 3. The sensitivity, specificity and accuracy of the GastroPlus TM predictions using a binary classification as no-to-weak interaction versus moderate-to-strong interaction for all compounds with available in vivo interaction data, were 80%, 82% and 81%, respectively (N = 31). 4. As a result of our evaluations of the DDI module in GastroPlus TM , we have implemented an early TDI risk assessment decision tree for our drug discovery projects involving in vitro screening and early GastroPlus TM predictions. Shifted IC 50 values are determined and k inact /K I estimated (by using a regression line established with in house-shifted IC 50 values and literature k inact /K I ratios), followed by GastroPlus TM predictions.

Safety analysis of the new synchronized and milwaukee B interchanges in comparison to existing designs.

PubMed

Molan, Amirarsalan Mehrara; Hummer, Joseph E

2017-12-01

Interchanges have high crash rates and large impacts on traffic operations. The main objective of this research is to analyze the safety performance of two new interchanges, the synchronized interchange and the Milwaukee B interchange. The primary method of study was microscopic simulation modeling using the Surrogate Safety Assessment Model (SSAM) program to estimate the quantity and type of conflicting interactions in each interchange. A comprehensive series of simulation scenarios were considered to include different conditions of traffic volumes, traffic turning ratios, traffic distribution, and heavy vehicles percentages. Afterward, outcomes were analyzed with two-way Analyses of Variance (ANOVAs) to compare the mean values of conflicts. Based on the results, the diverging diamond interchange (DDI) and Milwaukee B were the safest designs regarding observed conflicting interactions in the simulation models; however, the DDI did not seem as reliable from the viewpoint of wrong way movements. The new synchronized interchange, the parclo B, and the Milwaukee A (an existing interchange in Milwaukee, WI) showed the same rate of conflicts. The synchronized interchange may be advantageous because it was estimated to reduce the severity of crashes due to fewer crossing conflicts, a lower speed of conflicts, and a higher time to collision. The conventional diamond was the most dangerous design based on our measures. The DDI and the synchronized interchange look like plausible substitutes for reconstructing an unsafe diamond interchange due to the similarities in their required space. Copyright © 2017 Elsevier Ltd. All rights reserved.

Detecting signals of drug-drug interactions in a spontaneous reports database.

PubMed

Thakrar, Bharat T; Grundschober, Sabine Borel; Doessegger, Lucette

2007-10-01

The spontaneous reports database is widely used for detecting signals of ADRs. We have extended the methodology to include the detection of signals of ADRs that are associated with drug-drug interactions (DDI). In particular, we have investigated two different statistical assumptions for detecting signals of DDI. Using the FDA's spontaneous reports database, we investigated two models, a multiplicative and an additive model, to detect signals of DDI. We applied the models to four known DDIs (methotrexate-diclofenac and bone marrow depression, simvastatin-ciclosporin and myopathy, ketoconazole-terfenadine and torsades de pointes, and cisapride-erythromycin and torsades de pointes) and to four drug-event combinations where there is currently no evidence of a DDI (fexofenadine-ketoconazole and torsades de pointes, methotrexade-rofecoxib and bone marrow depression, fluvastatin-ciclosporin and myopathy, and cisapride-azithromycine and torsade de pointes) and estimated the measure of interaction on the two scales. The additive model correctly identified all four known DDIs by giving a statistically significant (P < 0.05) positive measure of interaction. The multiplicative model identified the first two of the known DDIs as having a statistically significant or borderline significant (P < 0.1) positive measure of interaction term, gave a nonsignificant positive trend for the third interaction (P = 0.27), and a negative trend for the last interaction. Both models correctly identified the four known non interactions by estimating a negative measure of interaction. The spontaneous reports database is a valuable resource for detecting signals of DDIs. In particular, the additive model is more sensitive in detecting such signals. The multiplicative model may further help qualify the strength of the signal detected by the additive model.

Detecting signals of drug–drug interactions in a spontaneous reports database

PubMed Central

Thakrar, Bharat T; Grundschober, Sabine Borel; Doessegger, Lucette

2007-01-01

Aims The spontaneous reports database is widely used for detecting signals of ADRs. We have extended the methodology to include the detection of signals of ADRs that are associated with drug–drug interactions (DDI). In particular, we have investigated two different statistical assumptions for detecting signals of DDI. Methods Using the FDA's spontaneous reports database, we investigated two models, a multiplicative and an additive model, to detect signals of DDI. We applied the models to four known DDIs (methotrexate-diclofenac and bone marrow depression, simvastatin-ciclosporin and myopathy, ketoconazole-terfenadine and torsades de pointes, and cisapride-erythromycin and torsades de pointes) and to four drug-event combinations where there is currently no evidence of a DDI (fexofenadine-ketoconazole and torsades de pointes, methotrexade-rofecoxib and bone marrow depression, fluvastatin-ciclosporin and myopathy, and cisapride-azithromycine and torsade de pointes) and estimated the measure of interaction on the two scales. Results The additive model correctly identified all four known DDIs by giving a statistically significant (P< 0.05) positive measure of interaction. The multiplicative model identified the first two of the known DDIs as having a statistically significant or borderline significant (P< 0.1) positive measure of interaction term, gave a nonsignificant positive trend for the third interaction (P= 0.27), and a negative trend for the last interaction. Both models correctly identified the four known non interactions by estimating a negative measure of interaction. Conclusions The spontaneous reports database is a valuable resource for detecting signals of DDIs. In particular, the additive model is more sensitive in detecting such signals. The multiplicative model may further help qualify the strength of the signal detected by the additive model. PMID:17506784

MinK-dependent internalization of the IKs potassium channel.

PubMed

Xu, Xianghua; Kanda, Vikram A; Choi, Eun; Panaghie, Gianina; Roepke, Torsten K; Gaeta, Stephen A; Christini, David J; Lerner, Daniel J; Abbott, Geoffrey W

2009-06-01

KCNQ1-MinK potassium channel complexes (4alpha:2beta stoichiometry) generate IKs, the slowly activating human cardiac ventricular repolarization current. The MinK ancillary subunit slows KCNQ1 activation, eliminates its inactivation, and increases its unitary conductance. However, KCNQ1 transcripts outnumber MinK transcripts five to one in human ventricles, suggesting KCNQ1 also forms other heteromeric or even homomeric channels there. Mechanisms governing which channel types prevail have not previously been reported, despite their significance: normal cardiac rhythm requires tight control of IKs density and kinetics, and inherited mutations in KCNQ1 and MinK can cause ventricular fibrillation and sudden death. Here, we describe a novel mechanism for this control. Whole-cell patch-clamping, confocal immunofluorescence microscopy, antibody feeding, biotin feeding, fluorescent transferrin feeding, and protein biochemistry techniques were applied to COS-7 cells heterologously expressing KCNQ1 with wild-type or mutant MinK and dynamin 2 and to native IKs channels in guinea-pig myocytes. KCNQ1-MinK complexes, but not homomeric KCNQ1 channels, were found to undergo clathrin- and dynamin 2-dependent internalization (DDI). Three sites on the MinK intracellular C-terminus were, in concert, necessary and sufficient for DDI. Gating kinetics and sensitivity to XE991 indicated that DDI decreased cell-surface KCNQ1-MinK channels relative to homomeric KCNQ1, decreasing whole-cell current but increasing net activation rate; inhibiting DDI did the reverse. The data redefine MinK as an endocytic chaperone for KCNQ1 and present a dynamic mechanism for controlling net surface Kv channel subunit composition-and thus current density and gating kinetics-that may also apply to other alpha-beta type Kv channel complexes.

Drug utilization, prescription errors and potential drug-drug interactions: an experience in rural Sri Lanka.

PubMed

Rathish, Devarajan; Bahini, Sivaswamy; Sivakumar, Thanikai; Thiranagama, Thilani; Abarajithan, Tharmarajah; Wijerathne, Buddhika; Jayasumana, Channa; Siribaddana, Sisira

2016-06-25

Prescription writing is a process which transfers the therapeutic message from the prescriber to the patient through the pharmacist. Prescribing errors, drug duplication and potential drug-drug interactions (pDDI) in prescriptions lead to medication error. Assessment of the above was made in prescriptions dispensed at State Pharmaceutical Corporation (SPC), Anuradhapura, Sri Lanka. A cross sectional study was conducted. Drugs were classified according to the WHO anatomical, therapeutic chemical classification system. A three point Likert scale, a checklist and Medscape online drug interaction checker were used to assess legibility, completeness and pDDIs respectively. Thousand prescriptions were collected. Majority were hand written (99.8 %) and from the private sector (73 %). The most frequently prescribed substance and subgroup were atorvastatin (4 %, n = 3668) and proton pump inhibitors (7 %, n = 3668) respectively. Out of the substances prescribed from the government and private sectors, 59 and 50 % respectively were available in the national list of essential medicines, Sri Lanka. Patients address (5 %), Sri Lanka Medical Council (SLMC) registration number (35 %), route (7 %), generic name (16 %), treatment symbol (48 %), diagnosis (41 %) and refill information (6 %) were seen in less than half of the prescriptions. Most were legible with effort (65 %) and illegibility was seen in 9 %. There was significant difference in omission and/or errors of generic name (P = 0.000), dose (P = 0.000), SLMC registration number (P = 0.000), and in evidence of pDDI (P = 0.009) with regards to the sector of prescribing. The commonest subgroup involved in duplication was non-steroidal anti-inflammatory drugs (NSAIDs) (43 %; 56/130). There were 1376 potential drug interactions (466/887 prescriptions). Most common pair causing pDDI was aspirin with losartan (4 %, n = 1376). Atorvastatin was the most frequently prescribed substance. Fifteen percent of the prescriptions originate from government sector. SLMC registration number and trade names were seen more in prescriptions originating from the private sector. Most prescriptions were legible with effort. NSAIDs were the commonest implicated in drug class duplication. Fifty three percent of prescriptions have pDDI.

Metabolism of a 5HT6 antagonist, 2-methyl-1-(phenylsulfonyl)-4-(piperazin-1-yl)-1H-benzo[d]imidazole (SAM-760): impact of sulfonamide metabolism on diminution of a ketoconazole mediated clinical drug-drug interaction.

PubMed

Sawant-Basak, Aarti; Obach, R Scott; Doran, Angela C; Lockwood, Peter; Schildknegt, Klaas; Gao, Hongying; Mancuso, Jessica; Tse, Susanna; Comery, Tom

2018-04-25

SAM-760, (2-methyl-1-(phenylsulfonyl)-4-(piperazin-1-yl)-1H-benzo[d]imidazole), a 5HT 6 antagonist, was investigated in humans for the treatment of Alzheimer's dementia. In liver microsomes and recombinant CYP450 isozymes, SAM-760 was predominantly metabolized by CYP3A (~85%). Based on these observations and an expectation of 5-fold magnitude of interaction with moderate to strong CYP3A inhibitors, a clinical DDI study was performed. In presence of ketoconazole, mean C max and AUC 0-inf of SAM-760 showed only a modest increase by 30% and 38%, respectively. In vitro investigation of this unexpectedly low interaction was undertaken using [ 14 C]SAM-760. Radiometric profiling in human hepatocytes, confirmed all oxidative metabolites observed previously with unlabeled SAM-760; however the pre-dominant radiometric peak was an unexpected polar metabolite which was insensitive to pan-CYP inhibitor, 1-aminobenzotriazole. In human hepatocytes, radiometric integration attributed 43% of total metabolism of SAM-760 to this non-CYP pathway. Using an authentic standard, this predominant metabolite was confirmed as benzenesulfinic acid. Additional investigation revealed that the benzenesulfinic acid metabolite may be a novel, non-enzymatic, thiol mediated reductive cleavage of aryl sulfonamide group of SAM-760. We also determined the relative contribution of P450 to metabolism of SAM-760 in human hepatocytes, by following the rate of formation of oxidative metabolites in presence and absence of P450 isoform specific inhibitors. P450 mediated oxidative metabolism of SAM-760 was still primarily attributed to CYP3A (33%), with minor contributions from CYP isoforms 2C19 and 2D6. Thus, disposition of [ 14 C]SAM-760 in human hepatocytes via novel sulfonamide metabolism and CYP3A verified the lower than expected clinical DDI when SAM-760 was co-administered with ketoconazole. The American Society for Pharmacology and Experimental Therapeutics.

Vortical structures for nanomagnetic memory induced by dipole-dipole interaction in monolayer disks

NASA Astrophysics Data System (ADS)

Liu, Zhaosen; Ciftja, Orion; Zhang, Xichao; Zhou, Yan; Ian, Hou

2018-05-01

It is well known that magnetic domains in nanodisks can be used as storage units for computer memory. Using two quantum simulation approaches, we show here that spin vortices on magnetic monolayer nanodisks, which are chirality-free, can be induced by dipole-dipole interaction (DDI) on the disk-plane. When DDI is sufficiently strong, vortical and anti-vortical multi-domain textures can be generated simultaneously. Especially, a spin vortex can be easily created and deleted through either external magnetic or electrical signals, making them ideal to be used in nanomagnetic memory and logical devices. We demonstrate these properties in our simulations.

Towards meaningful medication-related clinical decision support: recommendations for an initial implementation.

PubMed

Phansalkar, S; Wright, A; Kuperman, G J; Vaida, A J; Bobb, A M; Jenders, R A; Payne, T H; Halamka, J; Bloomrosen, M; Bates, D W

2011-01-01

Clinical decision support (CDS) can improve safety, quality, and cost-effectiveness of patient care, especially when implemented in computerized provider order entry (CPOE) applications. Medication-related decision support logic forms a large component of the CDS logic in any CPOE system. However, organizations wishing to implement CDS must either purchase the computable clinical content or develop it themselves. Content provided by vendors does not always meet local expectations. Most organizations lack the resources to customize the clinical content and the expertise to implement it effectively. In this paper, we describe the recommendations of a national expert panel on two basic medication-related CDS areas, specifically, drug-drug interaction (DDI) checking and duplicate therapy checking. The goals of this study were to define a starter set of medication-related alerts that healthcare organizations can implement in their clinical information systems. We also draw on the experiences of diverse institutions to highlight the realities of implementing medication decision support. These findings represent the experiences of institutions with a long history in the domain of medication decision support, and the hope is that this guidance may improve the feasibility and efficiency CDS adoption across healthcare settings.

Reduced physiologically-based pharmacokinetic model of repaglinide: impact of OATP1B1 and CYP2C8 genotype and source of in vitro data on the prediction of drug-drug interaction risk.

PubMed

Gertz, Michael; Tsamandouras, Nikolaos; Säll, Carolina; Houston, J Brian; Galetin, Aleksandra

2014-09-01

To investigate the effect of OATP1B1 genotype as a covariate on repaglinide pharmacokinetics and drug-drug interaction (DDIs) risk using a reduced physiologically-based pharmacokinetic (PBPK) model. Twenty nine mean plasma concentration-time profiles for SLCO1B1 c.521T>C were used to estimate hepatic uptake clearance (CLuptake) in different genotype groups applying a population approach in NONMEM v.7.2. Estimated repaglinide CLuptake corresponded to 217 and 113 μL/min/10(6) cells for SLCO1B1 c.521TT/TC and CC, respectively. A significant effect of OATP1B1 genotype was seen on CLuptake (48% reduction for CC relative to wild type). Sensitivity analysis highlighted the impact of CLmet and CLdiff uncertainty on the CLuptake optimization using plasma data. Propagation of this uncertainty had a marginal effect on the prediction of repaglinide OATP1B1-mediated DDI with cyclosporine; however, sensitivity of the predicted magnitude of repaglinide metabolic DDI was high. In addition, the reduced PBPK model was used to assess the effect of both CYP2C8*3 and SLCO1B1 c.521T>C on repaglinide exposure by simulations; power calculations were performed to guide prospective DDI and pharmacogenetic studies. The application of reduced PBPK model for parameter optimization and limitations of this process associated with the use of plasma rather than tissue profiles are illustrated.

Application of Physiologically Based Pharmacokinetic Modeling in Understanding Bosutinib Drug-Drug Interactions: Importance of Intestinal P-Glycoprotein.

PubMed

Yamazaki, Shinji; Loi, Cho-Ming; Kimoto, Emi; Costales, Chester; Varma, Manthena V

2018-05-08

Bosutinib is an orally available Src/Abl tyrosine kinase inhibitor indicated for the treatment of patients with Ph+ chronic myelogenous leukemia at a clinically recommended dose of 500 mg once daily. Clinical results indicated that increases in bosutinib oral exposures were supra-proportional at the lower doses (50 to 200 mg) and approximately dose-proportional at the higher doses (200 to 600 mg). Bosutinib is a substrate of CYP3A4 and P-glycoprotein and exhibits pH-dependent solubility with moderate intestinal permeability. These findings led us to investigate the factors influencing the underlying pharmacokinetic mechanisms of bosutinib with physiologically-based pharmacokinetic (PBPK) models. Our primary objectives were to: 1) refine the previously developed bosutinib PBPK model based on the latest oral bioavailability data and 2) verify the refined PBPK model with P-glycoprotein kinetics based on the bosutinib drug-drug interaction (DDI) results with ketoconazole and rifampin. Additionally, the verified PBPK model was applied to predict bosutinib DDIs with dual CYP3A/P-glycoprotein inhibitors. The results indicated that 1) the refined PBPK model adequately described the observed plasma concentration-time profiles of bosutinib and 2) the verified PBPK model reasonably predicted the effects of ketoconazole and rifampin on bosutinib exposures by accounting for intestinal P-gp inhibition/induction. These results suggested that bosutinib DDI mechanism could involve not only CYP3A4-mediated metabolism but also P-glycoprotein-mediated efflux on absorption. In summary, P-glycoprotein kinetics could constitute a critical element in the PBPK models to understand the pharmacokinetic mechanism of dual CYP3A/P-glycoprotein substrates such as bosutinib exhibiting nonlinear pharmacokinetics due largely to a saturation of intestinal P-glycoprotein-mediated efflux. The American Society for Pharmacology and Experimental Therapeutics.

Drug-Drug Interactions Between the Anti-Hepatitis C Virus 3D Regimen of Ombitasvir, Paritaprevir/Ritonavir, and Dasabuvir and Eight Commonly Used Medications in Healthy Volunteers.

PubMed

Polepally, Akshanth R; King, Jennifer R; Ding, Bifeng; Shuster, Diana L; Dumas, Emily O; Khatri, Amit; Chiu, Yi-Lin; Podsadecki, Thomas J; Menon, Rajeev M

2016-08-01

The three direct-acting antiviral regimen of ombitasvir/paritaprevir/ritonavir and dasabuvir (3D regimen) is approved for treatment of hepatitis C virus (HCV) genotype 1 infection. Drug-drug interaction (DDI) studies of the 3D regimen and commonly used medications were conducted in healthy volunteers to provide information on coadministering these medications with or without dose adjustments. Three phase I studies evaluated DDIs between the 3D regimen (ombitasvir/paritaprevir/ritonavir 25/150/100 mg once daily + dasabuvir 250 mg twice daily) and hydrocodone bitartrate/acetaminophen (5/300 mg), metformin hydrochloride (500 mg), diazepam (2 mg), cyclobenzaprine hydrochloride (5 mg), carisoprodol (250 mg), or sulfamethoxazole/trimethoprim (SMZ/TMP) (800/160 mg twice daily), all administered orally. DDI magnitude was determined using geometric mean ratios and 90 % confidence intervals for the maximum plasma concentration (C max) and area under the plasma concentration-time curve (AUC). Changes in exposures (C max and AUC geometric mean ratios) of acetaminophen, metformin, sulfamethoxazole, trimethoprim, and diazepam were ≤25 % upon coadministration with the 3D regimen. The C max and AUC of nordiazepam, an active metabolite of diazepam, increased by 10 % and decreased by 44 %, respectively. Exposures of cyclobenzaprine and carisoprodol decreased by ≤40 and ≤46 %, respectively, whereas exposures of hydrocodone increased up to 90 %. Ombitasvir, paritaprevir, ritonavir, and dasabuvir exposures changed by ≤25 %, except for a 37 % decrease in paritaprevir C max with metformin and a 33 % increase in dasabuvir AUC with SMZ/TMP. Acetaminophen, metformin, sulfamethoxazole, and trimethoprim can be coadministered with the 3D regimen without dose adjustment. Higher doses may be needed for diazepam, cyclobenzaprine, and carisoprodol based on clinical monitoring. A 50 % lower dose and/or clinical monitoring should be considered for hydrocodone. No dose adjustment is necessary for the 3D regimen.

A novel pyrazole derivative protects from ovariectomy-induced osteoporosis through the inhibition of NADPH oxidase

PubMed Central

Joo, Jung Hee; Huh, Jeong-Eun; Lee, Jee Hyun; Park, Doo Ri; Lee, Yoonji; Lee, Seul Gee; Choi, Sun; Lee, Hwa Jeong; Song, Seong-Won; Jeong, Yongmi; Goo, Ja-Il; Choi, Yongseok; Baek, Hye Kyung; Yi, Sun Shin; Park, Soo Jin; Lee, Ji Eun; Ku, Sae Kwang; Lee, Won Jae; Lee, Kee-In; Lee, Soo Young; Bae, Yun Soo

2016-01-01

Osteoclast cells (OCs) are differentiated from bone marrow-derived macrophages (BMMs) by activation of receptor activator of nuclear factor κB (NF-κB) ligand (RANKL). Activation of NADPH oxidase (Nox) isozymes is involved in RANKL-dependent OC differentiation, implicating Nox isozymes as therapeutic targets for treatment of osteoporosis. Here, we show that a novel pyrazole derivative, Ewha-18278 has high inhibitory potency on Nox isozymes. Blocking the activity of Nox with Ewha-18278 inhibited the responses of BMMs to RANKL, including reactive oxygen species (ROS) generation, activation of mitogen-activated protein (MAP) kinases and NF-κB, and OC differentiation. To evaluate the anti-osteoporotic function of Ewha-18278, the derivative was applied to estrogen-deficient ovariectomized (OVX) ddY mice. Oral administration of Ewha-18278 (10 mg/kg/daily, 4 weeks) into the mice recovered bone mineral density, trabecular bone volume, trabecular bone length, number and thickness, compared to control OVX ddY mice. Moreover, treatment of OVX ddY mice with Ewha-18278 increased bone strength by increasing cortical bone thickness. We provide that Ewha-18278 displayed Nox inhibition and blocked the RANKL-dependent cell signaling cascade leading to reduced differentiation of OCs. Our results implicate Ewha-18278 as a novel therapeutic agent for the treatment of osteoporosis. PMID:26975635

Abnormal brain aging as a radical-related disease: A new target for nuclear medicine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fujibayashi, Y.; Yamamoto, S.; Waki, A.

DNA damages caused by endogenously produced radicals are closely correlated with aging. Among them, mitochondrial DNA (mtDNA) deletions have been reported as a memory of DNA damage by oxygen radicals. In fact, clinical as well as experimental studies indicated the accumulation of deleted mtDNA in the brain, myocardium and son on, in aged subjects. In our previous work, radioiodinated radical trapping agent, p-iodophenyl-N-t-butylnitrone, and hypoxia imaging agent, Cu-62 diacetyl-bis-N-4-methyl-thiosemicarbazone have been developed for the diagnosis of radical-related diseases, such as ischemic, inflammation, cancer or aging. The aim of the present work was to evaluate these agents for brain aging studies.more » In our university, an unique animal model, a senescence accelerated model mouse (SAM), has been established. Among the various substrains, SAMP8 showing memory deterioration in its young age ({approximately}3 month) was basically evaluated as an abnormal brain aging model with mtDNA deletion. As controls, SAMR1 showing normal aging and ddY mice were used. MtDNA deletion n the brain was analyzed with polymerase-chain reaction (PCR) method, and relationship between mtDNA deletion and brain uptake of IPBN or Cu-62-ATSM was studied. In 1-3 month old SAMP8 brain, multiple mtDNa deletions were already found and their content was significantly higher than that of SAMR1 or age-matched ddY control. Thus, it was cleared that SAMP8 brain has high tendency to be attacked by endogenously produced oxygen radicals, possibly from its birth. Both IPBN and Cu-ATSM showed significantly higher accumulation in the SAMP8 brain than in the SAMR1 brain, indicating that these agents have high possibility for the early detection of abnormal brain aging as a radical-related disease.« less

P-gp, MRP2 and OAT1/OAT3 mediate the drug-drug interaction between resveratrol and methotrexate

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jia, Yongming

The purpose of present study was to investigate the effect of resveratrol (Res) on altering methotrexate (MTX) pharmacokinetics and clarify the related molecular mechanism. Res significantly increased rat intestinal absorption of MTX in vivo and in vitro. Simultaneously, Res inhibited MTX efflux transport in MDR1-MDCK and MRP2-MDCK cell monolayers, suggesting that the target of drug interaction was MDR1 and MRP2 in the intestine during the absorption process. Furthermore, there was a significant decrease in renal clearance of MTX after simultaneous intravenous administration. Similarly, MTX uptake was markedly inhibited by Res in rat kidney slices and hOAT1/3-HEK293 cell, indicating that OAT1more » and OAT3 were involved in the drug interaction in the kidney. Additionally, concomitant administration of Res decreased cytotoxic effects of MTX in hOAT1/3-HEK293 cells, and ameliorated nephrotoxicity caused by MTX in rats. Conversely, intestinal damage caused by MTX was not exacerbated after Res treatment. In conclusion, Res enhanced MTX absorption in intestine and decreased MTX renal elimination by inhibiting P-gp, MRP2, OAT1 and OAT3 in vivo and in vitro. Res improved MTX-induced renal damage without increasing intestinal toxicity. - Highlights: • DDI between MTX and Res will occur when they are co-administered. • The first targets of the DDI are P-gp and MRP2 located in intestine. • The second targets of the DDI are OAT1 and OAT3 in kidney. • Res improved MTX-induced renal damage without increasing intestinal toxicity.« less

User needs analysis and usability assessment of DataMed - a biomedical data discovery index.

PubMed

Dixit, Ram; Rogith, Deevakar; Narayana, Vidya; Salimi, Mandana; Gururaj, Anupama; Ohno-Machado, Lucila; Xu, Hua; Johnson, Todd R

2017-11-30

To present user needs and usability evaluations of DataMed, a Data Discovery Index (DDI) that allows searching for biomedical data from multiple sources. We conducted 2 phases of user studies. Phase 1 was a user needs analysis conducted before the development of DataMed, consisting of interviews with researchers. Phase 2 involved iterative usability evaluations of DataMed prototypes. We analyzed data qualitatively to document researchers' information and user interface needs. Biomedical researchers' information needs in data discovery are complex, multidimensional, and shaped by their context, domain knowledge, and technical experience. User needs analyses validate the need for a DDI, while usability evaluations of DataMed show that even though aggregating metadata into a common search engine and applying traditional information retrieval tools are promising first steps, there remain challenges for DataMed due to incomplete metadata and the complexity of data discovery. Biomedical data poses distinct problems for search when compared to websites or publications. Making data available is not enough to facilitate biomedical data discovery: new retrieval techniques and user interfaces are necessary for dataset exploration. Consistent, complete, and high-quality metadata are vital to enable this process. While available data and researchers' information needs are complex and heterogeneous, a successful DDI must meet those needs and fit into the processes of biomedical researchers. Research directions include formalizing researchers' information needs, standardizing overviews of data to facilitate relevance judgments, implementing user interfaces for concept-based searching, and developing evaluation methods for open-ended discovery systems such as DDIs. © The Author 2017. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.com

Potential for food-drug interactions by dietary phenolic acids on human organic anion transporters 1 (SLC22A6), 3 (SLC22A8), and 4 (SLC22A11).

PubMed

Wang, Li; Sweet, Douglas H

2012-10-15

Phenolic acids exert beneficial health effects such as anti-oxidant, anti-carcinogenic, and anti-inflammatory activities and show systemic exposure after consumption of common fruits, vegetables, and beverages. However, knowledge regarding which components convey therapeutic benefits and the mechanism(s) by which they cross cell membranes is extremely limited. Therefore, we determined the inhibitory effects of nine food-derived phenolic acids, p-coumaric acid, ferulic acid, gallic acid, gentisic acid, 4-hydroxybenzoic acid, protocatechuic acid, sinapinic acid, syringic acid, and vanillic acid, on human organic anion transporter 1 (hOAT1), hOAT3, and hOAT4. In the present study, inhibition of OAT-mediated transport of prototypical substrates (1 μM) by phenolic acids (100 μM) was examined in stably expressing cell lines. All compounds significantly inhibited hOAT3 transport, while just ferulic, gallic, protocatechuic, sinapinic, and vanillic acid significantly blocked hOAT1 activity. Only sinapinic acid inhibited hOAT4 (~35%). For compounds exhibiting inhibition > ~60%, known clinical plasma concentration levels and plasma protein binding in humans were examined to select compounds to evaluate further with dose-response curves (IC(50) values) and drug-drug interaction (DDI) index determinations. IC(50) values ranged from 1.24 to 18.08 μM for hOAT1 and from 7.35 to 87.36 μM for hOAT3. Maximum DDI indices for gallic and gentisic acid (≫0.1) indicated a very strong potential for DDIs on hOAT1 and/or hOAT3. This study indicates that gallic acid from foods or supplements, or gentisic acid from salicylate-based drug metabolism, may significantly alter the pharmacokinetics (efficacy and toxicity) of concomitant therapeutics that are hOAT1 and/or hOAT3 substrates. Copyright © 2012 Elsevier Inc. All rights reserved.

Satellite Navigation Backup Study

DTIC Science & Technology

2007-09-19

uro pe Eu rop...nd s To tal E uro pe Eu rop e A C Eu rop e G A Eu rop e G ov /St nd s D/D/I GPS/INS eLORAN Figure 6-14: Assessment Results – Solution Preference...LORAN for RNP 0.3 Approach: The Preliminary Conclusions of LORAN Integrity Performance Panel (LORIPP); Sherman Lo , Per Enge, Ben Peterson,

The drug-drug interaction potential of antiviral agents for the treatment of chronic hepatitis C infection.

PubMed

Garrison, Kimberly L; German, Polina; Mogalian, Erik; Mathias, Anita

2018-04-25

Several safe and highly-effective directly-acting antiviral drugs for chronic hepatitis C virus (HCV) have been developed and greatly increase the number of treatment options available to successfully treat HCV infection. However, as treatment regimens contain at least two drugs (e.g., sofosbuvir with daclatasvir, simeprevir, ledipasvir, or velpatasvir; elbasvir and grazoprevir) and up to five drugs (ombitasvir/paritaprevir/ritonavir+dasabuvir+ribavirin), the potential for drug-drug interactions (DDI) becomes an important consideration for HCV-infected individuals with comorbidities that require concomitant medications, such as HIV/HCV co-infection or immunosuppression following liver transplantation. This review details the pharmacokinetics and DDI potential of approved DAAs for the treatment of HCV infection. The American Society for Pharmacology and Experimental Therapeutics.

The tolerability and safety profile of patiromer: a novel polymer-based potassium binder for the treatment of hyperkalemia.

PubMed

Pitt, Bertram; Garza, Dahlia

2018-05-01

Hyperkalemia (HK) occurs often among patients with chronic kidney disease (CKD) and heart failure (HF) and those treated with renin-angiotensin-aldosterone system inhibitors (RAASI). Even small deviations from normal potassium levels carry increased risk of mortality. Patiromer is approved for treatment of HK and has been shown in clinical trials to reduce serum potassium among patients with HK and comorbid conditions. Areas covered: We review pooled data from two clinical trials of patiromer in patients with CKD and HK, safety of patiromer in special populations, drug-drug interaction (DDI) studies, and other studies in healthy volunteers. Expert opinion: Potassium must be maintained within a narrow range to avoid increased risk of mortality. Patients with CKD and HF and those receiving RAASI require careful monitoring of potassium levels. Patiromer effectively reduces serum potassium, and gastrointestinal adverse events (AEs) are the most common patiromer-associated AEs. Effective management of HK with patiromer may allow use of RAASI at optimal doses as recommended by treatment guidelines. Future research should examine the potential for potassium binders, including patiromer, to extend use of RAASI in appropriate patient populations.

Diverging diamond interchange performance evaluation (I-44 and Route 13)

DOT National Transportation Integrated Search

2011-02-01

Performance evaluation was conducted on the first diverging diamond interchange (DDI) or double : crossover interchange (DCD) constructed in the United States. This evaluation assessed traffic operations, safety and : public perceptions t...

Pharmacological considerations for azole antifungal drug management in cystic fibrosis lung transplant patients.

PubMed

Billaud, Eliane M; Guillemain, Romain; Berge, Maud; Amrein, Catherine; Lefeuvre, Sandrine; Louët, Agnès Lillo-Le; Boussaud, Véronique; Chevalier, Patrick

2010-11-01

This paper aims to present our experience in the pharmacological approach of the management of azole antifungal drugs in cystic fibrosis lung transplant patients. Cystic fibrosis (CF) lung transplantation is associated with multi-factorial care management, because of immunosuppressive requirements, risk of infections, frequency of gastro-oesophageal reflux disease, hepatic alterations and CF pharmacokinetics (PK) specificities that result in important PK variability. CF is associated with frequent colonization of the airways by filamentous fungi, especially by Aspergillus species. Today the antifungal therapeutic arsenal offers several possibilities for long-term oral therapy including azole drugs (itraconazole, voriconazole and posaconazole). Therefore, nephrotoxic amphotericin B should be avoided. The liver is important in the pharmacological profile of azole drugs, due to metabolic elimination, hepatotoxicity and PK drug-drug interaction (DDI) involving CYP3A4 metabolic inhibition. Targets for such DDI are numerous, but immunosuppressive drugs are of major concern, justifying combined therapeutic drug monitoring (TDM) of both azoles (inhibitors) and immunosuppressants (targets) on an individualized patient basis to adjust the coprescription quantitatively. The risk of long under-dosed periods, frequently addressed in this population, could justify, on a PK basis, the need for combination with an exclusive parenteral antifungal while waiting for azole relevant drug level. High PK variability, the risk of low exposure, therapeutic issues and DDI management in this complex underlying disease justify close monitoring with systematic combined TDM of azole and immunosuppressants, in case of coprescription.

Donor-derived infections in solid organ transplant patients: toward a holistic approach.

PubMed

Benamu, Esther; Wolfe, Cameron R; Montoya, José G

2017-08-01

Solid organ demand far exceeds organ supply. Strategies to increase the donor pool include the liberalization of selection criteria without increasing the risk of unexpected donor-derived infection (DDI), a rare complication of transplantation carrying high morbidity and mortality. We review the challenging aspects in the prevention of DDI, focusing on the complexities of data sharing and efficient communication and the role infectious diseases specialists play in the process. Advances in donor screening, transmission recognition and reporting allow for a better estimation of the risk of DDI. However, there is great variability in the frequency and methods with which organ procurement organizations report transmission events.Moreover, the Scientific Registry of Transplant Recipients provides limited donor and recipient outcome infectious diseases related data. Infectious disease contribution to the allocation process has been found to improve organ donation efficiency and communication between involved parties. Although communication gaps are strongly associated with infection transmission (relative risk 2.36%, confidence interval 1.48-3.78), effective communication minimizes or prevents infection in transplant recipients (X(1) 13.13, P = 0.0003). Prospective research is still required to define optimal screening protocols and further prevent transmission of infection. A holistic approach is likely to result in enhanced transplantation safety. Toward this goal, development of standards of investigation; improvement in reporting and data sharing; and strategies ensuring coordinated and rapid communication among parties involved in the allocation process need to be pursued.

Anti-climacterium effects of pomegranate concentrated solutions in ovariectomized ddY mice

PubMed Central

Kang, Su Jin; Choi, Beom Rak; Kim, Seung Hee; Yi, Hae Yeon; Park, Hye Rim; Song, Chang Hyun; Ku, Sae Kwang; Lee, Young Joon

2017-01-01

In the present study, the complex anti-climacterium potential of standardized pomegranate concentrated solution (PCS) was investigated using bilateral ovariectomy (OVX) female ddY mice. Changes in body weight and gain during experimental periods, food consumption, serum estradiol levels, total body and abdominal fat densities, abdominal fat pads, and uterus weights were observed, along with the histopathology of abdominal fat pads and uterus for anti-obesity and estrogenic effects. In addition, liver weights, serum aspartate aminotransferase (AST), alanine aminotransferase (ALT) levels, and histopathological inspections were performed to explore the hepato-protective effects. Serum total cholesterol (TC), low density lipoprotein (LDL), high density lipoprotein, and triglyceride (TG) levels were monitored for hypolipidemic effects with total body and femur mean bone mineral density (BMD), right femur wet, dry and ash weights, strength, serum osteocalcin, bone-specific alkaline phosphatase (bALP) contents, and histological and histomorphometrical analyses for anti-osteoporosis activity. As a result of OVX, notable increases in body weight and gains, food consumption, abdominal fat mass densities, weights of abdominal fat pads deposited in the abdominal cavity, and serum AST, ALT, TC, LDL, TG, and osteocalcin levels were observed, along with decreases in the uterus, liver, and femur weights, mean total body and femur BMD, femur strength, serum bALP, and estradiol levels. In addition, marked hypertrophic alterations in adipocytes located in the deposited abdominal fat pads, liver steatosis, uterine disused atrophic changes, and decreases in bone mass and structures of the femur were also observed in OVX control mice with significant increases in bone resorption markers based on histopathological and histomorphometrical analysis. However, these estrogen-deficient climacterium symptoms were significantly (P<0.05 or P<0.01) inhibited after 84 days of continuous treatment with estradiol and PCS (1, 2 and 4 ml/kg), respectively. The present results suggested that PCS was able to effectively inhibit or refine the climacterium symptoms, including obesity, hyperlipidemia, hepatic steatosis, and osteoporosis, induced by OVX in ddY mice. PMID:28413464

Accuracy and precision of four value-added blood glucose meters: the Abbott Optium, the DDI Prodigy, the HDI True Track, and the HypoGuard Assure Pro.

PubMed

Sheffield, Catherine A; Kane, Michael P; Bakst, Gary; Busch, Robert S; Abelseth, Jill M; Hamilton, Robert A

2009-09-01

This study compared the accuracy and precision of four value-added glucose meters. Finger stick glucose measurements in diabetes patients were performed using the Abbott Diabetes Care (Alameda, CA) Optium, Diagnostic Devices, Inc. (Miami, FL) DDI Prodigy, Home Diagnostics, Inc. (Fort Lauderdale, FL) HDI True Track Smart System, and Arkray, USA (Minneapolis, MN) HypoGuard Assure Pro. Finger glucose measurements were compared with laboratory reference results. Accuracy was assessed by a Clarke error grid analysis (EGA), a Parkes EGA, and within 5%, 10%, 15%, and 20% of the laboratory value criteria (chi2 analysis). Meter precision was determined by calculating absolute mean differences in glucose values between duplicate samples (Kruskal-Wallis test). Finger sticks were obtained from 125 diabetes patients, of which 90.4% were Caucasian, 51.2% were female, 83.2% had type 2 diabetes, and average age of 59 years (SD 14 years). Mean venipuncture blood glucose was 151 mg/dL (SD +/-65 mg/dL; range, 58-474 mg/dL). Clinical accuracy by Clarke EGA was demonstrated in 94% of Optium, 82% of Prodigy, 61% of True Track, and 77% of the Assure Pro samples (P < 0.05 for Optium and True Track compared to all others). By Parkes EGA, the True Track was significantly less accurate than the other meters. Within 5% accuracy was achieved in 34%, 24%, 29%, and 13%, respectively (P < 0.05 for Optium, Prodigy, and Assure Pro compared to True Track). Within 10% accuracy was significantly greater for the Optium, Prodigy, and Assure Pro compared to True Track. Significantly more Optium results demonstrated within 15% and 20% accuracy compared to the other meter systems. The HDI True Track was significantly less precise than the other meter systems. The Abbott Optium was significantly more accurate than the other meter systems, whereas the HDI True Track was significantly less accurate and less precise compared to the other meter systems.

Diverging diamond interchange : informational guide.

DOT National Transportation Integrated Search

2014-08-01

This document provides information and guidance on the Diverging Diamond Interchange (DDI). To the extent possible, the guide : addresses a variety of conditions found in the United States, to achieve designs suitable for a wide array of potential us...

Computational prediction of protein interactions related to the invasion of erythrocytes by malarial parasites.

PubMed

Liu, Xuewu; Huang, Yuxiao; Liang, Jiao; Zhang, Shuai; Li, Yinghui; Wang, Jun; Shen, Yan; Xu, Zhikai; Zhao, Ya

2014-11-30

The invasion of red blood cells (RBCs) by malarial parasites is an essential step in the life cycle of Plasmodium falciparum. Human-parasite surface protein interactions play a critical role in this process. Although several interactions between human and parasite proteins have been discovered, the mechanism related to invasion remains poorly understood because numerous human-parasite protein interactions have not yet been identified. High-throughput screening experiments are not feasible for malarial parasites due to difficulty in expressing the parasite proteins. Here, we performed computational prediction of the PPIs involved in malaria parasite invasion to elucidate the mechanism by which invasion occurs. In this study, an expectation maximization algorithm was used to estimate the probabilities of domain-domain interactions (DDIs). Estimates of DDI probabilities were then used to infer PPI probabilities. We found that our prediction performance was better than that based on the information of D. melanogaster alone when information related to the six species was used. Prediction performance was assessed using protein interaction data from S. cerevisiae, indicating that the predicted results were reliable. We then used the estimates of DDI probabilities to infer interactions between 490 parasite and 3,787 human membrane proteins. A small-scale dataset was used to illustrate the usability of our method in predicting interactions between human and parasite proteins. The positive predictive value (PPV) was lower than that observed in S. cerevisiae. We integrated gene expression data to improve prediction accuracy and to reduce false positives. We identified 80 membrane proteins highly expressed in the schizont stage by fast Fourier transform method. Approximately 221 erythrocyte membrane proteins were identified using published mass spectral datasets. A network consisting of 205 interactions was predicted. Results of network analysis suggest that SNARE proteins of parasites and APP of humans may function in the invasion of RBCs by parasites. We predicted a small-scale PPI network that may be involved in parasite invasion of RBCs by integrating DDI information and expression profiles. Experimental studies should be conducted to validate the predicted interactions. The predicted PPIs help elucidate the mechanism of parasite invasion and provide directions for future experimental investigations.

Improved Predictions of Drug-Drug Interactions Mediated by Time-Dependent Inhibition of CYP3A.

PubMed

Yadav, Jaydeep; Korzekwa, Ken; Nagar, Swati

2018-05-07

Time-dependent inactivation (TDI) of cytochrome P450s (CYPs) is a leading cause of clinical drug-drug interactions (DDIs). Current methods tend to overpredict DDIs. In this study, a numerical approach was used to model complex CYP3A TDI in human-liver microsomes. The inhibitors evaluated included troleandomycin (TAO), erythromycin (ERY), verapamil (VER), and diltiazem (DTZ) along with the primary metabolites N-demethyl erythromycin (NDE), norverapamil (NV), and N-desmethyl diltiazem (NDD). The complexities incorporated into the models included multiple-binding kinetics, quasi-irreversible inactivation, sequential metabolism, inhibitor depletion, and membrane partitioning. The resulting inactivation parameters were incorporated into static in vitro-in vivo correlation (IVIVC) models to predict clinical DDIs. For 77 clinically observed DDIs, with a hepatic-CYP3A-synthesis-rate constant of 0.000 146 min -1 , the average fold difference between the observed and predicted DDIs was 3.17 for the standard replot method and 1.45 for the numerical method. Similar results were obtained using a synthesis-rate constant of 0.000 32 min -1 . These results suggest that numerical methods can successfully model complex in vitro TDI kinetics and that the resulting DDI predictions are more accurate than those obtained with the standard replot approach.

Evaluation of a New Molecular Entity as a Victim of Metabolic Drug-Drug Interactions-an Industry Perspective.

PubMed

Bohnert, Tonika; Patel, Aarti; Templeton, Ian; Chen, Yuan; Lu, Chuang; Lai, George; Leung, Louis; Tse, Susanna; Einolf, Heidi J; Wang, Ying-Hong; Sinz, Michael; Stearns, Ralph; Walsky, Robert; Geng, Wanping; Sudsakorn, Sirimas; Moore, David; He, Ling; Wahlstrom, Jan; Keirns, Jim; Narayanan, Rangaraj; Lang, Dieter; Yang, Xiaoqing

2016-08-01

Under the guidance of the International Consortium for Innovation and Quality in Pharmaceutical Development (IQ), scientists from 20 pharmaceutical companies formed a Victim Drug-Drug Interactions Working Group. This working group has conducted a review of the literature and the practices of each company on the approaches to clearance pathway identification (fCL), estimation of fractional contribution of metabolizing enzyme toward metabolism (fm), along with modeling and simulation-aided strategy in predicting the victim drug-drug interaction (DDI) liability due to modulation of drug metabolizing enzymes. Presented in this perspective are the recommendations from this working group on: 1) strategic and experimental approaches to identify fCL and fm, 2) whether those assessments may be quantitative for certain enzymes (e.g., cytochrome P450, P450, and limited uridine diphosphoglucuronosyltransferase, UGT enzymes) or qualitative (for most of other drug metabolism enzymes), and the impact due to the lack of quantitative information on the latter. Multiple decision trees are presented with stepwise approaches to identify specific enzymes that are involved in the metabolism of a given drug and to aid the prediction and risk assessment of drug as a victim in DDI. Modeling and simulation approaches are also discussed to better predict DDI risk in humans. Variability and parameter sensitivity analysis were emphasized when applying modeling and simulation to capture the differences within the population used and to characterize the parameters that have the most influence on the prediction outcome. Copyright © 2016 by The American Society for Pharmacology and Experimental Therapeutics.

Mouse strain differences in immobility and sensitivity to fluvoxamine and desipramine in the forced swimming test: analysis of serotonin and noradrenaline transporter binding.

PubMed

Sugimoto, Yumi; Kajiwara, Yoshinobu; Hirano, Kazufumi; Yamada, Shizuo; Tagawa, Noriko; Kobayashi, Yoshiharu; Hotta, Yoshihiro; Yamada, Jun

2008-09-11

Strain differences in immobility time in the forced swimming test were investigated in five strains of mice, namely, ICR, ddY, C57BL/6, DBA/2 and BALB/c mice. There were significant strain differences. The immobility times of ICR, ddY and C57BL/6 mice were longer than those of DBA/2 and BALB/c mice. Immobility times were not significantly related to locomotor activity in these strains. There were also differences in sensitivity to the selective serotonin reuptake inhibitor (SSRI) fluvoxamine. In ICR, ddY and C57BL/6 mice, fluvoxamine did not affect immobility time, while it reduced the immobility time of DBA/2 and BALB/c mice dose-dependently. The noradrenaline reuptake inhibitor desipramine decreased immobility time in all strains of mice. Serotonin (5-HT) transporter binding in the brains of all five strains of mice was also investigated. Analysis of 5-HT transporter binding revealed significant strain differences, being lower in DBA/2 and BALB/c mice than in other strains of mice. The amount of 5-HT transporter binding was correlated to baseline immobility time. However, there was no significant relation between noradrenaline transporter binding and immobility time. These results suggest that the duration of baseline immobility depends on the levels of 5-HT transporter binding, leading to apparent strain differences in immobility time in the forced swimming test. Furthermore, differences in 5-HT transporter binding may cause variations in responses to fluvoxamine.

Dependency-based long short term memory network for drug-drug interaction extraction.

PubMed

Wang, Wei; Yang, Xi; Yang, Canqun; Guo, Xiaowei; Zhang, Xiang; Wu, Chengkun

2017-12-28

Drug-drug interaction extraction (DDI) needs assistance from automated methods to address the explosively increasing biomedical texts. In recent years, deep neural network based models have been developed to address such needs and they have made significant progress in relation identification. We propose a dependency-based deep neural network model for DDI extraction. By introducing the dependency-based technique to a bi-directional long short term memory network (Bi-LSTM), we build three channels, namely, Linear channel, DFS channel and BFS channel. All of these channels are constructed with three network layers, including embedding layer, LSTM layer and max pooling layer from bottom up. In the embedding layer, we extract two types of features, one is distance-based feature and another is dependency-based feature. In the LSTM layer, a Bi-LSTM is instituted in each channel to better capture relation information. Then max pooling is used to get optimal features from the entire encoding sequential data. At last, we concatenate the outputs of all channels and then link it to the softmax layer for relation identification. To the best of our knowledge, our model achieves new state-of-the-art performance with the F-score of 72.0% on the DDIExtraction 2013 corpus. Moreover, our approach obtains much higher Recall value compared to the existing methods. The dependency-based Bi-LSTM model can learn effective relation information with less feature engineering in the task of DDI extraction. Besides, the experimental results show that our model excels at balancing the Precision and Recall values.

Development of a Physiologically Based Pharmacokinetic Model for Sinogliatin, a First-in-Class Glucokinase Activator, by Integrating Allometric Scaling, In Vitro to In Vivo Exploration and Steady-State Concentration-Mean Residence Time Methods: Mechanistic Understanding of its Pharmacokinetics.

PubMed

Song, Ling; Zhang, Yi; Jiang, Ji; Ren, Shuang; Chen, Li; Liu, Dongyang; Chen, Xijing; Hu, Pei

2018-04-06

The objective of this study was to develop a physiologically based pharmacokinetic (PBPK) model for sinogliatin (HMS-5552, dorzagliatin) by integrating allometric scaling (AS), in vitro to in vivo exploration (IVIVE), and steady-state concentration-mean residence time (C ss -MRT) methods and to provide mechanistic insight into its pharmacokinetic properties in humans. Human major pharmacokinetic parameters were analyzed using AS, IVIVE, and C ss -MRT methods with available preclinical in vitro and in vivo data to understand sinogliatin drug metabolism and pharmacokinetic (DMPK) characteristics and underlying mechanisms. On this basis, an initial mechanistic PBPK model of sinogliatin was developed. The initial PBPK model was verified using observed data from a single ascending dose (SAD) study and further optimized with various strategies. The final model was validated by simulating sinogliatin pharmacokinetics under a fed condition. The validated model was applied to support a clinical drug-drug interaction (DDI) study design and to evaluate the effects of intrinsic (hepatic cirrhosis, genetic) factors on drug exposure. The two-species scaling method using rat and dog data (TS- rat,dog ) was the best AS method in predicting human systemic clearance in the central compartment (CL). The IVIVE method confirmed that sinogliatin was predominantly metabolized by cytochrome P450 (CYP) 3A4. The C ss -MRT method suggested dog pharmacokinetic profiles were more similar to human pharmacokinetic profiles. The estimated CL using the AS and IVIVE approaches was within 1.5-fold of that observed. The C ss -MRT method in dogs also provided acceptable prediction of human pharmacokinetic characteristics. For the PBPK approach, the 90% confidence intervals (CIs) of the simulated maximum concentration (C max ), CL, and area under the plasma concentration-time curve (AUC) of sinogliatin were within those observed and the 90% CI of simulated time to C max (t max ) was closed to that observed for a dose range of 5-50 mg in the SAD study. The final PBPK model was validated by simulating sinogliatin pharmacokinetics with food. The 90% CIs of the simulated C max , CL, and AUC values for sinogliatin were within those observed and the 90% CI of the simulated t max was partially within that observed for the dose range of 25-200 mg in the multiple ascending dose (MAD) study. This PBPK model selected a final clinical DDI study design with itraconazole from four potential designs and also evaluated the effects of intrinsic (hepatic cirrhosis, genetic) factors on drug exposure. Sinogliatin pharmacokinetic properties were mechanistically understood by integrating all four methods and a mechanistic PBPK model was successfully developed and validated using clinical data. This PBPK model was applied to support the development of sinogliatin.

Flai (fludarabine, cytarabine, idarubicin) plus low-dose Gemtuzumab Ozogamicin as induction therapy in CD33-positive AML: Final results and long term outcome of a phase II multicenter clinical trial.

PubMed

Candoni, Anna; Papayannidis, Cristina; Martinelli, Giovanni; Simeone, Erica; Gottardi, Michele; Iacobucci, Ilaria; Gherlinzoni, Filippo; Visani, Giuseppe; Baccarani, Michele; Fanin, Renato

2018-05-01

The aim of this prospective clinical trial was to evaluate the efficacy and safety of a combination of Gemtuzumab-Ozogamicin (GO) and FLAI scheme (fludarabine, cytarabine, idarubicin) as a first-line therapy in CD33 positive AML. We treated 130 patients, aged <65, with a median age of 52 years. FLAI-GO induction regimen included fludarabine (30 mg/sqm) and cytarabine (2 g/sqm) on days 1-5; idarubicin (10 mg/sqm) on days 1, 3, and 5; and GO (3 mg/sqm) on day 6. SCT was planned for all high-risk AML patients, after consolidation with intermediate doses of cytarabine and idarubicin and a high dose of cytarabine. CD33 expression exceeded 20% in all cases. Primary endpoints of the study included feasibility, overall response rate (ORR) and toxicity. Secondary endpoints included the evaluation of MRD by WT1 expression, feasibility and outcome of consolidation with SCT, overall survival (OS) and disease-free survival (DFS). After induction with FLAI-GO, complete remission (CR) rate was 82%. Four patients achieved partial remission (PR) and 12% were resistant (ORR 85%); death during induction (DDI) was 3%. The hematological and extra hematological toxicity of FLAI-GO was manageable; 45% of patients experienced transient and reversible GO infusion related adverse events. In the setting of patients who achieved a cytological CR after FLAI-GO, the mean of WT1 copies dropped from 8337±9936 copies/10 4 ABL (diagnosis) to 182 ± 436 copies after induction therapy (p = 0.0001) showing a very good disease debulking. After a median follow-up of 54 months, 67/130 (52%) patients were alive. The probability of 1, 2, and 5-year OS was 80%, 63%, and 52%, respectively. The probability of 1, 2, and 5-year DFS was 77%, 58%, and 52%, respectively. Allogeneic and autologous SCT was performed in 60 (46%) and 23 (18%) patients, respectively. In summary, the final results of this trial confirm that FLAI-GO is an active and safe treatment strategy for CD33-positive AML patients aged ≤ 65 years, allowing a high ORR, a good disease debulking, favorable safety profile, low DDI, and subsequent high SCT rate. The encouraging results of this trial, consolidated by a long follow-up, support the reintroduction of GO in clinical practice. © 2018 Wiley Periodicals, Inc.

Development of performance matrices for evaluating innovative intersections and interchanges.

DOT National Transportation Integrated Search

2015-09-01

Innovative intersections and interchanges, primarily Continuous Flow Intersection (CFI) and Diverging Diamond : Interchange (DDI), have seen an increase in numbers in the State of Utah over the past several years, making Utah a : leader in the countr...

Application of PBPK modelling in drug discovery and development at Pfizer.

PubMed

Jones, Hannah M; Dickins, Maurice; Youdim, Kuresh; Gosset, James R; Attkins, Neil J; Hay, Tanya L; Gurrell, Ian K; Logan, Y Raj; Bungay, Peter J; Jones, Barry C; Gardner, Iain B

2012-01-01

Early prediction of human pharmacokinetics (PK) and drug-drug interactions (DDI) in drug discovery and development allows for more informed decision making. Physiologically based pharmacokinetic (PBPK) modelling can be used to answer a number of questions throughout the process of drug discovery and development and is thus becoming a very popular tool. PBPK models provide the opportunity to integrate key input parameters from different sources to not only estimate PK parameters and plasma concentration-time profiles, but also to gain mechanistic insight into compound properties. Using examples from the literature and our own company, we have shown how PBPK techniques can be utilized through the stages of drug discovery and development to increase efficiency, reduce the need for animal studies, replace clinical trials and to increase PK understanding. Given the mechanistic nature of these models, the future use of PBPK modelling in drug discovery and development is promising, however, some limitations need to be addressed to realize its application and utility more broadly.

Lactobacillus helveticus-fermented milk improves learning and memory in mice.

PubMed

Ohsawa, Kazuhito; Uchida, Naoto; Ohki, Kohji; Nakamura, Yasunori; Yokogoshi, Hidehiko

2015-07-01

To investigate the effects of Calpis sour milk whey, a Lactobacillus helveticus-fermented milk product, on learning and memory. We evaluated improvement in scopolamine-induced memory impairment using the spontaneous alternation behaviour test, a measure of short-term memory. We also evaluated learning and working memory in mice using the novel object recognition test, which does not involve primary reinforcement (food or electric shocks). A total of 195 male ddY mice were used in the spontaneous alternation behaviour test and 60 in the novel object recognition test. Forced orally administered Calpis sour milk whey powder (200 and 2000 mg/kg) significantly improved scopolamine-induced cognitive impairments (P < 0.05 and P < 0.01, respectively) and object recognition memory (2000 mg/kg; P < 0.05). These results suggest that Calpis sour milk whey may be useful for the prevention of neurodegenerative disorders, such as Alzheimer's disease, and enhancing learning and memory in healthy human subjects; however, human clinical studies are necessary.

Activities of the human immunodeficiency virus type 1 (HIV-1) protease inhibitor nelfinavir mesylate in combination with reverse transcriptase and protease inhibitors against acute HIV-1 infection in vitro.

PubMed

Patick, A K; Boritzki, T J; Bloom, L A

1997-10-01

Nelfinavir mesylate (formerly AG1343) is a potent and selective, nonpeptidic inhibitor of human immunodeficiency virus type 1 (HIV-1) protease that was discovered by protein structure-based design methodologies. We evaluated the antiviral and cytotoxic effects of two-drug combinations of nelfinavir with the clinically approved antiretroviral therapeutics zidovudine (ZDV), lamivudine (3TC), dideoxycytidine (ddC; zalcitabine), stavudine (d4T), didanosine (ddI), indinavir, saquinavir, and ritonavir and a three-drug combination of nelfinavir with ZDV and 3TC against an acute HIV-1 strain RF infection of CEM-SS cells in vitro. Quantitative assessment of drug interaction was evaluated by a universal response surface approach (W. R. Greco, G. Bravo, and J. C. Parsons, Pharm. Rev. 47:331-385, 1995) and by the method of M. N. Prichard and C. Shipman (Antiviral Res. 14:181-206, 1990). Both analytical methods yielded similar results and showed that the two-drug combinations of nelfinavir with the reverse transcriptase inhibitors ZDV, 3TC, ddI, d4T, and ddC and the three-drug combination with ZDV and 3TC resulted in additive to statistically significant synergistic interactions. In a similar manner, the combination of nelfinavir with the three protease inhibitors resulted in additive (ritonavir and saquinavir) to slightly antagonistic (indinavir) interactions. In all combinations, minimal cellular cytotoxicity was observed with any drug alone and in combination. These results suggest that administration of combinations of the appropriate doses of nelfinavir with other currently approved antiretroviral therapeutic agents in vivo may result in enhanced antiviral activity with no associated increase in cellular cytotoxicity.

Activities of the human immunodeficiency virus type 1 (HIV-1) protease inhibitor nelfinavir mesylate in combination with reverse transcriptase and protease inhibitors against acute HIV-1 infection in vitro.

PubMed Central

Patick, A K; Boritzki, T J; Bloom, L A

1997-01-01

Nelfinavir mesylate (formerly AG1343) is a potent and selective, nonpeptidic inhibitor of human immunodeficiency virus type 1 (HIV-1) protease that was discovered by protein structure-based design methodologies. We evaluated the antiviral and cytotoxic effects of two-drug combinations of nelfinavir with the clinically approved antiretroviral therapeutics zidovudine (ZDV), lamivudine (3TC), dideoxycytidine (ddC; zalcitabine), stavudine (d4T), didanosine (ddI), indinavir, saquinavir, and ritonavir and a three-drug combination of nelfinavir with ZDV and 3TC against an acute HIV-1 strain RF infection of CEM-SS cells in vitro. Quantitative assessment of drug interaction was evaluated by a universal response surface approach (W. R. Greco, G. Bravo, and J. C. Parsons, Pharm. Rev. 47:331-385, 1995) and by the method of M. N. Prichard and C. Shipman (Antiviral Res. 14:181-206, 1990). Both analytical methods yielded similar results and showed that the two-drug combinations of nelfinavir with the reverse transcriptase inhibitors ZDV, 3TC, ddI, d4T, and ddC and the three-drug combination with ZDV and 3TC resulted in additive to statistically significant synergistic interactions. In a similar manner, the combination of nelfinavir with the three protease inhibitors resulted in additive (ritonavir and saquinavir) to slightly antagonistic (indinavir) interactions. In all combinations, minimal cellular cytotoxicity was observed with any drug alone and in combination. These results suggest that administration of combinations of the appropriate doses of nelfinavir with other currently approved antiretroviral therapeutic agents in vivo may result in enhanced antiviral activity with no associated increase in cellular cytotoxicity. PMID:9333041

Combustion Mechanisms of Wide Distribution Propellants

DTIC Science & Technology

1988-06-01

trimodal propellants were formulated. Each set contains an HTPB binder and duplicate formulations were made with either a IPDI or a DDI curative. The...Distinctive Mechanisms Previous studies [12,131 have shown that HTPB * propellants with wide AP distributions burn at rates much different than predictions...propellants. 17 .- = i.= i i i il =.. .l=limim mll ili= =.l i@ w. -’- 87% 400/20/ 3 MICRON,AP/ HTPB PROPELLANT 2.0 Z -1.0 --- 0--.-7- 0 CALCULATIONO0

Aminomethyl-Derived Beta Secretase (BACE1) Inhibitors: Engaging Gly230 without an Anilide Functionality

PubMed Central

2016-01-01

A growing subset of β-secretase (BACE1) inhibitors for the treatment of Alzheimer’s disease (AD) utilizes an anilide chemotype that engages a key residue (Gly230) in the BACE1 binding site. Although the anilide moiety affords excellent potency, it simultaneously introduces a third hydrogen bond donor that limits brain availability and provides a potential metabolic site leading to the formation of an aniline, a structural motif of prospective safety concern. We report herein an alternative aminomethyl linker that delivers similar potency and improved brain penetration relative to the amide moiety. Optimization of this series identified analogues with an excellent balance of ADME properties and potency; however, potential drug–drug interactions (DDI) were predicted based on CYP 2D6 affinities. Generation and analysis of key BACE1 and CYP 2D6 crystal structures identified strategies to obviate the DDI liability, leading to compound 16, which exhibits robust in vivo efficacy as a BACE1 inhibitor. PMID:27997172

Alprazolam as an in vivo probe for studying induction of CYP3A in cynomolgus monkeys.

PubMed

Ohtsuka, Tatsuyuki; Yoshikawa, Takahiro; Kozakai, Kazumasa; Tsuneto, Yumi; Uno, Yasuhiro; Utoh, Masahiro; Yamazaki, Hiroshi; Kume, Toshiyuki

2010-10-01

Induction of the cytochrome P450 (P450) enzyme is a major concern in the drug discovery processes. To predict the clinical significance of enzyme induction, it is helpful to investigate pharmacokinetic alterations of a coadministered drug in a suitable animal model. In this study, we focus on the induction of CYP3A, which is involved in the metabolism of approximately 50% of marketed drugs and is inducible in both the liver and intestine. As a marker substrate for CYP3A activity, alprazolam (APZ) was selected and characterized using recombinant CYP3A enzymes expressed in Escherichia coli. Both human CYP3A4 and its cynomolgus P450 ortholog predominantly catalyzed APZ 4-hydroxylation with sigmoidal kinetics. When administered intravenously and orally to cynomolgus monkeys, APZ had moderate clearance; its first-pass extraction ratio after oral dosing was estimated to be 0.09 in the liver and 0.45 in the intestine. Pretreatment with multiple doses of rifampicin (20 mg/kg p.o. for 5 days), a known CYP3A inducer, significantly decreased plasma concentrations of APZ after intravenous and oral administrations (0.5 mg/kg), and first-pass extraction ratios were increased to 0.39 in the liver and 0.63 in the intestine. The results were comparable to those obtained in clinical drug-drug interaction (DDI) reports related to CYP3A induction, although the rate of recovery of CYP3A activity seemed to be slower than rates estimated in clinical studies. In conclusion, pharmacokinetic studies using APZ as a probe in monkeys may provide useful information regarding the prediction of clinical DDIs due to CYP3A induction.

Stereoselective Inhibition of CYP2C19 and CYP3A4 by Fluoxetine and Its Metabolite: Implications for Risk Assessment of Multiple Time-Dependent Inhibitor Systems

PubMed Central

Lutz, Justin D.; VandenBrink, Brooke M.; Babu, Katipudi N.; Nelson, Wendel L.; Kunze, Kent L.

2013-01-01

Recent guidance on drug-drug interaction (DDI) testing recommends evaluation of circulating metabolites. However, there is little consensus on how to quantitatively predict and/or assess the risk of in vivo DDIs by multiple time-dependent inhibitors (TDIs) including metabolites from in vitro data. Fluoxetine was chosen as the model drug to evaluate the role of TDI metabolites in DDI prediction because it is a TDI of both CYP3A4 and CYP2C19 with a circulating N-dealkylated inhibitory metabolite, norfluoxetine. In pooled human liver microsomes, both enantiomers of fluoxetine and norfluoxetine were TDIs of CYP2C19, (S)-norfluoxetine was the most potent inhibitor with time-dependent inhibition affinity constant (KI) of 7 μM, and apparent maximum time-dependent inhibition rate (kinact,app) of 0.059 min−1. Only (S)-fluoxetine and (R)-norfluoxetine were TDIs of CYP3A4, with (R)-norfluoxetine being the most potent (KI = 8 μM, and kinact,app = 0.011 min−1). Based on in-vitro-to-in-vivo predictions, (S)-norfluoxetine plays the most important role in in vivo CYP2C19 DDIs, whereas (R)-norfluoxetine is most important in CYP3A4 DDIs. Comparison of two multiple TDI prediction models demonstrated significant differences between them in in-vitro-to-in-vitro predictions but not in in-vitro-to-in-vivo predictions. Inclusion of all four inhibitors predicted an in vivo decrease in CYP2C19 (95%) and CYP3A4 (60–62%) activity. The results of this study suggest that adequate worst-case risk assessment for in vivo DDIs by multiple TDI systems can be achieved by incorporating time-dependent inhibition by both parent and metabolite via simple addition of the in vivo time-dependent inhibition rate/cytochrome P450 degradation rate constant (λ/kdeg) values, but quantitative DDI predictions will require a more thorough understanding of TDI mechanisms. PMID:23785064

Application of quantitative time-lapse imaging (QTLI) for evaluation of Mrp2-based drug–drug interaction induced by liver metabolites

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nakanishi, Takeo; Ikenaga, Miho; Fukuda, Hajime

2012-09-01

We previously reported a quantitative time-lapse imaging (QTLI)-based analysis method to assess drug–drug interactions (DDI) at multidrug resistance-associated protein 2 (Mrp2) in rat sandwich-cultured hepatocyte (SCH) system, utilizing the fluorescent Mrp2 substrate, 5-(and 6)-carboxy-2′,7′-dichlorofluorescein (CDF). Here, we aimed to examine the feasibility of using QTLI to evaluate DDI involving drug metabolite(s) generated in hepatocytes. We used estradiol (E2) and bilirubin as model compounds; both are not substrates of MRP2, whereas their hepatic metabolites, estradiol-17β-glucuronide (E17G) or bilirubin glucuronides, are known to be its substrates as well as inhibitors. When rat SCHs were pre-exposed with E2, fluorescence of CDF accumulated inmore » bile canaliculi decreased depending upon both the duration of pre-exposure and the concentration of extracellular E2. The decrease corresponded with the increase in intracellular concentration of E17G in hepatocytes. Furthermore, cytotoxicity of vinblastine, a substrate of MRP2, was enhanced in SCHs treated with E2. Similarly, CDF accumulated in bile canaliculi was significantly reduced in rat SCHs pre-exposed with bilirubin. In conclusion, these results suggest that phase II biotransformation of a competitor is reflected in alteration of MRP2-mediated CDF transport detected in QTLI. The QTLI might provide a convenient platform to evaluate transporter-based DDIs involving hepatic metabolites of drug candidates without the need to identify the metabolites. -- Highlights: ► Mrp2-mediated CDF transport is inhibited by E2, but not E17G in vesicle study. ► Both E2 and E17G do not compromise CDF formation from CDFDA in hepatocytes. ► CDF accumulation in bile canaliculi is inhibited by E2 or E17G in QTLI. ► Increasing exposure to E2 decreases CDF accumulation in bile canaliculi in QTLI. ► QTLI is feasible to assess Mrp2-based DDI involving drug metabolite in hepatocytes.« less

Developing Difficult Dialogues: An Evaluation of Classroom Implementation

ERIC Educational Resources Information Center

Placier, Peggy; Kroner, Crystal; Burgoyne, Suzanne; Worthington, Roger

2012-01-01

The University of Missouri (MU) participated in the Ford Foundation's Difficult Dialogues Initiative (DDI) supporting faculty development projects at over 40 institutions of higher education from 2006-2010. This paper reports findings from an evaluation conducted with instructors who not only engaged in faculty development workshops but also…

Impact of Drug Metabolism/Pharmacokinetics and Their Relevance upon Taxus-based Drug Development.

PubMed

Hao, Da-Cheng; Ge, Guang-Bo; Wang, Ping; Yang, Ling

2018-05-22

Drug metabolism and pharmacokinetic (DMPK) studies of Taxus natural products, their semi-synthetic derivatives and analogs are indispensable in the optimization of lead compounds and clinical therapy. These studies can lead to development of new drug entities with improved absorption, distribution, metabolism, excretion and toxicity (ADME/T) profiles. To date, there have been no comprehensive reviews of the DMPK features of Taxus derived medicinal compounds.Natural and semi-synthetic taxanes may cause and could be affected by drug-drug interaction (DDI). Hence ADME/T studies of various taxane-containing formulations are important; to date these studies indicate that the role of cytochrome p450s and drug transporters is more prominent than phase II drug metabolizing enzymes. Mechanisms of taxane DMPK mediated by nuclear receptors, microRNAs, and single nucleotide polymorphisms are being revealed. Herein we review the latest knowledge on these topics, as well as the gaps in knowledge of the DMPK issues of Taxus compounds. DDIs significantly impact the PK/pharmacodynamics performance of taxanes and co-administered chemicals, which may inspire researchers to develop novel formula. While the ADME/T profiles of some taxanes are well defined, DMPK studies should be extended to more Taxus compounds, species, and Taxus -involved formulations, which would be streamlined by versatile omics platforms and computational analyses. Further biopharmaceutical investigations will be beneficial tothe translation of bench findings to the clinical applications. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Analysis of drug use in institutionalized individuals with intellectual disability and tube feeding.

PubMed

Joos, Elke; Mehuys, Els; Remon, Jean Paul; Van Winckel, Myriam; Boussery, Koen

2016-04-01

Little is known about the medication used by people with intellectual disabilities (ID) and enteral feeding tube (EFT). However, in light of the complexity associated with drug administration through EFT, data on medication use in this population may be helpful in the development of practical guidelines and staff training initiatives. A cross-sectional, observational study was conducted in six Belgian residential care facilities (RCFs) for individuals with ID. Anonymized medication records of all residents receiving chronic medication through EFT were collected (n = 156). All chronic drugs were categorized according to the ATC classification, and medication records were checked for potential major drug-drug interactions (DDI). The 156 residents used a total of 1029 chronic drugs via EFT, with a median of six drugs per resident (range 1-14). A total of 148 different drug molecules were identified, belonging to 38 main ATC therapeutic groups (ATC level 2). Antiepileptics, drugs for constipation and drugs for acid-related disorders were the most frequently used groups. Seventy-four of the 156 screened medication records (47%) contained at least one potential DDI; in total, 116 potential interactions were identified, which represent 38 different interacting drug pairs. This study describes medication use through EFT among people with ID in Belgian RCFs, with antiepileptics being the most frequently used group. Our study also demonstrated that a high number of drugs is administered through EFT, and that the number of potential DDIs is high. These observations warrant an increased attention for drug administration through the EFT in individuals with ID.

Merits and limitations of the mode switching rate stabilization pacing algorithms in the implantable cardioverter defibrillator.

PubMed

Dijkman, B; Wellens, H J

2001-09-01

The 7250 Jewel AF Medtronic model of ICD is the first implantable device in which both therapies for atrial arrhythmias and pacing algorithms for atrial arrhythmia prevention are available. Feasibility of that extensive atrial arrhythmia management requires correct and synergic functioning of different algorithms to control arrhythmias. The ability of the new pacing algorithms to stabilize the atrial rate following termination of treated atrial arrhythmias was evaluated in the marker channel registration of 600 spontaneously occurring episodes in 15 patients with the Jewel AF. All patients (55+/-15 years) had structural heart disease and documented atrial and ventricular arrhythmias. Dual chamber rate stabilization pacing was present in 245 (41 %) of episodes following arrhythmia termination and was a part of the mode switching operation during which pacing was provided in the dynamic DDI mode. This algorithm could function as the atrial rate stabilization pacing only when there was a slow spontaneous atrial rhythm or in presence of atrial premature beats conducted to the ventricles with a normal AV time. In case of atrial premature beats with delayed or absent conduction to the ventricles and in case of ventricular premature beats, the algorithm stabilized the ventricular rate. The rate stabilization pacing in DDI mode during sinus rhythm following atrial arrhythmia termination was often extended in time due to the device-based definition of arrhythmia termination. This was also the case in patients, in whom the DDD mode with true atrial rate stabilization algorithm was programmed. The rate stabilization algorithms in the Jewel AF applied after atrial arrhythmia termination provide pacing that is not based on the timing of atrial events. Only under certain circumstances the algorithm can function as atrial rate stabilization pacing. Adjustments in availability and functioning of the rate stabilization algorithms might be of benefit for the clinical performance of pacing as part of device therapy for atrial arrhythmias.

Evaluation of Drug-Drug Interaction Potential Between Sacubitril/Valsartan (LCZ696) and Statins Using a Physiologically Based Pharmacokinetic Model.

PubMed

Lin, Wen; Ji, Tao; Einolf, Heidi; Ayalasomayajula, Surya; Lin, Tsu-Han; Hanna, Imad; Heimbach, Tycho; Breen, Christopher; Jarugula, Venkateswar; He, Handan

2017-05-01

Sacubitril/valsartan (LCZ696) has been approved for the treatment of heart failure. Sacubitril is an in vitro inhibitor of organic anion-transporting polypeptides (OATPs). In clinical studies, LCZ696 increased atorvastatin C max by 1.7-fold and area under the plasma concentration-time curve by 1.3-fold, but had little or no effect on simvastatin or simvastatin acid exposure. A physiologically based pharmacokinetics modeling approach was applied to explore the underlying mechanisms behind the statin-specific LCZ696 drug interaction observations. The model incorporated OATP-mediated clearance (CL int,T ) for simvastatin and simvastatin acid to successfully describe the pharmacokinetic profiles of either analyte in the absence or presence of LCZ696. Moreover, the model successfully described the clinically observed drug effect with atorvastatin. The simulations clarified the critical parameters responsible for the observation of a low, yet clinically relevant, drug-drug interaction DDI between sacubitril and atorvastatin and the lack of effect with simvastatin acid. Atorvastatin is administered in its active form and rapidly achieves C max that coincide with the low C max of sacubitril. In contrast, simvastatin requires a hydrolysis step to the acid form and therefore is not present at the site of interactions at sacubitril concentrations that are inhibitory. Similar models were used to evaluate the drug-drug interaction risk for additional OATP-transported statins which predicted to maximally result in a 1.5-fold exposure increase. Copyright © 2017. Published by Elsevier Inc.

Potential role of pre-existing blood vessels for vascularization and mineralization of osteochondral grafts: an intravital microscopic study in mice.

PubMed

Rothenfluh, Dominique A; Demhartner, Thomas J; Fraitzl, Christian R; Cecchini, Marco G; Ganz, Reinhold; Leunig, Michael

2004-06-01

The aim of this study was to develop an experimental model that allows to elude the potential role of the preexisting graft microvasculature for vascularization and mineralization of osteochondral grafts. For that purpose, the II-IV metatarsals of fetal DDY-mice known to be nonvascularized at day 16 of gestation (M16) but vascularized at day 18 (M18) were freshly transplanted into dorsal skin fold chambers of adult DDY mice. Using intravital microscopy angiogenesis, leukocyte-endothelium interaction and mineralization were assessed for 12 days. Angiogenesis occurred at 32 hours in M18, but not before 57 hours in M16 (p = 0.002), with perfusion of these vessels at 42 hours (p = 0.005) and 65 hours (p = 0.1), respectively. Vessels reached a density three times as high as that of the recipient site at day 6, remaining constant until day 12 in M18, whereas in M16 vascular density increased from day 6 and reached that of M18 at day 12 (p = 0.04). Leukocyte-endothelium interaction showed sticker counts elevated by a factor of 4-5 in M18 as compared to M16. Mineralization of osteochondral grafts did not differ between M16 and M18, which significantly increased in both groups throughout the observation period. We propose the faster kinetics in the angiogenic response to M18 and the elevated counts of sticking leukocytes to rest on the potential of establishing end-to-end anastomoses (inosculation) of the vascularized graft with recipient vessels.

Peroxisome proliferator activated receptor alpha regulates a male-specific cytochrome P450 in mouse liver.

PubMed

Jeffery, Brett; Choudhury, Agharul I; Horley, Neill; Bruce, Mary; Tomlinson, Simon R; Roberts, Ruth A; Gray, Tim J B; Barrett, David A; Shaw, P Nicholas; Kendall, David; Bell, David R

2004-09-15

We set out to find if the strain-specific, male-specific hepatic expression of Cyp4a protein in mouse was due to expression of Cyp4a12 and to understand the genetic basis for reported differences in expression. 12-Lauric acid hydroxylase (LAH) activity was found to show higher levels in male ddY, but not C57Bl/6, mouse liver microsomes. The expression of Cyp4a12 mRNA was studied using RNAase protection assays in male and female liver and kidney of nine mouse strains. Cyp4a12 was found to be highly expressed in male liver and kidney, but at much lower levels in female liver and kidney, in all strains studied. Western blotting with an antibody specific for Cyp4a12 confirmed that Cyp4a12 was expressed in a male specific fashion in C57Bl/6 mouse liver. RNAase protection analysis for Cyp4a10 and 14 in ddY mice revealed that neither of these genes showed male-specific expression. To further investigate genetic factors that control male-specific Cyp4a12 expression, PPARalpha+/+ and -/- mice were studied, showing that total P450 and 12-LAH activity was male-specific in +/+, but not -/- mice. RNAase protection assays were used to confirm that Cyp4a12 was lower in -/- mice. However, the male-specific Slp and MUP-1 genes retained hepatic male-specific levels of expression in +/+ and -/- mice, showing that the decrease in Cyp4a12 was not a general effect on male-specific expression. Thus, PPARalpha has a specific effect on constitutive expression of Cyp4a12.

Prevalence of potentially serious drug-drug interactions among South African elderly private health sector patients using the Mimica Matanović/Vlahović-Palčevski protocol.

PubMed

van Heerden, Julandi A; Burger, Johanita R; Gerber, Jan J; Vlahović-Palčevski, Vera

2018-04-01

To determine the prevalence of potentially serious drug-drug interactions (DDIs) and their relationship with gender and age, among elderly in South Africa. A cross-sectional study was conducted using pharmaceutical claims data for 2013, for a total of 103 420 medical scheme beneficiaries' ≥65 years. All medications dispensed within one calendar month where the days' supply of medication dispensed overlapped, were grouped as one prescription. DDIs per prescription were then identified using the Mimica Matanović/Vlahović-Palčevski DDI protocol. Results were interpreted using effect sizes, that is Cramér's V, Cohen's d and Cohen's ƒ 2 . A total of 331 659 DDIs were identified on 235 870 (25.8%, N = 912 713) prescriptions (mean 0.36 (SD 0.7) (95% CI, 0.36 to 0.37)). Women encountered 63.5% of all DDIs. Effect sizes for the association between DDIs and age group (Cramér's V = 0.06), and gender (Cramér's V = 0.05) was negligible. There was no difference between men and women regarding the mean number of DDIs identified per prescription (Cohen's d = 0.10). The number of medicine per prescription (ƒ 2 = 0.51) was the biggest predictor of the DDIs. The most frequent interacting drug combinations were between central nervous system medicines (30.6%). Our study is the first to report the prevalence of potentially serious DDIs among an elderly population in the South African private health sector utilising the Mimica Matanović/Vlahović-Palčevski DDI protocol. Overall, we identified DDIs in approximately 26% of the prescriptions in our study. Age and gender were not found to be predictors of potentially serious DDIs. © 2017 Royal Pharmaceutical Society.

Simulation and Prediction of the Drug-Drug Interaction Potential of Naloxegol by Physiologically Based Pharmacokinetic Modeling.

PubMed

Zhou, D; Bui, K; Sostek, M; Al-Huniti, N

2016-05-01

Naloxegol, a peripherally acting μ-opioid receptor antagonist for the treatment of opioid-induced constipation, is a substrate for cytochrome P450 (CYP) 3A4/3A5 and the P-glycoprotein (P-gp) transporter. By integrating in silico, preclinical, and clinical pharmacokinetic (PK) findings, minimal and full physiologically based pharmacokinetic (PBPK) models were developed to predict the drug-drug interaction (DDI) potential for naloxegol. The models reasonably predicted the observed changes in naloxegol exposure with ketoconazole (increase of 13.1-fold predicted vs. 12.9-fold observed), diltiazem (increase of 2.8-fold predicted vs. 3.4-fold observed), rifampin (reduction of 76% predicted vs. 89% observed), and quinidine (increase of 1.2-fold predicted vs. 1.4-fold observed). The moderate CYP3A4 inducer efavirenz was predicted to reduce naloxegol exposure by ∼50%, whereas weak CYP3A inhibitors were predicted to minimally affect exposure. In summary, the PBPK models reasonably estimated interactions with various CYP3A modulators and can be used to guide dosing in clinical practice when naloxegol is coadministered with such agents. © 2016 The Authors CPT: Pharmacometrics & Systems Pharmacology published by Wiley Periodicals, Inc. on behalf of American Society for Clinical Pharmacology and Therapeutics.

Human health risk assessment of polycyclic aromatic hydrocarbons (PAHs) in smoked fish species from markets in Southern Nigeria.

PubMed

Tongo, Isioma; Ogbeide, Ozekeke; Ezemonye, Lawrence

2017-01-01

Polycyclic Aromatic Hydrocarbons (PAHs) levels in four commonly consumed smoked fish species from markets in Southern Nigeria were assessed to evaluate possible human health risks associated with consumption. Varying levels of PAH congeners were observed in the fish tissues with the highest total concentration of PAHs in Scomber scombrus . High concentrations of benzo(a)pyrene was observed in Clarias gariepinus and Ethmalosa fimbriata with values above the guideline value of 0.05 mg/kg. The Dietary Daily Intake (DDI) value for total PAHs (∑PAHs) was highest for S. scombrus while the DDI value for the total carcinogenic PAHs (∑CPAHs) was highest for E. fimbriata . Carcinogenic human health risk assessment using carcinogenic toxic equivalents (TEQ), indicated that consumption of E. fimbriata has a higher potential to cause carcinogenic risks. TEQ values for all the fish species were however, below the estimated screening value (SV) of 3.556 mg/kg, while the estimated cumulative excess cancer risk (ECR) for E. fimbriata and C. gariepinus and PAH4 index for all the assessed fish species exceeded threshold values indicating potential carcinogenic risk from consumption.

Multichannel Convolutional Neural Network for Biological Relation Extraction.

PubMed

Quan, Chanqin; Hua, Lei; Sun, Xiao; Bai, Wenjun

2016-01-01

The plethora of biomedical relations which are embedded in medical logs (records) demands researchers' attention. Previous theoretical and practical focuses were restricted on traditional machine learning techniques. However, these methods are susceptible to the issues of "vocabulary gap" and data sparseness and the unattainable automation process in feature extraction. To address aforementioned issues, in this work, we propose a multichannel convolutional neural network (MCCNN) for automated biomedical relation extraction. The proposed model has the following two contributions: (1) it enables the fusion of multiple (e.g., five) versions in word embeddings; (2) the need for manual feature engineering can be obviated by automated feature learning with convolutional neural network (CNN). We evaluated our model on two biomedical relation extraction tasks: drug-drug interaction (DDI) extraction and protein-protein interaction (PPI) extraction. For DDI task, our system achieved an overall f -score of 70.2% compared to the standard linear SVM based system (e.g., 67.0%) on DDIExtraction 2013 challenge dataset. And for PPI task, we evaluated our system on Aimed and BioInfer PPI corpus; our system exceeded the state-of-art ensemble SVM system by 2.7% and 5.6% on f -scores.

Comparing the effects of kamikihito in Japan and kami-guibi-tang in Korea on memory enhancement: working towards the development of a global study.

PubMed

Watari, Hidetoshi; Shigyo, Michiko; Tanabe, Norio; Tohda, Michihisa; Cho, Ki-Ho; Kyung, Park Su; Jung, Woo Sang; Shimada, Yutaka; Shibahara, Naotoshi; Kuboyama, Tomoharu; Tohda, Chihiro

2015-03-01

Traditional medicine is widely used in East Asia, and studies that demonstrate its usefulness have recently become more common. However, formulation-based studies are not globally understood because these studies are country-specific. There are many types of formulations that have been introduced to Japan and Korea from China. Establishing whether a same-origin formulation has equivalent effects in other countries is important for the development of studies that span multiple countries. The present study compared the effects of same-origin traditional medicine used in Japan and Korea in an in vivo experiment. We prepared drugs that had the same origin and the same components. The drugs are called kamikihito (KKT) in Japan and kami-guibi-tang (KGT) in Korea. KKT (500 mg extract/kg/day) and KGT (500 mg extract/kg/day) were administered to ddY mice, and object recognition and location memory tests were performed. KKT and KGT administration yielded equivalent normal memory enhancement effects. 3D-HPLC showed similar, but not identical, patterns of the detected compounds between KKT and KGT. This comparative research approach enables future global clinical studies of traditional medicine to be conducted through the use of the formulations prescribed in each country. Copyright © 2014 John Wiley & Sons, Ltd.

Comparison of collagen matrix treatment impregnated with platelet rich plasma vs bone marrow.

PubMed

Minamimura, Ai; Ichioka, Shigeru; Sano, Hitomi; Sekiya, Naomi

2014-02-01

This study has reported the efficacy of an autologous bone marrow-impregnated collagen matrix experimentally and clinically. Then, it reflected that platelet rich plasma (PRP) was as good a source of growth factors as bone marrow and available in a less invasive procedure. This study aimed to compare the efficacy of a PRP-impregnated collagen matrix with that of a bone marrow-impregnated collagen matrix by quantifying wound size and capillary density using genetically diabetic db/db mice. Bone marrow cells were obtained from femurs of ddy mice. Then, a small amount of collagen matrix was immersed in bone marrow suspension. This is called a bone marrow-impregnated collagen matrix. PRP was obtained from healthy human blood and a small amount of collagen matrix was immersed in PRP. This is called a PRP-impregnated collagen matrix. A bone marrow-impregnated collagen matrix and PRP-impregnated collagen matrix were applied to excisional skin wounds on a genetically healing-impaired mouse (n = 6) and wounds were evaluated 6 days after the procedure. Wounds were divided into two groups: PRP (n = 6), in which a PRP-impregnated collagen matrix was applied; and bone marrow (n = 6), in which collagen immersed in a bone marrow suspension was applied. There was no significant difference between the PRP and bone-marrow groups in the rate of vascular density increase or wound size decrease. The present study suggested that the PRP-impregnated collagen matrix promotes repair processes at least as strongly as the bone marrow-impregnated collagen matrix. Given lower invasiveness, the PRP-impregnated collagen matrix would have advantages in clinical use.

Ibrutinib Dosing Strategies Based on Interaction Potential of CYP3A4 Perpetrators Using Physiologically Based Pharmacokinetic Modeling.

PubMed

de Zwart, L; Snoeys, J; De Jong, J; Sukbuntherng, J; Mannaert, E; Monshouwer, M

2016-11-01

Based on ibrutinib pharmacokinetics and potential sensitivity towards CYP3A4-mediated drug-drug interactions (DDIs), a physiologically based pharmacokinetic approach was developed to mechanistically describe DDI with various CYP3A4 perpetrators in healthy men under fasting conditions. These models were verified using clinical data for ketoconazole (strong CYP3A4 inhibitor) and used to prospectively predict and confirm the inducing effect of rifampin (strong CYP3A4 inducer); DDIs with mild (fluvoxamine, azithromycin) and moderate inhibitors (diltiazem, voriconazole, clarithromycin, itraconazole, erythromycin), and moderate (efavirenz) and strong CYP3A4 inducers (carbamazepine), were also predicted. Ketoconazole increased ibrutinib area under the curve (AUC) by 24-fold, while rifampin decreased ibrutinib AUC by 10-fold; coadministration of ibrutinib with strong inhibitors or inducers should be avoided. The ibrutinib dose should be reduced to 140 mg (quarter of maximal prescribed dose) when coadministered with moderate CYP3A4 inhibitors so that exposures remain within observed ranges at therapeutic doses. Thus, dose recommendations for CYP3A4 perpetrator use during ibrutinib treatment were developed and approved for labeling. © 2016 American Society for Clinical Pharmacology and Therapeutics.

Incendiary Devices for the in-situ Combustion of Crude Oil Slicks

DTIC Science & Technology

1983-01-01

contiennent. Celles-cl se composent principalement d’un oxydant , le perchlorate d’ammonium, d’un carburant, une poudre m~tallique, et d’un liant...20.8 I- R T: 78% vt. R-45HT/22% wt. DDI-1410. 2- Epoxy: 85% vt. Epon 815/15% wt. Hysol 3543. 3- Solvent: ethyl alcohol . 4- F-ND: boron-potassium nitrate

Reconstituting protein interaction networks using parameter-dependent domain-domain interactions

PubMed Central

2013-01-01

Background We can describe protein-protein interactions (PPIs) as sets of distinct domain-domain interactions (DDIs) that mediate the physical interactions between proteins. Experimental data confirm that DDIs are more consistent than their corresponding PPIs, lending support to the notion that analyses of DDIs may improve our understanding of PPIs and lead to further insights into cellular function, disease, and evolution. However, currently available experimental DDI data cover only a small fraction of all existing PPIs and, in the absence of structural data, determining which particular DDI mediates any given PPI is a challenge. Results We present two contributions to the field of domain interaction analysis. First, we introduce a novel computational strategy to merge domain annotation data from multiple databases. We show that when we merged yeast domain annotations from six annotation databases we increased the average number of domains per protein from 1.05 to 2.44, bringing it closer to the estimated average value of 3. Second, we introduce a novel computational method, parameter-dependent DDI selection (PADDS), which, given a set of PPIs, extracts a small set of domain pairs that can reconstruct the original set of protein interactions, while attempting to minimize false positives. Based on a set of PPIs from multiple organisms, our method extracted 27% more experimentally detected DDIs than existing computational approaches. Conclusions We have provided a method to merge domain annotation data from multiple sources, ensuring large and consistent domain annotation for any given organism. Moreover, we provided a method to extract a small set of DDIs from the underlying set of PPIs and we showed that, in contrast to existing approaches, our method was not biased towards DDIs with low or high occurrence counts. Finally, we used these two methods to highlight the influence of the underlying annotation density on the characteristics of extracted DDIs. Although increased annotations greatly expanded the possible DDIs, the lack of knowledge of the true biological false positive interactions still prevents an unambiguous assignment of domain interactions responsible for all protein network interactions. Executable files and examples are given at: http://www.bhsai.org/downloads/padds/ PMID:23651452

Factors which may limit the value of dietary diversity and its association with nutritional outcomes in preschool children in high burden districts of India.

PubMed

Nithya, Devanesan Jacinth; Bhavani, Ramanathapuram Vaidyanathan

2018-01-01

Dietary diversity plays a critical role in infants as they need energy and nutrient dense foods for both physical and mental development. This study examines whether three dietary diversity indices validate against Nutrient Adequacy Ratio (NAR) and Mean Adequacy Ratio (MAR) and studies the relationship of dietary diversity with nutritional status of preschool children, in two districts of India: Wardha district in Maharashtra state and Koraput district in Odisha state. Dietary diversity was calculated using: individual food scores calculated using 24 hour diet recall (FS24hr) data; household dietary diversity using Berry's index (DDI) and food scores calculated using food frequency data (FSFFQ). Nutritional status was assessed by anthropometric indices. It was observed that 42.7% of 1 to 5 years children were underweight, 38% stunted and 27.6% wasted across both locations. The dietary diversity was found to be relatively better in Wardha when compared with Koraput with mean diversity of FS24hr 7, DDI 90 and FSFFQ 63 in both locations. Preschool children in both locations consumed a cereal based diet. Apart from protein in both locations and energy in Koraput, the NAR of all nutrients consumed was <70% of requirement. MAR showed lower consumption of nutrients than the recommended levels (50% adequacy). NAR and MAR correlate with FS24hr indicating that dietary diversity calculated using 24 hour diet recall ensures nutrient adequacy but showed association only with Height-for-Age scores. Dietary diversity calculated using three methods did not show any correlation with nutritional status of 1 to 5 years children.

Repetitive nonreentrant ventriculoatrial synchrony: An underrecognized cause of pacemaker-related arrhythmia.

PubMed

Sharma, Parikshit S; Kaszala, Karoly; Tan, Alex Y; Koneru, Jayanthi N; Shepard, Richard; Ellenbogen, Kenneth A; Huizar, Jose F

2016-08-01

Similar to endless loop tachycardia (ELT), repetitive nonreentrant ventriculoatrial synchrony (RNRVAS) is a ventriculoatrial (VA) synchrony pacemaker-mediated arrhythmia. RNRVAS was first described in 1990 and can only occur in the presence of retrograde VA conduction and dual-chamber or cardiac resynchronization devices with tracking (P-synchronous ventricular pacing such as DDD, DDDR) or nontracking pacing modes that allow AV-sequential pacing (DDI, DDIR). RNRVAS is promoted by (1) high lower rate limit or any feature that allows rapid pacing, (2) long AV intervals, or (3) long postventricular atrial refractory period (PVARP). In contrast to ELT, RNRVAS is a less well-recognized form of pacemaker-mediated arrhythmia; thus, unlike ELT, there are no specific device algorithms to prevent, recognize, and terminate RNRVAS. However, RNRVAS has been recently shown to occur frequently. We present a series of cases, some of which were found fortuitously. Owing to its clinical implications, we propose that algorithms should be developed to prevent, identify, and terminate RNRVAS. Published by Elsevier Inc.

Development and validation of a survey instrument for assessing prescribers' perception of computerized drug-drug interaction alerts.

PubMed

Zheng, Kai; Fear, Kathleen; Chaffee, Bruce W; Zimmerman, Christopher R; Karls, Edward M; Gatwood, Justin D; Stevenson, James G; Pearlman, Mark D

2011-12-01

To develop a theoretically informed and empirically validated survey instrument for assessing prescribers' perception of computerized drug-drug interaction (DDI) alerts. The survey is grounded in the unified theory of acceptance and use of technology and an adapted accident causation model. Development of the instrument was also informed by a review of the extant literature on prescribers' attitude toward computerized medication safety alerts and common prescriber-provided reasons for overriding. To refine and validate the survey, we conducted a two-stage empirical validation study consisting of a pretest with a panel of domain experts followed by a field test among all eligible prescribers at our institution. The resulting survey instrument contains 28 questionnaire items assessing six theoretical dimensions: performance expectancy, effort expectancy, social influence, facilitating conditions, perceived fatigue, and perceived use behavior. Satisfactory results were obtained from the field validation; however, a few potential issues were also identified. We analyzed these issues accordingly and the results led to the final survey instrument as well as usage recommendations. High override rates of computerized medication safety alerts have been a prevalent problem. They are usually caused by, or manifested in, issues of poor end user acceptance. However, standardized research tools for assessing and understanding end users' perception are currently lacking, which inhibits knowledge accumulation and consequently forgoes improvement opportunities. The survey instrument presented in this paper may help fill this methodological gap. We developed and empirically validated a survey instrument that may be useful for future research on DDI alerts and other types of computerized medication safety alerts more generally.

A computer-aided differential diagnosis between UIP and NSIP using automated assessment of the extent and distribution of regional disease patterns at HRCT: comparison with the radiologist's decision

NASA Astrophysics Data System (ADS)

Kim, Namkug; Seo, Joon Beom; Park, Sang Ok; Lee, Youngjoo; Lee, Jeongjin

2009-02-01

To evaluate the accuracy of computer aided differential diagnosis (CADD) between usual interstitial pneumonia (UIP) and nonspecific interstitial pneumonia (NSIP) at HRCT in comparison with that of a radiologist's decision. A computerized classification for six local disease patterns (normal, NL; ground-glass opacity, GGO; reticular opacity, RO; honeycombing, HC; emphysema, EM; and consolidation, CON) using texture/shape analyses and a SVM classifier at HRCT was used for pixel-by-pixel labeling on the whole lung area. The mode filter was applied on the results to reduce noise. Area fraction (AF) of each pattern, directional probabilistic density function (pdf) (dPDF: mean, SD, skewness of pdf /3 directions: superior-inferior, anterior-posterior, central-peripheral), regional cluster distribution pattern (RCDP: number, mean, SD of clusters, mean, SD of centroid of clusters) were automatically evaluated. Spatially normalized left and right lungs were evaluated separately. Disease division index (DDI) on every combination of AFs and asymmetric index (AI) between left and right lung ((left-right)/left) were also evaluated. To assess the accuracy of the system, fifty-four HRCT data sets in patients with pathologically diagnosed UIP (n=26) and NSIP (n=28) were used. For a classification procedure, a CADD-SVM classifier with internal parameter optimization, and sequential forward floating feature selection (SFFS) were employed. The accuracy was assessed by a 5-folding cross validation with 20- times repetition. For comparison, two thoracic radiologists reviewed the whole HRCT images without clinical information and diagnose each case either as UIP or NSIP. The accuracies of radiologists' decision were 0.75 and 0.87, respectively. The accuracies of the CADD system using the features of AF, dPDF, AI of dPDF, RDP, AI of RDP, DDI were 0.70, 0.79, 0.77, 0.80, 0.78, 0.81, respectively. The accuracy of optimized CADD using all features after SFFS was 0.91. We developed the CADD system to differentiate between UIP and NSIP using automated assessment of the extent and distribution of regional disease patterns at HRCT.

VX-509 (Decernotinib)-Mediated CYP3A Time-Dependent Inhibition: An Aldehyde Oxidase Metabolite as a Perpetrator of Drug-Drug Interactions.

PubMed

Zetterberg, Craig; Maltais, Francois; Laitinen, Leena; Liao, Shengkai; Tsao, Hong; Chakilam, Ananthsrinivas; Hariparsad, Niresh

2016-08-01

(R)-2-((2-(1H-pyrrolo[2,3-b]pyridin-3-yl)pyrimidin-4-yl)amino)-2-methyl-N-(2,2,2-trifluoroethyl)butanamide (VX-509, decernotinib) is an oral Janus kinase 3 inhibitor that has been studied in patients with rheumatoid arthritis. Patients with rheumatoid arthritis often receive multiple medications, such as statins and steroids, to manage the signs and symptoms of comorbidities, which increases the chances of drug-drug interactions (DDIs). Mechanism-based inhibition is a subset of time-dependent inhibition (TDI) and occurs when a molecule forms a reactive metabolite which irreversibly binds and inactivates drug-metabolizing enzymes, potentially increasing the systemic load to toxic concentrations. Traditionally, perpetrating compounds are screened using human liver microsomes (HLMs); however, this system may be inadequate when the precipitant is activated by a non-cytochrome P450 (P450)-mediated pathway. Even though studies assessing competitive inhibition and TDI using HLM suggested a low risk for CYP3A4-mediated DDI in the clinic, VX-509 increased the area under the curve of midazolam, atorvastatin, and methyl-prednisolone by approximately 12.0-, 2.7-, and 4.3-fold, respectively. Metabolite identification studies using human liver cytosol indicated that VX-509 is converted to an oxidative metabolite, which is the perpetrator of the DDIs observed in the clinic. As opposed to HLM, hepatocytes contain the full complement of drug-metabolizing enzymes and transporters and can be used to assess TDI arising from non-P450-mediated metabolic pathways. In the current study, we highlight the role of aldehyde oxidase in the formation of the hydroxyl-metabolite of VX-509, which is involved in clinically significant TDI-based DDIs and represents an additional example in which a system-dependent prediction of TDI would be evident. Copyright © 2016 by The American Society for Pharmacology and Experimental Therapeutics.

Microdosing and Other Phase 0 Clinical Trials: Facilitating Translation in Drug Development.

PubMed

Burt, T; Yoshida, K; Lappin, G; Vuong, L; John, C; de Wildt, S N; Sugiyama, Y; Rowland, M

2016-04-01

A number of drivers and developments suggest that microdosing and other phase 0 applications will experience increased utilization in the near-to-medium future. Increasing costs of drug development and ethical concerns about the risks of exposing humans and animals to novel chemical entities are important drivers in favor of these approaches, and can be expected only to increase in their relevance. An increasing body of research supports the validity of extrapolation from the limited drug exposure of phase 0 approaches to the full, therapeutic exposure, with modeling and simulations capable of extrapolating even non-linear scenarios. An increasing number of applications and design options demonstrate the versatility and flexibility these approaches offer to drug developers including the study of PK, bioavailability, DDI, and mechanistic PD effects. PET microdosing allows study of target localization, PK and receptor binding and occupancy, while Intra-Target Microdosing (ITM) allows study of local therapeutic-level acute PD coupled with systemic microdose-level exposure. Applications in vulnerable populations and extreme environments are attractive due to the unique risks of pharmacotherapy and increasing unmet healthcare needs. All phase 0 approaches depend on the validity of extrapolation from the limited-exposure scenario to the full exposure of therapeutic intent, but in the final analysis the potential for controlled human data to reduce uncertainty about drug properties is bound to be a valuable addition to the drug development process.

The Effect of Nizatidine, a MATE2K Selective Inhibitor, on the Pharmacokinetics and Pharmacodynamics of Metformin in Healthy Volunteers

PubMed Central

Morrissey, Kari M.; Stocker, Sophie L.; Chen, Eugene C.; Castro, Richard A.; Brett, Claire M.; Giacomini, Kathleen M.

2015-01-01

Background and Objectives In the proximal tubule, basic drugs are transported from the renal cells to the tubule lumen through the concerted action of the H+/organic cation antiporters, multidrug and toxin extrusion 1 (MATE1) and 2K (MATE2K). Dual inhibitors of the MATE transporters have been shown to have a clinically relevant effect on the pharmacokinetics of concomitantly administered basic drugs. However, the clinical impact of selective renal organic cation transport inhibition on the pharmacokinetics and pharmacodynamics of basic drugs, such as metformin, is unknown. This study sought to identify a selective MATE2K inhibitor in vitro and to determine its clinical impact on the pharmacokinetics and pharmacodynamics of metformin in healthy subjects. Methods A strategic cell-based screen of 71 U.S. Food and Drug Administration (FDA)-approved medications was conducted to identify selective inhibitors of renal organic cation transporters that are capable of inhibiting at clinically relevant concentrations. From this screen, nizatidine was identified and predicted to be a clinically potent and selective inhibitor of MATE2K-mediated transport. The effect of nizatidine on the pharmacokinetics and pharmacodynamics of metformin was evaluated in 12 healthy volunteers in an open-label, randomized, two-phase crossover drug-drug interaction (DDI) study. Results In healthy volunteers, the MATE2K-selective inhibitor, nizatidine, significantly increased the apparent volume of distribution, half-life and hypoglycemic activity of metformin. However, despite achieving unbound maximum concentrations greater than the in vitro inhibition potency (IC50) of MATE2K-mediated transport, nizatidine did not affect the renal clearance or net secretory clearance of metformin. Conclusion This study demonstrates that a selective inhibition of MATE2K by nizatidine, affected the apparent volume of distribution, tissue levels and peripheral effects of metformin. However, nizatidine did not alter systemic concentrations or the renal clearance of metformin, suggesting that specific MATE2K inhibition may not be sufficient to cause renal DDIs with basic drugs. PMID:26507723

Adverse drug reactions due to drug-drug interactions with proton pump inhibitors: assessment of systematic reviews with AMSTAR method.

PubMed

Yucel, Emre; Sancar, Mesut; Yucel, Aylin; Okuyan, Betul

2016-01-01

Many systematic reviews resulted in claims on drug-drug interactions (DDIs) with proton pump inhibitors (PPIs). Such a large number begs for consensus on the clinical significance of findings. We critically evaluated the safety of PPI use with respect to DDIs with a meta-review of systematic reviews published between 1978 and 2015. We assessed the evidence by their reliability, repeatability, transparency, and objectivity according to the Assessment of Multiple Systematic Reviews (AMSTAR) criteria. Clinicians must assess risks for each PPI for certain comorbid conditions. DDIs don't substantiate class effect for PPIs; each PPI could induce unique DDIs. Concomitant use of PPIs with thienopyridines (e.g. clopidogrel) could be justified in patients without strong affinity to cytochrome CYP2C19 and with high risk of bleeding (e.g. patients with prior upper gastrointestinal bleeding, Helicobacter pylori infection, advanced age, steroid treatment, and nonsteroidal anti-inflammatory drug use). DDIs could occur in an AIDS subpopulation treated with highly active antiretroviral therapy (HAART). DDIs exist for cancer patients undergoing targeted therapy. Hypomagnesemia could increase in the setting of advanced age and polypharmacy. Omeprazole poses high risks owing to its pharmacokinetic DDI profile. Future systematic reviews should incorporate these additional risks for better clinical guidance.

An Analysis of Enzyme Kinetics Data for Mitochondrial DNA Strand Termination by Nucleoside Reverse Transcription Inhibitors

PubMed Central

Wendelsdorf, Katherine V.; Song, Zhuo; Cao, Yang; Samuels, David C.

2009-01-01

Nucleoside analogs used in antiretroviral treatment have been associated with mitochondrial toxicity. The polymerase-γ hypothesis states that this toxicity stems from the analogs' inhibition of the mitochondrial DNA polymerase (polymerase-γ) leading to mitochondrial DNA (mtDNA) depletion. We have constructed a computational model of the interaction of polymerase-γ with activated nucleoside and nucleotide analog drugs, based on experimentally measured reaction rates and base excision rates, together with the mtDNA genome size, the human mtDNA sequence, and mitochondrial dNTP concentrations. The model predicts an approximately 1000-fold difference in the activated drug concentration required for a 50% probability of mtDNA strand termination between the activated di-deoxy analogs d4T, ddC, and ddI (activated to ddA) and the activated forms of the analogs 3TC, TDF, AZT, FTC, and ABC. These predictions are supported by experimental and clinical data showing significantly greater mtDNA depletion in cell culture and patient samples caused by the di-deoxy analog drugs. For zidovudine (AZT) we calculated a very low mtDNA replication termination probability, in contrast to its reported mitochondrial toxicity in vitro and clinically. Therefore AZT mitochondrial toxicity is likely due to a mechanism that does not involve strand termination of mtDNA replication. PMID:19132079

Quantification of damage due to low-dose radiation exposure in mice: construction and application of a biodosimetric model using mRNA indicators in circulating white blood cells

PubMed Central

Ishihara, Hiroshi; Tanaka, Izumi; Yakumaru, Haruko; Tanaka, Mika; Yokochi, Kazuko; Fukutsu, Kumiko; Tajima, Katsushi; Nishimura, Mayumi; Shimada, Yoshiya; Akashi, Makoto

2016-01-01

Biodosimetry, the measurement of radiation damage in a biologic sample, is a reliable tool for increasing the accuracy of dose estimation. Although established chromosome analyses are suitable for estimating the absorbed dose after high-dose irradiation, biodosimetric methodology to measure damage following low-dose exposure is underdeveloped. RNA analysis of circulating blood containing radiation-sensitive cells is a candidate biodosimetry method. Here we quantified RNA from a small amount of blood isolated from mice following low-dose body irradiation (<0.5 Gy) aimed at developing biodosimetric tools for situations that are difficult to study in humans. By focusing on radiation-sensitive undifferentiated cells in the blood based on Myc RNA expression, we quantified the relative levels of RNA for DNA damage-induced (DDI) genes, such as Bax, Bbc3 and Cdkn1a. The RNA ratios of DDI genes/Myc in the blood increased in a dose-dependent manner 4 h after whole-body irradiation at doses ranging from 0.1 to 0.5 Gy (air-kerma) of X-rays, regardless of whether the mice were in an active or resting state. The RNA ratios were significantly increased after 0.014 Gy (air-kerma) of single X-ray irradiation. The RNA ratios were directly proportional to the absorbed doses in water ranging from 0.1 to 0.5 Gy, based on gamma-irradiation from 137Cs. Four hours after continuous irradiation with gamma-rays or by internal contamination with a beta-emitter, the increased RNA ratios resembled those following single irradiation. These findings indicate that the RNA status can be utilized as a biodosimetric tool to estimate low-dose radiation when focusing on undifferentiated cells in blood. PMID:26589759

Long-term exposure of mice to nucleoside analogues disrupts mitochondrial DNA maintenance in cortical neurons.

PubMed

Zhang, Yulin; Song, Fengli; Gao, Ziyun; Ding, Wei; Qiao, Luxin; Yang, Sufang; Chen, Xi; Jin, Ronghua; Chen, Dexi

2014-01-01

Nucleoside analogue reverse transcriptase inhibitor (NRTI), an integral component of highly active antiretroviral therapy (HAART), was widely used to inhibit HIV replication. Long-term exposure to NRTIs can result in mitochondrial toxicity which manifests as lipoatrophy, lactic acidosis, cardiomyopathy and myopathy, as well as polyneuropathy. But the cerebral neurotoxicity of NRTIs is still not well known partly due to the restriction of blood-brain barrier (BBB) and the complex microenvironment of the central nervous system (CNS). In this study, the Balb/c mice were administered 50 mg/kg stavudine (D4T), 100 mg/kg zidovudine (AZT), 50 mg/kg lamivudine (3TC) or 50 mg/kg didanosine (DDI) per day by intraperitoneal injection, five days per week for one or four months, and primary cortical neurons were cultured and exposed to 25 µM D4T, 50 µM AZT, 25 µM 3TC or 25 µM DDI for seven days. Then, single neuron was captured from mouse cerebral cortical tissues by laser capture microdissection. Mitochondrial DNA (mtDNA) levels of the primary cultured cortical neurons, and captured neurons or glial cells, and the tissues of brains and livers and muscles were analyzed by relative quantitative real-time PCR. The data showed that mtDNA did not lose in both NRTIs exposed cultured neurons and one month NRTIs treated mouse brains. In four months NRTIs treated mice, brain mtDNA levels remained unchanged even if the mtDNA levels of liver (except for 3TC) and muscle significantly decreased. However, mtDNA deletion was significantly higher in the captured neurons from mtDNA unchanged brains. These results suggest that long-term exposure to NRTIs can result in mtDNA deletion in mouse cortical neurons.

A molecular computational model improves the preoperative diagnosis of thyroid nodules

PubMed Central

2012-01-01

Background Thyroid nodules with indeterminate cytological features on fine needle aspiration (FNA) cytology have a 20% risk of thyroid cancer. The aim of the current study was to determine the diagnostic utility of an 8-gene assay to distinguish benign from malignant thyroid neoplasm. Methods The mRNA expression level of 9 genes (KIT, SYNGR2, C21orf4, Hs.296031, DDI2, CDH1, LSM7, TC1, NATH) was analysed by quantitative PCR (q-PCR) in 93 FNA cytological samples. To evaluate the diagnostic utility of all the genes analysed, we assessed the area under the curve (AUC) for each gene individually and in combination. BRAF exon 15 status was determined by pyrosequencing. An 8-gene computational model (Neural Network Bayesian Classifier) was built and a multiple-variable analysis was then performed to assess the correlation between the markers. Results The AUC for each significant marker ranged between 0.625 and 0.900, thus all the significant markers, alone and in combination, can be used to distinguish between malignant and benign FNA samples. The classifier made up of KIT, CDH1, LSM7, C21orf4, DDI2, TC1, Hs.296031 and BRAF had a predictive power of 88.8%. It proved to be useful for risk stratification of the most critical cytological group of the indeterminate lesions for which there is the greatest need of accurate diagnostic markers. Conclusion The genetic classification obtained with this model is highly accurate at differentiating malignant from benign thyroid lesions and might be a useful adjunct in the preoperative management of patients with thyroid nodules. PMID:22958914

Effects of mesh-related complications in vaginal surgery on quality of life.

PubMed

Kowalik, Claudia R; Lakeman, Mariëlle M E; de Kraker, Alyde T; Roovers, Jan Paul W R

2018-06-16

Vaginal mesh surgery is subject of debate due to the impact of mesh-related complications on patient's lives. Not all of these complications are symptomatic. Restoration of the anatomy and improvement of pelvic floor function as a result may counter the experienced discomfort related to adverse events. We hypothesized that health-related quality of life (HR-QoL) is comparable in women after vaginal mesh surgery regardless of the presence or absence of a mesh-specific complication. This was a cross-sectional study of 128 women who had vaginal mesh surgery in a Dutch university hospital between 2007 and 2012. HR-QoL was measured in women with and without mesh complications using standardized QoL questionnaires Urogenital Distress Inventory-6 (UDI-6), Incontinence Impact Questionnaire (IIQ), Defecation Distress Inventory (DDI), and Pelvic Organ Prolapse/Urinary Incontinence Sexual Function Questionnaire (PISQ-12). Complications were scored according to the International Urogynecological Association (IUGA) complication classification. Comparisons between groups were performed with Student's t test and analysis of variance (ANOVA) test. In 29 (23%) women, a mesh-related complication occurred. The domain scores of the UDI-6, DDI, IIQ, and PISQ showed no statistically significant differences between women with and without a mesh-related complication. A post hoc analysis showed similar HR-QoL for those in whom the complication had been resolved and those with persistent symptoms of the complication. Mesh surgery imposes specific complications. When counseling patients about the potential adverse events related to vaginal mesh surgery, it is important to inform them that mesh-related complications do not negatively affect QoL related to micturition, defecation, and sexual functioning.

Evaluation of the potential interaction between tofacitinib and drugs that undergo renal tubular secretion using metformin, an in vivo marker of renal organic cation transporter 2.

PubMed

Klamerus, Karen J; Alvey, Christine; Li, Lei; Feng, Bo; Wang, Rong; Kaplan, Irina; Shi, Haihong; Dowty, Martin E; Krishnaswami, Sriram

2014-11-01

Tofacitinib is a novel, oral Janus kinase inhibitor. The potential for drug-drug interactions (DDIs) between tofacitinib and drugs that undergo renal tubular secretion was evaluated using metformin as a probe transporter substrate, and genotyping for organic cation transporter (OCT) 1, OCT2 and multidrug and toxin extrusion 1 polymorphisms. Twenty-four healthy male subjects completed this open-label, fixed-sequence study. Subjects were administered a single oral metformin 500 mg dose on Days 1 and 4, and multiple oral tofacitinib 30 mg twice daily doses on Days 2, 3, and 4. Subjects underwent serial blood and urine samplings (Days 1 and 4) to estimate metformin pharmacokinetics. A single blood sample for tofacitinib was collected 2 hours after the morning dose (Day 4). The 90% confidence intervals for the ratios of maximum plasma concentration, area under the curve and renal clearance of metformin, with and without tofacitinib, were contained within the 80-125% acceptance range commonly used to establish a lack of DDI. No deaths, serious adverse events (AEs), severe AEs or discontinuations due to AEs were reported. The study confirms tofacitinib is unlikely to impact the pharmacokinetics of drugs that undergo renal tubular secretion, and concurs with its weak in vitro OCT2 inhibitory profile. © 2014, The American College of Clinical Pharmacology.

Navy Civilian (Civil Service) Billet Costs--FY 1981.

DTIC Science & Technology

1981-07-01

REPAIRItEN-- WACE LFADER (WE) (UNDISCOUNTED) INITIAL ANNUALLY YEARS IN LIFE CYCLE BILLET RECURRING GRD COST COST 1 5 10 15 20 5 318 32611 31013 128594 207215...and supporting each billet were established and are presented in 1-, 5-, 10-, 15-, and 20- year increments. DDI j ANඑ 1473 EDITION OF I OV...PAGSVfa Des ENotom.) FOREWORD This effort was conducted in support of Navy Decision Coordinating Paper ZI 170-PN, subproject Z1170-PN.05 (Reducing

Exploring convolutional neural networks for drug–drug interaction extraction

PubMed Central

Segura-Bedmar, Isabel; Martínez, Paloma

2017-01-01

Abstract Drug–drug interaction (DDI), which is a specific type of adverse drug reaction, occurs when a drug influences the level or activity of another drug. Natural language processing techniques can provide health-care professionals with a novel way of reducing the time spent reviewing the literature for potential DDIs. The current state-of-the-art for the extraction of DDIs is based on feature-engineering algorithms (such as support vector machines), which usually require considerable time and effort. One possible alternative to these approaches includes deep learning. This technique aims to automatically learn the best feature representation from the input data for a given task. The purpose of this paper is to examine whether a convolutional neural network (CNN), which only uses word embeddings as input features, can be applied successfully to classify DDIs from biomedical texts. Proposed herein, is a CNN architecture with only one hidden layer, thus making the model more computationally efficient, and we perform detailed experiments in order to determine the best settings of the model. The goal is to determine the best parameter of this basic CNN that should be considered for future research. The experimental results show that the proposed approach is promising because it attained the second position in the 2013 rankings of the DDI extraction challenge. However, it obtained worse results than previous works using neural networks with more complex architectures. PMID:28605776

A Case of a Cardiac Resynchronization Therapy-Defibrillator Exhibiting a Lower and Alternately Variable Basic Rate.

PubMed

Iwazaki, Keigo; Kojima, Toshiya; Murasawa, Takahide; Yokota, Jun; Tanimoto, Hikaru; Matsuda, Jun; Fukuma, Nobuaki; Matsubara, Takumi; Shimizu, Yu; Oguri, Gaku; Hasumi, Eriko; Kubo, Hitoshi; Chang, Kyungho; Fujiu, Katsuhito; Komuro, Issei

2018-05-30

A cardiac resynchronization therapy defibrillator (CRT-D) (Medtronic Inc. Protecta XT) was implanted in a 67-year-old man who had cardiac sarcoidosis with extremely low cardiac function. He had ventricular tachycardia which was controlled by catheter ablation, medication and pacing. The programmed mode was DDI, lower rate was 90 beats/minute, paced AV delay was 150 ms, and the noncompetitive atrial pacing (NCAP) function was programmed as 300 ms.After his admission for pneumonia and heart failure, we changed his DDI mode to a DDD mode because he had atrial tachycardia, which led to inadequate bi-ventricular pacing. After a while, there were cycle lengths which were longer than his device setting and alternately varied. We were able to avoid this phenomenon with AV delay of 120 ms and NCAP of 200 ms.NCAP is an algorithm which creates a gap above a certain period after the detection of an atrial signal during the postventricular atrial refractory period of the pacemaker. This is to prevent atrial tachycardia and repetitive non-reentrant ventriculoatrial (VA) synchrony in the presence of retrograde VA conduction. But in this case, NCAP algorithm induced much lower rate than the programmed basic lower rate. This situation produced some arrhythmias and exacerbated symptoms of heart failure. This had to be paid attention to, especially when the device was programmed at high basic heart rate.

Pharmacokinetic interactions among imatinib, bosentan and sildenafil, and their clinical implications in severe pulmonary arterial hypertension

PubMed Central

Renard, Didier; Bouillon, Thomas; Zhou, Ping; Flesch, Gerard; Quinn, Debbie

2015-01-01

Aims This study characterized the population pharmacokinetics (PK) of imatinib in patients with severe pulmonary arterial hypertension (PAH), investigated drug–drug interactions (DDI) among imatinib, sildenafil and bosentan, and evaluated their clinical implications. Methods Plasma concentrations of imatinib, bosentan and sildenafil were collected in a phase III study and were used to characterize the PK of imatinib in this population. DDIs among the three drugs were quantified using a linear mixed model and log-transformed drug concentrations. Results The population mean estimates of apparent clearance (CL/F) and volume (V/F) were 10.8 l h–1 (95% CI 9.2, 12.4 l h–1) and 267 l (95% CI 208, 326 l), respectively. It was estimated that sildenafil concentrations increased, on average, by 64% (95% CI 32%, 103%) and bosentan concentrations by 51% (95% CI 12%, 104%), in the presence of imatinib. Despite increased concentrations of co-medications, treatment differences between imatinib and placebo for change in 6 min walk distance and pulmonary vascular resistance were relatively constant across the entire concentration range for sildenafil and bosentan. Overall, higher concentrations of imatinib and bosentan were not associated with increasing liver enzymes (serum glutamic oxaloacetic transaminases [SGOT]/serum glutamic-pyruvic transaminase [SGPT]). Conclusions Population PKs of imatinib in patients with severe PAH were found comparable with those of patients with chronic myeloid leukemia. Imatinib was found effective regardless of the co-medications and showed intrinsic efficacy beyond merely elevating the concentrations of the co-medications due to DDIs. There was no evidence of increased risk of liver toxicity upon co-administration with bosentan. PMID:25581063

Drug-drug interactions and adverse drug reactions in polypharmacy among older adults: an integrative review.

PubMed

Rodrigues, Maria Cristina Soares; Oliveira, Cesar de

2016-09-01

to identify and summarize studies examining both drug-drug interactions (DDI) and adverse drug reactions (ADR) in older adults polymedicated. an integrative review of studies published from January 2008 to December 2013, according to inclusion and exclusion criteria, in MEDLINE and EMBASE electronic databases were performed. forty-seven full-text studies including 14,624,492 older adults (≥ 60 years) were analyzed: 24 (51.1%) concerning ADR, 14 (29.8%) DDI, and 9 studies (19.1%) investigating both DDI and ADR. We found a variety of methodological designs. The reviewed studies reinforced that polypharmacy is a multifactorial process, and predictors and inappropriate prescribing are associated with negative health outcomes, as increasing the frequency and types of ADRs and DDIs involving different drug classes, moreover, some studies show the most successful interventions to optimize prescribing. DDI and ADR among older adults continue to be a significant issue in the worldwide. The findings from the studies included in this integrative review, added to the previous reviews, can contribute to the improvement of advanced practices in geriatric nursing, to promote the safety of older patients in polypharmacy. However, more research is needed to elucidate gaps. identificar e sintetizar estudos que examinam as interações medicamentosas (IM) e reações adversas a medicamentos (RAM) em idosos polimedicados. revisão integrativa de estudos publicados de janeiro de 2008 a dezembro de 2013, de acordo com critérios de inclusão e exclusão, nas bases de dados eletrônicas MEDLINE e EMBASE. foram analisados 47 estudos de texto completo, incluindo 14,624,492 idosos (≥ 60 anos): 24 (51,1%) sobre RAM, 14 (29,8%) sobre IM e 9 estudos (19,1%) que investigaram tanto IM como RAM. Encontramos uma variedade de desenhos metodológicos. Os estudos revisados reforçaram que a polifarmácia é um processo multifatorial, e os preditores e a prescrição inadequada estão associados a resultados negativos de saúde, como aumento da frequência e tipos de RAM e IM envolvendo diferentes classes de drogas, além disso, alguns estudos mostram as intervenções mais bem-sucedidas para otimizar a prescrição. IM e RAM entre idosos continuam a ser um problema significativo no mundo todo. Os resultados dos estudos incluídos nesta revisão integrativa, adicionado às revisões anteriores, podem contribuir para a melhoria das práticas avançadas de enfermagem geriátrica, para promover a segurança dos pacientes idosos em polifarmácia. No entanto, são necessárias mais pesquisas para elucidar lacunas. identificar y resumir los estudios que analizan tanto las interacciones medicamentosas (IM) como las reacciones adversas a medicamentos (RAM) en los adultos mayores polimedicados. revisión integradora de estudios publicados entre enero de 2008 a diciembre de 2013, siguiendo criterios de inclusión y exclusión, en las bases de datos electrónicas MEDLINE y EMBASE. cuarenta y siete estudios de texto completo incluidos fueron analizados incluyendo 14,624,492 adultos mayores (≥ 60 años), de ellos 24 (51,1%) en relación con RAM, 14 (29,9%) con IM y 9 estudios (19,1%) que investigaron tanto IM como RAM. Encontramos una gran variedad de diseños metodológicos. Los estudios revisados reforzaron el concepto que la polifarmacia es un proceso multifactorial, y los predictores y la prescripción inadecuada se asocian con resultados negativos para la salud tales como el aumento de la frecuencia y tipos de RAM y IM implicando diferentes clases de fármacos, además que algunos estudios muestran cuales son las intervenciones más exitosas para optimizar la prescripción. IM y RAM siguen siendo un problema importante en el mundo entero entre los adultos mayores. Los resultados de los estudios incluidos en esta revisión integradora, sumado a las revisiones previas, pueden contribuir a la mejora de las prácticas avanzadas de enfermería geriátrica, para promover la seguridad de los pacientes de mayor edad en la polifarmacia. Sin embargo, se necesita más investigación para esclarecer los vacíos de conocimiento.

Microdosing and Other Phase 0 Clinical Trials: Facilitating Translation in Drug Development

DOE PAGES

Burt, T.; Yoshida, K.; Lappin, G.; ...

2016-02-26

A number of drivers and developments suggest that microdosing and other phase 0 applications will experience increased utilization in the near-to-medium future. Increasing costs of drug development and ethical concerns about the risks of exposing humans and animals to novel chemical entities are important drivers in favor of these approaches, and can be expected only to increase in their relevance. An increasing body of research supports the validity of extrapolation from the limited drug exposure of phase 0 approaches to the full, therapeutic exposure, with modeling and simulations capable of extrapolating even non-linear scenarios. An increasing number of applications andmore » design options demonstrate the versatility and flexibility these approaches offer to drug developers including the study of PK, bioavailability, DDI, and mechanistic PD effects. PET microdosing allows study of target localization, PK and receptor binding and occupancy, while Intra-Target Microdosing (ITM) allows study of local therapeutic-level acute PD coupled with systemic microdose-level exposure. Applications in vulnerable populations and extreme environments are attractive due to the unique risks of pharmacotherapy and increasing unmet healthcare needs. Lastly, all phase 0 approaches depend on the validity of extrapolation from the limited-exposure scenario to the full exposure of therapeutic intent, but in the final analysis the potential for controlled human data to reduce uncertainty about drug properties is bound to be a valuable addition to the drug development process.« less

Microdosing and Other Phase 0 Clinical Trials: Facilitating Translation in Drug Development

DOE Office of Scientific and Technical Information (OSTI.GOV)

Burt, T.; Yoshida, K.; Lappin, G.

A number of drivers and developments suggest that microdosing and other phase 0 applications will experience increased utilization in the near-to-medium future. Increasing costs of drug development and ethical concerns about the risks of exposing humans and animals to novel chemical entities are important drivers in favor of these approaches, and can be expected only to increase in their relevance. An increasing body of research supports the validity of extrapolation from the limited drug exposure of phase 0 approaches to the full, therapeutic exposure, with modeling and simulations capable of extrapolating even non-linear scenarios. An increasing number of applications andmore » design options demonstrate the versatility and flexibility these approaches offer to drug developers including the study of PK, bioavailability, DDI, and mechanistic PD effects. PET microdosing allows study of target localization, PK and receptor binding and occupancy, while Intra-Target Microdosing (ITM) allows study of local therapeutic-level acute PD coupled with systemic microdose-level exposure. Applications in vulnerable populations and extreme environments are attractive due to the unique risks of pharmacotherapy and increasing unmet healthcare needs. Lastly, all phase 0 approaches depend on the validity of extrapolation from the limited-exposure scenario to the full exposure of therapeutic intent, but in the final analysis the potential for controlled human data to reduce uncertainty about drug properties is bound to be a valuable addition to the drug development process.« less

The relationship of thoracic kyphosis to gait performance and quality of life in women with osteoporosis.

PubMed

Sangtarash, F; Manshadi, F D; Sadeghi, A

2015-08-01

Thoracic kyphosis angle (TKA) increases with osteoporosis. This study aimed to investigate the relationship between magnitude of TKA and quality of life and gait performance in 34 osteoporotic women. Our results suggest that increasing TKA is significantly associated with decreasing quality of life (r = -0.48, p < 0.005) and gait performance (r = -0.74, p < 0.0005). Osteoporosis and its related effects are threatening health and quality of life especially in postmenopausal women. Increased thoracic kyphosis angle (TKA), as one of the most common adverse musculoskeletal changes, could be regarded as a quantitative index for osteoporotic patients' assessment. Dual digital inclinometer (DDI) is one of the latest tools for non-invasive TKA measurement. The main purpose of this study was to determine whether a relationship existed between the magnitude of TKA, gait performance, and quality of life in a group of osteoporotic women. Thirty-four osteoporotic women, aged 50-68, participated in this descriptive analytic study. The magnitude of TKA measured by using DDI and expressed as the kyphosis index (KI). Quality of life and gait performance were assessed using short form 36 (SF36) questionnaire and functional gait assessment test, respectively. Back extension range of motion (ROM) and back extensor strength were also assessed. Pearson's correlation test was used to analyze the data, with the significance level of p < 0.05. The findings revealed a statistically significant negative correlation between KI and quality of life (r = -0.48, p < 0.005) and KI and gait performance (r = -0.74, p < 0.0005). There was also a significantly negative relation between KI and back extension ROM and back extensor strength (p < 0.05). The results of this study demonstrated that increased thoracic kyphosis negatively affects gait performance and quality of life. This finding could be regarded as an important implication for therapist to pay more attention to the magnitude of thoracic kyphosis angle and its changes, when selecting appropriate therapeutic methods to improve gait performance and quality of life in osteoporosis women.

Two-dimensional solitons in dipolar Bose-Einstein condensates with spin-orbit coupling

NASA Astrophysics Data System (ADS)

Jiang, Xunda; Fan, Zhiwei; Chen, Zhaopin; Pang, Wei; Li, Yongyao; Malomed, Boris A.

2016-02-01

We report families of two-dimensional (2D) composite solitons in spinor dipolar Bose-Einstein condensates, with two localized components linearly mixed by the spin-orbit coupling (SOC), and the intrinsic nonlinearity represented by the dipole-dipole interaction (DDI) between atomic magnetic moments polarized in plane by an external magnetic field. Recently, stable solitons were predicted in the form of semivortices (composites built of coupled fundamental and vortical components) in the 2D system combining the SOC and contact attractive interactions. Replacing the latter by the anisotropic long-range DDI, we demonstrate that, for a fixed norm of the soliton, the system supports a continuous family of stable spatially asymmetric vortex solitons (AVSs), parameterized by an offset of the pivot of the vortical component relative to its fundamental counterpart. The offset is limited by a certain maximum value, while the energy of the AVS practically does not depend on the offset. At small values of the norm, the vortex solitons are subject to a weak oscillatory instability. In the present system, with the Galilean invariance broken by the SOC, the composite solitons are set in motion by a kick the strength of which exceeds a certain depinning value. The kicked solitons feature a negative effective mass, drifting along a spiral trajectory opposite to the direction of the kick. A critical angular velocity, up to which the semivortices may follow rotation of the polarizing magnetic field, is found too.

Development of a chemotherapy regimen interaction database for the mobile internet: detecting interactions with psychotropics through OncoRx-MI.

PubMed

Yap, Kevin Yi-Lwern; Chui, Wai Keung; Chan, Alexandre

2011-09-01

Cancer patients are at high risks of drug-drug interactions (DDIs). Clinicians need to know the magnitude of DDIs so as to better manage their patients' drug therapies. We have previously created a novel interaction database for oncology prescriptions (OncoRx). In this project, we leverage on 3G networks to further develop this database into an iPhone-specific application for the mobile internet (OncoRx-MI). Data on anticancer drugs (ACDs), chemotherapy regimens (CRegs) and DDIs with psychotropics were compiled from various hardcopy and online resources, and published articles from PubMed, Scopus and Science Direct. The database and iPhone web documents were designed using Adobe Dreamweaver CS4 and associated with a combination of open-source programming scripts. OncoRx-MI currently detects over 5000 DDIs (69.3% pharmacokinetic, 30.7% pharmacodynamic) between 256 single-agent and combination CRegs with 51 psychotropic drugs. OncoRx-MI fits the iPhone screen configuration, and displays information regarding the regimen, pharmacokinetics of the drugs and detected DDIs in tabular format for improved usability. OncoRx-MI is the first mobile DDI application of its kind which detects interactions for combination CRegs. Future versions will include DDIs with other drug categories. Usability studies on its impact in clinical practice will also be carried out.

Acetaminophen analog N-acetyl-m-aminophenol, but not its reactive metabolite, N-acetyl-p-benzoquinone imine induces CYP3A activity via inhibition of protein degradation.

PubMed

Santoh, Masataka; Sanoh, Seigo; Ohtsuki, Yuya; Ejiri, Yoko; Kotake, Yaichiro; Ohta, Shigeru

2017-05-06

Cytochrome P450 (CYP) 3A subfamily members are known to metabolize various types of drugs, highlighting the importance of understanding drug-drug interactions (DDI) depending on CYP3A induction or inhibition. While transcriptional regulation of CYP3A members is widely understood, post-translational regulation needs to be elucidated. We previously reported that acetaminophen (APAP) induces CYP3A activity via inhibition of protein degradation and proposed a novel DDI concept. N-Acetyl-p-benzoquinone imine (NAPQI), the reactive metabolite of APAP formed by CYP, is known to cause adverse events related to depletion of intracellular reduced glutathione (GSH). We aimed to inspect whether NAPQI rather than APAP itself could cause the inhibitory effects on protein degradation. We found that N-acetyl-l-cysteine, the precursor of GSH, and 1-aminobenzotriazole, a nonselective CYP inhibitor, had no effect on CYP3A1/23 protein levels affected by APAP. Thus, we used APAP analogs to test CYP3A1/23 mRNA levels, protein levels, and CYP3A activity. We found N-acetyl-m-aminophenol (AMAP), a regioisomer of APAP, has the same inhibitory effects of CYP3A1/23 protein degradation, while p-acetamidobenzoic acid (PAcBA), a carboxy-substituted form of APAP, shows no inhibitory effects. AMAP and PAcBA cannot be oxidized to quinone imine forms such as NAPQI, so the inhibitory effects could depend on the specific chemical structure of APAP. Copyright © 2017 Elsevier Inc. All rights reserved.

Determining Inappropriate Medication Alerts from "Inaccurate Warning" Overrides in the Intensive Care Unit.

PubMed

Rehr, Christine A; Wong, Adrian; Seger, Diane L; Bates, David W

2018-04-01

 This article aims to understand provider behavior around the use of the override reason "Inaccurate warning," specifically whether it is an effective way of identifying unhelpful medication alerts.  We analyzed alert overrides that occurred in the intensive care units (ICUs) of a major academic medical center between June and November 2016, focused on the following high-significance alert types: dose, drug-allergy alerts, and drug-drug interactions (DDI). Override appropriateness was analyzed by two independent reviewers using predetermined criteria.  A total of 268 of 26,501 ICU overrides (1.0%) used the reason "Inaccurate warning," with 93 of these overrides associated with our included alert types. Sixty-one of these overrides (66%) were identified to be appropriate. Twenty-one of 30 (70%) dose alert overrides were appropriate. Forty of 48 drug-allergy alert overrides (83%) were appropriate, for reasons ranging from prior tolerance ( n  = 30) to inaccurate ingredient matches ( n  = 5). None of the 15 DDI overrides were appropriate.  The "Inaccurate warning" reason was selectively used by a small proportion of providers and overrides using this reason identified important opportunities to reduce excess alerts. Potential opportunities include improved evaluation of dosing mechanisms based on patient characteristics, inclusion of institutional dosing protocols to alert logic, and evaluation of a patient's prior tolerance to a medication that they have a documented allergy for. This resource is not yet routinely used for alert tailoring at our institution but may prove to be a valuable resource to evaluate available alerts. Schattauer GmbH Stuttgart.

Quantitative evaluation of bone resorption activity of osteoclast-like cells by measuring calcium phosphate resorbing area using incubator-facilitated and video-enhanced microscopy.

PubMed

Morimoto, Yoshitaka; Hoshino, Hironobu; Sakurai, Takashi; Terakawa, Susumu; Nagano, Akira

2009-04-01

Quantitative evaluation of the ability of bone resorption activity in live osteoclast-like cells (OCLs) has not yet been reported on. In this study, we observed the sequential morphological change of OCLs and measured the resorbing calcium phosphate (CP) area made by OCLs alone and with the addition of elcatonin utilizing incubator facilitated video-enhanced microscopy. OCLs, which were obtained from a coculture of ddy-mouse osteoblastic cells and bone marrow cells, were cultured on CP-coated quartz cover slips. The CP-free area increased constantly in the OCLs alone, whereas it did not increase after the addition of elcatonin. This study showed that analysis of the resorbed areas under the OCL body using this method enables the sequential quantitative evaluation of the bone resorption activity and the effect of several therapeutic agents on bone resorption in vitro.

Comparison of the inhibitory effects of tolcapone and entacapone against human UDP-glucuronosyltransferases

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lv, Xia

2016-06-15

Tolcapone and entacapone are two potent catechol-O-methyltransferase (COMT) inhibitors with a similar skeleton and displaying similar pharmacological activities. However, entacapone is a very safe drug used widely in the treatment of Parkinson's disease, while tolcapone is only in limited use for Parkinson's patients and needs careful monitoring of hepatic functions due to hepatotoxicity. This study aims to investigate and compare the inhibitory effects of entacapone and tolcapone on human UDP-glucosyltransferases (UGTs), as well as to evaluate the potential risks from the view of drug-drug interactions (DDI). The results demonstrated that both tolcapone and entacapone exhibited inhibitory effects on UGT1A1, UGT1A7,more » UGT1A9 and UGT1A10. In contrast to entacapone, tolcapone exhibited more potent inhibitory effects on UGT1A1, UGT1A7, and UGT1A10, while their inhibitory potentials against UGT1A9 were comparable. It is noteworthy that the inhibition constants (K{sub i}) of tolcapone and entacapone against bilirubin-O-glucuronidation in human liver microsomes (HLM) are determined as 0.68 μM and 30.82 μM, respectively, which means that the inhibition potency of tolcapone on UGT1A1 mediated bilirubin-O-glucuronidation in HLM is much higher than that of entacapone. Furthermore, the potential risks of tolcapone or entacapone via inhibition of human UGT1A1 were quantitatively predicted by the ratio of the areas under the plasma drug concentration-time curve (AUC). The results indicate that tolcapone may result in significant increase in AUC of bilirubin or the drugs primarily metabolized by UGT1A1, while entacapone is unlikely to cause a significant DDI through inhibition of UGT1A1. - Highlights: • Tolcapone and entacapone exhibited preferential inhibition against UGT1A enzymes. • In contrast to entacapone, tolcapone exhibited more potent inhibitory effects on human UGT1A1, 1 A7 and 1 A10. • Tolcapone may lead to significant increase in AUC of bilirubin. • This study provided new insights into the underlying mechanisms of tolcapone induced hepatotoxicity.« less

Symposium on Turbulence (12th) Held in Rolla, Missouri on 24-26 September 1990

DTIC Science & Technology

1992-11-01

over Zrag Reduc.,ng Surraces.’ 3:0pm S.-merments on :rre :ý!ec: ot ’Aean ’:ow ~jnsreao:- A. :3. Scnwarzvan Manen . R. Hoogstze".n. C. Stouthart. mess on...Laooratory. the Netnertancs: and M. van Lent. FoKker Aircrart S.V. 12= a3J. ’trge-=ddy Simulation of Turmuient Reac:ting P•umes. 11:20 a.n. ’A New...20 a&m. "Vortex Street in a Confined Slurry Flow." C. 0. Popiell andi Scalar Bisoet-ra.’ J. q. Heirinn, National Canter and 0. F. Van DOe Merwo

Advances in Anisotropic Materials for Optical Switching

DTIC Science & Technology

2010-09-16

polarization oflight, Figure 2(b)u.14,18.19, \\,/::1: 1 11 1" ~~§~ I ) \\111~~l\\ I .~~t~· . r illii I ’pQ~~rJ 1’/\\ ~~ \\, ,\\1 ,\\ ~ \\\\ .~: (a) (b) Fig. 2...CW and pulsed beams (materials containi ng two benzcne rings with donor·acccptor, or push·pull , ff-nC] conjugation, characte ri zed by r - I s...ioll, characterized by r - 0.00 I s) tError! Dookm.rk not ddiDtd.] . Azo LCs that combine the high photosensitivity of azobenzenes with the high

Assessment of drug-drug interaction potential between ceritinib and proton pump inhibitors in healthy subjects and in patients with ALK-positive non-small cell lung cancer.

PubMed

Lau, Yvonne Y; Gu, Wen; Lin, Tiffany; Viraswami-Appanna, Kalyanee; Cai, Can; Scott, Jeffrey W; Shi, Michael

2017-06-01

The impact of proton pump inhibitors (PPIs) on the pharmacokinetics (PK) and efficacy of ceritinib was evaluated. A healthy subject drug-drug interaction (DDI) study was conducted to assess the effect of esomeprazole on the PK of a single 750 mg dose of ceritinib. To further investigate the impact of PPIs on the PK and efficacy of ceritinib in ALK-positive cancer patients, two subgroup analyses were performed. Analysis 1 evaluated ceritinib steady-state trough concentration (C trough,ss ) and overall response rate (ORR) by concomitant use of PPIs in patients from the ASCEND-1, -2, and -3 studies; analysis 2 evaluated ceritinib single-dose and steady-state AUC 0-24h and C max by concomitant PPI use in patients from ASCEND-1 using a definition of PPI usage similar to that used in the healthy subject study. In the healthy subject study, co-administration of a single 750 mg dose of ceritinib with esomeprazole 40 mg for 6 days decreased ceritinib AUC 0-∞ by 76% and C max by 79%. However, based on subgroup analysis 1, patients had similar C trough,ss and ORR regardless of concomitant PPI usage. Based on analysis 2, co-administration of a single 750 mg ceritinib dose with PPIs for 6 days in patients suggested less effect on ceritinib exposure than that observed in healthy subjects as AUC 0-24h decreased by 30% and C max decreased by 25%. No clinically meaningful effect on steady-state exposure was observed after daily dosing. Long-term administration of ceritinib with PPIs does not adversely affect the PK and efficacy of ceritinib in ALK-positive cancer patients.

Transporter-Enzyme Interplay: Deconvoluting Effects of Hepatic Transporters and Enzymes on Drug Disposition Using Static and Dynamic Mechanistic Models.

PubMed

Varma, Manthena V; El-Kattan, Ayman F

2016-07-01

A large body of evidence suggests hepatic uptake transporters, organic anion-transporting polypeptides (OATPs), are of high clinical relevance in determining the pharmacokinetics of substrate drugs, based on which recent regulatory guidances to industry recommend appropriate assessment of investigational drugs for the potential drug interactions. We recently proposed an extended clearance classification system (ECCS) framework in which the systemic clearance of class 1B and 3B drugs is likely determined by hepatic uptake. The ECCS framework therefore predicts the possibility of drug-drug interactions (DDIs) involving OATPs and the effects of genetic variants of SLCO1B1 early in the discovery and facilitates decision making in the candidate selection and progression. Although OATP-mediated uptake is often the rate-determining process in the hepatic clearance of substrate drugs, metabolic and/or biliary components also contribute to the overall hepatic disposition and, more importantly, to liver exposure. Clinical evidence suggests that alteration in biliary efflux transport or metabolic enzymes associated with genetic polymorphism leads to change in the pharmacodynamic response of statins, for which the pharmacological target resides in the liver. Perpetrator drugs may show inhibitory and/or induction effects on transporters and enzymes simultaneously. It is therefore important to adopt models that frame these multiple processes in a mechanistic sense for quantitative DDI predictions and to deconvolute the effects of individual processes on the plasma and hepatic exposure. In vitro data-informed mechanistic static and physiologically based pharmacokinetic models are proven useful in rationalizing and predicting transporter-mediated DDIs and the complex DDIs involving transporter-enzyme interplay. © 2016, The American College of Clinical Pharmacology.

Absence of a Universal Mechanism of Mitochondrial Toxicity by Nucleoside Analogs▿

PubMed Central

Lund, Kaleb C.; Peterson, LaRae L.; Wallace, Kendall B.

2007-01-01

Nucleoside analogs are associated with various mitochondrial toxicities, and it is becoming increasingly difficult to accommodate these differences solely in the context of DNA polymerase gamma inhibition. Therefore, we examined the toxicities of zidovudine (AZT) (10 and 50 μM; 2.7 and 13.4 μg/ml), didanosine (ddI) (10 and 50 μM; 2.4 and 11.8 μg/ml), and zalcitabine (ddC) (1 and 5 μM; 0.21 and 1.1 μg/ml) in HepG2 and H9c2 cells without the presumption of mitochondrial DNA (mtDNA) depletion. Ethidium bromide (EtBr) (0.5 μg/ml; 1.3 μM) was used as a positive control. AZT treatment resulted in metabolic disruption (increased lactate and superoxide) and increased cell mortality with decreased proliferation, while mtDNA remained unchanged or increased (HepG2 cells; 50 μM AZT). ddC caused pronounced mtDNA depletion in HepG2 cells but not in H9c2 cells and increased mortality in HepG2 cells, but no significant metabolic disruption in either cell type. ddI caused a moderate depletion of mtDNA in both cell types but showed no other effects. EtBr exposure resulted in metabolic disruption, increased cell mortality with decreased cell proliferation, and mtDNA depletion in both cell types. We conclude that nucleoside analogs display unique toxicities within and between culture models, and therefore, care should be taken when generalizing about the mechanisms of nucleoside reverse transcriptase inhibitor toxicity. Additionally, mtDNA abundance does not necessarily correlate with metabolic disruption, especially in cell culture; careful discernment is recommended in this regard. PMID:17470651

Absence of a universal mechanism of mitochondrial toxicity by nucleoside analogs.

PubMed

Lund, Kaleb C; Peterson, LaRae L; Wallace, Kendall B

2007-07-01

Nucleoside analogs are associated with various mitochondrial toxicities, and it is becoming increasingly difficult to accommodate these differences solely in the context of DNA polymerase gamma inhibition. Therefore, we examined the toxicities of zidovudine (AZT) (10 and 50 microM; 2.7 and 13.4 microg/ml), didanosine (ddI) (10 and 50 microM; 2.4 and 11.8 microg/ml), and zalcitabine (ddC) (1 and 5 microM; 0.21 and 1.1 microg/ml) in HepG2 and H9c2 cells without the presumption of mitochondrial DNA (mtDNA) depletion. Ethidium bromide (EtBr) (0.5 microg/ml; 1.3 microM) was used as a positive control. AZT treatment resulted in metabolic disruption (increased lactate and superoxide) and increased cell mortality with decreased proliferation, while mtDNA remained unchanged or increased (HepG2 cells; 50 microM AZT). ddC caused pronounced mtDNA depletion in HepG2 cells but not in H9c2 cells and increased mortality in HepG2 cells, but no significant metabolic disruption in either cell type. ddI caused a moderate depletion of mtDNA in both cell types but showed no other effects. EtBr exposure resulted in metabolic disruption, increased cell mortality with decreased cell proliferation, and mtDNA depletion in both cell types. We conclude that nucleoside analogs display unique toxicities within and between culture models, and therefore, care should be taken when generalizing about the mechanisms of nucleoside reverse transcriptase inhibitor toxicity. Additionally, mtDNA abundance does not necessarily correlate with metabolic disruption, especially in cell culture; careful discernment is recommended in this regard.

Extracting Drug-Drug Interactions with Word and Character-Level Recurrent Neural Networks

PubMed Central

Kavuluru, Ramakanth; Rios, Anthony; Tran, Tung

2017-01-01

Drug-drug interactions (DDIs) are known to be responsible for nearly a third of all adverse drug reactions. Hence several current efforts focus on extracting signal from EMRs to prioritize DDIs that need further exploration. To this end, being able to extract explicit mentions of DDIs in free text narratives is an important task. In this paper, we explore recurrent neural network (RNN) architectures to detect and classify DDIs from unstructured text using the DDIExtraction dataset from the SemEval 2013 (task 9) shared task. Our methods are in line with those used in other recent deep learning efforts for relation extraction including DDI extraction. However, to our knowledge, we are the first to investigate the potential of character-level RNNs (Char-RNNs) for DDI extraction (and relation extraction in general). Furthermore, we explore a simple but effective model bootstrapping method to (a). build model averaging ensembles, (b). derive confidence intervals around mean micro-F scores (MMF), and (c). assess the average behavior of our methods. Without any rule based filtering of negative examples, a popular heuristic used by most earlier efforts, we achieve an MMF of 69.13. By adding simple replicable heuristics to filter negative instances we are able to achieve an MMF of 70.38. Furthermore, our best ensembles produce micro F-scores of 70.81 (without filtering) and 72.13 (with filtering), which are superior to metrics reported in published results. Although Char-RNNs turnout to be inferior to regular word based RNN models in overall comparisons, we find that ensembling models from both architectures results in nontrivial gains over simply using either alone, indicating that they complement each other. PMID:29034375

Fish oil prevents sucrose-induced fatty liver but exacerbates high-safflower oil-induced fatty liver in ddy mice.

PubMed

Yamazaki, Tomomi; Nakamori, Akiko; Sasaki, Eriko; Wada, Satoshi; Ezaki, Osamu

2007-12-01

Diets high in sucrose/fructose or fat can result in hepatic steatosis (fatty liver). We analyzed the effects of dietary fish oil on fatty liver induced by sucrose, safflower oil, and butter in ddY mice. In experiment I, mice were fed a high-starch diet [70 energy% (en%) starch] plus 20% (wt/wt) sucrose in the drinking water or fed a high-safflower oil diet (60 en%) for 11 weeks. As a control, mice were fed a high-starch diet with drinking water. Fish oil (10 en%) was either supplemented or not. Mice supplemented with sucrose or fed safflower oil showed a 1.7-fold or 2.2-fold increased liver triglyceride content, respectively, compared with that of control mice. Fish oil completely prevented sucrose-induced fatty liver, whereas it exacerbated safflower oil-induced fatty liver. Sucrose increased SREBP-1c and target gene messenger RNAs (mRNAs), and fish oil completely inhibited these increases. In experiment II, mice were fed a high-safflower oil or a high-butter diet, with or without fish oil supplementation. Fish oil exacerbated safflower oil-induced fatty liver but did not affect butter-induced fatty liver. Fish oil increased expression of peroxisome proliferator-activated receptor gamma (PPARgamma) and target CD36 mRNA in safflower oil-fed mice. These increases were not observed in sucrose-supplemented or butter-fed mice. The effects of dietary fish oil on fatty liver differ according to the cause of fatty liver; fish oil prevents sucrose-induced fatty liver but exacerbates safflower oil-induced fatty liver. The exacerbation of fatty liver may be due, at least in part, to increased expression of liver PPARgamma.

Position-aware deep multi-task learning for drug-drug interaction extraction.

PubMed

Zhou, Deyu; Miao, Lei; He, Yulan

2018-05-01

A drug-drug interaction (DDI) is a situation in which a drug affects the activity of another drug synergistically or antagonistically when being administered together. The information of DDIs is crucial for healthcare professionals to prevent adverse drug events. Although some known DDIs can be found in purposely-built databases such as DrugBank, most information is still buried in scientific publications. Therefore, automatically extracting DDIs from biomedical texts is sorely needed. In this paper, we propose a novel position-aware deep multi-task learning approach for extracting DDIs from biomedical texts. In particular, sentences are represented as a sequence of word embeddings and position embeddings. An attention-based bidirectional long short-term memory (BiLSTM) network is used to encode each sentence. The relative position information of words with the target drugs in text is combined with the hidden states of BiLSTM to generate the position-aware attention weights. Moreover, the tasks of predicting whether or not two drugs interact with each other and further distinguishing the types of interactions are learned jointly in multi-task learning framework. The proposed approach has been evaluated on the DDIExtraction challenge 2013 corpus and the results show that with the position-aware attention only, our proposed approach outperforms the state-of-the-art method by 0.99% for binary DDI classification, and with both position-aware attention and multi-task learning, our approach achieves a micro F-score of 72.99% on interaction type identification, outperforming the state-of-the-art approach by 1.51%, which demonstrates the effectiveness of the proposed approach. Copyright © 2018 Elsevier B.V. All rights reserved.

A study of potential pharmacokinetic and pharmacodynamic interactions between dextromethorphan/quinidine and memantine in healthy volunteers.

PubMed

Pope, Laura E; Schoedel, Kerri A; Bartlett, Cynthia; Sellers, Edward M

2012-08-01

Dextromethorphan/quinidine (DMQ) is the first agent indicated for the treatment of pseudobulbar affect. Dextromethorphan, the active ingredient, is a low-affinity, uncompetitive N-methyl-D-aspartate (NMDA) receptor antagonist. This study evaluated the potential for a drug-drug interaction (DDI) of DMQ with memantine, which is also an NMDA receptor antagonist. This open-label, randomized, parallel-group study enrolled healthy adults who were randomized into one of two treatment groups. Group 1 subjects were administered memantine at a starting dose of 5 mg once daily, which was titrated over a 3-week period to a dose of 10 mg twice daily (every 12 hours) and continued for another 11 days to attain steady state; DMQ 30 mg (dextromethorphan 30 mg/quinidine 30 mg) every 12 hours was then added for a further 8 days. Group 2 subjects received DMQ 30 mg every 12 hours for 8 days to attain steady state; memantine was then added, titrated on the same schedule as in group 1, and continued at 10 mg every 12 hours for an additional 11 days. Pharmacokinetic blood sampling was performed to assess the primary endpoints of the 90% confidence intervals (CIs) for the geometric mean ratios of the areas under the plasma concentration-time curves (AUCs) for memantine, dextromethorphan, dextrorphan - the dextromethorphan metabolite - and quinidine during concomitant therapy versus monotherapy. Safety/tolerability and pharmacodynamic variables were also assessed. A total of 52 subjects were randomized. In both group 1 (n = 23) and group 2 (n = 29), the 90% CIs for the ratios of the AUCs during concomitant therapy versus monotherapy were within the predefined range to indicate similarity (0.8-1.25) for memantine, dextromethorphan and dextrorphan, indicating no pharmacokinetic DDI. The 90% CI for the AUC ratio for quinidine was slightly above the predefined range; however, the mean AUC increased by only 25%. In both groups, incidence of adverse events was similar, and pharmacodynamic variables were either similar or slightly improved with DMQ added to memantine and memantine added to DMQ, compared to monotherapy with either agent. Minimal pharmacokinetic and pharmacodynamic interactions were observed between memantine and DMQ, suggesting they can be coadministered without dose adjustment.

Frequency of laboratory measurement and hyperkalaemia in hospitalised patients using serum potassium concentration increasing drugs.

PubMed

Uijtendaal, Esther V; Zwart-van Rijkom, Jeannette E F; van Solinge, Wouter W; Egberts, Toine C G

2011-09-01

Although, drug-drug interactions (DDIs) between potassium-increasing drugs (PIDs) are known risk factors for developing hyperkalaemia, not much is known about their risk and management strategies during hospitalisation. This study examines the frequency of serum potassium measurements and hyperkalaemia in hospitalised patients, based on the use of one or more PIDs, and the determinants thereof. Adult patients hospitalised in the University Medical Centre Utrecht between 2006 and 2008 were included in this cross-sectional study. The frequency of serum potassium measurements and of hyperkalaemia were compared between patients using only one PID at a time (monotherapy group) and patients using two or more PIDs concomitantly (interaction group). The determinants studied were renal failure, diabetes mellitus, use of diuretics, type of DDI, start of the PIDs within the hospital versus continued home medication and medical speciality. Serum potassium was measured more frequently in the interaction group than in the monotherapy group [67 vs. 56%; relative risk (RR) 1.19, 95% confidence interval (CI) 1.14-1.24] and the risk of hyperkalaemia was also increased in the interaction group (9.9 vs. 5.9%, RR 1.7, 95% CI 1.3-2.1). The combination of potassium-sparing diuretics plus a potassium supplement, start of the PID within the hospital and hospitalisation in non-internal medicine departments was associated with higher relative risk estimates for hyperkalaemia. Among our patient cohort, even when physicians received a direct pop-up to monitor serum potassium levels when prescribing two PIDs concomitantly, serum potassium levels were not measured in 33% of patients, and 10% of patients developed hyperkalaemia. Improved management strategies and/or clinical decision-support systems are needed to decrease the frequency of hyperkalaemia following DDIs.

Electrochemical Synthesis and Kinetic Evaluation of Electrooxidation of Acetaminophen in the Presence of Antidepressant Drugs

PubMed Central

Nematollahi, Davood; Feyzi Barnaji, Bahareh; Amani, Ameneh

2015-01-01

With the aim of obtaining information about drug-drug interaction (DDI) between acetaminophen and some of antidepressant drugs (fluoxetine, sertraline and nortriptyline), in the present work we studied the electrochemical oxidation of acetaminophen (paracetamol) in the presence of these drugs by means of cyclic voltammetry and Controlled-potential coulometry. The reaction between N-acetyl-p-benzoquinone-imine (NAPQI) produced from electrooxidation of acetaminophen and antidepressant drugs (see scheme 1) cause to reduce the concentration of NAPQI and decreases the effective concentration of antidepressants. The cyclic voltammetric data were analyzed by digital simulation to measure the homogeneous parameters for the suggesting electrode mechanism. The calculated observed homogeneous rate constants (kobs) for the reaction of electrochemically generated N-acetyl-para benzoquinn-imine with antidepressant drugs was found to vary in the order kobsnortriptyline > kobssertraline > kobsfluxetine at biological pH. PMID:26664378

[The use of auto mode switching in patients with sick sinus syndrome].

PubMed

Vlasínová, J

2005-01-01

At present the dual chamber pacing, originally developed for patients with AV blockades, is widely used also for patients with Sick sinus syndrome (tachycardic-bradycardic type). But these patients often cause therapeutical problems to their physicians. In these cases either antiarrhythmic therapy is necessary to prevent recurrent supraventricular tachycardias (which are cause of rapid ventricular pacing) or in the case of failure of AA therapy the pacing mode has to be changed to DDI/R, which excludes physiological VAT pacing. The Auto Mode Switching (AMS) function ensures adequate ventricular pacing rate in the time of SV arrhythmias. Effects of dual chamber pacemakers equipped with AMS were studied in a group of patients with paroxysmal atrial fibrilation and/or atrial flutter. Therapy brings effects in lower of expenses due to less frequent visits at the physician, lower rate of rehospitalizations and lower need for powerful AA therapy.

Comparison of Forecast and Observed Energetics

NASA Technical Reports Server (NTRS)

Baker, W. E.; Brin, Y.

1984-01-01

An energetics analysis scheme was developed to compare the observed kinetic energy balance over North America with that derived from forecast fields of the GLAS fourth order model for the 13 to 15 January 1979 cyclone case. It is found that: (1) the observed and predicted kinetic energy and eddy conversion are in good qualitative agreement, although the model eddy conversion tends to be 2 to 3 times stronger than the observed values. The eddy conversion which is stronger in the 12 h forecast than in observations and may be due to several factors is studied; (2) vertical profiles of kinetic energy generation and dissipation exhibit lower and upper tropospheric maxima in both the forecast and observations; (3) a lag in the observational analysis with the maximum in the observed kinetic energy occurring at 0000 GMT 14 January over the same region as the maximum ddy conversion 12 h earlier is noted.

Aspirin and probenecid inhibit organic anion transporter 3-mediated renal uptake of cilostazol and probenecid induces metabolism of cilostazol in the rat.

PubMed

Wang, Chong; Wang, Changyuan; Liu, Qi; Meng, Qiang; Cang, Jian; Sun, Huijun; Peng, Jinyong; Ma, Xiaochi; Huo, Xiaokui; Liu, Kexin

2014-06-01

This study aimed to evaluate the transporter-mediated renal excretion mechanism for cilostazol and to characterize the mechanism of drug-drug interaction (DDI) between cilostazol and aspirin or probenecid. Concentrations of cilostazol and its metabolites OPC-13015 [6-[4-(1-cyclohexyl-1H-tetrazol-5-yl)butoxy]-2(1H)-quinolinone] and OPC-13213 [3,4-dihydro-6-[4-[1-(trans-4-hydroxycyclohexyl)-1H-tetrazol-5-yl]butoxy]-2-(1H)-quinolinone] in rat biologic or cell samples were measured by liquid chromatography-tandem mass spectrometry. Coadministration with probenecid, benzylpenicillin, or aspirin decreased the cumulative urinary excretion of cilostazol and renal clearance. Concentrations of cilostazol and OPC-13213 in plasma decreased, and the concentration of OPC-13015 increased in the presence of probenecid. By contrast, rat plasma cilostazol, in combination with benzylpenicillin or aspirin, sharply increased, and concentrations of OPC-13015 and OPC-13213 did not change. In urine, OPC-13015 was below the level of detection. The cumulative urinary excretion of OPC-13213 decreased in the presence of probenecid, benzylpenicillin, or aspirin. Cilostazol was distributed in the kidney and liver, with tissue to plasma partition coefficient (Kp) values of 8.4 ml/g and 16.3 ml/g, respectively. Probenecid and aspirin reduced cilostazol distribution in the kidney. Probenecid did not affect cilostazol metabolism in the kidney but increased cilostazol metabolism in the liver, and aspirin had no effect on cilostazol metabolism. Benzylpenicillin, aspirin, and cyclo-trans-4-l-hydroxyprolyl-l-serine (JBP485) reduced cilostazol uptake in kidney slices and human organic anion transporter 3 (hOAT3)-human embryonic kidney 293 (HEK293) cells, whereas p-aminohippuric acid did not. Compared with the vector, hOAT3-HEK293 cells accumulated more cilostazol, whereas hOAT1-HEK293 cells did not. OAT3 and Oat3 play a major role in cilostazol renal excretion, whereas OAT1 and Oat1 do not. Oat3 and Cyp3a are both targets of the DDI between cilostazol and probenecid. Aspirin inhibits OAT3-mediated uptake of cilostazol and does not influence cilostazol metabolism.

Discovery of novel DAPY-IAS hybrid derivatives as potential HIV-1 inhibitors using molecular hybridization based on crystallographic overlays.

PubMed

Huang, Boshi; Wang, Xueshun; Liu, Xinhao; Chen, Zihui; Li, Wanzhuo; Sun, Songkai; Liu, Huiqing; Daelemans, Dirk; De Clercq, Erik; Pannecouque, Christophe; Zhan, Peng; Liu, Xinyong

2017-08-15

Crystallographic overlap studies and pharmacophoric analysis indicated that diarylpyrimidine (DAPY)-based HIV-1 NNRTIs showed a similar binding mode and pharmacophoric features as indolylarylsulfones (IASs), another class of potent NNRTIs. Thus, a novel series of DAPY-IAS hybrid derivatives were identified as newer NNRTIs using structure-based molecular hybridization. Some target compounds exhibited moderate activities against HIV-1 IIIB strain, among which the two most potent inhibitors possessed EC 50 values of 1.48μM and 1.61μM, respectively. They were much potent than the reference drug ddI (EC 50 =76.0μM) and comparable to 3TC (EC 50 =2.54μM). Compound 7a also exhibited the favorable selectivity index (SI=80). Preliminary structure-activity relationships (SARs), structure-cytotoxicity relationships, molecular modeling studies, and in silico calculation of physicochemical properties of these new inhibitors were also discussed. Copyright © 2017 Elsevier Ltd. All rights reserved.

Medication overuse headache: withdrawal and prophylactic therapeutic regimen.

PubMed

Trucco, Marco; Meineri, Piero; Ruiz, Luigi; Gionco, Maurizio

2010-06-01

Medication overuse headache (MOH) is a secondary headache, whose diagnostic criteria were settled by the Second Edition of the International Classification of Headache Disorders and its subsequent revisions. Its diagnosis and treatment represent a growing problem worldwide and a challenge for headache specialists. The aim of this study was to evaluate the efficacy of a therapeutic regimen for withdrawal of the overused drug and prophylaxis of headache in a population of patients suffering from MOH in 8 hospitals of Piemonte - Liguria - Valle d'Aosta. Seventy patients, 58 females (82.9%) and 12 males (17.1%), mean age at observation 51.04 +/- 12.59 years, affected by MOH following International Headache Society diagnostic revised criteria were treated as inpatients (n = 40) or in Day Hospital (n = 30). Headache Index (HI) and Daily Drug Intake (DDI) were used for evaluating the severity of headache and medication overuse. The patients were treated by abrupt discontinuation of the overused drug and by a therapeutic protocol including i.v. hydration, dexhamethasone, metoclopramide, and benzodiazepines for 7-15 days. Prophylactic medication was started at the beginning of therapeutic protocol. Patients underwent follow-up controls 1, 3, and 6 months after discharge. The initial diagnosis was MOH in all patients included in the study. The overused medications were simple analgesics in 18 cases (25.7%), combination analgesics in 26 cases (37.1%), triptans alone in 9 cases (12.9%), or in combination with analgesics in 13 cases (18.6%), and ergot derivatives (in combination) in 4 cases (5.7%). We collected data from 59 patients at first follow-up (1 month), 56 after 3 months, and 42 after 6 months. Mean HI was 0.92 at admission, 0.19 at discharge, 0.35 after 30 days, 0.39 after 3 months, and 0.42 after 6 months. Mean DDI was 2.72 at admission, 0.22 at discharge, 0.31 after 1 month, 0.38 after 3 months, and 0.47 after 6 months. These results proved to be highly statistically significant. The protocol was generally effective, safe, and well-tolerated. The results tend to remain stable with time, and seem to be encouraging about long-term use of this therapeutic protocol on a larger number of patients suffering from MOH.

Assessment of inhibitory effects on major human cytochrome P450 enzymes by spasmolytics used in the treatment of overactive bladder syndrome.

PubMed

Dahlinger, Dominik; Aslan, Sevinc; Pietsch, Markus; Frechen, Sebastian; Fuhr, Uwe

2017-07-01

The objective of this study was to examine the inhibitory potential of darifenacin, fesoterodine, oxybutynin, propiverine, solifenacin, tolterodine and trospium chloride on the seven major human cytochrome P450 enzymes (CYP) by using a standardized and validated seven-in-one cytochrome P450 cocktail inhibition assay. An in vitro cocktail of seven highly selective probe substrates was incubated with human liver microsomes and varying concentrations of the seven test compounds. The major metabolites of the probe substrates were simultaneously analysed using a validated liquid chromatography tandem mass spectrometry (LC-MS/MS) method. Enzyme kinetics were estimated by determining IC 50 and K i values via nonlinear regression. Obtained K i values were used for predictions of potential clinical impact of the inhibition using a static mechanistic prediction model. In this study, 49 IC 50 experiments were conducted. In six cases, IC 50 values lower than the calculated threshold for drug-drug interactions (DDIs) in the gut wall were observed. In these cases, no increase in inhibition was determined after a 30 min preincubation. Considering a typical dosing regimen and applying the obtained K i values of 0.72 µM (darifenacin, 15 mg daily) and 7.2 µM [propiverine, 30 mg daily, immediate release (IR)] for the inhibition of CYP2D6 yielded a predicted 1.9-fold and 1.4-fold increase in the area under the curve (AUC) of debrisoquine (CYP2D6 substrate), respectively. Due to the inhibition of the particular intestinal CYP3A4, the obtained K i values of 14 µM of propiverine (30 mg daily, IR) resulted in a predicted doubling of the AUC for midazolam (CYP3A4 substrate). In vitro / in vivo extrapolation based on pharmacokinetic data and the conducted screening experiments yielded similar effects of darifenacin on CYP2D6 and propiverine on CYP3A4 as obtained in separately conducted in vivo DDI studies. As a novel finding, propiverine was identified to potentially inhibit CYP2D6 at clinically occurring concentrations.

Assessment of inhibitory effects on major human cytochrome P450 enzymes by spasmolytics used in the treatment of overactive bladder syndrome

PubMed Central

Dahlinger, Dominik; Aslan, Sevinc; Pietsch, Markus; Frechen, Sebastian; Fuhr, Uwe

2017-01-01

Background: The objective of this study was to examine the inhibitory potential of darifenacin, fesoterodine, oxybutynin, propiverine, solifenacin, tolterodine and trospium chloride on the seven major human cytochrome P450 enzymes (CYP) by using a standardized and validated seven-in-one cytochrome P450 cocktail inhibition assay. Methods: An in vitro cocktail of seven highly selective probe substrates was incubated with human liver microsomes and varying concentrations of the seven test compounds. The major metabolites of the probe substrates were simultaneously analysed using a validated liquid chromatography tandem mass spectrometry (LC-MS/MS) method. Enzyme kinetics were estimated by determining IC50 and Ki values via nonlinear regression. Obtained Ki values were used for predictions of potential clinical impact of the inhibition using a static mechanistic prediction model. Results: In this study, 49 IC50 experiments were conducted. In six cases, IC50 values lower than the calculated threshold for drug–drug interactions (DDIs) in the gut wall were observed. In these cases, no increase in inhibition was determined after a 30 min preincubation. Considering a typical dosing regimen and applying the obtained Ki values of 0.72 µM (darifenacin, 15 mg daily) and 7.2 µM [propiverine, 30 mg daily, immediate release (IR)] for the inhibition of CYP2D6 yielded a predicted 1.9-fold and 1.4-fold increase in the area under the curve (AUC) of debrisoquine (CYP2D6 substrate), respectively. Due to the inhibition of the particular intestinal CYP3A4, the obtained Ki values of 14 µM of propiverine (30 mg daily, IR) resulted in a predicted doubling of the AUC for midazolam (CYP3A4 substrate). Conclusions: In vitro/in vivo extrapolation based on pharmacokinetic data and the conducted screening experiments yielded similar effects of darifenacin on CYP2D6 and propiverine on CYP3A4 as obtained in separately conducted in vivo DDI studies. As a novel finding, propiverine was identified to potentially inhibit CYP2D6 at clinically occurring concentrations. PMID:28747995

The effect of paracetamol on 5 fluorouracil and bovine serum albumin interaction: A biophysical study

NASA Astrophysics Data System (ADS)

Dahiya, Vandana; Pal, Samanwita

2018-05-01

Serum Albumin is a major carrier protein and its binding with drugs is important to examine the change in pharmacokinetic properties due to interaction amongst drugs. In the present study we have attempted to understand the relevant drug-drug interaction (DDI) between two common drugs viz, paracetamol, an anti-inflammatory and fluorouracil, an anti-cancer drug. In-vitro spectroscopic methods viz., fluorescence quenching and UV-vis absorption have been employed for the drug-bovine serum albumin (BSA) complexes studies. The binding parameters and quenching constants have been determined for BSA-Paracetamol and BSA-5Fluorouracil complex according to literature models. It is also predicted from the quenching studies that BSA-5Fluorouracil is a stronger complex than BSA-Paracetamol. On the other hand paracetamol can alter binding affinity of 5Fluorouracil towards BSA. Hence it becomes clear that although the drugs could be administered simultaneously but they influence each other's binding with protein in a concentration dependent fashion. Further these results also indicate that availability of free 5Fluorouracil in blood may increase in presence of paracetamol.

In vitro characterization of sarizotan metabolism: hepatic clearance, identification and characterization of metabolites, drug-metabolizing enzyme identification, and evaluation of cytochrome p450 inhibition.

PubMed

Gallemann, Dieter; Wimmer, Elmar; Höfer, Constance C; Freisleben, Achim; Fluck, Markus; Ladstetter, Bernhard; Dolgos, Hugues

2010-06-01

In vitro biotransformation studies of sarizotan using human liver microsomes (HLM) showed aromatic and aliphatic monohydroxylation and dealkylation. Recombinant cytochromes P450 (P450) together with P450-selective inhibitors in HLM/hepatocyte cultures were used to evaluate the relative contribution of different P450s and revealed major involvement of CYP3A4, CYP2C9, CYP2C8, and CYP1A2 in sarizotan metabolism. The apparent K(m, u) and V(max) of sarizotan clearance, as investigated in HLM, were 9 microM and 3280 pmol/mg/min, predicting in vivo hepatic clearance of 0.94 l/h, which indicates that sarizotan is a low-clearance compound in humans and suggests nonsaturable metabolism at the targeted plasma concentration (< or =1 microM). This finding is confirmed by the reported human clearance (CL/F of 3.6-4.4 l/h) and by the dose-linear area under the curve increase observed with doses up to 25 mg. The inhibitory effect of sarizotan toward six major P450s was evaluated using P450-specific marker reactions in pooled HLM. K(i, u) values of sarizotan against CYP2C8, CYP2C19, and CYP3A4 were >10 microM, whereas those against CYP2D6 and CYP1A2 were 0.43 and 8.7 microM, respectively. Based on the estimates of sarizotan concentrations at the enzyme active sites, no clinically significant drug-drug interactions (DDIs) due to P450 inhibition are expected. This result has been confirmed in human DDI studies in which no inhibition of five major P450s was observed in terms of marker metabolite formation.

Incidence of potential drug interactions in a transplant centre setting and relevance of electronic alerts for clinical practice support.

PubMed

Polidori, Piera; Di Giorgio, Concetta; Provenzani, Alessio

2012-01-01

Adverse drug events may occur as a result of drug-drug interactions (DDIs). Information technology (IT) systems can be an important decision-making tool for healthcare workers to identify DDIs. The aim of the study is to analyse drug prescriptions in our main hospital units, in order to measure the incidence and severity of potential DDIs. The utility of clinical decision-support systems (CDSSs) and computerised physician order entry (CPOE) in term of alerts adherence was also assessed. DDIs were assessed using a Micromedex® healthcare series database. The system, adopted by the hospital, generates alerts for prescriptions with negative interactions and thanks to an 'acknowledgement function' it is possible to verify physician adherence to alerts. This function, although used previously, became mandatory from September 2010. Physician adherence to alerts and mean monthly incidence of potential DDIs in analysed units, before and after the mandatory 'acknowledgement function', were calculated. The intensive care unit (ICU) registered the greatest incidence of potential DDIs (49.0%), followed by the abdominal surgery unit and dialysis (43.4 and 42.0%, respectively). The cardiothoracic surgery unit (41.6%), step-down unit (38.3%) and post-anaesthesia care unit (30.0%) were comparable. The operating theatre and endoscopy registered the fewest potential DDIs (28.2 and 22.7%, respectively). Adherence to alerts after the 'acknowledgement function' increased by 25.0% in the ICU, 54.0% in the cardiothoracic surgery unit, 52.5% in the abdominal surgery unit, 58.0% in the stepdown unit, 67.0% in dialysis, 51.0% in endoscopy and 48.0% in the post-anaesthesia care unit. In the operating theatre, adherence to alerts decreased from 34.0 to 30.0%. The incidence of potential DDIs after mandatory use of the 'acknowledgement function' decreased slightly in endoscopy (-2.9%), the abdominal surgery unit (-2.7%), dialysis (-1.9%) and the step-down unit (-1.4%). Improving DDI alerts will improved patient safety by more appropriately alerting clinicians.

[Drug-drug interactions: interactions between xenobiotics].

PubMed

Haen, E

2014-04-01

Drug-drug interactions (DDI) are a major topic in programs for continuous medical education (CME). Many physicians are afraid of being trapped into charges of malpractice; however, DDI cannot be avoided in many cases. They belong to routine medical practice and it is often impossible to avoid them. Moreover, they do not just occur between drugs but between any kind of foreign substance (xenobiotica), such as food (e.g. grapefruit juice, broccoli, barbecue) as well as legal (e.g. tobacco smoke, caffeine and alcohol) and illegal drugs. Therefore, the medical challenge is not just to avoid any interaction. Instead the physician faces the question of how to proceed with drug treatment in the presence of such interactions. Based on the medical education a physician has to judge first of all whether there is a risk for interactions in the prescription being planned for an individual patient. The classification of interactions proposed in this article (PD1-PD4, PK1-PK3) might help as a sort of check list. For more detailed information the physician can then consult one of the many databases available on the internet, such as PSIAConline (http://www.psiac.de) and MediQ (http://www.mediq.ch). Pharmacokinetic interactions can be easily assessed, monitored and controlled by therapeutic drug monitoring (TDM). Besides these tools it is important to keep in mind that nobody knows everything; even physicians do not know everything. So take pride in asking someone who might help and for this purpose AGATE offers a drug information service AID (http://www.amuep-agate.de). Just good for nothing, without being based on any kind of medical approach are computer programs that judge prescriptions without taking into account a patient's individual peculiarities. In case these types of programs produce red exclamation marks or traffic lights to underline their judgment, they might even work in a contrapuntal way by just eliciting insecurity and fear.

Digital Photoplethysmography for Assessment of Arterial Stiffness: Repeatability and Comparison with Applanation Tonometry

PubMed Central

Östling, Gerd; Nilsson, Peter M.

2015-01-01

Introduction Arterial stiffness is an independent risk factor for cardiovascular morbidity and can be assessed by applanation tonometry by measuring pulse wave velocity (PWV) and augmentation index (AIX) by pressure pulse wave analysis (PWA). As an inexpensive and operator independent alternative, photoelectric plethysmography (PPG) has been introduced with analysis of the digital volume pulse wave (DPA) and its second derivatives of wave reflections. Objective The objective was to investigate the repeatability of arterial stiffness parameters measured by digital pulse wave analysis (DPA) and the associations to applanation tonometry parameters. Methods and Results 112 pregnant and non-pregnant individuals of different ages and genders were examined with SphygmoCor arterial wall tonometry and Meridian DPA finger photoplethysmography. Coefficients of repeatability, Bland-Altman plots, intraclass correlation coefficients and correlations to heart rate (HR) and body height were calculated for DPA variables, and the DPA variables were compared to tonometry variables left ventricular ejection time (LVET), PWV and AIX. No DPA variable showed any systematic measurement error or excellent repeatability, but dicrotic index (DI), dicrotic dilatation index (DDI), cardiac ejection elasticity index (EEI), aging index (AI) and second derivatives of the crude pulse wave curve, b/a and e/a, showed good repeatability. Overall, the correlations to AIX were better than to PWV, with correlations coefficients >0.70 for EEI, AI and b/a. Considering the level of repeatability and the correlations to tonometry, the overall best DPA parameters were EEI, AI and b/a. The two pansystolic time parameters, ejection time compensated (ETc) by DPA and LVET by tonometry, showed a significant but weak correlation. Conclusion For estimation of the LV function, ETc, EEI and b/a are suitable, for large artery stiffness EEI, and for small arteries DI and DDI. The only global parameter, AI, showed a high repeatability and the overall best correlations with AIX and PWV. PMID:26291079

Predicting domain-domain interaction based on domain profiles with feature selection and support vector machines

PubMed Central

2010-01-01

Background Protein-protein interaction (PPI) plays essential roles in cellular functions. The cost, time and other limitations associated with the current experimental methods have motivated the development of computational methods for predicting PPIs. As protein interactions generally occur via domains instead of the whole molecules, predicting domain-domain interaction (DDI) is an important step toward PPI prediction. Computational methods developed so far have utilized information from various sources at different levels, from primary sequences, to molecular structures, to evolutionary profiles. Results In this paper, we propose a computational method to predict DDI using support vector machines (SVMs), based on domains represented as interaction profile hidden Markov models (ipHMM) where interacting residues in domains are explicitly modeled according to the three dimensional structural information available at the Protein Data Bank (PDB). Features about the domains are extracted first as the Fisher scores derived from the ipHMM and then selected using singular value decomposition (SVD). Domain pairs are represented by concatenating their selected feature vectors, and classified by a support vector machine trained on these feature vectors. The method is tested by leave-one-out cross validation experiments with a set of interacting protein pairs adopted from the 3DID database. The prediction accuracy has shown significant improvement as compared to InterPreTS (Interaction Prediction through Tertiary Structure), an existing method for PPI prediction that also uses the sequences and complexes of known 3D structure. Conclusions We show that domain-domain interaction prediction can be significantly enhanced by exploiting information inherent in the domain profiles via feature selection based on Fisher scores, singular value decomposition and supervised learning based on support vector machines. Datasets and source code are freely available on the web at http://liao.cis.udel.edu/pub/svdsvm. Implemented in Matlab and supported on Linux and MS Windows. PMID:21034480

Physiologically based pharmacokinetic model of mechanism-based inhibition of CYP3A by clarithromycin.

PubMed

Quinney, Sara K; Zhang, Xin; Lucksiri, Aroonrut; Gorski, J Christopher; Li, Lang; Hall, Stephen D

2010-02-01

The prediction of clinical drug-drug interactions (DDIs) due to mechanism-based inhibitors of CYP3A is complicated when the inhibitor itself is metabolized by CYP3Aas in the case of clarithromycin. Previous attempts to predict the effects of clarithromycin on CYP3A substrates, e.g., midazolam, failed to account for nonlinear metabolism of clarithromycin. A semiphysiologically based pharmacokinetic model was developed for clarithromycin and midazolam metabolism, incorporating hepatic and intestinal metabolism by CYP3A and non-CYP3A mechanisms. CYP3A inactivation by clarithromycin occurred at both sites. K(I) and k(inact) values for clarithromycin obtained from in vitro sources were unable to accurately predict the clinical effect of clarithromycin on CYP3A activity. An iterative approach determined the optimum values to predict in vivo effects of clarithromycin on midazolam to be 5.3 microM for K(i) and 0.4 and 4 h(-1) for k(inact) in the liver and intestines, respectively. The incorporation of CYP3A-dependent metabolism of clarithromycin enabled prediction of its nonlinear pharmacokinetics. The predicted 2.6-fold change in intravenous midazolam area under the plasma concentration-time curve (AUC) after 500 mg of clarithromycin orally twice daily was consistent with clinical observations. Although the mean predicted 5.3-fold change in the AUC of oral midazolam was lower than mean observed values, it was within the range of observations. Intestinal CYP3A activity was less sensitive to changes in K(I), k(inact), and CYP3A half-life than hepatic CYP3A. This semiphysiologically based pharmacokinetic model incorporating CYP3A inactivation in the intestine and liver accurately predicts the nonlinear pharmacokinetics of clarithromycin and the DDI observed between clarithromycin and midazolam. Furthermore, this model framework can be applied to other mechanism-based inhibitors.

Identifying interactions between chemical entities in biomedical text.

PubMed

Lamurias, Andre; Ferreira, João D; Couto, Francisco M

2014-10-23

Interactions between chemical compounds described in biomedical text can be of great importance to drug discovery and design, as well as pharmacovigilance. We developed a novel system, \\"Identifying Interactions between Chemical Entities\\" (IICE), to identify chemical interactions described in text. Kernel-based Support Vector Machines first identify the interactions and then an ensemble classifier validates and classifies the type of each interaction. This relation extraction module was evaluated with the corpus released for the DDI Extraction task of SemEval 2013, obtaining results comparable to state-of-the-art methods for this type of task. We integrated this module with our chemical named entity recognition module and made the whole system available as a web tool at www.lasige.di.fc.ul.pt/webtools/iice.

Identifying interactions between chemical entities in biomedical text.

PubMed

Lamurias, Andre; Ferreira, João D; Couto, Francisco M

2014-12-01

Interactions between chemical compounds described in biomedical text can be of great importance to drug discovery and design, as well as pharmacovigilance. We developed a novel system, "Identifying Interactions between Chemical Entities" (IICE), to identify chemical interactions described in text. Kernel-based Support Vector Machines first identify the interactions and then an ensemble classifier validates and classifies the type of each interaction. This relation extraction module was evaluated with the corpus released for the DDI Extraction task of SemEval 2013, obtaining results comparable to stateof- the-art methods for this type of task. We integrated this module with our chemical named entity recognition module and made the whole system available as a web tool at www.lasige.di.fc.ul.pt/webtools/iice.

Rhabdomyolysis caused by the moderate CYP3A4 inhibitor fluconazole in a patient on stable atorvastatin therapy: a case report and literature review.

PubMed

Hsiao, S-H; Chang, H-J; Hsieh, T-H; Kao, S-M; Yeh, P-Y; Wu, T-J

2016-10-01

Rhabdomyolysis is a severe potential adverse drug reaction of statin therapy. We report a case of rhabdomyolysis due to drug-drug interaction (DDI) between atorvastatin and fluconazole and review the literature. A 70-year-old woman received atorvastatin for hyperlipidaemia without any problem for 4 years. When intravenous fluconazole was added for treating a fungal infection, rhabdomyolysis developed 2 weeks later. Removal of atorvastatin led to the resolution of her rhabdomyolysis. Our case demonstrates that in some subjects even a moderate CYP3A4 inhibitor such as fluconazole may lead to rhabdomyolysis in subjects receiving a statin. © 2016 John Wiley & Sons Ltd.

Preliminary results of a withdrawal and detoxification therapeutic regimen in patients with probable chronic migraine and probable medication overuse headache.

PubMed

Trucco, Marco; Meineri, Piero; Ruiz, Luigi

2005-09-01

Chronic migraine (CM) is an invalidating condition affecting a significant population of headache sufferers, frequently associated with medication overuse headache (MOH). Controlled trials and guidelines for the treatment of MOH are currently not available. We studied the efficacy of a therapeutic regimen for the withdrawal of the overused drug and detoxification in a sample of patients suffering from probable CM and probable MOH during admission in eight hospitals of Piemonte-Liguria-Valle d'Aosta. Fifty patients, 42 females (84%) and 8 males (16%), mean age at observation 50.66+/-13.08 years, affected by probable CM and daily medication overuse following IHS diagnostic criteria were treated as inpatients or in a day hospital. Headache index (HI) and daily drug intake (DDI) were used for evaluating the severity of headache and medication overuse. The patients were treated by abrupt discontinuation of the overused drug and by a therapeutic protocol including i.v. hydration, dexamethasone, metoclopramide and benzodiazepines for 7-10 days. Prophylactic medication was started immediately after admission. Analgesics or triptans were used under medical control only in cases of severe rebound headache. Diagnostic protocol included routine blood tests (at admission and at discharge), dosage of B12 and folic acid. Patients underwent follow-up controls one, three and six months after discharge. The initial diagnosis was probable CM in almost all patients included in the study (41 patients); in nine patients the diagnosis was not specified (coded only as CDH). The overused medications were simple analgesics in 17 cases (34%), combination analgesics in 19 cases (38%), triptans alone or with analgesics in 13 cases (26%) and ergotamine in 2 cases (4%). We collected data from 39 patients at first follow-up (1 month), 32 after 3 months and 14 after 6 months. Mean HI was 0.91 at admission, 0.22 at discharge, 0.38 after 30 days, 0.46 after 3 months and 0.48 after 6 months. Mean DDI was 2.80 at admission, 0.39 at discharge, 0.41 after 1 month, 0.52 after 3 months and 0.59 after 6 months. These results are on average positive and tend to remain stable with time. Although preliminary and obtained on a limited number of patients at 6-month follow-up, our results seem to be encouraging about the use of the proposed therapeutic protocol.

Heat sterilizable solid-propellant development

NASA Technical Reports Server (NTRS)

Kalfayan, S. H.

1981-01-01

The binders tested were polyurethanes made from two hydroxy-terminated polybutadienes, R-45 and Butarez HT, one hydroxy-terminated butadiene-acrylonitrile copolymer, Hycar 1300X 17, and a hydroxy-terminated prepolymer, Esterdiol 560, made from the dimerized fatty acid Empol 1010. The isocyanates used most extensively were isophorone diisocyanate (IPDI) and a polymeric diisocyanate, DDI. Stress relaxation was used to examine the chemical changes that took place in the binder when subjected to the sterilization temperatures. The thermal stability of the oxidizer, ammonium perchlorate (AP), was tested by thermogravimetry in the isothermal and nonisothermal modes. The effect of particle size, recrystallization, moisture content, and doping on the heat stability of AP could be evaluated by this method. The volatile degradation products, obtained when AP samples were aged at 135 C for prolonged periods, were analyzed by mass spectroscopy.

Drug-drug interaction predictions with PBPK models and optimal multiresponse sampling time designs: application to midazolam and a phase I compound. Part 1: comparison of uniresponse and multiresponse designs using PopDes.

PubMed

Chenel, Marylore; Bouzom, François; Aarons, Leon; Ogungbenro, Kayode

2008-12-01

To determine the optimal sampling time design of a drug-drug interaction (DDI) study for the estimation of apparent clearances (CL/F) of two co-administered drugs (SX, a phase I compound, potentially a CYP3A4 inhibitor, and MDZ, a reference CYP3A4 substrate) without any in vivo data using physiologically based pharmacokinetic (PBPK) predictions, population PK modelling and multiresponse optimal design. PBPK models were developed with AcslXtreme using only in vitro data to simulate PK profiles of both drugs when they were co-administered. Then, using simulated data, population PK models were developed with NONMEM and optimal sampling times were determined by optimizing the determinant of the population Fisher information matrix with PopDes using either two uniresponse designs (UD) or a multiresponse design (MD) with joint sampling times for both drugs. Finally, the D-optimal sampling time designs were evaluated by simulation and re-estimation with NONMEM by computing the relative root mean squared error (RMSE) and empirical relative standard errors (RSE) of CL/F. There were four and five optimal sampling times (=nine different sampling times) in the UDs for SX and MDZ, respectively, whereas there were only five sampling times in the MD. Whatever design and compound, CL/F was well estimated (RSE < 20% for MDZ and <25% for SX) and expected RSEs from PopDes were in the same range as empirical RSEs. Moreover, there was no bias in CL/F estimation. Since MD required only five sampling times compared to the two UDs, D-optimal sampling times of the MD were included into a full empirical design for the proposed clinical trial. A joint paper compares the designs with real data. This global approach including PBPK simulations, population PK modelling and multiresponse optimal design allowed, without any in vivo data, the design of a clinical trial, using sparse sampling, capable of estimating CL/F of the CYP3A4 substrate and potential inhibitor when co-administered together.

Impact of Experimental Conditions on the Evaluation of Interactions between Multidrug and Toxin Extrusion Proteins and Candidate Drugs.

PubMed

Lechner, Christian; Ishiguro, Naoki; Fukuhara, Ayano; Shimizu, Hidetada; Ohtsu, Naoko; Takatani, Masahito; Nishiyama, Kotaro; Washio, Ikumi; Yamamura, Norio; Kusuhara, Hiroyuki

2016-08-01

Multidrug and toxin extrusion transporters (MATEs) have a determining influence on the pharmacokinetic profiles of many drugs and are involved in several clinical drug-drug interactions (DDIs). Cellular uptake assays with recombinant cells expressing human MATE1 or MATE2-K are widely used to investigate MATE-mediated transport for DDI assessment; however, the experimental conditions and used test substrates vary among laboratories. We therefore initially examined the impact of three assay conditions that have been applied for MATE substrate and inhibitor profiling in the literature. One of the tested conditions resulted in significantly higher uptake rates of the three test substrates, [(14)C]metformin, [(3)H]thiamine, and [(3)H]1-methyl-4-phenylpyridinium (MPP(+)), but IC50 values of four tested MATE inhibitors varied only slightly among the three conditions (<2.5-fold difference). Subsequently, we investigated the uptake characteristics of the five MATE substrates: [(14)C]metformin, [(3)H]thiamine, [(3)H]MPP(+), [(3)H]estrone-3-sulfate (E3S), and rhodamine 123, as well as the impact of the used test substrate on the inhibition profiles of 10 MATE inhibitors at one selected assay condition. [(3)H]E3S showed atypical uptake characteristics compared with those observed with the other four substrates. IC50 values of the tested inhibitors were in a similar range (<4-fold difference) when [(14)C]metformin, [(3)H]thiamine, [(3)H]MPP(+), or [(3)H]E3S were used as substrates but were considerably higher with rhodamine 123 (9.8-fold and 4.1-fold differences compared with [(14)C]metformin with MATE1 and MATE2-K, respectively). This study demonstrated for the first time that the impact of assay conditions on IC50 determination is negligible, that kinetic characteristics differ among used test substrates, and that substrate-dependent inhibition exists for MATE1 and MATE2-K, giving valuable insight into the assessment of clinically relevant MATE-mediated DDIs in vitro. Copyright © 2016 by The American Society for Pharmacology and Experimental Therapeutics.

Immunohistochemical expression of hard tissue related factors in the mouse dental pulp after immediate teeth separation

PubMed Central

2011-01-01

We examined change of Runx2 and ALP expression in mouse tooth pulp which exposed to teeth separation experiment by immunohistochemistry as a model for conservative dentistry treatment. 8-week-old 36 male ddY mice were used and wedge was inserted between upper 1st and 2nd molars. The wedge was removed 30 minutes as well as 3 hours after the insertion and the samples were prepared extending up to 1 week of time period for regular histopathological and immunohistochemical examinations for ALP and Runx2 expression. The opposite sides without wedge insertion were taken as controls. In the control group pulp, weak expressions of Runx2 and ALP in the vessel endothelial cells as well as the pulp cells were revealed, suggesting the appearance of these genes upon mechanical stress induced by mastication and tongue pressure etc. On the other hand in the experiment group, Runx2 expression increased both in 30-minute and 3-hour teeth separation group. The expression became maximum at 24 hours. Then it gradually decreased and became similar level with the control group at 1-week after the wedge insertion. Similarly ALP expression increased after the wedge insertion and was maximum at 24 hours and then gradually decreased to the levels similar with the control group. These results suggest that when immunohistochemical expression of Runx2 as well as ALP was used as an index, no severe damage occur upon clinical application of wedge insertion. PMID:22027645

Potential drug-drug interactions and their risk factors in pediatric patients admitted to the emergency department of a tertiary care hospital in Mexico

PubMed Central

Reyes-López, Alfonso; Garduño-Espinosa, Juan; Muñoz-Hernández, Onofre

2018-01-01

Background Drug-drug interactions (DDIs) detected in a patient may not be clinically apparent (potential DDIs), and when they occur, they produce adverse drug reactions (ADRs), toxicity or loss of treatment efficacy. In pediatrics, there are only few publications assessing potential DDIs and their risk factors. There are no studies in children admitted to emergency departments (ED). The present study estimates the prevalence and describes the characteristics of potential DDIs in patients admitted to an ED from a tertiary care hospital in Mexico; in addition, potential DDI-associated risk factors are investigated. Methods A secondary analysis of data from 915 patients admitted to the ED of the Hospital Infantil de México “Federico Gómez” was conducted. The Medscape Drug Interaction Checker software was used to identify potential DDIs. The results are expressed as number of cases (%), means (95% CI) and medians (25-75th percentiles). Count data regressions for number of total and severity-stratified potential DDIs were performed adjusting for patient characteristics, number of administered drugs, days of stay, presence of ADRs and diagnoses. Results The prevalence of potential DDIs was 61%, with a median of 4 (2–8). A proportion of 0.2% of potential DDIs was “Contraindicated”, 7.5% were classified as “Serious”, 62.8% as “Significant” and 29.5% as “Minor”. Female gender, age, days of stay, number of administered drugs and diagnoses of Neoplasms (C00-D48), Congenital malformations (Q00-Q99), Diseases of the Blood, Blood-forming Organs and Immunity (D50-D89) and Diseases of the nervous system (G00-G99) were significantly associated with potential DDIs. Conclusion The prevalence of potential DDIs in the ED is high, and strategies should therefore be established to monitor patients’ safety during their stay, in addition to conducting investigations to estimate the real harm potential DDIs inflict on patients. PMID:29304072

Evaluation of the in vitro and in vivo metabolic pathway and cytochrome P450 inhibition/induction profile of Huperzine A.

PubMed

Lin, Ping-Ping; Li, Xue-Ning; Yuan, Fei; Chen, Wei-Li; Yang, Meng-Jie; Xu, Hong-Rong

2016-11-11

Huperzine A (HupA), one of the reversible and selective acetylcholinesterase inhibitors derived from Chinese herb Huperzia Serrata, possesses affirmative action of ameliorating cognitive dysfunction of Alzheimer's disease. Up to now, the effects of HupA on human cytochrome P450s (CYPs) have not been fully elucidated. The purpose of the present study was to clarify the metabolic pathway of HupA in vitro and in vivo, and to evaluate the CYPs inhibition/induction profile of HupA in vitro. The catalytic activity of CYP enzymes (CYP1A2, 2A6, 2C9, 2C19, 2D6, 2E1 and 3A4) was measured by the quantification of specific enzyme substrates using validated liquid chromatography-tandem mass spectrometry (LC/MS/MS) methods. The in vivo metabolic pathway evaluation was performed in an open, single-dose pharmacokinetic study of HupA in fourteen elderly subjects, with urine collecting at certain intervals. In human liver microsomes, HupA (10 ng/mL) was not metabolized within 90 min, and it showed negligible inhibition against these CYP isoforms within 0.2-100 ng/mL. In human liver hepatocytes, the activities of CYP1A2 and CYP3A4 were not significantly altered when incubated at 2 or 20 ng/mL of HupA. After oral administration of 0.1 mg HupA, the total proportion of HupA excreted through urine was relatively high, accounting to 35± 9% at the limited time period of 48 h. These results suggest that HupA is substantially excreted by kidney unchanged rather than metabolized by human liver, and is unlikely to cause clinically relevant drug-drug interaction (DDI) when co-administrated with drugs that are metabolized by CYP isoenzyme system. Copyright © 2016 Elsevier Inc. All rights reserved.

Drug Interactions Between Hepatoprotective Agents Ursodeoxycholic Acid or Glycyrrhizin and Ombitasvir/Paritaprevir/Ritonavir in Healthy Japanese Subjects.

PubMed

Zha, Jiuhong; Badri, Prajakta S; Ding, Bifeng; Uchiyama, Naotaka; Alves, Katia; Rodrigues, Lino; Redman, Rebecca; Dutta, Sandeep; Menon, Rajeev M

2015-11-01

The 2 direct-acting antiviral combination (2D) of ombitasvir and paritaprevir (coadministered with ritonavir) is being evaluated for the treatment of chronic hepatitis C virus infection in Japan. Ursodeoxycholic acid (UDCA) and glycyrrhizin (GCR) are hepatoprotective agents widely used in Japan. A drug-drug interaction (DDI) study was conducted to guide dosing recommendations for UDCA and GCR when coadministered with the 2D regimen. DDIs between the 2D regimen (ombitasvir/paritaprevir/ritonavir 25/150/100 mg orally once daily) and UDCA (50 mg orally 3 times daily) or GCR (80 mg intravenously once daily) were evaluated in a 2-arm, multiple-dose study in 24 Japanese healthy subjects under fed conditions. Pharmacokinetic and safety evaluations were performed when UDCA or GCR and the 2D regimen were administered alone and during coadministration. Exposures from coadministration of the 2D regimen plus UDCA or GCR versus the 2D regimen, UDCA, or GCR alone were compared using repeated-measures analyses of natural logarithms of the maximum plasma concentration (Cmax) and area under the curve (AUC). After coadministration of the 2D regimen and UDCA, steady-state exposures (Cmax and AUC) of ombitasvir, paritaprevir, and ritonavir showed a ≤9% change, and UDCA exposures showed a ≤20% change compared with administration alone. When the 2D regimen and GCR were coadministered, steady-state exposures of ombitasvir, paritaprevir, and ritonavir were not affected (≤9% change), GCR AUC increased by 49%, and GCR Cmax was unaffected (<1% change). No dose adjustment is needed for UDCA, GCR, or the 2D regimen when UDCA or GCR is coadministered with the 2D regimen in hepatitis C virus-infected patients under fed conditions. Clinical monitoring of patients using GCR is recommended due to an approximately 50% increase in GCR AUC when coadministered with the 2D regimen. Copyright © 2015 Elsevier HS Journals, Inc. All rights reserved.

Prediction of cancer proteins by integrating protein interaction, domain frequency, and domain interaction data using machine learning algorithms.

PubMed

Huang, Chien-Hung; Peng, Huai-Shun; Ng, Ka-Lok

2015-01-01

Many proteins are known to be associated with cancer diseases. It is quite often that their precise functional role in disease pathogenesis remains unclear. A strategy to gain a better understanding of the function of these proteins is to make use of a combination of different aspects of proteomics data types. In this study, we extended Aragues's method by employing the protein-protein interaction (PPI) data, domain-domain interaction (DDI) data, weighted domain frequency score (DFS), and cancer linker degree (CLD) data to predict cancer proteins. Performances were benchmarked based on three kinds of experiments as follows: (I) using individual algorithm, (II) combining algorithms, and (III) combining the same classification types of algorithms. When compared with Aragues's method, our proposed methods, that is, machine learning algorithm and voting with the majority, are significantly superior in all seven performance measures. We demonstrated the accuracy of the proposed method on two independent datasets. The best algorithm can achieve a hit ratio of 89.4% and 72.8% for lung cancer dataset and lung cancer microarray study, respectively. It is anticipated that the current research could help understand disease mechanisms and diagnosis.

Prediction of Cancer Proteins by Integrating Protein Interaction, Domain Frequency, and Domain Interaction Data Using Machine Learning Algorithms

PubMed Central

2015-01-01

Many proteins are known to be associated with cancer diseases. It is quite often that their precise functional role in disease pathogenesis remains unclear. A strategy to gain a better understanding of the function of these proteins is to make use of a combination of different aspects of proteomics data types. In this study, we extended Aragues's method by employing the protein-protein interaction (PPI) data, domain-domain interaction (DDI) data, weighted domain frequency score (DFS), and cancer linker degree (CLD) data to predict cancer proteins. Performances were benchmarked based on three kinds of experiments as follows: (I) using individual algorithm, (II) combining algorithms, and (III) combining the same classification types of algorithms. When compared with Aragues's method, our proposed methods, that is, machine learning algorithm and voting with the majority, are significantly superior in all seven performance measures. We demonstrated the accuracy of the proposed method on two independent datasets. The best algorithm can achieve a hit ratio of 89.4% and 72.8% for lung cancer dataset and lung cancer microarray study, respectively. It is anticipated that the current research could help understand disease mechanisms and diagnosis. PMID:25866773

Peripheral white blood cells profile of biodegradable metal implant in mice animal model

NASA Astrophysics Data System (ADS)

Paramitha, Devi; Noviana, Deni; Estuningsih, Sri; Ulum, Mokhamad Fakhrul; Nasution, Ahmad Kafrawi; Hermawan, Hendra

2015-09-01

Biocompatibility or safety of the medical device is considered important. It can be determined by blood profile examination. The aim of this study was to assess the biocompatibility of biodegradable metal implant through peripheral white blood cells (WBCs) profile approach. Forty eight male ddy mice were divided into four groups according to the materials implanted: iron wire (Fe), magnesium rod (Mg), stainless steel surgical wire (SS316L) and control with sham (K). Implants were inserted and attached onto the right femoral bone on latero-medial region. In this study, peripheral white blood cells and leukocyte differentiation were the parameters examined. The result showed that the WBCs value of all groups were decreased at the first day after implantation, increased at the 10th day and continued increasing at the 30th day of observation, except Mg group which has decreased. Neutrophil, as an inflammatory cells, was increased at the early weeks and decreased at the day-30 after surgery in all groups. Despite, these values during the observation were still within the normal range. As a conclus ion, biodegradable metal implants lead to an inflammatory reaction, with no adverse effect on WBC value found.

Peripheral white blood cells profile of biodegradable metal implant in mice animal model

DOE Office of Scientific and Technical Information (OSTI.GOV)

Paramitha, Devi; Noviana, Deni, E-mail: deni@ipb.ac.id; Estuningsih, Sri

Biocompatibility or safety of the medical device is considered important. It can be determined by blood profile examination. The aim of this study was to assess the biocompatibility of biodegradable metal implant through peripheral white blood cells (WBCs) profile approach. Forty eight male ddy mice were divided into four groups according to the materials implanted: iron wire (Fe), magnesium rod (Mg), stainless steel surgical wire (SS316L) and control with sham (K). Implants were inserted and attached onto the right femoral bone on latero-medial region. In this study, peripheral white blood cells and leukocyte differentiation were the parameters examined. The resultmore » showed that the WBCs value of all groups were decreased at the first day after implantation, increased at the 10th day and continued increasing at the 30th day of observation, except Mg group which has decreased. Neutrophil, as an inflammatory cells, was increased at the early weeks and decreased at the day-30 after surgery in all groups. Despite, these values during the observation were still within the normal range. As a conclus ion, biodegradable metal implants lead to an inflammatory reaction, with no adverse effect on WBC value found.« less

Drug-drug interactions involving antidepressants: focus on desvenlafaxine.

PubMed

Low, Yvette; Setia, Sajita; Lima, Graca

2018-01-01

Psychiatric and physical conditions often coexist, and there is robust evidence that associates the frequency of depression with single and multiple physical conditions. More than half of patients with depression may have at least one chronic physical condition. Therefore, antidepressants are often used in cotherapy with other medications for the management of both psychiatric and chronic physical illnesses. The risk of drug-drug interactions (DDIs) is augmented by complex polypharmacy regimens and extended periods of treatment required, of which possible outcomes range from tolerability issues to lack of efficacy and serious adverse events. Optimal patient outcomes may be achieved through drug selection with minimal potential for DDIs. Desvenlafaxine is a serotonin-norepinephrine reuptake inhibitor approved for the treatment of adults with major depressive disorder. Pharmacokinetic studies of desvenlafaxine have shown a simple metabolic profile unique among antidepressants. This review examines the DDI profiles of antidepressants, particularly desvenlafaxine, in relation to drugs of different therapeutic areas. The summary and comparison of information available is meant to help clinicians in making informed decisions when using desvenlafaxine in patients with depression and comorbid chronic conditions.

Drug–drug interactions involving antidepressants: focus on desvenlafaxine

PubMed Central

Low, Yvette; Setia, Sajita; Lima, Graca

2018-01-01

Psychiatric and physical conditions often coexist, and there is robust evidence that associates the frequency of depression with single and multiple physical conditions. More than half of patients with depression may have at least one chronic physical condition. Therefore, antidepressants are often used in cotherapy with other medications for the management of both psychiatric and chronic physical illnesses. The risk of drug–drug interactions (DDIs) is augmented by complex polypharmacy regimens and extended periods of treatment required, of which possible outcomes range from tolerability issues to lack of efficacy and serious adverse events. Optimal patient outcomes may be achieved through drug selection with minimal potential for DDIs. Desvenlafaxine is a serotonin–norepinephrine reuptake inhibitor approved for the treatment of adults with major depressive disorder. Pharmacokinetic studies of desvenlafaxine have shown a simple metabolic profile unique among antidepressants. This review examines the DDI profiles of antidepressants, particularly desvenlafaxine, in relation to drugs of different therapeutic areas. The summary and comparison of information available is meant to help clinicians in making informed decisions when using desvenlafaxine in patients with depression and comorbid chronic conditions. PMID:29497300

Fluoxetine and norfluoxetine mediated complex drug-drug interactions: in vitro to in vivo correlation of effects on CYP2D6, CYP2C19 and CYP3A4

PubMed Central

Sager, Jennifer E; Lutz, Justin D; Foti, Robert S; Davis, Connie; Kunze, Kent L; Isoherranen, Nina

2014-01-01

Fluoxetine and its circulating metabolite norfluoxetine present a complex multiple inhibitor system that causes reversible or time-dependent inhibition of CYP2D6, CYP3A4, and CYP2C19 in vitro. While significant inhibition of all three enzymes in vivo is predicted, midazolam and lovastatin AUCs were unaffected by two week dosing of fluoxetine whereas dextromethorphan AUC was increased by 27-fold and omeprazole AUC by 7.1-fold. This observed discrepancy between in vitro risk assessment and in vivo DDI profile was rationalized by time-varying dynamic pharmacokinetic models that incorporated circulating concentrations of fluoxetine and norfluoxetine enantiomers, mutual inhibitor-inhibitor interactions and CYP3A4 induction. The dynamic models predicted all DDIs with less than 2-fold error. This study demonstrates that complex drug-drug interactions that involve multiple mechanisms, pathways and inhibitors with their metabolites can be predicted and rationalized via characterization of all the inhibitory species in vitro. PMID:24569517

[Hyperkalemia-induced failure of pacemaker capture and sensing: a case report].

PubMed

Wang, Y P; Chen, B X; Su, K J; Sun, L J; Zhang, Y; Guo, L J; Gao, W

2014-12-18

Hyperkalemia may induce serious cardiac arrhythmia, with possible life-threatening effects. It may cause cardiac pacemaker (PMK) malfunctioning due to a reduction of the electronegativity of the resting myocardial potential. We report the case of a 71-year-old woman who had a previous history of chronic heart failure, chronic renal failure and DDI pacemaker. She was admitted for disturbance of consciousness. During hospitalization, she was observed for extreme hypotension, acute hyperkalemia, ventricular escape rhythm, associated with failure of pacemaker capture and sensing. She was treated with calcium chloride injection, followed by insulin/glucose and sodium bicarbonate infusions; the electrocardiogram recordings showed an correction of the PMK malfunctioning and serial improvement of the intraventricular conduction. This case supports that hyperkalemia should be closely monitored in the chronic heart failure patients combined with chronic renal failure.

CYP Suppression in Human Hepatocytes by Monomethyl Auristatin E, the Payload in Brentuximab Vedotin (Adcetris®), is Associated with Microtubule Disruption.

PubMed

Wolenski, Francis S; Xia, Cindy Q; Ma, Bingli; Han, Tae H; Shyu, Wen C; Balani, Suresh K

2018-06-01

Monomethyl auristatin E (MMAE), the toxin linked to CD30-specific monoclonal antibody of Adcetris ® (brentuximab vedotin), is a potent anti-microtubule agent. Brentuximab vedotin has been approved for the treatment of relapsed or refractory Hodgkin lymphoma and anaplastic large cell lymphoma. Cytochrome P450 (CYP) induction assessment of MMAE was conducted in human hepatocytes to assess DDI potentials and its translation to clinic. MMAE was incubated at 1-1000 nM with cultured primary human hepatocytes for 72 h, and CYP1A2, CYP2B6, and CYP3A4 mRNA expression was assessed by quantitative reverse transcription-polymerase chain reaction and CYP-specific probe substrate by liquid chromatography coupled with mass spectrometry, along with microtubule disruption by immunofluorescence staining using anti-β-tubulin antibody and imaging. MMAE up to 10 nM had no significant effect on CYP1A2, CYP2B6, and CYP3A4 mRNA expression and activity, whereas at higher concentrations of 100- and 1000-nM MMAE, the CYP mRNA expression and activity were diminished substantially. Further investigation showed that the degree of CYP suppression was paralleled by that of microtubule disruption by MMAE, as measured by increase in the number of β-tubulin-positive aggregates. At the clinical dose, the concentration of MMAE was 7 nM which did not show any significant CYP suppression or microtubule disruption in hepatocytes. MMAE was not a CYP inducer in human hepatocytes. However, it caused a concentration-dependent CYP mRNA suppression and activity. The CYP suppression was associated with microtubule disruption, supporting the reports that intact microtubule architecture is required for CYP regulations. The absence of CYP suppression and microtubule disruption in vitro at the clinical plasma concentrations of MMAE (< 10 nM) explains the lack of pharmacokinetic drug interaction between brentuximab vedotin and midazolam, a sensitive CYP3A substrate, reported in patients.

A study protocol for quantitative targeted absolute proteomics (QTAP) by LC-MS/MS: application for inter-strain differences in protein expression levels of transporters, receptors, claudin-5, and marker proteins at the blood–brain barrier in ddY, FVB, and C57BL/6J mice

PubMed Central

2013-01-01

Proteomics has opened a new horizon in biological sciences. Global proteomic analysis is a promising technology for the discovery of thousands of proteins, post-translational modifications, polymorphisms, and molecular interactions in a variety of biological systems. The activities and roles of the identified proteins must also be elucidated, but this is complicated by the inability of conventional proteomic methods to yield quantitative information for protein expression. Thus, a variety of biological systems remain “black boxes”. Quantitative targeted absolute proteomics (QTAP) enables the determination of absolute expression levels (mol) of any target protein, including low-abundance functional proteins, such as transporters and receptors. Therefore, QTAP will be useful for understanding the activities and roles of individual proteins and their differences, including normal/disease, human/animal, or in vitro/in vivo. Here, we describe the study protocols and precautions for QTAP experiments including in silico target peptide selection, determination of peptide concentration by amino acid analysis, setup of selected/multiple reaction monitoring (SRM/MRM) analysis in liquid chromatography–tandem mass spectrometry, preparation of protein samples (brain capillaries and plasma membrane fractions) followed by the preparation of peptide samples, simultaneous absolute quantification of target proteins by SRM/MRM analysis, data analysis, and troubleshooting. An application of QTAP in biological sciences was introduced that utilizes data from inter-strain differences in the protein expression levels of transporters, receptors, tight junction proteins and marker proteins at the blood–brain barrier in ddY, FVB, and C57BL/6J mice. Among 18 molecules, 13 (abcb1a/mdr1a/P-gp, abcc4/mrp4, abcg2/bcrp, slc2a1/glut1, slc7a5/lat1, slc16a1/mct1, slc22a8/oat3, insr, lrp1, tfr1, claudin-5, Na+/K+-ATPase, and γ-gtp) were detected in the isolated brain capillaries, and their protein expression levels were within a range of 0.637-101 fmol/μg protein. The largest difference in the levels between the three strains was 2.2-fold for 13 molecules, although bcrp and mct1 displayed statistically significant differences between C57BL/6J and the other strain(s). Highly sensitive simultaneous absolute quantification achieved by QTAP will increase the usefulness of proteomics in biological sciences and is expected to advance the new research field of pharmacoproteomics (PPx). PMID:23758935

Analysis of immune responses in genital tracts of mice immunised with purified ribosomal fractions of Neisseria gonorrhoeae.

PubMed Central

Kita, E; Kashiba, S

1984-01-01

Immunisation of ddY mice with the purified ribosomal fraction of Neisseria gonorrhoeae was found to protect against intravaginal challenge with homologous organisms. This protection correlated with the presence of bactericidal antibody to purified ribosomal fraction in serum as well as in vaginal secretions. Analysis of the vaginal fluids from control mice and those immunised with purified ribosomal fraction showed that the enhanced elimination of gonococci in immune mice might be because of an early response of leucocytes generated by the reaction mediated by antibody and complement. Absorption studies showed that there was at least one major protective antigen in purified ribosomal fraction, other than cell surface substances such as lipopolysaccharide, outer membrane proteins, and pili. Bactericidal assays mediated by antibody and complement showed that matched samples of serum and vaginal fluid from immune mice had comparable gonococcidal activity, which was augmented by the effect of progesterone. Although delayed hypersensitivity was produced in immune mice that were resistant to N gonorrhoeae, the exact role of cellular immunity could not be clarified in this study. These results suggest that antibody to purified ribosomal fraction plays a major part in protection against gonococcal infection in the genital tract, and that such protection may entail both cellular immunity and hormonal changes. PMID:6430462

Anti-cholesterol activity in vivo test of multifunction herbs extract in the water using in vivo method in mice (Mus musculus L.) DDY-strain

NASA Astrophysics Data System (ADS)

Tristantini, Dewi; Christina, Diana

2018-02-01

Atherosclerosis is the hardening of the arteries due to cholesterol accumulation in the blood vessels. The occurrence of cardiovascular disease can be reduced by lowering cholesterol levels in the blood. Nevertheless, using some pharmaceutical synthetic medicine for lowering the cholesterol has several side effects that dangerous for human body. There are 3 plants, tanjung leaf (Mimusops elengi L.), star fruit leaf (Averrhoa carambola L.), and curcuma (Curcuma xanthorrhiza L.), which are combined empirically believed would serve as multifunction herbs. Tanjung leaf has been known to have antioxidant, anti-cholesterol, and anti-platelet activity, also star fruit leaf have anti-hyperglycemia activity. Furthermore, curcuma has been known as a hepatoprotection agent. In this study, the combination of all three simplicias were used as anti-cholesterol. Anti-cholesterol activity test by in vivo method using mice (Mus muculus L.) result in decreased cholesterol as much as 47% for 250 mL human dosage in 7 days. This performance equals to 73% of simvastatin activity in decreased cholesterol. In this study, we can conclude the multifunction herbs that were combination of tanjung (M. elengi) leaf, star fruit leaf (Averrhoa carambola L.), and curcuma (Curcuma xanthorrhiza L.) extract can be used as cholesterol decreasing medicine.

Investigating Transporter‐Mediated Drug‐Drug Interactions Using a Physiologically Based Pharmacokinetic Model of Rosuvastatin

PubMed Central

Wang, Q; Leil, T

2017-01-01

Rosuvastatin is a frequently used probe in transporter‐mediated drug‐drug interaction (DDI) studies. This report describes the development of a physiologically based pharmacokinetic (PBPK) model of rosuvastatin for prediction of pharmacokinetic (PK) DDIs. The rosuvastatin model predicted the observed single (i.v. and oral) and multiple dose PK profiles, as well as the impact of coadministration with transporter inhibitors. The predicted effects of rifampin and cyclosporine (6.58‐fold and 5.07‐fold increase in rosuvastatin area under the curve (AUC), respectively) were mediated primarily via inhibition of hepatic organic anion‐transporting polypeptide (OATP)1B1 (Inhibition constant (Ki) ∼1.1 and 0.014 µM, respectively) and OATP1B3 (Ki ∼0.3 and 0.007 µM, respectively), with cyclosporine also inhibiting intestinal breast cancer resistance protein (BCRP; Ki ∼0.07 µM). The predicted effects of gemfibrozil and its metabolite were moderate (1.88‐fold increase in rosuvastatin AUC) and mediated primarily via inhibition of hepatic OATP1B1 and renal organic cation transporter 3. This model of rosuvastatin will be useful in prospectively predicting transporter‐mediated DDIs with novel pharmaceutical agents in development. PMID:28296193

In Vivo antiplatelet activity aggregation assay of bromelain fractionate by ethanol from extract pineapple core (Ananas comosus [l.] merr.)

NASA Astrophysics Data System (ADS)

Musfiroh, F. F.; Setiasih, S.; Handayani, S.; Hudiyono, S.; Ilyas, N. M.

2018-01-01

Processed fruit from pineapple is one of largest commodities tropical fruit production in Indonesia and will bring the waste from the skin and core. This study aims to isolate bromelain from the pineapple core (Ananas comusus) are purified by fractionation using ethanol and continued by activity test as an antiplatelets agent by in vivo method using white mice male ddy type with acetosal as positive control. Fractionation of crude enzyme bromelain with ethanol produces highest specific activity on ethanol 30-60% fraction (fraction 2) 3.107 Unit/mg and the protein content 61.25 mg with the degree of purity of 155 times compared to crude enzyme. Antiplatelet aggregation tests from in vivo method shows that faction of bromelain with doses 70 μg/KgBW, 140 μg/KgBW, and 210 μg/KgBW can increase a meaningful bleeding time. The highest percentage of increase shown by the isolate at a dose of 210 μg/KgBW in the amount of 515.10 ± 182.23%, when compared to aspirin (231.20 ± 140.66), the value is relatively higher.

Astaxanthin Protects Against Retinal Damage: Evidence from In Vivo and In Vitro Retinal Ischemia and Reperfusion Models.

PubMed

Otsuka, Tomohiro; Shimazawa, Masamitsu; Inoue, Yuki; Nakano, Yusuke; Ojino, Kazuki; Izawa, Hiroshi; Tsuruma, Kazuhiro; Ishibashi, Takashi; Hara, Hideaki

2016-11-01

Astaxanthin exhibits various pharmacological activities, including anti-oxidative, anti-tumor, and anti-inflammatory effects, and is thought to exert a neuroprotective effect via these mechanisms. The purpose of this study was to investigate the protective effects of astaxanthin on neuronal cell death using a retinal ischemia/reperfusion model. In vivo, retinal ischemia was induced by 5 h unilateral ligation of the pterygopalatine artery (PPA) and the external carotid artery (ECA) in ddY mice. Astaxanthin (100 mg/kg) was administered orally 1 h before induction of ischemia, immediately after reperfusion, at 6 or 12 h after reperfusion, and twice daily for the following 4 days. Histological analysis and an electroretinogram (ERG) were performed 5 days after ischemia/reperfusion. In vitro, cell death was induced in the RGC-5 (retinal precursor cells) by oxygen-glucose deprivation (OGD), and the rates of cell death and production of intracellular reactive oxygen species (ROS) were measured using nuclear staining and a ROS reactive reagent, CM-H 2 DCFDA. Histological studies revealed that astaxanthin significantly reduced retinal ischemic damage and ERG reduction. In in vitro studies, astaxanthin inhibited cell death and ROS production in a concentration-dependent manner. Collectively, these results indicate that astaxanthin inhibits ischemia-induced retinal cell death via its antioxidant effect. Hence, astaxanthin might be effective in treating retinal ischemic pathologies.

Intake of Phthalate-tainted Foods and Serum Thyroid Hormones in Taiwanese Children and Adolescents

NASA Astrophysics Data System (ADS)

Tsai, Hui-Ju; Wu, Chia-Fang; Tsai, Yi-Chun; Huang, Po-Chin; Chen, Mei-Lien; Wang, Shu-Li; Chen, Bai-Hsiun; Chen, Chu-Chih; Wu, Wen-Chiu; Hsu, Pi-Shan; Hsiung, Chao A.; Wu, Ming-Tsang

2016-07-01

On April-May, 2011, phthalates, mainly Di-(2-ethylhexyl) phthalate (DEHP), were deliberately added to a variety of foodstuff as a substitute emulsifier in Taiwan. This study investigated the relationship between DEHP-tainted foodstuffs exposure and thyroid function in possibly affected children and adolescents. Two hundred fifty participants <18 years possibly exposed to DEHP were enrolled in this study between August 2012 and January 2013. Questionnaires were used to collect details on their past exposure to DEHP-tainted food items. Blood and urine samples were collected for biochemical workups to measure current exposure derived from three urinary DEHP metabolites using a creatinine excretion-based model. More than half of 250 participants were estimated to be exposed to DEHP-tainted foods found to exceed the recommend tolerable daily intake of DEHP established by the European Food Safety Authority (<50 μg/kg/day). The median daily DEHP intake (DDI) among those 250 participants was 46.52 μg/kg/day after multiple imputation. This value was ~10-fold higher than the current median DEHP intake (4.46 μg/kg/day, n = 240). Neither past nor current DEHP exposure intensity was significantly associated with serum thyroid profiles. Future studies may want to follow the long-term health effects of this food scandal in affected children and adolescents.

Characteristics of a group of nonnucleoside reverse transcriptase inhibitors with structural diversity and potent anti-human immunodeficiency virus activity.

PubMed

Yang, S S; Fliakas-Boltz, V; Bader, J P; Buckheit, R W

1995-10-01

Current thrust in controlling the Acquired Immune Deficiency Syndrome (AIDS) focuses on antiviral drug development targeting the infection and replication of the human immunodeficiency virus (HIV), the causative agent of AIDS. To date, treatment of AIDS has relied on nucleoside reverse transcriptase inhibitors such as AZT, ddI, and ddC, which eventually become ineffective upon the emergence of resistant mutants bearing specific nucleotide substitutions. The Anti-AIDS Drug Screening Program of the NCI conducts and coordinates a high-capacity semi-robotic in vitro screening of synthetic or natural compounds submitted by academic, research and pharmaceutical institutions world-wide. About 10,000 synthetic compounds are screened annually for anti-HIV activity. Confirmed active agents are subjected to in-depth studies on range and mechanism of action. Emerging from this intense screening activity were a number of potentially promising categories of nonnucleoside reverse transcriptase inhibitors (NNRTI) with structural diversity but strong and reproducible anti-HIV activity. Over 2500 active compounds were evaluated for their inhibitory activity against a panel of both laboratory and clinical virus isolates in the appropriate established cell line or fresh human peripheral blood leukocyte and macrophage preparations. Out of these, 40 agents could be placed structurally in nine categories with an additional 16 unique compounds that share the characteristics of NNRTI. These NNRTIs were shown to inhibit reverse transcriptase enzymatically using homopolymeric or ribosomal RNA as templates. NNRTIs demonstrated similarity in their inhibitory pattern against the HIV-1 laboratory strains IIIB and RF, and an AZT-resistant strain; all were inactive against HIV-2. These compounds were further tested against NNRTI-resistant HIV-1 isolates. NNRTI-resistant HIV-1 isolates were selected and characterized with respect to the change(s) in the viral reverse transcriptase nucleotide sequence. Also, differential cross-resistance or sensitivity patterns to NNRTIs were studied in detail among NNRTI-resistant mutants. When tested in combination with AZT, all of the NNRTI's uniformly exhibited synergistic inhibition of HIV-1, suggesting that combination antiviral therapy of NNRTIs with AZT may be therapeutically promising for AIDS treatment.

Pretreatment with broad-spectrum antibiotics alters the pharmacokinetics of major constituents of Shaoyao-Gancao decoction in rats after oral administration.

PubMed

Liu, Meng; Yuan, Jie; Hu, Wen-Juan; Ke, Chang-Qiang; Zhang, Yi-Fan; Ye, Yang; Zhong, Da-Fang; Zhao, Guang-Rong; Yao, Sheng; Liu, Jia

2018-05-17

The influence of broad-spectrum antibiotics on the pharmacokinetics and biotransformation of major constituents of Shaoyao-Gancao decoction (SGD) in rats was investigated. The pharmacokinetic behaviors of paeoniflorin (PF), albiflorin (AF), liquiritin (LT), isoliquiritin (ILT), liquiritin apioside (LA), isoliquiritin apioside (ILA), and glycyrrhizic acid (GL), seven major constituents of SGD, as well as glycyrrhetinic acid (GA), a major metabolite of GL, were analyzed. A 1-week pretreatment with broad-spectrum antibiotics (ampicillin, metronidazole, neomycin, 1 g L -1 ; and vancomycin, 0.5 g L -1 ) via drinking water reduced plasma exposure of the major constituents. The AUC 0-24 h of PF and LT was significantly decreased by 28.7% and 33.8% (P < 0.05 and P < 0.005), respectively. Although the differences were not statistically significant, the AUC 0-24 h of AF, ILT, LA, ILA, and GL was decreased by 31.4%, 50.9%, 16.9%, 44.1%, and 37.0%, respectively, compared with the control group. In addition, the plasma GA exposure in the antibiotic-pretreated group was significantly lower (P < 0.005) than the control group. The in vitro stability of the major constituents of SGD in the rat intestinal contents with or without broad-spectrum antibiotics was also investigated. The major constituents were comparatively stable in the rat duodenum contents, and the biotransformation of GL mainly occurred in the rat colon contents. In summary, broad-spectrum antibiotics suppressed the absorption of the major constituents of SGD and significantly inhibited the biotransformation of GL to GA by suppressing the colon microbiota. The results indicated a potential clinical drug-drug interaction (DDI) when SGD was administered with broad-spectrum antibiotics.

The clinical significance of drug-drug interactions in the era of direct-acting anti-viral agents against chronic hepatitis C.

PubMed

Maasoumy, B; Port, K; Calle Serrano, B; Markova, A A; Sollik, L; Manns, M P; Cornberg, M; Wedemeyer, H

2013-12-01

Drug-drug interactions (DDIs) in the treatment of chronic hepatitis C infection became a potential challenge with the introduction of direct-acting anti-virals (DAAs). Both currently approved DAAs, the protease inhibitors (PIs) telaprevir (TVR) and boceprevir (BOC), are substrates and inhibitors of P-glycoprotein and the cytochrome P450 3A4, which are regularly involved in DDIs. To analyse the risk for DDIs in patients with chronic HCV genotype 1 infection considered for PI treatment at a tertiary referral centre. The first 115 consecutive patients selected for a PI therapy at Hannover Medical School were included. All changes to co-medication before and during PI treatment were documented. Drugs were checked for DDIs with TVR and BOC using DDI websites and the respective prescribing information. Out-patient medication contained 116 different drugs. Median number of drugs/patient was 2 (range 0-11). The risk for DDIs was substantial for 38% of the drugs affecting 49% of patients. Only 4% of the drugs were strictly contraindicated. DDIs between a PI and drugs newly prescribed during anti-viral therapy were considerable in 42% of the patients. Suspected DDIs were managed by dose adjustments and discontinuation of co-medication in 7% and 21% of the patients respectively. Many patients with chronic HCV genotype 1 infection are affected by potential DDIs if treated with a protease inhibitor, but only in a minority of cases co-medication is strictly incompatible. Overall, the challenge of DDIs is time-consuming, but well manageable by a careful review of the patient's drug chart and monitoring during treatment. © 2013 John Wiley & Sons Ltd.

Sodium transport through the cerebral sodium-glucose transporter exacerbates neuron damage during cerebral ischaemia.

PubMed

Yamazaki, Yui; Harada, Shinichi; Wada, Tetsuyuki; Yoshida, Shigeru; Tokuyama, Shogo

2016-07-01

We recently demonstrated that the cerebral sodium-glucose transporter (SGLT) is involved in postischaemic hyperglycaemia-induced exacerbation of cerebral ischaemia. However, the associated SGLT-mediated mechanisms remain unclear. Thus, we examined the involvement of cerebral SGLT-induced excessive sodium ion influx in the development of cerebral ischaemic neuronal damage. [Na+]i was estimated according to sodium-binding benzofuran isophthalate fluorescence. In the in vitro study, primary cortical neurons were prepared from fetuses of ddY mice. Primary cortical neurons were cultured for 5 days before each treatment with reagents, and these survival rates were assessed using biochemical assays. In in vivo study, a mouse model of focal ischaemia was generated using middle cerebral artery occlusion (MCAO). In these experiments, treatment with high concentrations of glucose induced increment in [Na+]i, and this phenomenon was suppressed by the SGLT-specific inhibitor phlorizin. SGLT-specific sodium ion influx was induced using a-methyl-D-glucopyranoside (a-MG) treatments, which led to significant concentration-dependent declines in neuronal survival rates and exacerbated hydrogen peroxide-induced neuronal cell death. Moreover, phlorizin ameliorated these effects. Finally, intracerebroventricular administration of a-MG exacerbated the development of neuronal damage induced by MCAO, and these effects were ameliorated by the administration of phlorizin. Hence, excessive influx of sodium ions into neuronal cells through cerebral SGLT may exacerbate the development of cerebral ischaemic neuronal damage. © 2016 Royal Pharmaceutical Society.

Synthesis and characterization of polyurethane/bentonite nanoclay based nanocomposites using different diisocyanates: relation between mechanical and thermal properties

NASA Astrophysics Data System (ADS)

Bocchio, Javier; Wittemberg, Víctor; Quagliano, Javier

2017-05-01

Polyurethanes (PUs) and polyurethane nanocomposites (PUNC) with bentonite nanoclay were prepared by the reaction of toluene-2,4-diisocyanate (TDI), dimeryl diisocyanate (DDI) and isophorone diisocyanate (IPDI) with two different polymers: hydroxyl terminated polybutadiene (HTPB) and polytetramethylene ether glycol (PTMEG), and the chains were further extended with 1,4-butanediol (1,4-BDO) to get final PUs and PUNCs. PUNCs were prepared by dispersing within the polymers a commercial and a synthesized bentonite nanoclay by mechanical dispersion. Mechanical properties showed that the addition of a small amount of nanoclay resulted in a significant increase in tensile strength and reduction in elongation at break (maximum increase of 2.3 and 5-times reduction, respectively, for a HTPB-TDI-BDO PUNCs). Thermal analysis revealed that the addition of nanoclays improved the thermal stability and increased decomposition temperature of PUNCs. We concluded that there is a positive correlation between mechanical and thermal properties as a result of nanoclay addition.

Morphometric characteristics and COI haplotype diversity of Arctodiaptomus spinosus (Copedoda) populations in soda pans in Hungary.

PubMed

Forró, László; Nédli, Judit; Csata, Enikő; Krízsik, Virág; Balogh, Csilla; G-Tóth, László

2017-09-01

Arctodiaptomus spinosus (Daday, 1891) is a characteristic species of the soda pan zooplankton in the Great Hungarian Plain. The biogeographical distribution of the species is interesting, since its range expands from the Pannonian Biogeographic region to the other side of the Carpathians, occurring in saline lakes in Eastern Anatolia, Armenia, Iran and in temporary waters in Ukraine. Our investigations focused on the morphometric characteristics and the COI haplotype diversity of four Hungarian populations in the Kiskunság area. We detected substantial morphological differences between the Böddi-szék population and the rest of the sampling sites, however considerable differences were not observable in the COI haplotypes in the populations. The 20 animals investigated for COI haplotypes belonged to the same haplotype network. Tajima's D indicated departures from the neutral Wright - Fisher population model and suggested population expansion. The genetic composition of Arctodiaptomus spinosus populations in the Kiskunság area is rather uniform.

Umbilical cord prolapse in primary midwifery care in the Netherlands; a case series.

PubMed

Smit, Marrit; Zwanenburg, Fleur; van der Wolk, Sabine; Middeldorp, Johanna; Havenith, Barbara; van Roosmalen, Jos

2014-06-01

We aimed to gain insight into umbilical cord prolapse (UCP) reported by primary care midwives in the Netherlands. Cases of UCP were reported by midwives who participated in a postgraduate training programme developed for community-based midwives. Cases were analysed using midwifery charts, ambulance report forms and discharge letters. Procedures to alleviate cord pressure, ambulance timing, mode of birth and neonatal outcomes were inventoried. Diagnosis to delivery interval (DDI) and risk factors were identified. Eight cases of UCP in primary midwifery care were reported of which six occurred at home. Risk factors such as malpresentation (breech) and/or unengaged presenting part were found in four cases, two (unengaged fetal head) were known to the midwife prior to birth. Retrograde bladder filling (2/8), manual elevation of the fetal head (7/8) and Trendelenburg position (1/8) were applied. One infant died of severe birth asphyxia; the other infants recovered and were discharged in good condition.

Drug induced acute pancreatitis: incidence and severity.

PubMed Central

Lankisch, P G; Dröge, M; Gottesleben, F

1995-01-01

To determine the incidence and severity of drug induced acute pancreatitis, data from 45 German centres of gastroenterology were evaluated. Among 1613 patients treated for acute pancreatitis in 1993, drug induced acute pancreatitis was diagnosed in 22 patients (incidence 1.4%). Drugs held responsible were azathioprine, mesalazine/sulfasalazine, 2',3'-dideoxyinosine (ddI), oestrogens, frusemide, hydrochlorothiazide, and rifampicin. Pancreatic necrosis not exceeding 33% of the organ was found on ultrasonography or computed tomography, or both, in three patients (14%). Pancreatic pseudocysts did not occur. A decrease of arterial PO2 reflecting respiratory insufficiency, and an increase of serum creatinine, reflecting renal insufficiency as complications of acute pancreatitis were seen in two (9%) and four (18%) patients, respectively. Artificial ventilation was not needed, and dialysis was necessary in only one (5%) case. Two patients (9%) died of AIDS and tuberculosis, respectively; pancreatitis did not seem to have contributed materially to their death. In conclusion, drugs rarely cause acute pancreatitis, and drug induced acute pancreatitis usually runs a benign course. PMID:7489946

Recovering Protein-Protein and Domain-Domain Interactions from Aggregation of IP-MS Proteomics of Coregulator Complexes

PubMed Central

Mazloom, Amin R.; Dannenfelser, Ruth; Clark, Neil R.; Grigoryan, Arsen V.; Linder, Kathryn M.; Cardozo, Timothy J.; Bond, Julia C.; Boran, Aislyn D. W.; Iyengar, Ravi; Malovannaya, Anna; Lanz, Rainer B.; Ma'ayan, Avi

2011-01-01

Coregulator proteins (CoRegs) are part of multi-protein complexes that transiently assemble with transcription factors and chromatin modifiers to regulate gene expression. In this study we analyzed data from 3,290 immuno-precipitations (IP) followed by mass spectrometry (MS) applied to human cell lines aimed at identifying CoRegs complexes. Using the semi-quantitative spectral counts, we scored binary protein-protein and domain-domain associations with several equations. Unlike previous applications, our methods scored prey-prey protein-protein interactions regardless of the baits used. We also predicted domain-domain interactions underlying predicted protein-protein interactions. The quality of predicted protein-protein and domain-domain interactions was evaluated using known binary interactions from the literature, whereas one protein-protein interaction, between STRN and CTTNBP2NL, was validated experimentally; and one domain-domain interaction, between the HEAT domain of PPP2R1A and the Pkinase domain of STK25, was validated using molecular docking simulations. The scoring schemes presented here recovered known, and predicted many new, complexes, protein-protein, and domain-domain interactions. The networks that resulted from the predictions are provided as a web-based interactive application at http://maayanlab.net/HT-IP-MS-2-PPI-DDI/. PMID:22219718

Toxicology studies of primycin-sulphate using a three-dimensional (3D) in vitro human liver aggregate model.

PubMed

Pénzes, Ágota; Mahmud Abdelwahab, Elhusseiny Mohamed; Rapp, Judit; Péteri, Zsanett A; Bovári-Biri, Judit; Fekete, Csaba; Miskei, György; Kvell, Krisztián; Pongrácz, Judit E

2017-11-05

Primycin-sulphate is a highly effective compound against Gram (G) positive bacteria. It has a potentially synergistic effect with vancomycin and statins which makes primycin-sulphate a potentially very effective preparation. Primycin-sulphate is currently used exclusively in topical preparations. In vitro animal hepatocyte and neuromuscular junction studies (in mice, rats, snakes, frogs) as well as in in vitro human red blood cell experiments were used to test toxicity. During these studies, the use of primycin-sulphate resulted in reduced cellular membrane integrity and modified ion channel activity. Additionally, parenteral administration of primycin-sulphate to mice, dogs, cats, rabbits and guinea pigs indicated high level of acute toxicity. The objective of this study was to reveal the cytotoxic and gene expression modifying effects of primycin-sulphate in a human system using an in vitro, three dimensional (3D) human hepatic model system. Within the 3D model, primycin-sulphate presented no acute cytotoxicity at concentrations 1μg/ml and below. However, even at low concentrations, primycin-sulphate affected gene expressions by up-regulating inflammatory cytokines (e.g., IL6), chemokines (e.g., CXCL5) and by down-regulating molecules of the lipid metabolism (e.g., peroxisome proliferator receptor (PPAR) alpha, gamma, etc). Down-regulation of PPAR alpha cannot just disrupt lipid production but can also affect cytochrome P450 metabolic enzyme (CYP) 3A4 expression, highlighting the need for extensive drug-drug interaction (DDI) studies before human oral or parenteral preparations can be developed. Copyright © 2017 Elsevier B.V. All rights reserved.

Telmisartan prevented cognitive decline partly due to PPAR-{gamma} activation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mogi, Masaki; Li Jianmei; Tsukuda, Kana

Telmisartan is a unique angiotensin receptor blocker (ARB) and partial agonist of peroxisome proliferator-activated receptor (PPAR)-{gamma}. Here, we investigated the preventive effect of telmisartan on cognitive decline in Alzheimer disease. In ddY mice, intracerebroventricular injection of A{beta} 1-40 significantly attenuated their cognitive function evaluated by shuttle avoidance test. Pretreatment with a non-hypotensive dose of telmisartan significantly inhibited such cognitive decline. Interestingly, co-treatment with GW9662, a PPAR-{gamma} antagonist, partially inhibited this improvement of cognitive decline. Another ARB, losartan, which has less PPAR-{gamma} agonistic effect, also inhibited A{beta}-injection-induced cognitive decline; however the effect was smaller than that of telmisartan and was notmore » affected by GW9662. Immunohistochemical staining for A{beta} showed the reduced A{beta} deposition in telmisartan-treated mice. However, this reduction was not observed in mice co-administered GW9662. These findings suggest that ARB has a preventive effect on cognitive impairment in Alzheimer disease, and telmisartan, with PPAR-{gamma} activation, could exert a stronger effect.« less

A novel Alaska pollack-derived peptide, which increases glucose uptake in skeletal muscle cells, lowers the blood glucose level in diabetic mice.

PubMed

Ayabe, Tatsuhiro; Mizushige, Takafumi; Ota, Wakana; Kawabata, Fuminori; Hayamizu, Kohsuke; Han, Li; Tsuji, Tomoko; Kanamoto, Ryuhei; Ohinata, Kousaku

2015-08-01

We found that the tryptic digest of Alaska pollack protein exhibits a glucose-lowering effect in KK-Ay mice, a type II diabetic model. We then searched for glucose-lowering peptides in the digest. Ala-Asn-Gly-Glu-Val-Ala-Gln-Trp-Arg (ANGEVAQWR) was identified from a peak of the HPLC fraction selected based on the glucose-lowering activity in an insulin resistance test using ddY mice. ANGEVAQWR (3 mg kg(-1)) decreased the blood glucose level after intraperitoneal administration. Among its fragment peptides, the C-terminal tripeptide, Gln-Trp-Arg (QWR, 1 mg kg(-1)), lowered the blood glucose level, suggesting that the C-terminal is critical for glucose-lowering activity. QWR also enhanced glucose uptake into C2C12, a mouse skeletal muscle cell line. QWR did not induce the phosphorylation of serine/threonine protein kinase B (Akt) and adenosine monophosphate-activated protein kinase (AMPK). We also demonstrated that QWR lowered the blood glucose level in NSY and KK-Ay, type II diabetic models.

Prebiotic properties of epilactose.

PubMed

Watanabe, J; Nishimukai, M; Taguchi, H; Senoura, T; Hamada, S; Matsui, H; Yamamoto, T; Wasaki, J; Hara, H; Ito, S

2008-12-01

We recently reported that cellobiose 2-epimerase from Ruminococcus albus effectively converted lactose to epilactose. In this study, we examined the biological effects of epilactose on intestinal microbiota, bile acid metabolism, and postadministrative plasma glucose by animal tests. Dietary supplementation with epilactose or fructooligosaccharide (4.5% each) increased cecal wall weight and cecal contents and decreased the pH of the cecal contents in Wistar-ST rats. The number of total anaerobes tended to be greater in rats fed epilactose and fructooligosaccharide than in those fed the control diet. Lactobacilli and bifidobacteria were more numerous in rats fed epilactose and fructooligosaccharide diets than in those fed the control diet. Analysis of clone libraries of 16S rRNA suggests that supplementation with epilactose did not induce the proliferation of harmful bacteria belonging to classes Clostridia or Bacteroidetes. Epilactose, as well as fructooligosaccharide, inhibited the conversion of primary bile acids to secondary bile acids, which are suggested to be promoters of colon cancer. In addition, oral administration of epilactose did not elevate the plasma glucose concentration in ddY mice. These results clearly indicate that epilactose is a promising prebiotic. We also showed that cellobiose 2-epimerase converted lactose in cow milk and a spray-dried ultrafiltrate of cheese whey to epilactose. Cellobiose 2-epimerase may increase the value of dairy products by changing lactose to epilactose possessing prebiotic properties.

Fused heterocycles bearing bridgehead nitrogen as potent HIV-1 NNRTIs. Part 3: optimization of [1,2,4]triazolo[1,5-a]pyrimidine core via structure-based and physicochemical property-driven approaches.

PubMed

Huang, Boshi; Li, Cuicui; Chen, Wenmin; Liu, Tao; Yu, Mingyan; Fu, Lu; Sun, Yueyue; Liu, Huiqing; De Clercq, Erik; Pannecouque, Christophe; Balzarini, Jan; Zhan, Peng; Liu, Xinyong

2015-03-06

In our arduous efforts to develop new potent HIV-1 non-nucleoside reverse transcriptase (RT) inhibitors (NNRTIs), novel piperidine-linked [1,2,4]triazolo[1,5-a]pyrimidine derivatives were designed, synthesized and evaluated for their antiviral activities in MT-4 cell cultures. Biological results showed that all of the title compounds displayed moderate to excellent activities against wild-type (wt) HIV-1 strain (IIIB) with EC50 values ranging from 8.1 nM to 2284 nM in a cell-based assay. Among them, the most promising analog 7d possessed an EC50 value of 8.1 nM against wt HIV-1, which was much more potent than the reference drugs DDI, 3 TC, NVP and DLV. Additionally, 7d demonstrated weak activity against the double mutant HIV-1 strain (K103N + Y181C), and was more efficient than NVP in a RT inhibition assay. Besides, some measured and calculated physicochemical properties of 7d, like log P and water solubility, as well as the structure-activity relationships (SARs) analysis have been discussed in detail. Furthermore, the binding mode of the active compound 7d was rationalized by molecular simulation studies. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Effects of Adjuvant Analgesics on Cerebral Ischemia-Induced Mechanical Allodynia.

PubMed

Matsuura, Wataru; Harada, Shinichi; Tokuyama, Shogo

2016-01-01

Central post-stroke pain (CPSP), a potential sequela of stroke, is classified as neuropathic pain. Although we recently established a CPSP-like model in mice, the effects of adjuvant analgesics as therapeutic drugs for neuropathic pain in this model are unknown. Hence, the aim of the present study was to assess the usefulness of our model by evaluating the effects of adjuvant analgesics used for treating neuropathic pain in this mouse model of CPSP. Male ddY mice were subjected to 30 min of bilateral carotid artery occlusion (BCAO). The development of hind paw mechanical allodynia was measured after BCAO using the von Frey test. The mechanical allodynia was significantly increased on day 3 after BCAO compared with that during the pre-BCAO assessment. BCAO-induced mechanical allodynia was significantly decreased by intraperitoneal injections of imipramine (a tricyclic antidepressant), mexiletine (an antiarrhythmic), gabapentin (an antiepileptic), or a subcutaneous injection of morphine (an opioid receptor agonist) compared with that following vehicle treatment in BCAO-mice. By contrast, milnacipran (a serotonin and norepinephrine reuptake inhibitor), paroxetine (selective serotonin reuptake inhibitor), carbamazepine (antiepileptic), and indomethacin (nonsteroidal anti-inflammatory drug) did not affect the BCAO-induced mechanical allodynia. Our results show that BCAO in mice may be useful as an animal model of CPSP. In addition, BCAO-induced mechanical allodynia may be suppressed by some adjuvant analgesics used to treat neuropathic pain.

Influence of different proton pump inhibitors on the pharmacokinetics of voriconazole.

PubMed

Qi, Fang; Zhu, Liqin; Li, Na; Ge, Tingyue; Xu, Gaoqi; Liao, Shasha

2017-04-01

This study aimed to determine the influence of proton pump inhibitors (PPIs) on the pharmacokinetics of voriconazole and to characterise potential drug-drug interactions (DDIs) between voriconazole and various PPIs (omeprazole, esomeprazole, lansoprazole and rabeprazole). Using adjusted physicochemical data and the pharmacokinetic (PK) parameters of voriconazole and PPIs, physiologically based pharmacokinetic (PBPK) models were built and were verified in healthy subjects using GastroPlus TM to predict the plasma concentration-time profiles of voriconazole and PPIs. These models were then used to assess potential DDIs for voriconazole when administered with PPIs. The results indicated the PBPK model-simulated plasma concentration-time profiles of both voriconazole and PPIs were consistent with the observed profiles. In addition, the DDI simulations suggested that the PK values of voriconazole increased to various degrees when combined with several PPIs. The area under the plasma concentration-time curve for the time of the simulation (AUC 0- t ) of voriconazole was increased by 39%, 18%, 12% and 1% when co-administered with omeprazole, esomeprazole, lansoprazole and rabeprazole, respectively. Omeprazole was the most potent CYP2C19 inhibitor tested, whereas rabeprazole had no influence on voriconazole (omeprazole > esomeprazole > lansoprazole > rabeprazole). However, in consideration of the therapeutic concentration range, dosage adjustment of voriconazole is unnecessary regardless of which PPI was co-administered. Copyright © 2017 Elsevier B.V. and International Society of Chemotherapy. All rights reserved.

High-priority and low-priority drug-drug interactions in different international electronic health record systems: A comparative study.

PubMed

Cornu, Pieter; Phansalkar, Shobha; Seger, Diane L; Cho, Insook; Pontefract, Sarah; Robertson, Alexandra; Bates, David W; Slight, Sarah P

2018-03-01

To investigate whether alert warnings for high-priority and low-priority drug-drug interactions (DDIs) were present in five international electronic health record (EHR) systems, to compare and contrast the severity level assigned to them, and to establish the proportion of alerts that were overridden. We conducted a comparative, retrospective, multinational study using a convenience sample of 5 EHRs from the U.S., U.K., Republic of Korea and Belgium. Of the 15 previously defined, high-priority, class-based DDIs, alert warnings were found to exist for 11 in both the Korean and UK systems, 9 in the Belgian system, and all 15 in the two US systems. The specific combinations that were included in these class-based DDIs varied considerably in number, type and level of severity amongst systems. Alerts were only active for 8.4% (52/619) and 52.4% (111/212) of the specific drug-drug combinations contained in the Belgian and UK systems, respectively. Hard stops (not possible to override) existed in the US and UK systems only. The override rates for high-priority alerts requiring provider action ranged from 56.7% to 83.3%. Of the 33 previously defined low-priority DDIs, active alerts existed only in the US systems, for three class-based DDIs. The majority were non-interruptive. Alert warnings existed for most of the high-priority DDIs in the different EHRs but overriding them was easy in most of the systems. In addition to validating the high- and low-priority DDIs, this study reported a lack of standardization in DDI levels across different international knowledge bases. Copyright © 2017. Published by Elsevier B.V.

Chalcone Based Homodimeric PET Agent, 11C-(Chal)2DEA-Me, for Beta Amyloid Imaging: Synthesis and Bioevaluation.

PubMed

Chauhan, Kanchan; Tiwari, Anjani K; Chadha, Nidhi; Kaul, Ankur; Singh, Ajai Kumar; Datta, Anupama

2018-04-02

Homodimeric chalcone based 11 C-PET radiotracer, 11 C-(Chal) 2 DEA-Me, was synthesized, and binding affinity toward beta amyloid (Aβ) was evaluated. The computational studies revealed multiple binding of the tracer at the recognition sites of Aβ fibrils. The bivalent ligand 11 C-(Chal) 2 DEA-Me displayed higher binding affinity compared to the corresponding monomer, 11 C-Chal-Me, and classical Aβ agents. The radiolabeling yield with carbon-11 was 40-55% (decay corrected) with specific activity of 65-90 GBq/μmol. A significant ( p < 0.0001) improvement in the binding affinity of 11 C-(Chal) 2 DEA-Me with synthetic Aβ42 aggregates over the monomer, 11 C-Chal-Me, demonstrates the utility of the bivalent approach. The PET imaging and biodistribution data displayed suitable brain pharmacokinetics of both ligands with higher brain uptake in the case of the bivalent ligand. Metabolite analysis of healthy ddY mouse brain homogenates exhibited high stability of the radiotracers in the brain with >93% intact tracer at 30 min post injection. Both chalcone derivatives were fluorescent in nature and demonstrated significant changes in the emission properties after binding with Aβ42. The preliminary analysis indicates high potential of 11 C-(Chal) 2 DEA-Me as in vivo Aβ42 imaging tracer and highlights the significance of the bivalent approach to achieve a higher biological response for detection of early stages of amyloidosis.

Maternal Active Mastication during Prenatal Stress Ameliorates Prenatal Stress-Induced Lower Bone Mass in Adult Mouse Offspring

PubMed Central

Azuma, Kagaku; Ogura, Minori; Kondo, Hiroko; Suzuki, Ayumi; Hayashi, Sakurako; Iinuma, Mitsuo; Onozuka, Minoru; Kubo, Kin-ya

2017-01-01

Chronic psychological stress is a risk factor for osteoporosis. Maternal active mastication during prenatal stress attenuates stress response. The aim of this study is to test the hypothesis that maternal active mastication influences the effect of prenatal stress on bone mass and bone microstructure in adult offspring. Pregnant ddY mice were randomly divided into control, stress, and stress/chewing groups. Mice in the stress and stress/chewing groups were placed in a ventilated restraint tube for 45 minutes, 3 times a day, and was initiated on day 12 of gestation and continued until delivery. Mice in the stress/chewing group were allowed to chew a wooden stick during the restraint stress period. The bone response of 5-month-old male offspring was evaluated using quantitative micro-CT, bone histomorphometry, and biochemical markers. Prenatal stress resulted in significant decrease of trabecular bone mass in both vertebra and distal femur of the offspring. Maternal active mastication during prenatal stress attenuated the reduced bone formation and increased bone resorption, improved the lower trabecular bone volume and bone microstructural deterioration induced by prenatal stress in the offspring. These findings indicate that maternal active mastication during prenatal stress can ameliorate prenatal stress-induced lower bone mass of the vertebra and femur in adult offspring. Active mastication during prenatal stress in dams could be an effective coping strategy to prevent lower bone mass in their offspring. PMID:28553167

Maternal Active Mastication during Prenatal Stress Ameliorates Prenatal Stress-Induced Lower Bone Mass in Adult Mouse Offspring.

PubMed

Azuma, Kagaku; Ogura, Minori; Kondo, Hiroko; Suzuki, Ayumi; Hayashi, Sakurako; Iinuma, Mitsuo; Onozuka, Minoru; Kubo, Kin-Ya

2017-01-01

Chronic psychological stress is a risk factor for osteoporosis. Maternal active mastication during prenatal stress attenuates stress response. The aim of this study is to test the hypothesis that maternal active mastication influences the effect of prenatal stress on bone mass and bone microstructure in adult offspring. Pregnant ddY mice were randomly divided into control, stress, and stress/chewing groups. Mice in the stress and stress/chewing groups were placed in a ventilated restraint tube for 45 minutes, 3 times a day, and was initiated on day 12 of gestation and continued until delivery. Mice in the stress/chewing group were allowed to chew a wooden stick during the restraint stress period. The bone response of 5-month-old male offspring was evaluated using quantitative micro-CT, bone histomorphometry, and biochemical markers. Prenatal stress resulted in significant decrease of trabecular bone mass in both vertebra and distal femur of the offspring. Maternal active mastication during prenatal stress attenuated the reduced bone formation and increased bone resorption, improved the lower trabecular bone volume and bone microstructural deterioration induced by prenatal stress in the offspring. These findings indicate that maternal active mastication during prenatal stress can ameliorate prenatal stress-induced lower bone mass of the vertebra and femur in adult offspring. Active mastication during prenatal stress in dams could be an effective coping strategy to prevent lower bone mass in their offspring.

Assessment of safety and efficacy against Bordetella pertussis of a new tetanus-reduced dose diphtheria-acellular pertussis vaccine in a murine model.

PubMed

Kwon, Hyo Jin; Han, Seung Beom; Kim, Bo Ram; Kang, Kyu Ri; Huh, Dong Ho; Choi, Gi Sub; Ahn, Dong Ho; Kang, Jin Han

2017-04-04

Tetanus-reduced dose diphtheria-acellular pertussis (Tdap) vaccination during adolescence was introduced in response to the resurgence of pertussis in various countries. A new Tdap vaccine was manufactured in Korea as a countermeasure against a predicted Tdap vaccine shortage. This study was performed to evaluate the immunogenicity, safety, and protection efficacy against Bordetella pertussis of the new Tdap vaccine in a murine model. Four-week-old BABL/c mice were used for assessment of immunogenicity and protection efficacy. A single dose of primary diphtheria-tetanus-acellular pertussis (DTaP) vaccine was administered, followed by a single dose of Tdap booster vaccine after a 12-week interval. Anti-pertussis toxin (PT), anti-filamentous hemagglutinin (FHA), and anti-pertactin (PRN) IgG titers were measured before primary vaccination, and before and after booster vaccination. An intranasal challenge test was performed after booster vaccination to determine protection efficacy. To assess safety, mouse weight gain test and leukocytosis promotion test were performed using 4-week-old ddY female mice. Anti-PT and anti-FHA IgG titers after booster vaccination were significantly higher than those before booster vaccination with either the new vaccine or a commercially available Tdap vaccine (P = 0.01 for all occasions). After booster vaccination, no significant difference was observed between the two vaccines in antibody titers against pertussis antigens (P = 0.53 for anti-PT IgG, P = 0.91 for anti-FHA IgG, P = 0.39 for anti-PRN IgG). In the intranasal challenge test, inoculated B. pertussis was eradicated 7 days after infection. On days 4 and 7 after infection, colony counts of B. pertussis were not significantly different between the new and positive control vaccine groups (P = 1.00). Mean body weight changes and leukocyte counts of the new vaccine, positive control, and negative control groups were not significantly different 7 days after vaccination (P = 0.87 and P = 0.37, respectively). All leukocyte counts in the new vaccine group were within a mean ± 3 standard deviations range. A murine model involving a single dose primary DTaP vaccination followed by a single dose Tdap booster vaccination can be used for non-clinical studies of Tdap vaccines. The new Tdap vaccine manufactured in Korea exhibited comparable immunogenicity, protection efficacy, and safety with a commercially available Tdap vaccine.

Chronic stress enhances calcium mobilization and glutamate exocytosis in cerebrocortical synaptosomes from mice.

PubMed

Satoh, Eiki; Tada, Yuichi; Matsuhisa, Fumikazu

2011-11-01

Our previous study showed that acute restraint stress enhances depolarization-induced increases in intrasynaptosomal free calcium (Ca(2+)) concentration ([Ca(2+)](i)) and Ca(2+)-dependent glutamate release in mouse cerebrocortical nerve terminals (synaptosomes). In the present study, we investigated the effects of chronic stress on [Ca(2+)](i) and glutamate release in cerebrocortical synaptosomes from mice. Male ddY strain mice were randomly assigned to one of two experimental groups: control group and chronic stressed group. Mice in the chronic stressed group were subjected to immobilization stress for 2 hours daily for a period of 21 days. [Ca(2+)](i) and glutamate release in cerebrocortical synaptosomes isolated from the mice were determined by fura-2 fluorescence assay and enzyme-linked fluorometric assay, respectively. Chronic stress caused a significant increase in resting [Ca(2+)](i) and significantly enhanced the ability of the depolarizing agents K(+) and 4-aminopyridine (4-AP) to increase [Ca(2+)](i). It also brought about a significant increase in spontaneous (unstimulated) glutamate release and significantly enhanced K(+)- and 4-AP-evoked Ca(2+)-dependent glutamate release. Synaptosomes were more sensitive to the depolarizing agents at lower concentrations following chronic stress than after acute stress. The pretreatment of synaptosomes with a combination of omega-agatoxin IVA (a P-type Ca(2+) channel blocker) and omega-conotoxin GVIA (an N-type Ca(2+) channel blocker) completely suppressed the enhancements of [Ca(2+)](i) and Ca(2+)-dependent glutamate release in chronic stressed mice. These results indicate that chronic stress enhances depolarization-evoked glutamate release by increasing [Ca(2+)](i) via stimulation of Ca(2+) entry through P- and N-type Ca(2+) channels, and that chronic stress increases the sensitivity to depolarizing agents.

Combined effects of soy isoflavone and fish oil on ovariectomy-induced bone loss in mice.

PubMed

Uchida, Raina; Chiba, Hiroshige; Ishimi, Yoshiko; Uehara, Mariko; Suzuki, Kazuharu; Kim, Hyounju; Matsumoto, Akiyo

2011-07-01

Both soy isoflavone and n-3 polyunsaturated fatty acids are known to reduce the levels of bone-resorbing cytokines; however, the synergistic effects of these food ingredients have not been examined yet. This study was performed to elucidate the effect of concomitant intake of soy isoflavone and fish oil on bone mass in ovariectomized mice. Eight-week-old ddY female mice were subjected to ovariectomy (OVX) or sham surgery, and then fed an AIN-93G with safflower oil (So) as a control lipid source, isoflavone-supplemented safflower oil (So + I), fish oil instead of safflower oil (Fo) or isoflavone-supplemented fish oil (Fo + I) for 4 weeks. Femoral bone mineral density was significantly decreased by OVX; however, this decrease was inhibited by the intake of isoflavone and/or fish oil. Histomorphometric analyses showed that bone volume and trabecular thickness in the distal femoral trabecular bone were significantly lower in the So group than in the sham group, but those were restored in the Fo + I groups. The number of osteoclasts was significantly decreased by isoflavone intake. The increased rate of bone resorption after OVX was inhibited by isoflavone and/or fish oil. The serum concentration of tumor necrosis factor alpha was increased after OVX, but was significantly lower with the combination of isoflavone with fish oil than isoflavone or fish oil alone. The results of this study indicated that the intakes of soy isoflavone and/or fish oil might have ameliorating effects on bone loss due to OVX. Further, the concomitant intake of soy isoflavone and fish oil at a low dose showed better effects on cytokines related with bone resorption.

Analysis of drug-drug interactions among patients receiving antiretroviral regimens using data from a large open-source prescription database.

PubMed

Patel, Nimish; Borg, Peter; Haubrich, Richard; McNicholl, Ian

2018-06-14

Results of a study of contraindicated concomitant medication use among recipients of preferred antiretroviral therapy (ART) regimens are reported. A retrospective study was conducted to evaluate concomitant medication use in a cohort of previously treatment-naive, human immunodeficiency virus (HIV)-infected U.S. patients prescribed preferred ART regimens during the period April 2014-March 2015. Data were obtained from a proprietary longitudinal prescription database; elements retrieved included age, sex, and prescription data. The outcome of interest was the frequency of drug-drug interactions (DDIs) associated with concomitant use of contraindicated medications. Data on 25,919 unique treatment-naive patients who used a preferred ART regimen were collected. Overall, there were 384 instances in which a contraindicated medication was dispensed for concurrent use with a recommended ART regimen. Rates of contraindicated concomitant medication use differed significantly by ART regimen; the highest rate (3.2%) was for darunavir plus ritonavir plus emtricitabine-tenofovir disoproxil fumarate (DRV plus RTV plus FTC/TDF), followed by elvitegravir-cobicistat-emtricitabine-tenofovir disoproxil fumarate (EVG/c/FTC/TDF)(2.8%). The highest frequencies of DDIs were associated with ART regimens that included a pharmacoenhancing agent: DRV plus RTV plus FTC/TDF (3.2%) and EVG/c/FTC/TDF (2.8%). In a large population of treatment-naive HIV-infected patients, ART regimens that contained a pharmacoenhancing agent were involved most frequently in contraindicated medication-related DDIs. All of the DDIs could have been avoided by using therapeutic alternatives within the same class not associated with a DDI. Copyright © 2018 by the American Society of Health-System Pharmacists, Inc. All rights reserved.

Concentration dependence of the wings of a dipole-broadened magnetic resonance line in magnetically diluted lattices

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zobov, V. E., E-mail: rsa@iph.krasn.ru; Kucherov, M. M.

2017-01-15

The singularities of the time autocorrelation functions (ACFs) of magnetically diluted spin systems with dipole–dipole interaction (DDI), which determine the high-frequency asymptotics of autocorrelation functions and the wings of a magnetic resonance line, are studied. Using the self-consistent fluctuating local field approximation, nonlinear equations are derived for autocorrelation functions averaged over the independent random arrangement of spins (magnetic atoms) in a diamagnetic lattice with different spin concentrations. The equations take into account the specificity of the dipole–dipole interaction. First, due to its axial symmetry in a strong static magnetic field, the autocorrelation functions of longitudinal and transverse spin components aremore » described by different equations. Second, the long-range type of the dipole–dipole interaction is taken into account by separating contributions into the local field from distant and near spins. The recurrent equations are obtained for the expansion coefficients of autocorrelation functions in power series in time. From them, the numerical value of the coordinate of the nearest singularity of the autocorrelation function is found on the imaginary time axis, which is equal to the radius of convergence of these expansions. It is shown that in the strong dilution case, the logarithmic concentration dependence of the coordinate of the singularity is observed, which is caused by the presence of a cluster of near spins whose fraction is small but contribution to the modulation frequency is large. As an example a silicon crystal with different {sup 29}Si concentrations in magnetic fields directed along three crystallographic axes is considered.« less

The importance of regulation of blood glucose levels through activation of peripheral 5'-AMP-activated protein kinase on ischemic neuronal damage.

PubMed

Harada, Shinichi; Fujita-Hamabe, Wakako; Tokuyama, Shogo

2010-09-10

5'-AMP-activated protein kinase (AMPK) is a serine/threonine kinase that plays a key role in energy homeostasis. Recently, it was reported that centrally activated AMPK is involved in the development of ischemic neuronal damage, while the effect of peripherally activated AMPK on ischemic neuronal damage is not known. In addition, we have previously reported that the development of post-ischemic glucose intolerance could be one of the triggers for the aggravation of neuronal damage. In this study, we focused on effect of activation of peripheral or central AMPK on the development of ischemic neuronal damage. Male ddY mice were subjected to 2 h of middle cerebral artery occlusion (MCAO). Neuronal damage was estimated by histological and behavioral analysis after MCAO. In the liver and skeletal muscle, AMPK activity was not affected by MCAO. But, application of intraperitoneal metformin (250 mg/kg), an AMPK activator, significantly suppressed the development of post-ischemic glucose intolerance and ischemic neuronal damage without alteration of central AMPK activity. On the other hand, application of intracerebroventricular metformin (25, 100 microg/mouse) significantly exacerbated the development of neuronal damage observed on day 1 after MCAO, in a dose-dependent manner. These effects were significantly blocked by compound C, a specific AMPK inhibitor. These results suggest that central AMPK was activated by ischemic stress per se, however, peripheral AMPK was not altered. Furthermore, the regulation of post-ischemic glucose intolerance by activation of peripheral AMPK is of assistance for the suppression of cerebral ischemic neuronal damage. 2010 Elsevier B.V. All rights reserved.

Explicit spatiotemporal simulation of receptor-G protein coupling in rod cell disk membranes.

PubMed

Schöneberg, Johannes; Heck, Martin; Hofmann, Klaus Peter; Noé, Frank

2014-09-02

Dim-light vision is mediated by retinal rod cells. Rhodopsin (R), a G-protein-coupled receptor, switches to its active form (R(∗)) in response to absorbing a single photon and activates multiple copies of the G-protein transducin (G) that trigger further downstream reactions of the phototransduction cascade. The classical assumption is that R and G are uniformly distributed and freely diffusing on disk membranes. Recent experimental findings have challenged this view by showing specific R architectures, including RG precomplexes, nonuniform R density, specific R arrangements, and immobile fractions of R. Here, we derive a physical model that describes the first steps of the photoactivation cascade in spatiotemporal detail and single-molecule resolution. The model was implemented in the ReaDDy software for particle-based reaction-diffusion simulations. Detailed kinetic in vitro experiments are used to parametrize the reaction rates and diffusion constants of R and G. Particle diffusion and G activation are then studied under different conditions of R-R interaction. It is found that the classical free-diffusion model is consistent with the available kinetic data. The existence of precomplexes between inactive R and G is only consistent with the data if these precomplexes are weak, with much larger dissociation rates than suggested elsewhere. Microarchitectures of R, such as dimer racks, would effectively immobilize R but have little impact on the diffusivity of G and on the overall amplification of the cascade at the level of the G protein. Copyright © 2014 Biophysical Society. Published by Elsevier Inc. All rights reserved.

Involvement of decreased muscarinic receptor function in prepulse inhibition deficits in mice reared in social isolation

PubMed Central

Koda, K; Ago, Y; Yano, K; Nishimura, M; Kobayashi, H; Fukada, A; Takuma, K; Matsuda, T

2011-01-01

BACKGROUND AND PURPOSE We have previously reported that galantamine, a weak acetylcholinesterase inhibitor, improves prepulse inhibition (PPI) deficits in mice reared in social isolation. ACh receptors are involved in the underlying mechanism of PPI, but whether rearing in social isolation causes dysfunction of the cholinergic system is unknown. In this study, we examined the involvement of muscarinic receptors in the improvement of PPI deficits induced by galantamine, and whether the cholinergic system is altered in mice reared in isolation. EXPERIMENTAL APPROACH Three-week-old male ddY mice were housed in isolated cages for 6 weeks before the initiation of experiments to create PPI deficits. Cholinergic functions were determined by measuring the behavioural and neurochemical responses to nicotinic and muscarinic receptor agonists. KEY RESULTS The improvement by galantamine of social isolation-induced PPI deficits was blocked by scopolamine, a non-selective muscarinic antagonist, and telenzepine, a preferential M1 receptor antagonist. Activation of M1 receptors improved social isolation-induced PPI deficits. Social isolation did not affect choline acetyltransferase and acetylcholinesterase activities in the prefrontal cortex and hippocampus, but it reduced the locomotor-suppressive response to muscarinic agonist oxotremorine, but not to nicotine. The isolation also attenuated the M1 receptor agonist N-desmethylclozapine-induced increase in prefrontal dopamine release. CONCLUSIONS AND IMPLICATIONS Galantamine improves PPI deficits of mice reared in social isolation via activation of M1 receptors. Social isolation reduces the muscarinic, especially M1, receptor function and this is involved in PPI deficits. PMID:20958289

Combined effects of fangchinoline from Stephania tetrandra Radix and formononetin and calycosin from Astragalus membranaceus Radix on hyperglycemia and hypoinsulinemia in streptozotocin-diabetic mice.

PubMed

Ma, Wenjie; Nomura, Masaaki; Takahashi-Nishioka, Tatsuo; Kobayashi, Shinjiro

2007-11-01

The anti-hyperglycemic action of Stephania tetrandra Radix (Stephania) is potentiated by Astragalus membranaceus BUNGE Radix (Astragali) in streptozotocin (STZ)-diabetic ddY mice (Tsutsumi et al., Biol. Pharm. Bull., 26, 313 (2003)). Fangchinoline (0.3-3 mg/kg), a main constituent of Stephania, decreased the high level of blood glucose and increased the low level of blood insulin in STZ-diabetic mice. Here, we investigated the combined effects of fangchinoline with isoflavone or isoflavonoid components (formononetin, calycosin and ononin) of Astragali on the hyperglycemia and hypoinsulinemia of STZ-diabetic mice. Formononetin, calycosin and ononin (0.03-0.1 mg/kg) alone did not affect the blood glucose or blood insulin level of the diabetic mice. Formononetin and calycosin (0.03-0.1 mg/kg) potentiated the anti-hyperglycemic action of fangchinoline (0.3 mg/kg), but ononin did not. Formononetin (0.1 mg/kg) facilitated the fangchinoline-induced insulin release, and calycosin (0.1 mg/kg) also facilitated it, though without statistical significance. In conclusion, the combined effect of fangchinoline with formononetin and calycosin on hyperglycemia in the diabetic mice accounted well for the therapeutic effect of the combination of Stephania with Astragali in Boi-ogi-to. The anti-hyperglycemic action of formononetin appeared to be due to its potentiating action on insulin release. Our strategy for studying combinations of crude drugs and their components in Kampo medicine has uncovered new potentiating effects of formononetin and calycosin on the anti-hyperglycemic action of fangchinoline in STZ-diabetic mice.

Amelioration of Cold Injury-Induced Cortical Brain Edema Formation by Selective Endothelin ETB Receptor Antagonists in Mice

PubMed Central

Michinaga, Shotaro; Nagase, Marina; Matsuyama, Emi; Yamanaka, Daisuke; Seno, Naoki; Fuka, Mayu; Yamamoto, Yui; Koyama, Yutaka

2014-01-01

Brain edema is a potentially fatal pathological condition that often occurs in stroke and head trauma. Following brain insults, endothelins (ETs) are increased and promote several pathophysiological responses. This study examined the effects of ETB antagonists on brain edema formation and disruption of the blood-brain barrier in a mouse cold injury model (Five- to six-week-old male ddY mice). Cold injury increased the water content of the injured cerebrum, and promoted extravasation of both Evans blue and endogenous albumin. In the injury area, expression of prepro-ET-1 mRNA and ET-1 peptide increased. Intracerebroventricular (ICV) administration of BQ788 (ETB antagonist), IRL-2500 (ETB antagonist), or FR139317 (ETA antagonist) prior to cold injury significantly attenuated the increase in brain water content. Bolus administration of BQ788, IRL-2500, or FR139317 also inhibited the cold injury-induced extravasation of Evans blue and albumin. Repeated administration of BQ788 and IRL-2500 beginning at 24 h after cold injury attenuated both the increase in brain water content and extravasation of markers. In contrast, FR139317 had no effect on edema formation when administrated after cold injury. Cold injury stimulated induction of glial fibrillary acidic protein-positive reactive astrocytes in the injured cerebrum. Induction of reactive astrocytes after cold injury was attenuated by ICV administration of BQ788 or IRL-2500. These results suggest that ETB receptor antagonists may be an effective approach to ameliorate brain edema formation following brain insults. PMID:25000290

Practical analytical approach for the identification of biomarker candidates in prediabetic state based upon metabonomic study by ultraperformance liquid chromatography coupled to electrospray ionization time-of-flight mass spectrometry.

PubMed

Tsutsui, Haruhito; Maeda, Toshio; Toyo'oka, Toshimasa; Min, Jun Zhe; Inagaki, Shinsuke; Higashi, Tatsuya; Kagawa, Yoshiyuki

2010-08-06

The number of diabetic patients has recently been increasing worldwide. Thus, the discovery of potential diabetic biomarker(s), leading to the early detection and/or prevention of diabetes mellitus, is strongly required. The diagnosis of the prediabetic state in humans is a very difficult issue because of the lifestyle differences in each person and ethical consideration. Upon the basis of these considerations, animal experiments using ddY strain mice (ddY-H), which undergo naturally occurring diabetes along with age, were carried out in this study. Biomarker discovery based upon a metabonome study is now quite common, the same as that in the proteome analysis. Reversed-phase liquid chromatography-mass spectrometry (LC-MS) has mainly been used for the extensive analysis of low-molecular mass compounds including metabolites. The metabolites in the plasma of diabetic mice (ddY-H) and normal mice (ddY-L) were exhaustively separated and detected by ultraperformance liquid chromatography along with electrospray ionization time-of-flight mass spectrometry (UPLC-ESI-TOF-MS) using T3-C18 and HS-F5 columns. The biomarker candidates related to diabetes mellitus were extracted from the metabolite profiling of ddY-H and ddY-L at 5, 9 13, and 20 weeks old using a multivariate statistical analysis such as orthogonal partial least-squares-discriminant analysis (OPLS-DA). Various metabolites and unknown compounds were detected as biomarker candidates related to diabetic mellitus. Furthermore, the concentration of several metabolites on Lysine biosynthesis and Lysine degradation pathways were remarkably changed between the 9-week old ddY-H and ddY-L mice. Because a couple of biomarker candidates related to the prediabetic state were identified using the present approach, the metabolite profiling study could be helpful for understanding the abnormal state of various diseases.

ePlant and the 3D data display initiative: integrative systems biology on the world wide web.

PubMed

Fucile, Geoffrey; Di Biase, David; Nahal, Hardeep; La, Garon; Khodabandeh, Shokoufeh; Chen, Yani; Easley, Kante; Christendat, Dinesh; Kelley, Lawrence; Provart, Nicholas J

2011-01-10

Visualization tools for biological data are often limited in their ability to interactively integrate data at multiple scales. These computational tools are also typically limited by two-dimensional displays and programmatic implementations that require separate configurations for each of the user's computing devices and recompilation for functional expansion. Towards overcoming these limitations we have developed "ePlant" (http://bar.utoronto.ca/eplant) - a suite of open-source world wide web-based tools for the visualization of large-scale data sets from the model organism Arabidopsis thaliana. These tools display data spanning multiple biological scales on interactive three-dimensional models. Currently, ePlant consists of the following modules: a sequence conservation explorer that includes homology relationships and single nucleotide polymorphism data, a protein structure model explorer, a molecular interaction network explorer, a gene product subcellular localization explorer, and a gene expression pattern explorer. The ePlant's protein structure explorer module represents experimentally determined and theoretical structures covering >70% of the Arabidopsis proteome. The ePlant framework is accessed entirely through a web browser, and is therefore platform-independent. It can be applied to any model organism. To facilitate the development of three-dimensional displays of biological data on the world wide web we have established the "3D Data Display Initiative" (http://3ddi.org).

Bypassing Bypass Surgery and Other Success Stories from the National Institutes of Health

PubMed Central

Nijhara, Ruchika; Tidwell, J. Lille; Ferguson, Steven; Balakrishnan, Krishna

2009-01-01

After a heart attack, patients often undergo a procedure to open up the clogged artery and install a tiny meshlike device called a stent to keep the artery propped open. In most cases, the body reacts to this foreign object with scar-tissue formation, and the artery narrows again. To combat this re-clogging process, National Institutes of Health inventors developed paclitaxel-coated stents and later licensed it to Angiotech. Approved by the Food and Drug Administration in March 2004, these stents are expected to substantially reduce the use of coronary artery bypass surgery, an expensive operation now performed annually on 350,000-plus Americans. This and three other examples of NIH licensing success stories are described in this paper: (a) Kepivance, which improves the quality of life for cancer patients by eliminating mouth sores, (b) AIDS drug ddI, an important component of many combination drug therapies, and (c) Vitravene, the first and only antisense drug to be approved by FDA. These four examples will illustrate the success not only of the NIH licensing program, but also the innovative approaches taken by NIH inventors and the persistence of its commercial partners. This paper also highlights the business and legal lessons learned from these four cases. PMID:23730679

Prediction of Tidal Elevations and Barotropic Currents in the Gulf of Bone

NASA Astrophysics Data System (ADS)

Purnamasari, Rika; Ribal, Agustinus; Kusuma, Jeffry

2018-03-01

Tidal elevation and barotropic current predictions in the gulf of Bone have been carried out in this work based on a two-dimensional, depth-integrated Advanced Circulation (ADCIRC-2DDI) model for 2017. Eight tidal constituents which were obtained from FES2012 have been imposed along the open boundary conditions. However, even using these very high-resolution tidal constituents, the discrepancy between the model and the data from tide gauge is still very high. In order to overcome such issues, Green’s function approach has been applied which reduced the root-mean-square error (RMSE) significantly. Two different starting times are used for predictions, namely from 2015 and 2016. After improving the open boundary conditions, RMSE between observation and model decreased significantly. In fact, RMSEs for 2015 and 2016 decreased 75.30% and 88.65%, respectively. Furthermore, the prediction for tidal elevations as well as tidal current, which is barotropic current, is carried out. This prediction was compared with the prediction conducted by Geospatial Information Agency (GIA) of Indonesia and we found that our prediction is much better than one carried out by GIA. Finally, since there is no tidal current observation available in this area, we assume that, when tidal elevations have been fixed, then the tidal current will approach the actual current velocity.

Immunohistochemical expression of heat shock protein27 in the mouse dental pulp after immediate teeth separation

PubMed Central

2011-01-01

Aim After immediate teeth separation, expression of HSP27 in the mouse dental pulp was examined. Immunohistochemistry was performed to examine the incidence of HSP27 expression. Materials and methods A total of 36 8-week-old ddY mice were used as experimental subjects and a wedge was inserted in between maxillary right molars. The wedge was removed 30 min or 3 h after insertion. Animals were immediately sacrificed after the removal of wedge or until 1 week later and serial sections from paraffin-embedded tissues were prepared. Immunohistochemistry was carried out to examine the expression of HSP27. The untreated side served as the control. Results In the control group, the endothelial cells and some pulp fibroblasts weakly expressed HSP27 suggesting that the expression is due to mechanical stress brought about by physiological masticatory force and pressure from the tongue. In both 30 min and 3 h experimental groups, HSP27 expression was highest at 24 h after wedge removal and the expression remained the same or started to decrease thereafter. The expression decreased at the same level as that of the control group 1 week after wedge removal. Conclusion HSP27 may serve as an indicator of stimulus strong enough to show its expression. PMID:22027643

Momordica charantia constituents and antidiabetic screening of the isolated major compounds.

PubMed

Harinantenaina, Liva; Tanaka, Michi; Takaoka, Shigeru; Oda, Munehiro; Mogami, Orie; Uchida, Masayuki; Asakawa, Yoshinori

2006-07-01

Bioguided fractionation of the methanol extract of Momordica charantia dried gourds led to the isolation of three new cucurbitane triterpenoids (1-3), together with eight known compounds (4-11). The aglycone of momordicoside I was isolated from the ether soluble fraction in a high amount. The structures of the metabolites were established on the basis of one and two dimensional NMR spectroscopic evidence, X-ray analysis, and comparison with the reported data in the literature. A number of phytochemicals have been isolated from Momordica charantia but the constituents responsible for the hypoglycaemic/antihyperglycaemic activities have not been determined. Therefore, in order to evaluate the contribution of the cucurbitane triterpenoids of the ether fraction of M. charantia methanol extract to in vivo anti-diabetic effects, the major compounds, 5beta,19-epoxy-3beta,25-dihydroxycucurbita-6,23(E)-diene (4), and 3beta,7beta,25-trihydroxycucurbita-5,23(E)-dien-19-al (5) have been tested and have shown blood hypoglycaemic effects in the diabetes-induced male ddY mice strain at 400 mg/kg. The two aglycones of charantin did not show any hypoglycaemic effects. Our finding is the first demonstration that major pure cucurbutanoid compounds of M. charantia have in vivo hypoglycaemic effects.

Meta-analysis of two randomized controlled trials comparing combined zidovudine and didanosine therapy with combined zidovudine, didanosine, and nevirapine therapy in patients with HIV. INCAS study team.

PubMed

Raboud, J M; Rae, S; Vella, S; Harrigan, P R; Bucciardini, R; Fragola, V; Ricciardulli, D; Montaner, J S

1999-11-01

To extend the range of CD4 counts in which a plasma viral load nadir (pVL) <20 copies/ml was known to be predictive of the duration of virologic response. To determine whether baseline pVL is predictive of virologic response during the study periods. A meta-analysis was conducted of the original individual patient data from two randomized controlled trials comparing zidovudine (ZDV)/didanosine (ddI) with ZDV/ddI/nevirapine (NVP). In total, 87 patients received ZDV/ddI and 83 received ZDV/ddI/NVP. Study subjects on triple therapy with baseline pVL <100,000 copies/ml were more likely to achieve a pVL <400 copies/ml (odds ratio [OR] = 2.49; p = .02) and <20 copies/ml (OR = 4.76; p = .001) during the trial than those with baseline pVL > 100,000 copies/ml. Among triple therapy patients, the relative risk of virologic failure was higher for patients with higher baseline pVL (rate ratio [RR] = 2.51/log10 copies/ ml; p = .01), after controlling for compliance and pVL nadir. The relative risks of virologic failure associated with pVL nadir <20 copies/ml and between 21 and 400 copies/ml were .04 (p = .0001) and .56 (p = .26), respectively, compared with patients with a pVL nadir >400 copies/ml. We have extended our earlier results that achieving a pVL nadir <20 copies/ml is important for maintaining virologic suppression. In particular, we have demonstrated that a pVL nadir <20 copies/ml is at least fivefold more protective against virologic failure than achieving a pVL nadir between 20 and 400 copies/ml. Baseline pVL is significantly associated with the probability of achieving and sustaining virologic suppression.

Antiviral effects of Curcuma longa L. against dengue virus in vitro and in vivo

NASA Astrophysics Data System (ADS)

Ichsyani, M.; Ridhanya, A.; Risanti, M.; Desti, H.; Ceria, R.; Putri, D. H.; Sudiro, T. M.; Dewi, B. E.

2017-12-01

Dengue is the most common infective disease caused by dengue virus (DENV) and endemic diseases in tropical and subtropical areas. Until now, there is no specific antiviral for dengue infection. It is known that viral load is related to disease severity. Curcuma longa L. (turmeric) with curcumin as major active compound has been identified for its antiviral effect. This study to determine antiviral effect of C. longa extract on DENV-2 in vitro and in vivo along with its toxicity in liver and kidney of ddY mice. Antiviral activity (IC50) and toxicity (CC50) in vitro was examined on Huh7it-1 cells by focus assay and a MTT assay, respectively. To determine the selectivity index (SI), we used CC50 and IC50 value. The safe doses obtained were used for toxicity tests of liver and kidney with histopathological and biochemical observations. The C. longa extracts was given orally with dose of 0.147 mg/mL for each mice at 2 hours after injected with DENV-2 infected Huh7it-1 cells. Serum was collected from intraorbital at 6 hours and 24 hours after infection and focus assay was used to determine viral load. In this study, the acquired value of IC50 was 17,91 μg/mL whereas the value of CC50 was 85,4 μg/mL. The value of SI of C. longa was 4.8. In vivo, we found that C. longa remarkable reduced of viral load after 24 hour. Histopathological examination showed no specific abnormalities in liver and kidney. There was no significant increase in levels of SGPT, SGOT, urea, and creatinine. From this study it can be concluded that C. longa could potentially be used as antiviral against DENV with low cytotoxicity and effective inhibition.

Model based on GRID-derived descriptors for estimating CYP3A4 enzyme stability of potential drug candidates

NASA Astrophysics Data System (ADS)

Crivori, Patrizia; Zamora, Ismael; Speed, Bill; Orrenius, Christian; Poggesi, Italo

2004-03-01

A number of computational approaches are being proposed for an early optimization of ADME (absorption, distribution, metabolism and excretion) properties to increase the success rate in drug discovery. The present study describes the development of an in silico model able to estimate, from the three-dimensional structure of a molecule, the stability of a compound with respect to the human cytochrome P450 (CYP) 3A4 enzyme activity. Stability data were obtained by measuring the amount of unchanged compound remaining after a standardized incubation with human cDNA-expressed CYP3A4. The computational method transforms the three-dimensional molecular interaction fields (MIFs) generated from the molecular structure into descriptors (VolSurf and Almond procedures). The descriptors were correlated to the experimental metabolic stability classes by a partial least squares discriminant procedure. The model was trained using a set of 1800 compounds from the Pharmacia collection and was validated using two test sets: the first one including 825 compounds from the Pharmacia collection and the second one consisting of 20 known drugs. This model correctly predicted 75% of the first and 85% of the second test set and showed a precision above 86% to correctly select metabolically stable compounds. The model appears a valuable tool in the design of virtual libraries to bias the selection toward more stable compounds. Abbreviations: ADME - absorption, distribution, metabolism and excretion; CYP - cytochrome P450; MIFs - molecular interaction fields; HTS - high throughput screening; DDI - drug-drug interactions; 3D - three-dimensional; PCA - principal components analysis; CPCA - consensus principal components analysis; PLS - partial least squares; PLSD - partial least squares discriminant; GRIND - grid independent descriptors; GRID - software originally created and developed by Professor Peter Goodford.

The combined effects of soya isoflavones and resistant starch on equol production and trabecular bone loss in ovariectomised mice.

PubMed

Tousen, Yuko; Matsumoto, Yu; Matsumoto, Chiho; Nishide, Yoriko; Nagahata, Yuya; Kobayashi, Isao; Ishimi, Yoshiko

2016-07-01

Equol is a metabolite of the soya isoflavone (ISO) daidzein that is produced by intestinal microbiota. Equol has greater oestrogenic activity compared with other ISO, and it prevents bone loss in postmenopausal women. Resistant starch (RS), which has a prebiotic activity and is a dietary fibre, was reported to promote equol production. Conversely, the intestinal microbiota is reported to directly regulate bone health by reducing inflammatory cytokine levels and T-lymphocytes in bone. The present study evaluated the combined effects of diet supplemented with ISO and RS on intestinal microbiota, equol production, bone mineral density (BMD) and inflammatory gene expression in the bone marrow of ovariectomised (OVX) mice. Female ddY strain mice, aged 8 weeks, were either sham-operated (Sham, n 7) or OVX. OVX mice were randomly divided into the following four groups (seven per group): OVX control (OVX); OVX fed 0·05 % ISO diet (OVX+ISO); OVX fed 9 % RS diet (OVX+RS); and OVX fed 0·05 % ISO- and 9 % RS diet (OVX+ISO+RS). After 6 weeks, treatment with the combination of ISO and RS increased equol production, prevented the OVX-induced decline in trabecular BMD in the distal femur by modulating the enteric environment and altered OVX-induced inflammation-related gene expression in the bone marrow. However, there were no significant differences in bone parameters between the ISO+RS and ISO-alone groups in OVX mice. Our findings suggest that the combination of ISO and RS might alter intestinal microbiota and immune status in the bone marrow, resulting in attenuated bone resorption in OVX mice.

The application of physiologically based pharmacokinetic modelling to assess the impact of antiretroviral-mediated drug-drug interactions on piperaquine antimalarial therapy during pregnancy.

PubMed

Olafuyi, Olusola; Coleman, Michael; Badhan, Raj K S

2017-11-01

Antimalarial therapy during pregnancy poses important safety concerns due to potential teratogenicity and maternal physiological and biochemical changes during gestation. Piperaquine (PQ) has gained interest for use in pregnancy in response to increasing resistance towards sulfadoxine-pyrimethamine in sub-Saharan Africa. Coinfection with HIV is common in many developing countries, however, little is known about the impact of antiretroviral (ARV) mediated drug-drug interaction (DDI) on piperaquine pharmacokinetics during pregnancy. This study applied mechanistic pharmacokinetic modelling to predict pharmacokinetics in non-pregnant and pregnant patients, which was validated in distinct customised population groups from Thailand, Sudan and Papua New Guinea. In each population group, no significant differences in day 7 concentrations were observed during different gestational weeks (GW) (weeks 10-40), supporting the notion that piperaquine is safe throughout pregnancy with consistent pharmacokinetics, although possible teratogenicity may limit this. Antiretroviral-mediated DDIs (efavirenz and ritonavir) had moderate effects on piperaquine during different gestational weeks with a predicted AUC ratio in the range 0.56-0.8 and 1.64-1.79 for efavirenz and ritonavir, respectively, over GW 10-40, with a reduction in circulating human serum albumin significantly reducing the number of subjects attaining the day 7 (post-dose) therapeutic efficacy concentrations under both efavirenz and ritonavir DDIs. This present model successfully mechanistically predicted the pharmacokinetics of piperaquine in pregnancy to be unchanged with respect to non-pregnant women, in the light of factors such as malaria/HIV co-infection. However, antiretroviral-mediated DDIs could significantly alter piperaquine pharmacokinetics. Further model refinement will include collation of relevant physiological and biochemical alterations common to HIV/malaria patients. Copyright © 2017 John Wiley & Sons, Ltd.

Adenosine 3′,5′-cyclic monophosphate (cAMP)-dependent phosphoregulation of mitochondrial complex I is inhibited by nucleoside reverse transcriptase inhibitors

PubMed Central

Lund, Kaleb C.; Wallace, Kendall B.

2008-01-01

Nucleoside analog reverse transcriptase inhibitors (NRTI) are known to directly inhibit mitochondrial complex I activity as well as various mitochondrial kinases. Recent observations that complex I activity and superoxide production are modulated through cAMP-dependent phosphorylation suggests a mechanism through which NRTIs may affect mitochondrial respiration via kinase-dependent protein phosphorylation. In the current study we examine the potential for NRTIs to inhibit the cAMP-dependent phosphorylation of complex I and the associated NADH:CoQ oxidoreductase activities and rates of superoxide production using HepG2 cells. Phosphoprotein staining of immunocaptured complex I revealed that 3′-azido-3′-deoxythymidine (AZT; 10 and 50 μM), AZT monophosphate (150 μM), and 2′,3′-dideoxycytidine (ddC; 1μM) prevented the phosphorylation of the NDUFB11 subunit of complex I. This was associated with a decrease in complex I activity with AZT and AZT monophosphate only. In the presence of succinate, superoxide production was increased with 2′,3′-dideoxyinosine (ddI; 10 μM) and ddC (1 μM). In the presence of succinate + cAMP AZT showed an inverse dose-dependent effect on superoxide production. None of the NRTIs examined inhibit PKA activity suggesting that the observed effects are due to a direct interaction with complex I. These data demonstrate a direct effect of NRTIs on cAMP-dependent regulation of mitochondrial bioenergetics independent of DNA polymerase-γ activity; in the case of AZT these observations may provide a mechanism for the observed long-term toxicity with this drug. PMID:17904600

Androgen receptor polyglutamine expansion drives age-dependent quality control defects and muscle dysfunction.

PubMed

Nath, Samir R; Yu, Zhigang; Gipson, Theresa A; Marsh, Gregory B; Yoshidome, Eriko; Robins, Diane M; Todi, Sokol V; Housman, David E; Lieberman, Andrew P

2018-05-29

Skeletal muscle has emerged as a critical, disease-relevant target tissue in spinal and bulbar muscular atrophy, a degenerative disorder of the neuromuscular system caused by a CAG/polyglutamine (polyQ) expansion in the androgen receptor (AR) gene. Here, we used RNA-Seq to identify pathways that are disrupted in diseased muscle using AR113Q knock-in mice. This analysis unexpectedly identified significantly diminished expression of numerous ubiquitin-proteasome pathway genes in AR113Q muscle, encoding approximately 30% of proteasome subunits and 20% of E2 ubiquitin conjugases. These changes were age-, hormone- and glutamine length-dependent and arose due to a toxic gain-of-function conferred by the mutation. Moreover, altered gene expression was associated with decreased level of the proteasome transcription factor NRF1 and its activator DDI2 and resulted in diminished proteasome activity. Ubiquitinated ADRM1 was detected in AR113Q muscle, indicating the occurrence of stalled proteasomes in mutant mice. Finally, diminished expression of Drosophila orthologues of NRF1 or ADRM1 promoted the accumulation of polyQ AR protein and increased toxicity. Collectively, these data indicate that AR113Q muscle develops progressive proteasome dysfunction that leads to the impairment of quality control and the accumulation of polyQ AR protein, key features that contribute to the age-dependent onset and progression of this disorder.

Retinal protective effects of topically administered agmatine on ischemic ocular injury caused by transient occlusion of the ophthalmic artery

PubMed Central

Hong, S.; Hara, H.; Shimazawa, M.; Hyakkoku, K.; Kim, C.Y.; Seong, G.J.

2012-01-01

Agmatine, an endogenous polyamine and putative neuromodulator, is known to have neuroprotective effects on various neurons in the central nervous system. We determined whether or not topically administered agmatine could reduce ischemic retinal injury. Transient ocular ischemia was achieved by intraluminal occlusion of the middle cerebral artery of ddY mice (30-35 g) for 2 h, which is known to also induce occlusion of the ophthalmic artery. In the agmatine group (N = 6), a 1.0 mM agmatine-containing ophthalmic solution was administered four times daily for 2 weeks before occlusion. In the control group (N = 6), a 0.1% hyaluronic acid ophthalmic solution was instilled at the same times. At 22 h after reperfusion, the eyeballs were enucleated and the retinal sections were stained by terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL). Transient ocular ischemia induced apoptosis of retinal cells in the entire retinal layer, and topically administered agmatine can significantly reduce this ischemic retinal injury. The proportion of apoptotic cells was definitely decreased (P < 0.001; Kruskal-Wallis test). Overall, we determined that topical agmatine application effectively decreases retinal damage in an in vivo ocular ischemic injury model. This implies that agmatine is a good candidate as a direct neuroprotective agent for eyes with ocular ischemic diseases. PMID:22331138

AIDS therapy with two, three or four agent combinations, applied in short sequences, differing from each other by drug rotation. I. First of two parts: a phase I trial equivalent, concerning five virostatics: AZT, ddI, ddC, acriflavine and an ellipticine analogue.

PubMed

Mathé, G; Pontiggia, P; Orbach-Arbouys, S; Triana, K; Ambetima, N; Morette, C; Hallard, M; Blanquet, D

1996-01-01

We have individually treated ten AIDS patients whose CD4 numbers were inferior to 200/mm3, with the five following HIV1 virostatics: a) azido-deoxythymidine (AZT), dideoxyinosine (ddI) and dideoxycytidine (ddC), which affect the same viral target, retrotranscriptase, b) acriflavine (ACF) and methyl-hydroxy-ellipticine (MHE) which we have discovered to be strong virostatics in vivo, in mice, against Friend's virus, and in man, against AZT resistant HIV1. We have shown that their combinations with AZT, hitting three viral targets, reduces in mice, the blood Friend's virus load below detectable level. Due to the short doubling time of HIV1, AIDS therapy must be continuous, and to allow the best tolerance, the five virostatic combinations were applied in short, three-week sequences, each differing as much as possible from the former and from the following one, due to drug rotation [1]. Among the ten patients, a) three received the two-drug combinations for 15 to 30 months, followed by the three-drug combinations, b) three received the three-drug combinations from the beginning, c) four received the four-drug combinations also from the beginning, two having less than 10 CD4/mm3 at initiation of treatment, and two having more than 100. The tolerance was remarkable: the only side-effect being macrocytosis. The application of the two-drug combination sequences maintained stable CD4 levels in two subjects whose viral load (the evaluation of which had became available) was, at the end of this period, of 4,486 and 39,238 RNA copies. The third subject who had received, an intensive UV irradiation for a psoriasis, presented an irreversible decrease in his CD4 count and a high viral load (1,352,495 RNA copies/mL) at the end of the two-drug period. Fifteen to 25 months after the shift to the three-drug combinations, the viral load decreased, from 39,328 to 13,291 in one of the non-UV irradiated subjects, and from 1,352,495 to 314,387 in the irradiated one. No subject had an increase in CD4 number. In the three patients having initially received the three-drug combinations, a very strong decrease of viral load was registered after periods of observation varying from 77 to 40 months, while the CD4 counts increased moderately in two subjects, and noticeably in the third (from 126 to 266). Out of the four subjects initially treated with four-drug combinations, the two with less than 10 CD4/mm3 had a moderate decrease in viral load in about three months, and the CD4 increased from 9 to 34/mm3 in one. But the two subjects, because of opportunistic infections and psychological reasons, abandoned their treatments. In the two subjects who had more than 100 CD4/mm2 at initiation of the four-drug combination treatment, the viral load decreased to undetectable levels after four months: but their CD4 counts, after some oscillations, had very moderately increased at the end of the observation period (respectively, from 200 to 222, and from 129 to 134). In practice, these results suggest the interest of conducting phase II or III studies of AIDS treatment protocols, starting with the four-drug combination model, and attempting to maintain the effect with the three-drug combination one. As for theoretical considerations, one must underline the contrast between the remarkable reduction of the viral load and the usually moderate increase of the CD4 counts. The study but not the trial has been interrupted, due to the unavailability of three antiproteases, saquinavir, ritonavir and indinavir, which are now introduced in the same type of combinations, one by one, in replacement of one of the studied agents as shown in figure 1. The effect of increasing the total number of virostatics from five to eight will be published in the second part of this article series.

Comparative analysis of the intestinal flora in type 2 diabetes and nondiabetic mice

PubMed Central

Horie, Masanori; Miura, Takamasa; Hirakata, Satomi; Hosoyama, Akira; Sugino, Sakiko; Umeno, Aya; Murotomi, Kazutoshi; Yoshida, Yasukazu; Koike, Taisuke

2017-01-01

A relationship between type 2 diabetes mellitus (T2DM) and intestinal flora has been suggested since development of analysis technology for intestinal flora. An animal model of T2DM is important for investigation of T2DM. Although there are some animal models of T2DM, a comparison of the intestinal flora of healthy animals with that of T2DM animals has not yet been reported. The intestinal flora of Tsumura Suzuki Obese Diabetes (TSOD) mice was compared with that of Tsumura, Suzuki, Non Obesity (TSNO) mice in the present study. The TSOD mice showed typical type 2 diabetes symptoms, which were high-fat diet-independent. The TSOD and the TSNO mouse models were derived from the same strain, ddY. In this study, we compared the intestinal flora of TSOD mice with that if TSNO mice at 5 and 12 weeks of age. We determined that that the number of operational taxonomic units (OTUs) was significantly higher in the cecum of TSOD mice than in that of TSNO mice. The intestinal flora of the cecum and that of the feces were similar between the TSNO and the TSOD strains. The dominant bacteria in the cecum and feces were of the phyla Firmicutes and Bacteroidetes. However, the content of some bacterial species varied between the two strains. The percentage of Lactobacillus spp. within the general intestinal flora was higher in TSOD mice than in TSNO mice. In contrast, the percentages of order Bacteroidales and family Lachnospiraceae were higher in TSNO mice than in TSOD mice. Some species were observed only in TSOD mice, such as genera Turicibacter and SMB53 (family Clostridiaceae), the percentage of which were 3.8% and 2.0%, respectively. Although further analysis of the metabolism of the individual bacteria in the intestinal flora is essential, genera Turicibacter and SMB53 may be important for the abnormal metabolism of type 2 diabetes. PMID:28701620

Comparative analysis of the intestinal flora in type 2 diabetes and nondiabetic mice.

PubMed

Horie, Masanori; Miura, Takamasa; Hirakata, Satomi; Hosoyama, Akira; Sugino, Sakiko; Umeno, Aya; Murotomi, Kazutoshi; Yoshida, Yasukazu; Koike, Taisuke

2017-10-30

A relationship between type 2 diabetes mellitus (T2DM) and intestinal flora has been suggested since development of analysis technology for intestinal flora. An animal model of T2DM is important for investigation of T2DM. Although there are some animal models of T2DM, a comparison of the intestinal flora of healthy animals with that of T2DM animals has not yet been reported. The intestinal flora of Tsumura Suzuki Obese Diabetes (TSOD) mice was compared with that of Tsumura, Suzuki, Non Obesity (TSNO) mice in the present study. The TSOD mice showed typical type 2 diabetes symptoms, which were high-fat diet-independent. The TSOD and the TSNO mouse models were derived from the same strain, ddY. In this study, we compared the intestinal flora of TSOD mice with that if TSNO mice at 5 and 12 weeks of age. We determined that that the number of operational taxonomic units (OTUs) was significantly higher in the cecum of TSOD mice than in that of TSNO mice. The intestinal flora of the cecum and that of the feces were similar between the TSNO and the TSOD strains. The dominant bacteria in the cecum and feces were of the phyla Firmicutes and Bacteroidetes. However, the content of some bacterial species varied between the two strains. The percentage of Lactobacillus spp. within the general intestinal flora was higher in TSOD mice than in TSNO mice. In contrast, the percentages of order Bacteroidales and family Lachnospiraceae were higher in TSNO mice than in TSOD mice. Some species were observed only in TSOD mice, such as genera Turicibacter and SMB53 (family Clostridiaceae), the percentage of which were 3.8% and 2.0%, respectively. Although further analysis of the metabolism of the individual bacteria in the intestinal flora is essential, genera Turicibacter and SMB53 may be important for the abnormal metabolism of type 2 diabetes.

Characterization of the hepatic cytochrome P450 enzymes involved in the metabolism of 25I-NBOMe and 25I-NBOH.

PubMed

Nielsen, Line Marie; Holm, Niels Bjerre; Leth-Petersen, Sebastian; Kristensen, Jesper Langgaard; Olsen, Lars; Linnet, Kristian

2017-05-01

The dimethoxyphenyl-N-((2-methoxyphenyl)methyl)ethanamine (NBOMe) compounds are potent serotonin 5-HT2A receptor agonists and have recently been subject to recreational use due to their hallucinogenic effects. Use of NBOMe compounds has been known since 2011, and several non-fatal and fatal intoxication cases have been reported in the scientific literature. The aim of this study was to determine the importance of the different cytochrome P450 enzymes (CYP) involved in the metabolism of 2-(4-iodo-2,5-dimethoxyphenyl)-N-(2methoxybenzyl)ethanamine (25I-NBOMe) and 2-[[2-(4-iodo-2,5dimethoxyphenyl)ethylamino]methyl]phenol (25I-NBOH) and to characterize the metabolites. The following approaches were used to identify the main enzymes involved in primary metabolism: incubation with a panel of CYP and monoamine oxidase (MAO) enzymes and incubation in pooled human liver microsomes (HLM) with and without specific CYP chemical inhibitors. The study was further substantiated by an evaluation of 25I-NBOMe and 25I-NBOH metabolism in single donor HLM. The metabolism pathways of 25I-NBOMe and 25I-NBOH were NADPHdependent with intrinsic clearance values of (CLint) of 70.1 and 118.7 mL/min/kg, respectively. The biotransformations included hydroxylation, O-demethylation, N-dealkylation, dehydrogenation, and combinations thereof. The most abundant metabolites were all identified by retention time and spectrum matching with synthesized reference standards. The major CYP enzymes involved in the metabolism of 25I-NBOMe and 25INBOH were identified as CYP3A4 and CYP2D6, respectively. The compound 25I-NBOH was also liable to direct glucuronidation, which may diminish the impact of CYP2D6 genetic polymorphism. Users of 25I-NBOMe may be subject to drug-drug interactions (DDI) if 25I-NBOMe is taken with a strong CYP3A4 inhibitor. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Chronic Pain: How Challenging Are DDIs in the Analgesic Treatment of Inpatients with Multiple Chronic Conditions?

PubMed Central

Siebenhuener, Klarissa; Eschmann, Emmanuel; Kienast, Alexander; Schneider, Dominik; Minder, Christoph E.; Saller, Reinhard; Zimmerli, Lukas; Blaser, Jürg; Battegay, Edouard

2017-01-01

Background Chronic pain is common in multimorbid patients. However, little is known about the implications of chronic pain and analgesic treatment on multimorbid patients. This study aimed to assess chronic pain therapy with regard to the interaction potential in a sample of inpatients with multiple chronic conditions. Methods and Findings We conducted a retrospective study with all multimorbid inpatients aged ≥18 years admitted to the Department of Internal Medicine of University Hospital Zurich in 2011 (n = 1,039 patients). Data were extracted from the electronic health records and reviewed. We identified 433 hospitalizations of patients with chronic pain and analyzed their combinations of chronic conditions (multimorbidity). We then classified all analgesic prescriptions according to the World Health Organization (WHO) analgesic ladder. Furthermore, we used a Swiss drug-drug interactions knowledge base to identify potential interactions between opioids and other drug classes, in particular coanalgesics and other concomitant drugs. Chronic pain was present in 38% of patients with multimorbidity. On average, patients with chronic pain were aged 65.7 years and had a mean number of 6.6 diagnoses. Hypertension was the most common chronic condition. Chronic back pain was the most common painful condition. Almost 90% of patients were exposed to polypharmacotherapy. Of the chronic pain patients, 71.1% received opioids for moderate to severe pain, 43.4% received coanalgesics. We identified 3,186 potential drug-drug interactions, with 17% classified between analgesics (without coanalgesics). Conclusions Analgesic drugs-related DDIs, in particular opioids, in multimorbid patients are often complex and difficult to assess by using DDI knowledge bases alone. Drug-multimorbidity interactions are not sufficiently investigated and understood. Today, the scientific literature is scarce for chronic pain in combination with multiple coexisting medical conditions and medication regimens. Our work may provide useful information to enable further investigations in multimorbidity research within the scope of potential interactions and chronic pain. PMID:28046033

Chronic Pain: How Challenging Are DDIs in the Analgesic Treatment of Inpatients with Multiple Chronic Conditions?

PubMed

Siebenhuener, Klarissa; Eschmann, Emmanuel; Kienast, Alexander; Schneider, Dominik; Minder, Christoph E; Saller, Reinhard; Zimmerli, Lukas; Blaser, Jürg; Battegay, Edouard; Holzer, Barbara M

2017-01-01

Chronic pain is common in multimorbid patients. However, little is known about the implications of chronic pain and analgesic treatment on multimorbid patients. This study aimed to assess chronic pain therapy with regard to the interaction potential in a sample of inpatients with multiple chronic conditions. We conducted a retrospective study with all multimorbid inpatients aged ≥18 years admitted to the Department of Internal Medicine of University Hospital Zurich in 2011 (n = 1,039 patients). Data were extracted from the electronic health records and reviewed. We identified 433 hospitalizations of patients with chronic pain and analyzed their combinations of chronic conditions (multimorbidity). We then classified all analgesic prescriptions according to the World Health Organization (WHO) analgesic ladder. Furthermore, we used a Swiss drug-drug interactions knowledge base to identify potential interactions between opioids and other drug classes, in particular coanalgesics and other concomitant drugs. Chronic pain was present in 38% of patients with multimorbidity. On average, patients with chronic pain were aged 65.7 years and had a mean number of 6.6 diagnoses. Hypertension was the most common chronic condition. Chronic back pain was the most common painful condition. Almost 90% of patients were exposed to polypharmacotherapy. Of the chronic pain patients, 71.1% received opioids for moderate to severe pain, 43.4% received coanalgesics. We identified 3,186 potential drug-drug interactions, with 17% classified between analgesics (without coanalgesics). Analgesic drugs-related DDIs, in particular opioids, in multimorbid patients are often complex and difficult to assess by using DDI knowledge bases alone. Drug-multimorbidity interactions are not sufficiently investigated and understood. Today, the scientific literature is scarce for chronic pain in combination with multiple coexisting medical conditions and medication regimens. Our work may provide useful information to enable further investigations in multimorbidity research within the scope of potential interactions and chronic pain.

Structural Insights into HIV Reverse Transcriptase Mutations Q151M and Q151M Complex That Confer Multinucleoside Drug Resistance

DOE Office of Scientific and Technical Information (OSTI.GOV)

Das, Kalyan; Martinez, Sergio E.; Arnold, Eddy

HIV-1 reverse transcriptase (RT) is targeted by multiple drugs. RT mutations that confer resistance to nucleoside RT inhibitors (NRTIs) emerge during clinical use. Q151M and four associated mutations, A62V, V75I, F77L, and F116Y, were detected in patients failing therapies with dideoxynucleosides (didanosine [ddI], zalcitabine [ddC]) and/or zidovudine (AZT). The cluster of the five mutations is referred to as the Q151M complex (Q151Mc), and an RT or virus containing Q151Mc exhibits resistance to multiple NRTIs. To understand the structural basis for Q151M and Q151Mc resistance, we systematically determined the crystal structures of the wild-type RT/double-stranded DNA (dsDNA)/dATP (complex I), wild-type RT/dsDNA/ddATPmore » (complex II), Q151M RT/dsDNA/dATP (complex III), Q151Mc RT/dsDNA/dATP (complex IV), and Q151Mc RT/dsDNA/ddATP (complex V) ternary complexes. The structures revealed that the deoxyribose rings of dATP and ddATP have 3'-endo and 3'-exo conformations, respectively. The single mutation Q151M introduces conformational perturbation at the deoxynucleoside triphosphate (dNTP)-binding pocket, and the mutated pocket may exist in multiple conformations. The compensatory set of mutations in Q151Mc, particularly F116Y, restricts the side chain flexibility of M151 and helps restore the DNA polymerization efficiency of the enzyme. The altered dNTP-binding pocket in Q151Mc RT has the Q151-R72 hydrogen bond removed and has a switched conformation for the key conserved residue R72 compared to that in wild-type RT. On the basis of a modeled structure of hepatitis B virus (HBV) polymerase, the residues R72, Y116, M151, and M184 in Q151Mc HIV-1 RT are conserved in wild-type HBV polymerase as residues R41, Y89, M171, and M204, respectively; functionally, both Q151Mc HIV-1 and wild-type HBV are resistant to dideoxynucleoside analogs.« less

Drug-drug interaction predictions with PBPK models and optimal multiresponse sampling time designs: application to midazolam and a phase I compound. Part 2: clinical trial results.

PubMed

Chenel, Marylore; Bouzom, François; Cazade, Fanny; Ogungbenro, Kayode; Aarons, Leon; Mentré, France

2008-12-01

To compare results of population PK analyses obtained with a full empirical design (FD) and an optimal sparse design (MD) in a Drug-Drug Interaction (DDI) study aiming to evaluate the potential CYP3A4 inhibitory effect of a drug in development, SX, on a reference substrate, midazolam (MDZ). Secondary aim was to evaluate the interaction of SX on MDZ in the in vivo study. Methods To compare designs, real data were analysed by population PK modelling technique using either FD or MD with NONMEM FOCEI for SX and with NONMEM FOCEI and MONOLIX SAEM for MDZ. When applicable a Wald test was performed to compare model parameter estimates, such as apparent clearance (CL/F), across designs. To conclude on the potential interaction of SX on MDZ PK, a Student paired test was applied to compare the individual PK parameters (i.e. log(AUC) and log(C(max))) obtained either by a non-compartmental approach (NCA) using FD or from empirical Bayes estimates (EBE) obtained after fitting the model separately on each treatment group using either FD or MD. For SX, whatever the design, CL/F was well estimated and no statistical differences were found between CL/F estimated values obtained with FD (CL/F = 8.2 l/h) and MD (CL/F = 8.2 l/h). For MDZ, only MONOLIX was able to estimate CL/F and to provide its standard error of estimation with MD. With MONOLIX, whatever the design and the administration setting, MDZ CL/F was well estimated and there were no statistical differences between CL/F estimated values obtained with FD (72 l/h and 40 l/h for MDZ alone and for MDZ with SX, respectively) and MD (77 l/h and 45 l/h for MDZ alone and for MDZ with SX, respectively). Whatever the approach, NCA or population PK modelling, and for the latter approach, whatever the design, MD or FD, comparison tests showed that there was a statistical difference (P < 0.0001) between individual MDZ log(AUC) obtained after MDZ administration alone and co-administered with SX. Regarding C(max), there was a statistical difference (P < 0.05) between individual MDZ log(C(max)) obtained under the 2 administration settings in all cases, except with the sparse design with MONOLIX. However, the effect on C(max) was small. Finally, SX was shown to be a moderate CYP3A4 inhibitor, which at therapeutic doses increased MDZ exposure by a factor of 2 in average and almost did not affect the C(max). The optimal sparse design enabled the estimation of CL/F of a CYP3A4 substrate and inhibitor when co-administered together and to show the interaction leading to the same conclusion as the full empirical design.

Drug-drug interaction predictions with PBPK models and optimal multiresponse sampling time designs: application to midazolam and a phase I compound. Part 2: clinical trial results

PubMed Central

Chenel, Marylore; Bouzom, François; Cazade, Fanny; Ogungbenro, Kayode; Aarons, Leon; Mentré, France

2008-01-01

Purpose To compare results of population PK analyses obtained with a full empirical design (FD) and an optimal sparse design (MD) in a Drug-Drug Interaction (DDI) study aiming to evaluate the potential CYP3A4 inhibitory effect of a drug in development, SX, on a reference substrate, midazolam (MDZ). Secondary aim was to evaluate the interaction of SX on MDZ in the in vivo study. Methods To compare designs, real data were analysed by population PK modelling using either FD or MD with NONMEM FOCEI for SX and with NONMEM FOCEI and MONOLIX SAEM for MDZ. When applicable a Wald’s test was performed to compare model parameter estimates, such as apparent clearance (CL/F), across designs. To conclude on the potential interaction of SX on MDZ PK, a Student paired test was applied to compare the individual PK parameters (i.e. log(AUC) and log(Cmax)) obtained either by a non-compartmental approach (NCA) using FD or from empirical Bayes estimates (EBE) obtained after fitting the model separately on each treatment group using either FD or MD. Results For SX, whatever the design, CL/F was well estimated and no statistical differences were found between CL/F estimated values obtained with FD (CL/F = 8.2 L/h) and MD (CL/F = 8.2 L/h). For MDZ, only MONOLIX was able to estimate CL/F and to provide its standard error of estimation with MD. With MONOLIX, whatever the design and the administration setting, MDZ CL/F was well estimated and there were no statistical differences between CL/F estimated values obtained with FD (72 L/h and 40 L/h for MDZ alone and for MDZ with SX, respectively) and MD (77 L/h and 45 L/h for MDZ alone and for MDZ with SX, respectively). Whatever the approach, NCA or population PK modelling, and for the latter approach, whatever the design, MD or FD, comparison tests showed that there was a statistical difference (p<0.0001) between individual MDZ log(AUC) obtained after MDZ administration alone and co-administered with SX. Regarding Cmax, there was a statistical difference (p<0.05) between individual MDZ log(Cmax) obtained under the 2 administration settings in all cases, except with the sparse design with MONOLIX. However, the effect on Cmax was small. Finally, SX was shown to be a moderate CYP3A4 inhibitor, which at therapeutic doses increased MDZ exposure by a factor 2 in average and almost did not affect the Cmax. Conclusion The optimal sparse design enabled the estimation of CL/F of a CYP3A4 substrate and inhibitor when co-administered together and to show the interaction leading to the same conclusion than the full empirical design. PMID:19130187

In vitro assessment of the interactions of dopamine β-hydroxylase inhibitors with human P-glycoprotein and Breast Cancer Resistance Protein.

PubMed

Bicker, Joana; Alves, Gilberto; Fortuna, Ana; Soares-da-Silva, Patrício; Falcão, Amílcar

2018-05-30

Inhibition of the biosynthesis of noradrenaline is a currently explored strategy for the treatment of hypertension, congestive heart failure and pulmonary arterial hypertension. While some dopamine β-hydroxylase (DBH) inhibitors cross the blood-brain barrier (BBB) and cause central as well as peripheral effects (nepicastat), others have limited access to the brain (etamicastat, zamicastat). In this context, peripheral selectivity is clinically advantageous, in order to prevent alterations of noradrenaline levels in the CNS and the occurrence of adverse central effects. A limited brain exposure results from the combination of several factors, such as a reduced passive permeability or affinity for efflux transporters, but efflux liabilities may also lead to unwanted drug-drug interactions (DDIs) in the presence of co-administered substrates or inhibitors. Thus, the purpose of the study herein presented was to explore the interaction of P-glycoprotein (P-gp) and Breast Cancer Resistance Protein (BCRP), the two major efflux transporters of the BBB that hamper the entry of several drugs to the brain, with the DBH inhibitors, etamicastat, nepicastat and zamicastat. Madin-Darby canine kidney cells (MDCK II) and transfected lines with human MDR1 (MDCK-MDR1) and ABCG2 (MDCK-BCRP) genes were used as a BBB surrogate model. P-gp and BCRP substrates and/or inhibitors were identified through intracellular accumulation and bidirectional permeability assays. The obtained data revealed that zamicastat is a concentration-dependent dual P-gp and BCRP inhibitor with IC 50 values of 73.8 ± 7.2 μM and 17.0 ± 2.7 μM, while etamicastat and nepicastat inhibited BCRP to greater extent than P-gp, with IC 50 values of 47.7 ± 1.8 μM and 59.2 ± 9.4 μM, respectively. Additionally, etamicastat was identified as P-gp and BCRP dual substrate, as demonstrated by net flux ratios of 5.84 and 3.87 and decreased >50% by verapamil and Ko143. Conversely, nepicastat revealed to be a P-gp-only substrate, with a net flux ratio of 2.01, reduced to 0.92 in the presence of verapamil. Furthermore, nepicastat displayed a consistently higher apparent permeability (>8.49 × 10 -6  cm s -1 ) than etamicastat (<0.58 × 10 -6  cm s -1 ). The identification of etamicastat as a dual efflux substrate suggests that P-gp and BCRP may be partially responsible for the limited central exposure of this compound, in association with its low passive permeability. Moreover, the weak efflux inhibitory potencies of etamicastat and nepicastat revealed a low DDI risk, while the dual P-gp/BCRP inhibition of zamicastat could be studied in the future with synergically effluxed compounds, for which BBB penetration is severely impaired. Copyright © 2018 Elsevier B.V. All rights reserved.

[AIDS: "We will win"].

PubMed

Chabrier, H

1989-11-13

An international colloquium on AIDS held near Paris from October 26-28, 1989, unlike the World Conference on AIDS in Montreal the year before, was able to find reasons for optimism. Significant progress was reported in immunotherapy and in chemotherapy. Successful experiments in vaccinating monkeys against the AIDS virus were reported from the US, France, and Zaire. Time is needed to prove the efficacy of the vaccines because of the slow development in AIDS. A vaccine is being tested by Jonas Salk and collaborators in 75 seropositive volunteers who do not yet show full blown disease but who have very low levels of T4 lymphocytes. Plans are underway for a larger test on 500 seropositive patients at different stages of infection. According to Salk, the new chemical and logical approach toward AIDS will allow combinations of immunotherapy and chemotherapy to destroy the virus. R. Gallo of France listed as accomplishments of the past year a better understanding of the virus, improved case management techniques, increased ability to control Kaposi's sarcoma, considerable progress in the search for a vaccine, and detection of immune proteins that affect the virus. New biological markers permit establishment of correlations between cellular modifications and the progress of the disease as well as the precise effects of treatment. The new immune system drugs immuthiol and DDI are expected to reach the market soon. Patients very soon will be able to receive less toxic alternative treatments, which can be combined for greater efficacy once their toxic interactions are understood.

A hybrid model based on neural networks for biomedical relation extraction.

PubMed

Zhang, Yijia; Lin, Hongfei; Yang, Zhihao; Wang, Jian; Zhang, Shaowu; Sun, Yuanyuan; Yang, Liang

2018-05-01

Biomedical relation extraction can automatically extract high-quality biomedical relations from biomedical texts, which is a vital step for the mining of biomedical knowledge hidden in the literature. Recurrent neural networks (RNNs) and convolutional neural networks (CNNs) are two major neural network models for biomedical relation extraction. Neural network-based methods for biomedical relation extraction typically focus on the sentence sequence and employ RNNs or CNNs to learn the latent features from sentence sequences separately. However, RNNs and CNNs have their own advantages for biomedical relation extraction. Combining RNNs and CNNs may improve biomedical relation extraction. In this paper, we present a hybrid model for the extraction of biomedical relations that combines RNNs and CNNs. First, the shortest dependency path (SDP) is generated based on the dependency graph of the candidate sentence. To make full use of the SDP, we divide the SDP into a dependency word sequence and a relation sequence. Then, RNNs and CNNs are employed to automatically learn the features from the sentence sequence and the dependency sequences, respectively. Finally, the output features of the RNNs and CNNs are combined to detect and extract biomedical relations. We evaluate our hybrid model using five public (protein-protein interaction) PPI corpora and a (drug-drug interaction) DDI corpus. The experimental results suggest that the advantages of RNNs and CNNs in biomedical relation extraction are complementary. Combining RNNs and CNNs can effectively boost biomedical relation extraction performance. Copyright © 2018 Elsevier Inc. All rights reserved.

Dietary β-conglycinin prevents fatty liver induced by a high-fat diet by a decrease in peroxisome proliferator-activated receptor γ2 protein.

PubMed

Yamazaki, Tomomi; Kishimoto, Kyoko; Miura, Shinji; Ezaki, Osamu

2012-02-01

Diets high in sucrose/fructose or fat can result in hepatic steatosis (fatty liver). Mice fed a high-fat diet, especially that of saturated-fat-rich oil, develop fatty liver with an increase in peroxisome proliferator-activated receptor (PPAR) γ2 protein in liver. The fatty liver induced by a high-fat diet is improved by knockdown of liver PPARγ2. In this study, we investigated whether β-conglycinin (a major protein of soy protein) could reduce PPARγ2 protein and prevent high-fat-diet-induced fatty liver in ddY mice. Mice were fed a high-starch diet (70 energy% [en%] starch) plus 20% (wt/wt) sucrose in their drinking water or a high-safflower-oil diet (60 en%) or a high-butter diet (60 en%) for 11 weeks, by which fatty liver is developed. As a control, mice were fed a high-starch diet with drinking water. Either β-conglycinin or casein (control) was given as dietary protein. β-Conglycinin supplementation completely prevented fatty liver induced by each type of diet, along with a reduction in adipose tissue weight. β-Conglycinin decreased sterol regulatory element-binding protein (SREBP)-1c and carbohydrate response element-binding protein (ChREBP) messenger RNAs (mRNAs) in sucrose-supplemented mice, whereas it decreased PPARγ2 mRNA (and its target genes CD36 and FSP27), but did not decrease SREBP-1c and ChREBP mRNAs, in mice fed a high-fat diet. β-Conglycinin decreased PPARγ2 protein and liver triglyceride (TG) concentration in a dose-dependent manner in mice fed a high-butter diet; a significant decrease in liver TG concentration was observed at a concentration of 15 en%. In conclusion, β-conglycinin effectively prevents fatty liver induced by a high-fat diet through a decrease in liver PPARγ2 protein. Copyright © 2012 Elsevier Inc. All rights reserved.

Sunitinib-ibuprofen drug interaction affects the pharmacokinetics and tissue distribution of sunitinib to brain, liver, and kidney in male and female mice differently.

PubMed

Lau, Christine Li Ling; Chan, Sook Tyng; Selvaratanam, Manimegahlai; Khoo, Hui Wen; Lim, Adeline Yi Ling; Modamio, Pilar; Mariño, Eduardo L; Segarra, Ignacio

2015-08-01

Tyrosine kinase inhibitor sunitinib (used in GIST, advanced RCC, and pancreatic neuroendocrine tumors) undergoes CYP3A4 metabolism and is an ABCB1B and ABCG2 efflux transporters substrate. We assessed the pharmacokinetic interaction with ibuprofen (an NSAID used by patients with cancer) in Balb/c male and female mice. Mice (study group) were coadministered (30 min apart) 30 mg/kg of ibuprofen and 60 mg/kg of sunitinib PO and compared with the control groups, which received sunitinib alone (60 mg/kg, PO). Sunitinib concentration in plasma, brain, kidney, and liver was measured by HPLC as scheduled and noncompartmental pharmacokinetic parameters estimated. In female control mice, sunitinib AUC0→∞ decreased in plasma (P < 0.05), was higher in liver and brain (P < 0.001), and lower in kidney (P < 0.001) vs. male control mice. After ibuprofen coadministration, female mice showed lower AUC0→∞ in plasma (P < 0.01), brain, liver, and kidney (all P < 0.001). However, in male mice, AUC0→∞ remained unchanged in plasma, increased in liver and kidney, and decreased in brain (all P < 0.001). The tissue-to-plasma AUC0→∞ ratio was similar between male and female control mice, but changed after ibuprofen coadministration: Male mice showed 1.6-fold higher liver-to-plasma ratio (P < 0.001) while remained unchanged in female mice and in kidney (male and female mice) but decreased 55% in brain (P < 0.05). The tissue-to-plasma partial AUC ratio, the drug tissue targeting index, and the tissue-plasma hysteresis-like plots also showed sex-based ibuprofen-sunitinib drug interaction differences. The results illustrate the relevance of this DDI on sunitinib pharmacokinetics and tissue uptake. These may be due to gender-based P450 and efflux/transporters differences. © 2015 Société Française de Pharmacologie et de Thérapeutique.

Oxidative Stress, DNA Damage and DNA Repair in Female Patients with Diabetes Mellitus Type 2

PubMed Central

Grindel, Annemarie; Guggenberger, Bianca; Eichberger, Lukas; Pöppelmeyer, Christina; Gschaider, Michaela; Tosevska, Anela; Mare, George; Briskey, David; Brath, Helmut; Wagner, Karl-Heinz

2016-01-01

Background Diabetes mellitus type 2 (T2DM) is associated with oxidative stress which in turn can lead to DNA damage. The aim of the present study was to analyze oxidative stress, DNA damage and DNA repair in regard to hyperglycemic state and diabetes duration. Methods Female T2DM patients (n = 146) were enrolled in the MIKRODIAB study and allocated in two groups regarding their glycated hemoglobin (HbA1c) level (HbA1c≤7.5%, n = 74; HbA1c>7.5%, n = 72). In addition, tertiles according to diabetes duration (DD) were created (DDI = 6.94±3.1 y, n = 49; DDII = 13.35±1.1 y, n = 48; DDIII = 22.90±7.3 y, n = 49). Oxidative stress parameters, including ferric reducing ability potential, malondialdehyde, oxidized and reduced glutathione, reduced thiols, oxidized LDL and F2-Isoprostane as well as the activity of antioxidant enzymes superoxide dismutase, catalase and glutathione peroxidase were measured. Damage to DNA was analyzed in peripheral blood mononuclear cells and whole blood with single cell gel electrophoresis. DNA base excision repair capacity was tested with the modified comet repair assay. Additionally, mRNA expressions of nine genes related to base excision repair were analyzed in a subset of 46 matched individuals. Results No significant differences in oxidative stress parameters, antioxidant enzyme activities, damage to DNA and base excision repair capacity, neither between a HbA1c cut off />7.5%, nor between diabetes duration was found. A significant up-regulation in mRNA expression was found for APEX1, LIG3 and XRCC1 in patients with >7.5% HbA1c. Additionally, we observed higher total cholesterol, LDL-cholesterol, LDL/HDL-cholesterol, triglycerides, Framingham risk score, systolic blood pressure, BMI and lower HDL-cholesterol in the hyperglycemic group. Conclusion BMI, blood pressure and blood lipid status were worse in hyperglycemic individuals. However, no major disparities regarding oxidative stress, damage to DNA and DNA repair were present which might be due to good medical treatment with regular health checks in T2DM patients in Austria. PMID:27598300

Superovulation Using the Combined Administration of Inhibin Antiserum and Equine Chorionic Gonadotropin Increases the Number of Ovulated Oocytes in C57BL/6 Female Mice

PubMed Central

Takeo, Toru; Nakagata, Naomi

2015-01-01

Superovulation is a reproductive technique generally used to produce genetically engineered mice. Superovulation in mice involves the administration of equine chorionic gonadotropin (eCG) to promote follicle growth and then that of human chorionic gonadotropin (hCG) to induce ovulation. Previously, some published studies reported that inhibin antiserum (IAS) increased the number of ovulated oocytes in ddY and wild-derived strains of mice. However, the effect of IAS on the C57BL/6 strain, which is the most widely used inbred strain for the production of genetically engineered mice, has not been investigated. In addition, the combined effect of IAS and eCG (IASe) on the number of ovulated oocytes in superovulation treatment has not been examined. In this study, we examined the effect of IAS and eCG on the number of ovulated oocytes in immature female mice of the C57BL/6 strain in superovulation treatment. Furthermore, we evaluated the quality of obtained oocytes produced by superovulation using IASe by in vitro fertilization (IVF) with sperm from C57BL/6 or genetically engineered mice. The developmental ability of fresh or cryopreserved embryos was examined by embryo transfer. The administration of IAS or eCG had a similar effect on the number of ovulated oocytes in C57BL/6 female mice. The number of ovulated oocytes increased to about 3-fold by the administration of IASe than by the administration of IAS or eCG alone. Oocytes derived from superovulation using IASe normally developed into 2-cell embryos by IVF using sperm from C57BL/6 mice. Fresh or cryopreserved 2-cell embryos produced by IVF between oocytes of C57BL/6 mice and sperm from genetically engineered mice normally developed into live pups following embryo transfer. In summary, a novel technique of superovulation using IASe is extremely useful for producing a great number of oocytes and offspring from genetically engineered mice. PMID:26024317

Oxidative Stress, DNA Damage and DNA Repair in Female Patients with Diabetes Mellitus Type 2.

PubMed

Grindel, Annemarie; Guggenberger, Bianca; Eichberger, Lukas; Pöppelmeyer, Christina; Gschaider, Michaela; Tosevska, Anela; Mare, George; Briskey, David; Brath, Helmut; Wagner, Karl-Heinz

2016-01-01

Diabetes mellitus type 2 (T2DM) is associated with oxidative stress which in turn can lead to DNA damage. The aim of the present study was to analyze oxidative stress, DNA damage and DNA repair in regard to hyperglycemic state and diabetes duration. Female T2DM patients (n = 146) were enrolled in the MIKRODIAB study and allocated in two groups regarding their glycated hemoglobin (HbA1c) level (HbA1c≤7.5%, n = 74; HbA1c>7.5%, n = 72). In addition, tertiles according to diabetes duration (DD) were created (DDI = 6.94±3.1 y, n = 49; DDII = 13.35±1.1 y, n = 48; DDIII = 22.90±7.3 y, n = 49). Oxidative stress parameters, including ferric reducing ability potential, malondialdehyde, oxidized and reduced glutathione, reduced thiols, oxidized LDL and F2-Isoprostane as well as the activity of antioxidant enzymes superoxide dismutase, catalase and glutathione peroxidase were measured. Damage to DNA was analyzed in peripheral blood mononuclear cells and whole blood with single cell gel electrophoresis. DNA base excision repair capacity was tested with the modified comet repair assay. Additionally, mRNA expressions of nine genes related to base excision repair were analyzed in a subset of 46 matched individuals. No significant differences in oxidative stress parameters, antioxidant enzyme activities, damage to DNA and base excision repair capacity, neither between a HbA1c cut off />7.5%, nor between diabetes duration was found. A significant up-regulation in mRNA expression was found for APEX1, LIG3 and XRCC1 in patients with >7.5% HbA1c. Additionally, we observed higher total cholesterol, LDL-cholesterol, LDL/HDL-cholesterol, triglycerides, Framingham risk score, systolic blood pressure, BMI and lower HDL-cholesterol in the hyperglycemic group. BMI, blood pressure and blood lipid status were worse in hyperglycemic individuals. However, no major disparities regarding oxidative stress, damage to DNA and DNA repair were present which might be due to good medical treatment with regular health checks in T2DM patients in Austria.

Simultaneous determination of erlotinib and tamoxifen in rat plasma using UPLC-MS/MS: Application to pharmacokinetic interaction studies.

PubMed

Maher, Hadir M; Alzoman, Nourah Z; Shehata, Shereen M

2016-08-15

Tamoxifen (TAM) is a non-steroidal estrogen receptor antagonist that enhances erlotinib (ERL)-induced cytotoxicity in the treatment of NSCLC. ERL and TAM are metabolized by CYP3A4 enzymes. In addition, both drugs have the potential of altering the enzymatic activity through either inhibition (ERL) or induction (TAM). Thus it was expected that pharmacokinetics (PK) drug-drug interactions (DDIs) could be encountered following their co-administration. In this respect, a bioanalytical UPLC-MS/MS method has been developed and validated for the simultaneous determination of ERL and TAM in rat plasma samples, using ondansetron (OND) as an internal standard (IS). Plasma samples were prepared using mixed mode cationic solid phase extraction (SPE) STRATA™ -X-C 33μm cartridges with good extraction recovery of both drugs from rat plasma (Er% from -13.92 to -3.32). The drugs were separated on a Waters BEH™ C18 column with an isocratic elution using a mobile phase composed of a mixture of acetonitrile and water, each with 0.15% formic acid, in the ratio of 80: 20, v/v. Quantitation was carried out using the positive ionization mode with multiple reaction monitoring (MRM) at m/z 394.20>278.04 (ERL), m/z 372.25>72.01 (TAM), and m/z 294.18>170.16 (OND). The method was fully validated as per the FDA guidelines over the concentration range of 0.2-50ng/mL with very low lower limit of quantification (LLOQ) of 0.2ng/mL for both ERL and TAM. The intra- and inter-day assay precision (in terms of relative standard deviation, RSD) and accuracy (in terms of percentage relative error, % Er) were evaluated for both drugs and the calculated values evaluated at four different concentration levels were within the acceptable limits (<15%) for concentrations other than LLOQ and 20% for LLOQ. The method was successfully applied to the study of possible PK-DDI following the oral administration of ERL and TAM in a combination, compared to their single administration. Copyright © 2016 Elsevier B.V. All rights reserved.

Epidemiology of Drug-Disease Interactions in Older Veteran Nursing Home Residents

PubMed Central

Aspinall, Sherrie L.; Zhao, Xinhua; Semla, Todd P.; Cunningham, Francesca E.; Paquin, Allison M.; Pugh, Mary Jo; Schmader, Kenneth E.; Stone, Roslyn A.; Hanlon, Joseph T.

2014-01-01

Objectives Few studies have examined drug-disease interactions (DDIs) in older nursing home residents. Therefore, the objective is to describe the prevalence of, and factors associated with, DDIs according to The American Geriatrics Society 2012 Beers Criteria. Design Cross-sectional study. Setting Fifteen Veterans Affairs Community Living Centers. Participants Patients≥65 years old with a diagnosis of dementia/cognitive impairment, history of falls/hip fractures, heart failure (HF), history of peptic ulcer disease (PUD) and/or stage IV or V chronic kidney disease (CKD). Measurements Prevalence of medications that could exacerbate the above conditions (i.e., DDIs). Results Overall, 361 of 696 (51.9%) eligible residents had ≥1 DDI. None involved those with a history of PUD; one involved a resident with CKD, and four occurred in those with HF. In residents with dementia/cognitive impairment (N=540), 50.7% took a drug that could exacerbate these conditions; the most commonly involved medications were antipsychotics (35.4%) and benzodiazepines (14.4%). In those with a history of falls/hip fractures (N=267), 67.8% received an interacting medication, with SSRIs (33.1%), antipsychotics (30.7%) and anticonvulsants (25.1%) being most commonly involved. Using separate multivariable logistic regression models, factors associated with DDIs in both dementia/cognitive impairment and falls/fractures included: age 85+ (Adjusted Odds Ratio [aOR] and 95% confidence interval [CI] of 0.38; 0.24–0.60 and aOR 0.48; 95%CI 0.24–0.96, respectively); taking 5–8 medications (aOR 2.06; 95%CI 1.02–4.16 and aOR 4.76; 95%CI 1.68–13.5, respectively) and ≥9 medications (aOR 1.99; 95%CI 1.03–3.85 and aOR 3.68; 95%CI 1.41–9.61, respectively), and being a long stay patient (aOR 1.80; 95%CI 1.04–3.12 and aOR 2.35; 95%CI 1.12–4.91, respectively). Conclusion Drug-disease interactions were common in older nursing home residents with dementia/cognitive impairment and/or a history of falls/fractures. PMID:25537124

Variations of L- and D-amino acid levels in the brain of wild-type and mutant mice lacking D-amino acid oxidase activity.

PubMed

Du, Siqi; Wang, Yadi; Weatherly, Choyce A; Holden, Kylie; Armstrong, Daniel W

2018-05-01

D-amino acids are now recognized to be widely present in organisms and play essential roles in biological processes. Some D-amino acids are metabolized by D-amino acid oxidase (DAO), while D-Asp and D-Glu are metabolized by D-aspartate oxidase (DDO). In this study, levels of 22 amino acids and the enantiomeric compositions of the 19 chiral proteogenic entities have been determined in the whole brain of wild-type ddY mice (ddY/DAO +/+ ), mutant mice lacking DAO activity (ddY/DAO -/- ), and the heterozygous mice (ddY/DAO +/- ) using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). No significant differences were observed for L-amino acid levels among the three strains except for L-Trp which was markedly elevated in the DAO +/- and DAO -/- mice. The question arises as to whether this is an unknown effect of DAO inactivity. The three highest levels of L-amino acids were L-Glu, L-Asp, and L-Gln in all the three strains. The lowest L-amino acid level was L-Cys in ddY/DAO +/- and ddY/DAO -/- mice, while L-Trp showed the lowest level in ddY/DAO +/+ mice. The highest concentration of D-amino acid was found to be D-Ser, which also had the highest % D value (~ 25%). D-Glu had the lowest % D value (~ 0.01%) in all the three strains. Significant differences of D-Leu, D-Ala, D-Ser, D-Arg, and D-Ile were observed in ddY/DAO +/- and ddY/DAO -/- mice compared to ddY/DAO +/+ mice. This work provides the most complete baseline analysis of L- and D-amino acids in the brains of ddY/DAO +/+ , ddY/DAO +/- , and ddY/DAO -/- mice yet reported. It also provides the most effective and efficient analytical approach for measuring these analytes in biological samples. This study provides fundamental information on the role of DAO in the brain and may be relevant for future development involving novel drugs for DAO regulation.

Intracerebral Inoculation of Mouse-Passaged Saffold Virus Type 3 Affects Cerebellar Development in Neonatal Mice

PubMed Central

Kotani, Osamu; Suzuki, Tadaki; Yokoyama, Masaru; Iwata-Yoshikawa, Naoko; Nakajima, Noriko; Sato, Hironori; Hasegawa, Hideki; Taguchi, Fumihiro; Shimizu, Hiroyuki

2016-01-01

ABSTRACT Saffold virus (SAFV), a human cardiovirus, is occasionally detected in infants with neurological disorders, including meningitis and cerebellitis. We recently reported that SAFV type 3 isolates infect cerebellar glial cells, but not large neurons, in mice. However, the impact of this infection remained unclear. Here, we determined the neuropathogenesis of SAFV type 3 in the cerebella of neonatal ddY mice by using SAFV passaged in the cerebella of neonatal BALB/c mice. The virus titer in the cerebellum increased following the inoculation of each of five passaged strains. The fifth passaged strain harbored amino acid substitutions in the VP2 (H160R and Q239R) and VP3 (K62M) capsid proteins. Molecular modeling of the capsid proteins suggested that the VP2-H160R and VP3-K62M mutations alter the structural dynamics of the receptor binding surface via the formation of a novel hydrophobic interaction between the VP2 puff B and VP3 knob regions. Compared with the original strain, the passaged strain showed altered growth characteristics in human-derived astroglial cell lines and greater replication in the brains of neonatal mice. In addition, the passaged strain was more neurovirulent than the original strain, while both strains infected astroglial and neural progenitor cells in the mouse brain. Intracerebral inoculation of either the original or the passaged strain affected brain Purkinje cell dendrites, and a high titer of the passaged strain induced cerebellar hypoplasia in neonatal mice. Thus, infection by mouse-passaged SAFV affected cerebellar development in neonatal mice. This animal model contributes to the understanding of the neuropathogenicity of SAFV infections in infants. IMPORTANCE Saffold virus (SAFV) is a candidate neuropathogenic agent in infants and children, but the neuropathogenicity of the virus has not been fully elucidated. Recently, we evaluated the pathogenicity of two clinical SAFV isolates in mice. Similar to other neurotropic picornaviruses, these isolates showed mild infectivity of glial and neural progenitor cells, but not of large neurons, in the cerebellum. However, the outcome of this viral infection in the cerebellum has not been clarified. Here, we examined the tropism of SAFV in the cerebellum. We obtained an in vivo-passaged strain from the cerebella of neonatal mice and examined its genome and its neurovirulence in the neonatal mouse brain. The passaged virus showed high infectivity and neurovirulence in the brain, especially the cerebellum, and affected cerebellar development. This unique neonatal mouse model will be helpful for elucidating the neuropathogenesis of SAFV infections occurring early in life. PMID:27581974

Proceedings of the 2013 Joint JSTP/NTP Satellite Symposium

PubMed Central

Elmore, Susan A.; Hoenerhoff, Mark; Katsuta, Osamu; Kokoshima, Hiroko; Maronpot, Robert; Nagai, Hiroaki; Satoh, Hiroshi; Tanaka, Yasuhiro; Tochitani, Tomoaki; Tsuchiya, Seiichiro; Yoshizawa, Katsuhiko

2013-01-01

The first joint Japanese Society of Toxicologic Pathology (JSTP) and National Toxicology Program (NTP) Satellite Symposium, entitled “Pathology Potpourri,” was held on January 29th at Okura Frontier Hotel in Tsukuba, Ibaraki, Japan, in advance of the JSTP’s 29th Annual Meeting. The goal of this Symposium was to present current diagnostic pathology or nomenclature issues to the toxicologic pathology community. This article presents summaries of the speakers’ presentations, including diagnostic or nomenclature issues that were presented, select images that were used for audience voting or discussion, and the voting results. Some lesions and topics covered during the symposium include: treatment-related atypical hepatocellular foci of cellular alteration in B6C3F1 mice; purulent ventriculoencephalitis in a young BALB/c mouse; a subcutaneous malignant schwannoma in a RccHan:WIST rat; spontaneous nasal septum hyalinosis/eosinophilic substance in B6C3F1 mice; a rare pancreatic ductal cell adenoma in a young Lewis rat; eosinophilic crystalline pneumonia in a transgenic mouse model; hyaline glomerulopathy in two female ddY mice; treatment-related intrahepatic erythrocytes in B6C3F1 mice; treatment-related subendothelial hepatocytes in B6C3F1 mice; spontaneous thyroid follicular cell vacuolar degeneration in a cynomolgus monkey; congenital hepatic fibrosis in a 1-year-old cat; a spontaneous adenocarcinoma of the middle ear in a young Crl:CD(SD) rat; and finally a series of cases illustrating some differences between cholangiofibrosis and cholangiocarcinoma in Sprague Dawley and F344 rats. PMID:23914068

QSAR Modeling and Prediction of Drug-Drug Interactions.

PubMed

Zakharov, Alexey V; Varlamova, Ekaterina V; Lagunin, Alexey A; Dmitriev, Alexander V; Muratov, Eugene N; Fourches, Denis; Kuz'min, Victor E; Poroikov, Vladimir V; Tropsha, Alexander; Nicklaus, Marc C

2016-02-01

Severe adverse drug reactions (ADRs) are the fourth leading cause of fatality in the U.S. with more than 100,000 deaths per year. As up to 30% of all ADRs are believed to be caused by drug-drug interactions (DDIs), typically mediated by cytochrome P450s, possibilities to predict DDIs from existing knowledge are important. We collected data from public sources on 1485, 2628, 4371, and 27,966 possible DDIs mediated by four cytochrome P450 isoforms 1A2, 2C9, 2D6, and 3A4 for 55, 73, 94, and 237 drugs, respectively. For each of these data sets, we developed and validated QSAR models for the prediction of DDIs. As a unique feature of our approach, the interacting drug pairs were represented as binary chemical mixtures in a 1:1 ratio. We used two types of chemical descriptors: quantitative neighborhoods of atoms (QNA) and simplex descriptors. Radial basis functions with self-consistent regression (RBF-SCR) and random forest (RF) were utilized to build QSAR models predicting the likelihood of DDIs for any pair of drug molecules. Our models showed balanced accuracy of 72-79% for the external test sets with a coverage of 81.36-100% when a conservative threshold for the model's applicability domain was applied. We generated virtually all possible binary combinations of marketed drugs and employed our models to identify drug pairs predicted to be instances of DDI. More than 4500 of these predicted DDIs that were not found in our training sets were confirmed by data from the DrugBank database.

Unique action mechanisms of tramadol in global cerebral ischemia-induced mechanical allodynia.

PubMed

Matsuura, Wataru; Kageyama, Erika; Harada, Shinichi; Tokuyama, Shogo

2016-06-15

Central poststroke pain is associated with specific somatosensory abnormalities, such as neuropathic pain syndrome. Although central poststroke pain is a serious condition, details pertaining to underlying mechanisms are not well established, making current standard treatments only partially effective. Here, we assessed the effects of tramadol, an analgesic drug mediated by opioid receptors, using a mouse model of global cerebral ischemia. Ischemia was induced by bilateral carotid artery occlusion (30 min) in male ddY mice. Development of hind-paw mechanical allodynia was measured 3 days after bilateral carotid artery occlusion using the von Frey test. Mechanical allodynia was significantly and dose dependently suppressed by intraperitoneal tramadol (10 or 20 mg/kg). These effects, which peaked at 10 min and continued for at least 60 min, were inhibited by naloxone (nonselective opioid receptor antagonist, 1 mg/kg, intraperitoneal). Tramadol antinociception was significantly negated by β-funaltrexamine (selective μ-opioid receptor antagonist, 20 mg/kg, intraperitoneal), but not naltrindole (selective δ-opioid receptor antagonist, 5 mg/kg, intraperitoneal) or nor-binaltorphimine (selective κ-opioid receptor antagonist, 10 mg/kg, intraperitoneal) after 5 min, by β-funaltrexamine and nor-binaltorphimine but not naltrindole after 10 min, and by all selective opioid receptor antagonists at 15 and 30 min after tramadol treatment. These results suggested that antinociception induced by tramadol through various opioid receptors was time dependent. Furthermore, it is possible that the opioid receptors involved in tramadol-induced antinociception change over time with the metabolism of this drug.

Administration of bovine casein-derived peptide prevents cognitive decline in Alzheimer disease model mice.

PubMed

Min, Li-Juan; Kobayashi, Yodai; Mogi, Masaki; Tsukuda, Kana; Yamada, Akio; Yamauchi, Koji; Abe, Fumiaki; Iwanami, Jun; Xiao, Jin-Zhong; Horiuchi, Masatsugu

2017-01-01

There is a growing interest in identifying natural food ingredients that may serve to prevent dementia such as that due to Alzheimer disease (AD). Peptides derived from food proteins have been demonstrated to have various physiological activities such as a hypotensive action. Recent findings have indicated possible associations of hypertension with AD progression, and suggest that angiotensin converting enzyme (ACE) inhibitors with potential to pass through the blood brain barrier (BBB) may reduce the risk of AD. In this study, we investigated the effect of milk peptide (CH-3) on cognitive function in AD model mice. CH-3 contains a tripeptide (methionine-lysine-proline, MKP) that has been found to have a strong ACE inhibitory effect and the potential to pass through the BBB. Adult male ddY mice were used in this study, and an animal model of AD was induced by intracerebroventricular (ICV) injection of Aβ1-42. CH-3 (250 mg/kg/day) or MKP (0.5 mg/kg/day) was orally administered every day starting 2 days before ICV injection. At 3 weeks after ICV injection, cognitive function was evaluated by the Morris water maze test. Brain samples were obtained after behavioral testing, and expression of inflammatory cytokines and NADPH oxidase subunits was measured by real-time quantitative RT-PCR. ICV injection of Aβ1-42 significantly impaired cognitive function compared with that in PBS-injected mice. Daily administration of CH-3 markedly attenuated this Aβ1-42-induced cognitive decline. Aβ1-42 injection significantly enhanced the expression of tumor necrosis factor-α (TNF-α), inducible nitric oxide synthase (iNOS) and p22phox in the mouse hippocampus compared with PBS injection, and showed a tendency to increase the expression of monocyte chemoattractant protein-1 (MCP-1), p47phox and gp91phox, whereas CH-3 treatment markedly reduced Aβ1-42-induced TNF-α, MCP-1, iNOS, p47phox and gp91phox expression. Finally, administration of MKP also attenuated Aβ1-42-induced cognitive impairment with an increase in cerebral blood flow. The present study demonstrated that repeated oral administration of CH-3 to AD model mice not only improved cognitive function but also suppressed the expression of inflammatory cytokines and production of oxidative stress, and suggests its therapeutic potential for preventing cognitive impairment in AD.

The impact of polypharmacy and drug interactions among the elderly population in Western Sicily, Italy.

PubMed

Scondotto, Giulia; Pojero, Fanny; Pollina Addario, Sebastiano; Ferrante, Mauro; Pastorello, Maurizio; Visconti, Michele; Scondotto, Salvatore; Casuccio, Alessandra

2018-01-01

Primary endpoint was to report polypharmacy distribution in the general population vs ≥65 years old people and to examine the frequency of drug-drug interactions (DDIs) in the Health Local Unit of Palermo, Italy, in relationship with patients' age. Drug prescription data for the year 2014 were extracted from the database of the Local Health Unit of Palermo Province, Italy. Patients were divided into five age groups (0-13, 14-64, 65-69, 70-74, and ≥75 year old). The detection of potential DDIs in polypharmacy profiles was performed with NavFarma software (Infologic srl, Padova, Italia), with DDI classification provided by tool Micromedex Drug Reax (Truven Health Analitics, Michigan, USA). We analyzed data of 1,324,641 patients, and 15,801,191 medical prescription were recorded; of these, 11,337,796 regarded chronic conditions. The drug prescriptions reached the highest values in the 65-69 and 70-74 age groups (p = 0.005 and p = 0.008 vs age 14-64 respectively). An overall amount of 6,094,373 DDIs were detected, of which 47,173 were contraindicated. Median number of DDIs was higher in 65-69 and 70-74 age groups (p = 0.008 and p = 0.012 vs age 14-64, respectively). Regarding contraindicated DDIs a significant difference was detected comparing 14-64 vs ≥65 age groups (p = 0.010 vs 65-69 group, p = 0.005 vs 70-74 group and ≥75 group). Polypharmacy is a phenomenon acquiring increasing dimensions also in our province. It interests particularly the older subjects, and assumes a dramatic accent when it is put in relationship with the frequency of DDIs. A proactive vigilance about potential life threatening drug interactions is mandatory.

Neonatal monosodium glutamate treatment causes obesity, diabetes, and macrovesicular steatohepatitis with liver nodules in DIAR mice.

PubMed

Tsuneyama, Koichi; Nishida, Takeshi; Baba, Hayato; Taira, Shu; Fujimoto, Makoto; Nomoto, Kazuhiro; Hayashi, Shinichi; Miwa, Shigeharu; Nakajima, Takahiko; Sutoh, Mitsuko; Oda, Emu; Hokao, Ryoji; Imura, Johji

2014-09-01

Non-alcoholic steatohepatitis (NASH) is the hepatic manifestation of metabolic syndrome (MS). Monosodium glutamate (MSG)-treated ICR mice is a useful model of MS and NASH, but it shows the different patterns of steatosis from human NASH. Because inbred aged DIAR (ddY, Institute for Animal Reproduction) mice spontaneously show the similar pattern of steatosis as NASH, we analyzed their liver pathology after administering MSG. MSG-treated DIAR mice (DIAR-MSG) and untreated DIAR mice (DIAR-controls) were sacrificed and assessed histopathologically at 29, 32, 40, 48, and 54 weeks of age. The NASH activity score, body mass index, blood glucose level, and oral glucose tolerance test were also assessed. The body mass index and blood glucose levels of DIAR-MSG were significantly higher than controls. The oral glucose tolerance test revealed a type 2 diabetes pattern in DIAR-MSG. The livers of DIAR-MSG mice showed macrovesicular steatosis, lobular inflammation with neutrophils, and ballooning degeneration after 29 weeks. At 54 weeks, mild fibrosis was observed in 5/6 DIAR-MSG and 2/5 DIAR-control mice. In imaging mass spectrometry analysis, cholesterol as well as triglyceride accumulated in the liver of DIAR-MSG mice. Atypical liver nodules were also observed after 32 weeks in DIAR-MSG, some with cellular and structural atypia mimicking human hepatocellular carcinoma. The NASH activity score of DIAR-MSG after 29 weeks was higher than that of control mice, suggesting the development of NASH. DIAR-MSG had NASH-like liver pathology and liver nodules typically associated with MS symptoms. DIAR-MSG provides a valuable animal model to analyze NASH pathogenesis and carcinogenesis. © 2014 Journal of Gastroenterology and Hepatology Foundation and Wiley Publishing Asia Pty Ltd.

Guanine nucleotide-binding protein (Gα) endocytosis by a cascade of ubiquitin binding domain proteins is required for sustained morphogenesis and proper mating in yeast.

PubMed

Dixit, Gauri; Baker, Rachael; Sacks, Carly M; Torres, Matthew P; Dohlman, Henrik G

2014-05-23

Heterotrimeric G proteins are well known to transmit signals from cell surface receptors to intracellular effector proteins. There is growing appreciation that G proteins are also present at endomembrane compartments, where they can potentially interact with a distinct set of signaling proteins. Here, we examine the cellular trafficking function of the G protein α subunit in yeast, Gpa1. Gpa1 contains a unique 109-amino acid insert within the α-helical domain that undergoes a variety of posttranslational modifications. Among these is monoubiquitination, catalyzed by the NEDD4 family ubiquitin ligase Rsp5. Using a newly optimized method for G protein purification together with biophysical measures of structure and function, we show that the ubiquitination domain does not influence enzyme activity. By screening a panel of 39 gene deletion mutants, each lacking a different ubiquitin binding domain protein, we identify seven that are necessary to deliver Gpa1 to the vacuole compartment including four proteins (Ede1, Bul1, Ddi1, and Rup1) previously not known to be involved in this process. Finally, we show that proper endocytosis of the G protein is needed for sustained cellular morphogenesis and mating in response to pheromone stimulation. We conclude that a cascade of ubiquitin-binding proteins serves to deliver the G protein to its final destination within the cell. In this instance and in contrast to the previously characterized visual system, endocytosis from the plasma membrane is needed for proper signal transduction rather than for signal desensitization. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

2'-Deoxyribosyltransferase from Leishmania mexicana, an efficient biocatalyst for one-pot, one-step synthesis of nucleosides from poorly soluble purine bases.

PubMed

Crespo, N; Sánchez-Murcia, P A; Gago, F; Cejudo-Sanches, J; Galmes, M A; Fernández-Lucas, Jesús; Mancheño, José Miguel

2017-10-01

Processes catalyzed by enzymes offer numerous advantages over chemical methods although in many occasions the stability of the biocatalysts becomes a serious concern. Traditionally, synthesis of nucleosides using poorly water-soluble purine bases, such as guanine, xanthine, or hypoxanthine, requires alkaline pH and/or high temperatures in order to solubilize the substrate. In this work, we demonstrate that the 2'-deoxyribosyltransferase from Leishmania mexicana (LmPDT) exhibits an unusually high activity and stability under alkaline conditions (pH 8-10) across a broad range of temperatures (30-70 °C) and ionic strengths (0-500 mM NaCl). Conversely, analysis of the crystal structure of LmPDT together with comparisons with hexameric, bacterial homologues revealed the importance of the relationships between the oligomeric state and the active site architecture within this family of enzymes. Moreover, molecular dynamics and docking approaches provided structural insights into the substrate-binding mode. Biochemical characterization of LmPDT identifies the enzyme as a type I NDT (PDT), exhibiting excellent activity, with specific activity values 100- and 4000-fold higher than the ones reported for other PDTs. Interestingly, LmPDT remained stable during 36 h at different pH values at 40 °C. In order to explore the potential of LmPDT as an industrial biocatalyst, enzymatic production of several natural and non-natural therapeutic nucleosides, such as vidarabine (ara A), didanosine (ddI), ddG, or 2'-fluoro-2'-deoxyguanosine, was carried out using poorly water-soluble purines. Noteworthy, this is the first time that the enzymatic synthesis of 2'-fluoro-2'-deoxyguanosine, ara G, and ara H by a 2'-deoxyribosyltransferase is reported.

Using structural knowledge in the protein data bank to inform the search for potential host-microbe protein interactions in sequence space: application to Mycobacterium tuberculosis.

PubMed

Mahajan, Gaurang; Mande, Shekhar C

2017-04-04

A comprehensive map of the human-M. tuberculosis (MTB) protein interactome would help fill the gaps in our understanding of the disease, and computational prediction can aid and complement experimental studies towards this end. Several sequence-based in silico approaches tap the existing data on experimentally validated protein-protein interactions (PPIs); these PPIs serve as templates from which novel interactions between pathogen and host are inferred. Such comparative approaches typically make use of local sequence alignment, which, in the absence of structural details about the interfaces mediating the template interactions, could lead to incorrect inferences, particularly when multi-domain proteins are involved. We propose leveraging the domain-domain interaction (DDI) information in PDB complexes to score and prioritize candidate PPIs between host and pathogen proteomes based on targeted sequence-level comparisons. Our method picks out a small set of human-MTB protein pairs as candidates for physical interactions, and the use of functional meta-data suggests that some of them could contribute to the in vivo molecular cross-talk between pathogen and host that regulates the course of the infection. Further, we present numerical data for Pfam domain families that highlights interaction specificity on the domain level. Not every instance of a pair of domains, for which interaction evidence has been found in a few instances (i.e. structures), is likely to functionally interact. Our sorting approach scores candidates according to how "distant" they are in sequence space from known examples of DDIs (templates). Thus, it provides a natural way to deal with the heterogeneity in domain-level interactions. Our method represents a more informed application of local alignment to the sequence-based search for potential human-microbial interactions that uses available PPI data as a prior. Our approach is somewhat limited in its sensitivity by the restricted size and diversity of the template dataset, but, given the rapid accumulation of solved protein complex structures, its scope and utility are expected to keep steadily improving.

Comparison of sucrose and trehalose media modification as an update of oocyte vitrification: A study of apoptotic level

NASA Astrophysics Data System (ADS)

Lestari, Silvia W.; Fitriyah, Nurin N.; Pangestu, Mulyoto; Pratama, Gita; Margiana, Ria

2018-02-01

Number of women who are not being able to have offspring in their reproductive life is increasing which might be influenced by several factors. As a consequence, oocyte cryopreservation could be an ensuring solution for women fertility preservation. A good vitrification could be conducted by combining an appropriate of type and concentration of cryoprotectants. One of the marks of successful vitrification is the vitrified oocytes could avoid apoptosis. This study aimed to evaluate the modification of cryoprotectant media as un update of oocyte vitrification as follow: the combination and the concentration of cryoprotectant media of oocytes vitrification, based on their effects on the apoptosis or DNA damage of oocytes. A total of 84 MII stage oocytes from adult female Deutschland, Denken and Yoken (DDY) mice (7-8 weeks old) were used in this study. Vitrification procedure was performed by using VS1 contained 15% EG, 15% DMSO, 0.5 mol/l sucrose (Merck, Darmstadt, Germany) and VS2 contained 15% EG, 15% DMSO, 0.5 mol/l trehalose (Merck, Darmstadt, Germany) in HM. Furthermore, warming solution (WS) was divided into four groups. There were: WS1a contained 0.3 mol/l sucrose, WS1b contained 0.15 mol/l sucrose, WS2a contained 0.3 mol/l trehalose, and WS2b contained 0.15 mol/l trehalose. Apoptotic level was performed by staining the oocytes with TUNEL and propidium iodide (PI) based on Brison and Schultz method then examined under confocal microscope. The rate of apoptosis in oocytes after vitrification and warming was higher compared to the fresh control oocytes. Furthermore, the rate of apoptosis in the vitrified oocytes by sucrose media (28%) was higher compared to the vitrified oocytes by trehalose media (16%). The results of this study indicated that vitrification increased apoptosis in the vitrified oocytes related to the oocyte injury after vitrification. Moreover, the vitrification increased apoptosis more in the vitrified oocytes by sucrose media than the vitrified oocytes by trehalose media. The exposure to the 16.5% EG, 16.5% DMSO and 0.5 mol/l trehalose as cryoprotectant media decreased their viability and increased the number of DNA-fragmented nuclei in the oocytes, lesser than sucrose. Trehalose was proved to be the more suitable extracellular cryoprotectant media in oocyte vitrification based on the apoptotic level, compared to that of sucrose. A modification of cryoprotectant media as an update of oocyte vitrification consisted 0.5 mol/l trehalose concentration as extracellular cryoprotectant and combined with 16.5% EG and 16.5% DMSO as intracellular cryoprotectant has produced.

Impact of Multiple Pharmacy Use on Medication Adherence and Drug-drug Interactions in Older Adults with Medicare Part D

PubMed Central

Marcum, Zachary A.; Driessen, Julia; Thorpe, Carolyn T.; Gellad, Walid F.; Donohue, Julie M.

2014-01-01

Objective To assess the association between multiple pharmacy use and medication adherence and potential drug-drug interactions (DDIs) among older adults. Design, Setting, and Participants Cross-sectional propensity score-weighted analysis of 2009 claims data from a nationally representative sample of 926,956 Medicare Part D beneficiaries aged >65 continuously enrolled in fee-for-service Medicare and Part D that year, and filled >1 prescription at a community/retail or mail order pharmacy. Multiple pharmacy use was defined as concurrent (overlapping time periods) or sequential use (non-overlapping time periods) of >2 pharmacies in the year. Measurements Medication adherence was calculated using a proportion of days covered ≥0.80 for eight therapeutic categories (β-blockers, renin angiotensin system antagonists, calcium channel blockers, statins, sulfonylureas, biguanides [i.e., metformin], thiazolidinediones, and dipeptidyl peptidase-IV inhibitors). Potential DDIs arising from use of certain drugs across a broad set of classes were defined as the concurrent filling of two interacting drugs. Results Overall, 38.1% of the sample used multiple pharmacies. Those using multiple pharmacies (both concurrently and sequentially) consistently had higher adjusted odds of non-adherence (ranging from 1.10 to 1.31, p<0.001) across all chronic medication classes assessed after controlling for socio-demographic, health status and access to care factors, compared to single pharmacy users. The adjusted predicted probability of exposure to a DDI was also slightly higher for those using multiple pharmacies concurrently (3.6%) compared to single pharmacy users (3.2%, AOR 1.11, 95% CI 1.08–1.15) but lower in individuals using multiple pharmacies sequentially (2.8%, AOR 0.85, 95% CI 0.81–0.91). Conclusions Filling prescriptions at multiple pharmacies was associated with lower medication adherence across multiple chronic medications, and a small but statistically significant increase in DDIs among concurrent pharmacy users. PMID:24521363

Characterization of a Multimodular Endo-β-1,4-Glucanase (Cel9K) from Paenibacillus sp. X4 with a Potential Additive for Saccharification.

PubMed

Lee, Jae Pil; Kim, Yoon A; Kim, Sung Kyum; Kim, Hoon

2018-04-28

An endo-β-1,4-glucanase gene, cel 9K, was cloned using the shot-gun method from Paenibacillus sp. X4, which was isolated from alpine soil. The gene was 2,994 bp in length, encoding a protein of 997 amino acid residues with a predicted signal peptide composed of 32 amino acid residues. Cel9K was a multimodular enzyme, and the molecular mass and theoretical pI of the mature Cel9K were 103.5 kDa and 4.81, respectively. Cel9K contains the GGxxDAGD, PHHR, GAxxGG, YxDDI, and EVxxDYN motifs found in most glycoside hydrolase family 9 (GH9). The protein sequence showed the highest similarity (88%) with the cellulase of Bacillus sp. BP23 in comparison to the enzymes with reported properties. The enzyme was purified by chromatography using HiTrap Q, CHT-II, and HiTrap Butyl HP. Using SDS-PAGE/activity staining, the molecular mass of Cel9K was estimated to be 93 kDa, which is a truncated form produced by the proteolytic cleavage of its C-terminus. Cel9K was optimally active at pH 5.5 and 50°C and showed a half-life of 59.2 min at 50°C. The CMCase activity was increased to more than 150% in the presence of 2 mM Na⁺, K⁺, and Ba²⁺, but decreased significantly to less than 50% by Mn²⁺ and Co²⁺. The addition of Cel9K to a commercial enzyme set (Celluclast 1.5L + Novozym 188) increased the saccharification of the pretreated reed and rice straw powders by 30.4 and 15.9%, respectively. The results suggest that Cel9K can be used to enhance the enzymatic conversion of lignocellulosic biomass to reducing sugars as an additive.

Cell cultures in drug discovery and development: The need of reliable in vitro-in vivo extrapolation for pharmacodynamics and pharmacokinetics assessment.

PubMed

Jaroch, Karol; Jaroch, Alina; Bojko, Barbara

2018-01-05

For ethical and cost-related reasons, use of animals for the assessment of mode of action, metabolism and/or toxicity of new drug candidates has been increasingly scrutinized in research and industrial applications. Implementation of the 3 "Rs" 1 ; rule (Reduction, Replacement, Refinement) through development of in silico or in vitro assays has become an essential element of risk assessment. Physiologically based pharmacokinetic (PBPK 2 ) modeling is the most potent in silico tool used for extrapolation of pharmacokinetic parameters to animal or human models from results obtained in vitro. Although, many types of in vitro assays are conducted during drug development, use of cell cultures is the most reliable one. Two-dimensional (2D) cell cultures have been a part of drug development for many years. Nowadays, their role is decreasing in favor of three-dimensional (3D) cell cultures and co-cultures. 3D cultures exhibit protein expression patterns and intercellular junctions that are closer to in vivo states in comparison to classical monolayer cultures. Co-cultures allow for examinations of the mutual influence of different cell lines. However, the complexity and high costs of co-cultures and 3D equipment exclude such methods from high-throughput screening (HTS). 3 In vitro absorption, distribution, metabolism, and excretion assessment, as well as drug-drug interaction (DDI), are usually performed with the use of various cell culture based assays. Progress in in silico and in vitro methods can lead to better in vitro-in vivo extrapolation (IVIVE 4 ) outcomes and have a potential to contribute towards a significant reduction in the number of laboratory animals needed for drug research. As such, concentrated efforts need to be spent towards the development of an HTS in vitro platform with satisfactory IVIVE features. Copyright © 2017 Elsevier B.V. All rights reserved.

Toxicity Assessment of the Xanthid Crab Demania cultripes from Cebu Island, Philippines

PubMed Central

Asakawa, Manabu; Gomez-Delan, Gloria; Tsuruda, Shintaro; Shimomura, Michitaka; Shida, Yasuo; Taniyama, Shigeto; Barte-Quilantang, Mercy; Shindo, Jo

2010-01-01

Several cases of poisoning resulting in human fatalities and stemming from the ingestion of coral reef crabs have been reported from the Indo-Pacific region. We assessed the toxicity of the unidentified xanthid crab collected from the Camotes Sea off the eastern coast of Cebu Island, central Visayas region of Philippines from the food hygienic point of view. All seven specimens, which were identified with Demania cultripes, collected in 2006 were toxic to mice irrespective of the season of collection and induced paralytic symptoms typical of tetrodotoxin (TTX) and paralytic shellfish poison (PSP). The activity was expressed in mouse unit (MU) being defined as the amount of TTX to kill a 20 g ddY male mice in 30 min after i.p. injection. Toxicity scores for viscera and appendages of specimens were 18.2 ± 16.0 (mean ± S.D.) and 4.4 ± 2.6 MU/g, respectively. The highest individual toxicity scores observed for viscera and appendages were 52.1 and 7.7 MU/g, respectively. The frequency of toxic samples was 100%. Toxin profiles as determined by high-performance liquid chromatography-fluorescent detection analysis (HPLC-FLD) revealed that TTX was the main toxic principle accounting for about 90% of the total toxicity along with 4-epi TTX and 4,9-anhydroTTX. Furthermore, gas chromatography-mass spectrometry (GC-MS) analysis revealed mass fragment ion peaks at m/z 376, 392 and 407, which were characteristic of the quinazoline skeleton (C9-base) specific to TTX. In addition, only a small amount of PSP containing gonyautoxins1–4 and hydroxysaxitoxin was detected. To our knowledge, this is the first report presenting evidence of occurrence of TTX and PSP in the xanthid crab D. cultripes inhabiting waters surrounding Cebu Island. From food hygienic point of view, people in coastal areas should be warned of the potential hazard of this crab in order to prevent its intentional or accidental consumption. PMID:21209702

Biomarker discovery in biological specimens (plasma, hair, liver and kidney) of diabetic mice based upon metabolite profiling using ultra-performance liquid chromatography with electrospray ionization time-of-flight mass spectrometry.

PubMed

Tsutsui, Haruhito; Maeda, Toshio; Min, Jun Zhe; Inagaki, Shinsuke; Higashi, Tatsuya; Kagawa, Yoshiyuki; Toyo'oka, Toshimasa

2011-05-12

The number of diabetic patients has recently been increasing worldwide. Diabetes is a multifactorial disorder based on environmental factors and genetic background. In many cases, diabetes is asymptomatic for a long period and the patient is not aware of the disease. Therefore, the potential biomarker(s), leading to the early detection and/or prevention of diabetes mellitus, are strongly required. However, the diagnosis of the prediabetic state in humans is a very difficult issue, because the lifestyle is variable in each person. Although the development of a diagnosis method in humans is the goal of our research, the extraction and structural identification of biomarker candidates in several biological specimens (i.e., plasma, hair, liver and kidney) of ddY strain mice, which undergo naturally occurring diabetes along with aging, were carried out based upon a metabolite profiling study. The low-molecular-mass compounds including metabolites in the biological specimens of diabetic mice (ddY-H) and normal mice (ddY-L) were globally separated by ultra-performance liquid chromatography (UPLC) using different reversed-phase columns (i.e., T3-C18 and HS-F5) and detected by electrospray ionization time-of-flight mass spectrometry (ESI-TOF-MS). The biomarker candidates related to diabetes mellitus were extracted from a multivariate statistical analysis, such as an orthogonal partial least-squares-discriminant analysis (OPLS-DA), followed by a database search, such as ChemSpider, KEGG and HMDB. Many metabolites and unknown compounds in each biological specimen were detected as the biomarker candidates related to diabetic mellitus. Among them, the elucidation of the chemical structures of several possible metabolites, including more than two biological specimens, was carried out along with the comparison of the tandem MS/MS analyses using authentic compounds. One metabolite was clearly identified as N-acetyl-L-leucine based upon the MS/MS spectra and the retention time on the chromatograms. N-acetyl-L-leucine is an endogenous compound included in all biological specimens (plasma, hair, liver and kidney). Therefore, this metabolite appears to be a potential biomarker candidate related to diabetes. Although the structures of other biomarker candidates have still not yet determined, the present approach based upon a metabolite profiling study using UPLC-ESI-TOF-MS could be helpful for understanding the abnormal state of various diseases. Copyright © 2010 Elsevier B.V. All rights reserved.

Permeabilities of rebamipide via rat intestinal membranes and its colon specific delivery using chitosan capsule as a carrier

PubMed Central

Huang, Bei-Bei; Li, Guo-Feng; Luo, Jing-Hui; Duan, Lian; Nobuaki, Kishimoto; Akira, Yamamoto

2008-01-01

AIM: To investigate the permeability characteristics of rebamipide across intestinal mucosa, and examine the effects of some absorption enhancers on the permeability across the colonic tissue. Another purpose is to demonstrate the colon-specific delivery of rebamipide with or without absorption enhancers using chitosan capsule as a carrier. METHODS: The permeability of rebamipide was evaluated using an in vitro diffusion chamber system, and the effects of some absorption enhancers on the permeability via colon were further investigated. The release of rebamipide from chitosan or gelatin capsule was studied by Japan Pharmacopoeia rotating basket method. The colonic and plasma concentrations were analyzed by high performance liquid chromatography (HPLC) to evaluate colon-targeting action after oral administration of various dosage forms, and rebamipide with absorption enhancers in chitosan dosage forms. RESULTS: The permeability of rebamipide across the jejunal or ileal membranes was higher than the colonic membranes. Both sodium laurate (C12) and labrasol significantly increased permeability across the colon membranes. On the other hand, the release of rebamipide from chitosan capsule was less than 10% totally within 6 h. The area under concentration-time profile of drug in the colon mucosa using chitosan capsules (AUCLI, 1 6011.2 ng·h/g) was 2.5 times and 4.4 times greater than using gelatin capsules and CMC suspension, respectively. Meanwhile, the area under concentration-time profile of drug in the plasma (AUCPL) was 1016.0 ng·h/mL for chitosan capsule, 1887.9 ng·h/mL for CMC suspension p and 2163.5 ng·h/mL for gelatin capsule. Overall, both AUCLI and AUCPL were increased when C12 was co-administrated, but the increase of AUCLI was much greater; the drug delivery index (DDI) was more than 1 compared with simple chitosan capsule group. CONCLUSION: There was a regional difference in the permeability of Rebamipide across the jejunum, ileum and the colon, and passive diffusion seems to be one of the major transport mechanisms of rebamipide. Absorption enhancers can increase the permeability of rebamipide across the colon tissue significantly. In addition, chitosan capsule may be a useful carrier to deliver rebamipide to the colon specifically and the co-administration of C12 with rebamipide may also be very useful in local treatment. PMID:18756602

Pharmacokinetic drug interactions with clopidogrel: updated review and risk management in combination therapy

PubMed Central

Wang, Zhi-Yu; Chen, Meng; Zhu, Ling-Ling; Yu, Lu-Shan; Zeng, Su; Xiang, Mei-Xiang; Zhou, Quan

2015-01-01

Background Coprescribing of clopidogrel and other drugs is common. Available reviews have addressed the drug–drug interactions (DDIs) when clopidogrel is as an object drug, or focused on combination use of clopidogrel and a special class of drugs. Clinicians may still be ignorant of those DDIs when clopidogrel is a precipitant drug, the factors determining the degree of DDIs, and corresponding risk management. Methods A literature search was performed using PubMed, MEDLINE, Web of Science, and the Cochrane Library to analyze the pharmacokinetic DDIs of clopidogrel and new P2Y12 receptor inhibitors. Results Clopidogrel affects the pharmacokinetics of cerivastatin, repaglinide, ferulic acid, sibutramine, efavirenz, and omeprazole. Low efficacy of clopidogrel is anticipated in the presence of omeprazole, esomeprazole, morphine, grapefruit juice, scutellarin, fluoxetine, azole antifungals, calcium channel blockers, sulfonylureas, and ritonavir. Augmented antiplatelet effects are anticipated when clopidogrel is coprescribed with aspirin, curcumin, cyclosporin, St John’s wort, rifampicin, and angiotensin-converting enzyme inhibitors. The factors determining the degree of DDIs with clopidogrel include genetic status (eg, cytochrome P540 [CYP]2B6*6, CYP2C19 polymorphism, CYP3A5*3, CYP3A4*1G, and CYP1A2-163C.A), species differences, and dose strength. The DDI risk does not exhibit a class effect, eg, the effects of clopidogrel on cerivastatin versus other statins, the effects of proton pump inhibitors on clopidogrel (omeprazole, esomeprazole versus pantoprazole, rabeprazole), the effects of rifampicin on clopidogrel versus ticagrelor and prasugrel, and the effects of calcium channel blockers on clopidogrel (amlodipine versus P-glycoprotein-inhibiting calcium channel blockers). The mechanism of the DDIs with clopidogrel involves modulating CYP enzymes (eg, CYP2B6, CYP2C8, CYP2C19, and CYP3A4), paraoxonase-1, hepatic carboxylesterase 1, P-glycoprotein, and organic anion transporter family member 1B1. Conclusion Effective and safe clopidogrel combination therapy can be achieved by increasing the awareness of potential changes in efficacy and toxicity, rationally selecting alternatives, tailoring drug therapy based on genotype, checking the appropriateness of physician orders, and performing therapeutic monitoring. PMID:25848291

Les neuropathies liées au VIH/SIDA: une étude clinique chez les patients infectés par le VIH au Centre d'Excellence VIH/SIDA de l'Université de Lubumbashi

PubMed Central

Kabongo, Joe Katabwa; Kaputu-Kalala-Malu, Célestin; Luboya, Oscar; Mutombo, Valerien; Ntambwe, Abel; Mapatano, Mala Ali; Mukendi, Kavulu Mayamba

2015-01-01

Introduction En vue d'améliorer la prise en charge des patients souffrant de neuropathie (NP) associées à l'infection HIV, nous avons essayé de déterminer le profil clinique des personnes souffrant de NP au cours du suivi thérapeutique de leur infection HIV. Méthodes Il s'agit d'une étude transversale (n= 101) menée au centre d'excellence depuis 1 an. Notre analyse est essentiellement clinique. Par un examen clinique minutieux, nous avons recherché tous les symptômes et signes cliniques des NP. Subjectivement, les douleurs dominent le tableau. Pour affiner leur diagnostic, nous avons utilisé l’échelle DN4 (Diagnostic des douleurs neuropathiques) et l’échelle EVA (Evaluation de la gravité des douleurs). Nous avons ensuite analysé nos données en fonction de certains autres facteurs épidémiologiques tels que le taux des CD4, le traitement anti-HIV etc. Résultats Les 101 patients représentent 3,12% de la cohorte générale; 53,3% des patients présentent une abolition des réflexes ostéotendineux des membres inférieurs; 77,89% présentent une hypoesthésie thermo algique en chaussette et en gants; 25% ont présenté une amyotrophie des membres inférieurs; 76,5% ont été soumis à un traitement antirétroviral contenant la stavudine; 11,7% ont pris la didanosine (DDI) et Abacavir (ABC). 84% ont une moyenne de CD4 de 292 cel/mm3. Conclusion La NP altère la qualité de vie de nos patients et diminue l'adhérence au traitement antirétroviral. Plusieurs facteurs sont incriminés dans la survenue de la NP, l'effet direct des antirétroviraux, l'effet inflammatoire dysimmunitaire, l'effet infectieux lié aux infections opportunistes. D'autres facteurs seront recherchés et analysés ultérieurement. PMID:26185582

Tissue Engineering of the Urethra: A Systematic Review and Meta-analysis of Preclinical and Clinical Studies.

PubMed

Versteegden, Luuk R M; de Jonge, Paul K J D; IntHout, Joanna; van Kuppevelt, Toin H; Oosterwijk, Egbert; Feitz, Wout F J; de Vries, Rob B M; Daamen, Willeke F

2017-10-01

Urethra repair by tissue engineering has been extensively studied in laboratory animals and patients, but is not routinely used in clinical practice. To systematically investigate preclinical and clinical evidence of the efficacy of tissue engineering for urethra repair in order to stimulate translation of preclinical studies to the clinic. A systematic search strategy was applied in PubMed and EMBASE. Studies were independently screened for relevance by two reviewers, resulting in 80 preclinical and 23 clinical studies of which 63 and 13 were selected for meta-analysis to assess side effects, functionality, and study completion. Analyses for preclinical and clinical studies were performed separately. Full circumferential and inlay procedures were assessed independently. Evaluated parameters included seeding of cells and type of biomaterial. Meta-analysis revealed that cell seeding significantly reduced the probability of encountering side effects in preclinical studies. Remarkably though, cells were only sparsely used in the clinic (4/23 studies) and showed no significant reduction of side effects. ln 21 out of 23 clinical studies, decellularized templates were used, while in preclinical studies other biomaterials showed promising outcomes as well. No direct comparison to current clinical practice could be made due to the limited number of randomized controlled studies. Due to a lack of controlled (pre)clinical studies, the efficacy of tissue engineering for urethra repair could not be determined. Meta-analysis outcome measures were similar to current treatment options described in literature. Surprisingly, it appeared that favorable preclinical results, that is inclusion of cells, were not translated to the clinic. Improved (pre)clinical study designs may enhance clinical translation. We reviewed all available literature on urethral tissue engineering to assess the efficacy in preclinical and clinical studies. We show that improvements to (pre)clinical study design is required to improve clinical translation of tissue engineering technologies. Copyright © 2017 European Association of Urology. Published by Elsevier B.V. All rights reserved.

[A Critical Condition of Clinical Studies in Japan -- A Battle of Clinical Study Groups].

PubMed

Furukawa, Hiroshi

2016-04-01

The post-marketing clinical study groups have been losing their activity due to stop of financial support. As the result, clinical study groups cannot achieve any EBM for treatment guidelines. Financial supports should be restarted immediately not to extinguish the post-marketing clinical studies and study groups.

Poor relation between biomechanical and clinical studies for the proximal femoral locking compression plate

PubMed Central

Viberg, Bjarke; Rasmussen, Katrine M V; Overgaard, Søren; Rogmark, Cecilia

2017-01-01

Background and purpose The proximal femur locking compression plate (PF-LCP) is a new concept in the treatment of hip fractures. When releasing new implants onto the market, biomechanical studies are conducted to evaluate performance of the implant. We investigated the relation between biomechanical and clinical studies on PF-LCP. Methods A systematic literature search of relevant biomechanical and clinical studies was conducted in PubMed on December 1, 2015. 7 biomechanical studies and 15 clinical studies were included. Results Even though the biomechanical studies showed equivalent or higher failure loads for femoral neck fracture, the clinical results were far worse, with a 37% complication rate. There were no biomechanical studies on pertrochanteric fractures. Biomechanical studies on subtrochanteric fractures showed that PF-LCP had a lower failure load than with proximal femoral nail, but higher than with angled blade plate. 4 clinical studies had complication rates less than 8% and 9 studies had complication rates between 15% and 53%. Interpretation There was no clear relation between biomechanical and clinical studies. Biomechanical studies are generally inherently different from clinical studies, as they examine the best possible theoretical use of the implant without considering the long-term outcome in a clinical setting. Properly designed clinical studies are mandatory when introducing new implants, and they cannot be replaced by biomechanical studies. PMID:28287002

[Clinical research=design*measurements*statistical analyses].

PubMed

Furukawa, Toshiaki

2012-06-01

A clinical study must address true endpoints that matter for the patients and the doctors. A good clinical study starts with a good clinical question. Formulating a clinical question in the form of PECO can sharpen one's original question. In order to perform a good clinical study one must have a knowledge of study design, measurements and statistical analyses: The first is taught by epidemiology, the second by psychometrics and the third by biostatistics.

Muscarinic receptor subtypes involved in carbachol-induced contraction of mouse uterine smooth muscle.

PubMed

Kitazawa, Takio; Hirama, Ryuichi; Masunaga, Kozue; Nakamura, Tatsuro; Asakawa, Koichi; Cao, Jinshan; Teraoka, Hiroki; Unno, Toshihiro; Komori, Sei-ichi; Yamada, Masahisa; Wess, Jürgen; Taneike, Tetsuro

2008-06-01

Functional muscarinic acetylcholine receptors present in the mouse uterus were characterized by pharmacological and molecular biological studies using control (DDY and wild-type) mice, muscarinic M2 or M3 single receptor knockout (M2KO, M3KO), and M2 and M3 receptor double knockout mice (M2/M3KO). Carbachol (10 nM-100 microM) increased muscle tonus and phasic contractile activity of uterine strips of control mice in a concentration-dependent manner. The maximum carbachol-induced contractions (Emax) differed between cervical and ovarian regions of the uterus. The stage of the estrous cycle had no significant effect on carbachol concentration-response relationships. Tetrodotoxin did not decrease carbachol-induced contractions, but the muscarinic receptor antagonists (11-[[2-[(diethylaminomethyl)-1-piperidinyl]acetyl]-5,11-dihydro-6H-pyrido[2,3-b[2,3-b][1,4]benzodiazepin6-one (AF-DX116), N-[2-[2-[(dipropylamino)methyl]-1-piperidinyl]ethyl]-5,6-dihydro-6-oxo-11H-pyrido[2,3-b][1,4] benzodiazepine-11-carboxamide (AF-DX384), 4-diphenylacetoxy-N-methyl-piperidine(4-DAMP), para-fluoro-hexa hydro-sila-diphenidol (p-F-HHSiD), himbacine, methoctramine, pirenzepine, and tropicamide) inhibited carbachol-induced contractions in a competitive fashion. The pKb values for these muscarinic receptor antagonists correlated well with the known pKi values of these antagonists for the M3 muscarinic receptor. In uterine strips isolated from mice treated with pertussis toxin (100 microg/kg, i.p. for 96 h), Emax values for carbachol were significantly decreased, but effective concentration that caused 50% of Emax values (EC50) remained unchanged. In uterine strips treated with 4-DAMP mustard (30 nM) and AF-DX116 (1 microM), followed by subsequent washout of AF-DX116, neither carbachol nor N,N,N,-trimethyl-4-(2-oxo-1-pyrolidinyl)-2-butyn-1-ammonium iodide (oxotremorine-M) caused any contractile responses. Both M2 and M3 muscarinic receptor messenger RNAs were detected in the mouse uterus via reverse transcription polymerase chain reaction. Carbachol also caused contraction of uterine strips isolated from M2KO mice, but the concentration-response curve was shifted to the right and downward compared with that for the corresponding wild-type mice. On the other hand, uterine strips isolated from M3KO and M2/M3 double KO mice were virtually insensitive to carbachol. In conclusion, although both M2 and M3 muscarinic receptors were expressed in the mouse uterus, carbachol-induced contractile responses were predominantly mediated by the M3 receptor. Activation of M2 receptors alone did not cause uterine contractions; however, M2 receptor activation enhanced M3 receptor-mediated contractions in the mouse uterus.

[Teaching of clinical reasoning to medical students using prototypical clinical cases].

PubMed

Montaldo L, Gustavo; Herskovic L, Pedro

2013-07-01

Clinical reasoning is the most important competente in the training process of a physician. To develop a method for teaching clinical reasoning based on prototypes of clinical cases. The study was conducted on sixty-four third year medical students. The study and control groups attended lectures and tutorial sessions with patients. The study group attended additionally discussion seminars of prototypical clinical cases. A clinical reasoning test was applied at the start and end of the learning period to both groups. At the end of the study, the opinions of students of the study group were collected in a focus group. After the learning period, both groups significantly increased their clinical reasoning skills. However, the improvement in the study group was more than double than that of the control group. The absolute improvement in the study group was 30.9%. Students interviewed in the focus group were unanimous in expressing their satisfaction in each and every aspect discussed. The teaching of clinical reasoning to third year medical students by means of pattern recognition in seminars with clinical cases improved significantly their skills.

Driving clinical study efficiency by using a productivity breakdown model: comparative evaluation of a global clinical study and a similar Japanese study.

PubMed

Takahashi, K; Sengoku, S; Kimura, H

2011-02-01

A fundamental management imperative of pharmaceutical companies is to contain surging costs of developing and launching drugs globally. Clinical studies are a research and development (R&D) cost driver. The objective of this study was to develop a productivity breakdown model, or a key performance indicator (KPI) tree, for an entire clinical study and to use it to compare a global clinical study with a similar Japanese study. We, thereby, hope to identify means of improving study productivity. We developed the new clinical study productivity breakdown model, covering operational aspects and cost factors. Elements for improving clinical study productivity were assessed from a management viewpoint by comparing empirical tracking data from a global clinical study with a Japanese study with similar protocols. The following unique and material differences, beyond simple international difference in cost of living, that could affect the efficiency of future clinical trials were identified: (i) more frequent site visits in the Japanese study, (ii) head counts at the Japanese study sites more than double those of the global study and (iii) a shorter enrollment time window of about a third that of the global study at the Japanese study sites. We identified major differences in the performance of the two studies. These findings demonstrate the potential of the KPI tree for improving clinical study productivity. Trade-offs, such as those between reduction in head count at study sites and expansion of the enrollment time window, must be considered carefully. © 2010 Blackwell Publishing Ltd.

[Features of Clinical Register of Chinese Medicine and Pharmacy Based on ClinicalTrials.gov. (USA)].

PubMed

Lu, Peng-fei; Liao, Xing; Xie, Yan-ming; Wang, Zhi-guo

2015-11-01

In recent 10 years, clinical trials of Chinese medicine and pharmacy (cMP) at clinicalTrials.gov.(USA) are gradually increasing. In order to analyze features of CMP clinical register, ClinicalTrials.gov register database were comprehensively retrieved in this study. Included clinical trials were input one item after another using EXCEL. A final of 348 CMP clinical trials were included. Results showed that China occupied the first place in CMP clinical register, followed by USA. CMP clinical trials, sponsored mainly by colleges/universities and hospitals, mostly covered interventional studies on evaluating safety/effectiveness of CMP. The proportions of studies, sponsored by mainland China and companies, recruitment trials and multi-center clinical trials in interventional trials were increasing. The proportions of studies sponsored by Hong Kong and Taiwan, research completed trials, unclear research status, phase III clinical trials, and published research trials in interventional trials were decreasing. Published ratios of CMP clinical trials were quite low. There were more missing types and higher proportions in trial register information.

78 FR 12664 - Human Subject Protection; Acceptance of Data From Clinical Studies for Medical Devices

Federal Register 2010, 2011, 2012, 2013, 2014

2013-02-25

... Clinical Studies for Medical Devices AGENCY: Food and Drug Administration, HHS. ACTION: Proposed rule... data from clinical studies for medical devices. We are proposing to require that clinical studies... the study by an independent ethics committee (IEC) and obtaining and documenting freely given informed...

Multiphase complete exchange on a circuit switched hypercube

NASA Technical Reports Server (NTRS)

Bokhari, Shahid H.

1991-01-01

On a distributed memory parallel computer, the complete exchange (all-to-all personalized) communication pattern requires each of n processors to send a different block of data to each of the remaining n - 1 processors. This pattern is at the heart of many important algorithms, most notably the matrix transpose. For a circuit switched hypercube of dimension d(n = 2(sup d)), two algorithms for achieving complete exchange are known. These are (1) the Standard Exchange approach that employs d transmissions of size 2(sup d-1) blocks each and is useful for small block sizes, and (2) the Optimal Circuit Switched algorithm that employs 2(sup d) - 1 transmissions of 1 block each and is best for large block sizes. A unified multiphase algorithm is described that includes these two algorithms as special cases. The complete exchange on a hypercube of dimension d and block size m is achieved by carrying out k partial exchange on subcubes of dimension d(sub i) Sigma(sup k)(sub i=1) d(sub i) = d and effective block size m(sub i) = m2(sup d-di). When k = d and all d(sub i) = 1, this corresponds to algorithm (1) above. For the case of k = 1 and d(sub i) = d, this becomes the circuit switched algorithm (2). Changing the subcube dimensions d, varies the effective block size and permits a compromise between the data permutation and block transmission overhead of (1) and the startup overhead of (2). For a hypercube of dimension d, the number of possible combinations of subcubes is p(d), the number of partitions of the integer d. This is an exponential but very slowly growing function and it is feasible over these partitions to discover the best combination for a given message size. The approach was analyzed for, and implemented on, the Intel iPSC-860 circuit switched hypercube. Measurements show good agreement with predictions and demonstrate that the multiphase approach can substantially improve performance for block sizes in the 0 to 160 byte range. This range, which corresponds to 0 to 40 floating point numbers per processor, is commonly encountered in practical numeric applications. The multiphase technique is applicable to all circuit-switched hypercubes that use the common e-cube routing strategy.

The effects on weight loss and gene expression in adipose and hepatic tissues of very-low carbohydrate and low-fat isoenergetic diets in diet-induced obese mice.

PubMed

Yamazaki, Tomomi; Okawa, Sumire; Takahashi, Mayumi

2016-01-01

Obesity is caused by excessive fat or carbohydrate intake. The improvement of obesity is an important issue, especially in Western societies. Both low-carbohydrate diet (LCD) and low-fat diet (LFD) are used to achieve weight loss in humans. To clarify the mechanisms underlying LCD-induced weight loss, especially in early stage, we compared the gene expression in liver, white adipose tissue (WAT) and brown adipose tissue (BAT) of a very-low carbohydrate diet (VLCD)- and LFD-fed diet-induced obese (DIO) mice. DIO male ddY mice were divided into high-fat diet (HFD), and isoenergetic VLCD and LFD groups. Pair-feeding was performed in the VLCD and LFD groups. Three weeks later, the body, liver, WAT and BAT were weighed and the serum and hepatic lipids, the mRNA expression levels in each tissue, and energy metabolism were analyzed. The caloric intake of the VLCD-fed mice was initially reduced but was subsequently restored. The total energy intake was similar in the VLCD- and LFD-fed mice. There was a similar decrease in the BW of the VLCD- and LFD-fed mice. The VLCD-fed mice had elevated levels of serum fibroblast growth factor 21 (FGF21) and ketone bodies, which are known to increase energy expenditure. The browning of WAT was observed to a greater extent in the VLCD-fed mice. Moreover, in the VLCD-fed mice, BAT activation was observed, the weight of the BAT was decreased, and the expression of G-protein-coupled receptor 120, type 2 iodothyronine deiodinase, and FGF21 in BAT was extremely increased. Although the energy expenditure of the VLCD- and LFD-fed mice did not differ, that of the VLCD-fed mice was sometimes higher during the dark cycle. Hepatic TG accumulation was reduced in LFD-fed mice due to their decreased fatty acid uptake but not in the VLCD-fed mice. The pro-inflammatory macrophage ratio was increased in the WAT of VLCD-fed mice. After 3 weeks, the isoenergetic VLCD- and LFD-fed DIO mice showed similar weight loss. The VLCD-fed mice increased serum concentration of FGF21 and ketone bodies, and marker mRNA levels of browning in WAT, activation in BAT and hepatic lipogenesis.

Sigma1 receptor antagonists determine the behavioral pattern of the methamphetamine-induced stereotypy in mice

PubMed Central

Kitanaka, J.; Kitanaka, N.; Tatsuta, T.; Hall, F.S.; Uhl, G.R.; Tanaka, K.; Nishiyama, N.; Morita, Y.; Takemura, M.

2011-01-01

Objective The effects of sigma receptor antagonists on methamphetamine (METH)-induced stereotypy have not been examined. We examined the effects of sigma antagonists on METH-induced stereotypy in mice. Results The administration of METH (10 mg/kg) to male ddY mice induced stereotyped behavior consisting of biting (90.1%), sniffing (4.2%), head bobbing (4.1%), and circling (1.7%) during an observation period of 1 h. Pretreatment of the mice with BMY 14802 (α-(4-fluorophenyl)-4-(5-fluoro-2-pyrimidinyl)-1-piperazinebutanol; 1, 5, and 10 mg/kg), a non-specific sigma receptor antagonist, significantly increased METH-induced sniffing (19.2, 30.5, and 43.8% of total stereotypical behavior) but decreased biting (76.6, 66.9, and 49.3% of total stereotypical behavior) in a dose-dependent manner. This response was completely abolished by (+)-SKF 10,047 ([2S-(2α,6α,11R)]-1,2,3,4,5,6-hexahydro-6,11-dimethyl-3-(2-propenyl)-2,6-methano-3-benzazocin-8-ol; 4 and 10 mg/kg), a putative sigma1 receptor agonist, and partially by PB 28 (1-cyclohexyl-4-[3-(1,2,3,4-tetrahydro-5-methoxy-1-naphthalen-1-yl)-n-propyl]piperazine; 1 and 10 mg/kg), a putative sigma2 receptor agonist. The BMY 14802 action on METH-induced stereotypy was mimicked by BD 1047 (N-[2-(3,4-dichlorophenyl)ethyl]-N-methyl-2-(dimethylamino)ethylamine; 10 mg/kg), a putative sigma1 receptor antagonist, but not by SM-21 ((±)-tropanyl 2-(4-chlorophenoxy)butanoate; 1 mg/kg), a putative sigma2 receptor antagonist. The BD 1047 effect on METH-induced stereotypy was also abolished completely by (+)-SKF 10,047 and partially by PB 28. The overall frequency of METH-induced stereotypical behavior was unchanged with these sigma receptor ligands, despite the alteration in particular behavioral patterns. The BMY 14802 action on METH-induced stereotypy was unaffected by pretreatment with centrally acting histamine H1 receptor antagonists (pyrilamine or ketotifen, 10 mg/kg), suggesting that these effects are independent of histamine H1 receptor signaling systems. Conclusion In summary, modulation of central sigma1 receptors alters the pattern of METH-induced stereotypy, producing a shift from stereotypical biting to stereotypical sniffing, without affecting the overall frequency of stereotypical behavior. PMID:19052726

Évolution des conditions d’initiation du traitement antirétroviral des patients infectés par le VIH en Afrique de l’Ouest

PubMed Central

Bashi, J.; Balestre, E.; Messou, E.; Maiga, M.; Coffie, P.A.; Zannou, D.M.; Ba-Gomis, O.; Traore, H.A.; Eholie, S.; Minga, A.; Sow, P.S.; Bissagnene, E.; Dabis, F.; Ekouevi, D.K.

2013-01-01

Résumé Objectif Étudier entre 1996 et 2006, l’évolution des schémas thérapeutiques et du profil clinique et immunologique des patients infectés par le VIH au début du traitement antirétroviral (TARV) en Afrique de l’Ouest. Cadre et méthode Les données issues de 12 centres cliniques adultes (IeDEA West Africa réseau collaboratif de prise en charge de l’infection à VIH) de cinq pays (Bénin, Cote d’Ivoire, Sénégal, Gambie, Mali) ont été mises en commun et analysées. Les patients âgés de 16 ans et plus dont le sexe, la date de naissance et la date d’initiation du TARV étaient connus ont été inclus dans cette étude. Résultats Quatorze mille quatre-cent-quatre-vingt-seize patients avaient débuté un TARV entre 1996–2006 avec 55 % des patients l’ayant débuté entre 2005–2006. La proportion de femmes était de 46 % en 1996–2000 et de 63 % en 2005–2006. L’âge médian à la mise sous traitement était constant: 35 ans chez les femmes et 40 ans chez les hommes. La proportion de patients qui ont débuté le TARV avec un taux de CD4 inférieur à 200 cellules/µl était de 54 % en 1996–2000 et de 64 % en 2005–2006. Les combinaisons thérapeutiques les plus prescrites étaient: AZT/3TC (ou d4T/DDI)/IDV (27 %) en 1996–2000; d4T (ou AZT)/3TC/EFV (59 %) en 2003–2004; et d4T/3TC/NVP (49 %) en 2005–2006. Les traitements de première ligne recommandés par l’OMS étaient débutés dans 83 % de cas en 2005–2006. Conclusion De nouvelles approches pour débuter un TARV plus précocement doivent être développées pour améliorer la survie des patients sous TARV. PMID:20045273

ClinicalTrials.gov

MedlinePlus

... Terms and Conditions Disclaimer ClinicalTrials.gov is a database of privately and publicly funded clinical studies conducted ... world. ClinicalTrials.gov is a registry and results database of publicly and privately supported clinical studies of ...

Reporting of harms outcomes: a comparison of journal publications with unpublished clinical study reports of orlistat trials.

PubMed

Hodkinson, Alex; Gamble, Carrol; Smith, Catrin Tudur

2016-04-22

The quality of harms reporting in journal publications is often poor, which can impede the risk-benefit interpretation of a clinical trial. Clinical study reports can provide more reliable, complete, and informative data on harms compared to the corresponding journal publication. This case study compares the quality and quantity of harms data reported in journal publications and clinical study reports of orlistat trials. Publications related to clinical trials of orlistat were identified through comprehensive literature searches. A request was made to Roche (Genentech; South San Francisco, CA, USA) for clinical study reports related to the orlistat trials identified in our search. We compared adverse events, serious adverse events, and the reporting of 15 harms criteria in both document types and compared meta-analytic results using data from the clinical study reports against the journal publications. Five journal publications with matching clinical study reports were available for five independent clinical trials. Journal publications did not always report the complete list of identified adverse events and serious adverse events. We found some differences in the magnitude of the pooled risk difference between both document types with a statistically significant risk difference for three adverse events and two serious adverse events using data reported in the clinical study reports; these events were of mild intensity and unrelated to the orlistat. The CONSORT harms reporting criteria were often satisfied in the methods section of the clinical study reports (70-90 % of the methods section criteria satisfied in the clinical study reports compared to 10-50 % in the journal publications), but both document types satisfied 80-100 % of the results section criteria, albeit with greater detail being provided in the clinical study reports. In this case study, journal publications provided insufficient information on harms outcomes of clinical trials and did not specify that a subset of harms data were being presented. Clinical study reports often present data on harms, including serious adverse events, which are not reported or mentioned in the journal publications. Therefore, clinical study reports could support a more complete, accurate, and reliable investigation, and researchers undertaking evidence synthesis of harm outcomes should not rely only on incomplete published data that are presented in the journal publications.

Pre-admission criteria and pre-clinical achievement: Can they predict medical students performance in the clinical phase?

PubMed

Salem, Raneem O; Al-Mously, Najwa; AlFadil, Sara; Baalash, Amal

2016-01-01

Various factors affect medical students' performance during clinical phase. Identifying these factors would help in mentoring weak students and help in selection process for residency programmes. Our study objective is to evaluate the impact of pre-admission criteria, and pre-clinical grade point average (GPA) on undergraduate medical students' performance during clinical phase. This study has a cross-sectional design that includes fifth- and sixth-year female medical students (71). Data of clinical and pre-clinical GPA in medical school and pre-admission to medical school tests scores were collected. A significant correlation between clinical GPA with the pre-clinical GPA was observed (p < 0.05). Such significant correlation was not seen with other variables under study. A regression analysis was performed, and the only significant predictor of students clinical performance was the pre-clinical GPA (p < 0.001). However, no significant difference between students' clinical and pre-clinical GPA for both cohorts was observed (p > 0.05). Pre-clinical GPA is strongly correlated with and can predict medical students' performance during clinical years. Our study highlighted the importance of evaluating the academic performances of students in pre-clinical years before they move into clinical years in order to identify weak students to mentor them and monitor their progress.

Opioid-Sparing Effect of Cannabinoids: A Systematic Review and Meta-Analysis.

PubMed

Nielsen, Suzanne; Sabioni, Pamela; Trigo, Jose M; Ware, Mark A; Betz-Stablein, Brigid D; Murnion, Bridin; Lintzeris, Nicholas; Khor, Kok Eng; Farrell, Michael; Smith, Andrew; Le Foll, Bernard

2017-08-01

Cannabinoids, when co-administered with opioids, may enable reduced opioid doses without loss of analgesic efficacy (ie, an opioid-sparing effect). The aim of this study was to conduct a systematic review to determine the opioid-sparing potential of cannabinoids. Eligible studies included pre-clinical and clinical studies for which the outcome was either analgesia or opioid dose requirements. Clinical studies included controlled studies and case series. We searched Scopus, Cochrane Database of Systematic Reviews, Medline, and Embase. Nineteen pre-clinical and nine clinical studies met the search criteria. Seventeen of the 19 pre-clinical studies provided evidence of synergistic effects from opioid and cannabinoid co-administration. Our meta-analysis of pre-clinical studies indicated that the median effective dose (ED 50 ) of morphine administered in combination with delta-9-tetrahydrocannabinol (delta-9-THC) is 3.6 times lower (95% confidence interval (CI) 1.95, 6.76; n=6) than the ED 50 of morphine alone. In addition, the ED 50 for codeine administered in combination with delta-9-THC was 9.5 times lower (95% CI 1.6, 57.5, n=2) than the ED 50 of codeine alone. One case series (n=3) provided very-low-quality evidence of a reduction in opioid requirements with cannabinoid co-administration. Larger controlled clinical studies showed some clinical benefits of cannabinoids; however, opioid dose changes were rarely reported and mixed findings were observed for analgesia. In summary, pre-clinical studies provide robust evidence of the opioid-sparing effect of cannabinoids, whereas one of the nine clinical studies identified provided very-low-quality evidence of such an effect. Prospective high-quality-controlled clinical trials are required to determine the opioid-sparing effect of cannabinoids.

The case for introducing pre-registered confirmatory pharmacological pre-clinical studies.

PubMed

Kiwanuka, Olivia; Bellander, Bo-Michael; Hånell, Anders

2018-05-01

When evaluating the design of pre-clinical studies in the field of traumatic brain injury, we found substantial differences compared to phase III clinical trials, which in part may explain the difficulties in translating promising experimental drugs into approved treatments. By using network analysis, we also found cases where a large proportion of the studies evaluating a pre-clinical treatment was performed by inter-related researchers, which is potentially problematic. Subjecting all pre-clinical trials to the rigor of a phase III clinical trial is, however, likely not practically achievable. Instead, we repeat the call for a distinction to be made between exploratory and confirmatory pre-clinical studies.

Nurses’ Clinical Judgment Development: A Qualitative Research in Iran

PubMed Central

Seidi, Jamal; Alhani, Fatemeh; Salsali, Mahvash

2015-01-01

Background: Clinical judgment development is necessary because it leads to appropriate nursing diagnoses, clinical decision-making and health promotion. Objectives: In this study we explored the process of Iranian nurses’ development in clinical judgment. Patients and Methods: This qualitative study was conducted in 2013 at hospitals of Kurdistan University of Medical Sciences, located in the Sanandaj city of Iran. The data were collected based on semi-structured interviews and the study included 24 participants. Data analysis was carried out concurrently with data collection using the grounded theory method. Results: The study participants’ main concern was ‘being non-professional in clinical judgment’. In response to this concern, they were struggling for gaining professional autonomy, striving for integrating clinical judgment skills, scrambling to make effective educational interventions and striving for professional and inter professional collaboration in clinical judgment. The core category was ‘struggling for becoming professional in clinical judgment development’. When nurses were supported professionally, they were able to develop their professional clinical judgment. Conclusions: The findings of this study provided critical information about nurses’ professionalization in clinical judgment. Accordingly, the participants adopted different strategies to develop their clinical judgment ability. Integrating these strategies into nursing theory and clinical education can improve nurses’ clinical judgment ability. PMID:26473075

How good is "evidence" from clinical studies of drug effects and why might such evidence fail in the prediction of the clinical utility of drugs?

PubMed

Naci, Huseyin; Ioannidis, John P A

2015-01-01

Promising evidence from clinical studies of drug effects does not always translate to improvements in patient outcomes. In this review, we discuss why early evidence is often ill suited to the task of predicting the clinical utility of drugs. The current gap between initially described drug effects and their subsequent clinical utility results from deficits in the design, conduct, analysis, reporting, and synthesis of clinical studies-often creating conditions that generate favorable, but ultimately incorrect, conclusions regarding drug effects. There are potential solutions that could improve the relevance of clinical evidence in predicting the real-world effectiveness of drugs. What is needed is a new emphasis on clinical utility, with nonconflicted entities playing a greater role in the generation, synthesis, and interpretation of clinical evidence. Clinical studies should adopt strong design features, reflect clinical practice, and evaluate outcomes and comparisons that are meaningful to patients. Transformative changes to the research agenda may generate more meaningful and accurate evidence on drug effects to guide clinical decision making.

An analysis of registered clinical trials in otolaryngology from 2007 to 2010: ClinicalTrials.gov.

PubMed

Witsell, David L; Schulz, Kristine A; Lee, Walter T; Chiswell, Karen

2013-11-01

To describe the conditions studied, interventions used, study characteristics, and funding sources of otolaryngology clinical trials from the ClinicalTrials.gov database; compare this otolaryngology cohort of interventional studies to clinical visits in a health care system; and assess agreement between clinical trials and clinical activity. Database analysis. Trial registration data downloaded from ClinicalTrials.gov and administrative data from the Duke University Medical Center from October 1, 2007 to September 27, 2010. Data extraction from ClinicalTrials.gov was done using MeSH and non-MeSH disease condition terms. Studies were subcategorized to create the following groupings for descriptive analysis: ear, nose, allergy, voice, sleep, head and neck cancer, thyroid, and throat. Duke Health System visits were queried by using selected ICD-9 codes for otolaryngology and non-otolaryngology providers. Visits were grouped similarly to ClinicalTrials.gov for further analysis. Chi-square tests were used to explore differences between groups. A total of 1115 of 40,970 registered interventional trials were assigned to otolaryngology. Head and neck cancer trials predominated. Study models most frequently incorporated parallel design (54.6%), 2 study groups (46.6%), and randomization (69.1%). Phase 2 or 3 studies constituted 46.4% of the cohort. Comparison of the ClinicalTrials.gov database with administrative health system visit data by disease condition showed discordance between national research activity and clinical visit volume for patients with otolaryngology complaints. Analysis of otolaryngology-related clinical research as listed in ClinicalTrials.gov can inform patients, physicians, and policy makers about research focus areas. The relative burden of otolaryngology-associated conditions in our tertiary health system exceeds research activity within the field.

Best practices for clinical pathology testing in carcinogenicity studies.

PubMed

Young, Jamie K; Hall, Robert L; O'Brien, Peter; Strauss, Volker; Vahle, John L

2011-02-01

The Society of Toxicologic Pathology (STP) and American Society for Veterinary Clinical Pathology (ASCVP) convened a Clinical Pathology in Carcinogenicity Studies Working Group to recommend best practices for inclusion of clinical pathology testing in carcinogenicity studies. Regulatory guidance documents and literature were reviewed, and veterinary pathologists from North America, Japan, and Europe were surveyed regarding current practices, perceived value, and recommendations for clinical pathology testing in carcinogenicity studies. For two-year rodent carcinogenicity studies, the Working Group recommends that clinical pathology testing be limited to collection of blood smears at scheduled and unscheduled sacrifices to be examined only if indicated to aid in the diagnosis of possible hematopoietic neoplasia following histopathologic evaluation. Additional clinical pathology testing is most appropriately used to address specific issues from prior toxicity studies or known test article-related class effects. Inadequate data were available to make a recommendation concerning clinical pathology testing for alternative six-month carcinogenicity assays using genetically modified mice, although the Working Group suggests that it may be appropriate to use the same approach as for two-year carcinogenicity studies since the study goal is the same.

Undergraduate nursing students' experience related to their clinical learning environment and factors affecting to their clinical learning process.

PubMed

Arkan, Burcu; Ordin, Yaprak; Yılmaz, Dilek

2018-03-01

Clinical education is an essential part of nursing education. The purpose of this study was to explore nurse students' experiences related to cinical learning environments, factors effecting to clinical learning process. Descriptive qualitative design was used in this study, and data were collected from 2nd class nursing student (n = 14). The study took the form of in-depth interviews between August-October 2015. The qualitative interviews were analyzed by using simple content analysis. Data were analyzed manually. Experiences nurse students are described five themes. The themes of the study are (1) effecting persons to clinical learning, (2) educational atmosphere, (3) students' personal charactering, (4) the impact of education in school, and (5) students' perceptions related to clinical learning. Participants stated that they experienced many difficulties during clinical learning process. All students importantly stated that nurse teacher is very effecting to clinical learning. This study contributes to the literature by providing data on beginner nursing student' experiences about clinical learning process. The data of this present study show to Turkish nursing student is affecting mostly from persons in clinical learning. The data of this present study will guide nurse teacher when they plan to interventions to be performed to support student during clinical learning process. Copyright © 2017 Elsevier Ltd. All rights reserved.

Analyzing global trends of biomarker use in drug interventional clinical studies.

PubMed

Hayashi, K; Masuda, S; Kimura, H

2012-04-01

The trend of biomarker use in drug interventional clinical studies was analyzed using ClinicalTrials.gov to provide an overview of how biomarkers are used to streamline clinical studies and to examine regional differences. A total of 3,383 clinical study data was analyzed according to phase, region, sponsor, and therapeutic class. The number of clinical studies using biomarkers has been increasing constantly and is dependent on the number of Phase I and II studies. The majority of studies (58.5%) were sponsored by the United States, with the studies being conducted mainly in the sponsor's home region (80.3%). The use of biomarkers was prominent in the oncology area (37.1%). Although current data indicates some bias in the clinical use of biomarkers, it is expected that their use will increase in later phase studies or other therapeutic areas as biomarker development proceeds. In addition, limited regional use of biomarkers may lead to differences in biomarker use in drug development and in combination with political support may result in differences in competitiveness of drug development. Biomarkers would be a powerful tool against deteriorating research and development productivity when used more in appropriate clinical study conditions.

Evaluation systems for clinical governance development: a comparative study.

PubMed

Hooshmand, Elaheh; Tourani, Sogand; Ravaghi, Hamid; Ebrahimipour, Hossein

2014-01-01

Lack of scientific and confirmed researches and expert knowledge about evaluation systems for clinical governance development in Iran have made studies on different evaluation systems for clinical governance development a necessity. These studies must provide applied strategies to design criteria of implementing clinical governance for hospital's accreditation. This is a descriptive and comparative study on development of clinical governance models all over the world. Data have been gathered by reviewing related articles. Models have been studied in comprehensive review method. The evaluated models of clinical governance development were Australian, NHS, SPOCK and OPTIGOV. The final aspects extracted from these models were Responsiveness, Policies and Strategies, Organizational Structure, Allocating Resources, Education and Occupational Development, Performance Evaluation, External Evaluation, Patient Oriented Approach, Risk Management, Personnel's Participation, Information Technology, Human Resources, Research and Development, Evidence Based Medicine, Clinical Audit, Health Technology Assessment and Quality. These results are applicable for completing the present criteria which evaluating clinical governance application and provide practical framework to evaluate country's hospital on the basis of clinical governance elements.

Recommendations for Clinical Pathology Data Generation, Interpretation, and Reporting in Target Animal Safety Studies for Veterinary Drug Development.

PubMed

Siska, William; Gupta, Aradhana; Tomlinson, Lindsay; Tripathi, Niraj; von Beust, Barbara

Clinical pathology testing is routinely performed in target animal safety studies in order to identify potential toxicity associated with administration of an investigational veterinary pharmaceutical product. Regulatory and other testing guidelines that address such studies provide recommendations for clinical pathology testing but occasionally contain outdated analytes and do not take into account interspecies physiologic differences that affect the practical selection of appropriate clinical pathology tests. Additionally, strong emphasis is often placed on statistical analysis and use of reference intervals for interpretation of test article-related clinical pathology changes, with limited attention given to the critical scientific review of clinically, toxicologically, or biologically relevant changes. The purpose of this communication from the Regulatory Affairs Committee of the American Society for Veterinary Clinical Pathology is to provide current recommendations for clinical pathology testing and data interpretation in target animal safety studies and thereby enhance the value of clinical pathology testing in these studies.

Improving Translation from Preclinical Studies to Clinical Trials in Acute Kidney Injury.

PubMed

Fiorentino, Marco; Kellum, John A

2018-05-23

Several cellular and molecular targets and mechanisms have been investigated in preclinical studies of acute kidney injury (AKI), but translation in successful clinical studies has failed to date. This article reviews many issues that have limited this and the potential future perspectives in AKI prevention and treatment. Preclinical models of AKI should closely mimic the complexity of human AKI, considering the importance of several comorbidities in determining the clinical course and outcomes in the human disease. Moreover, studies should test novel interventions in models where AKI is already established, instead of focusing only at primary prevention. AKI definitions and endpoints in animal studies should be similar to those applied in clinical studies; in particular, AKI biomarkers should be implemented to guide patient selection for clinical trials and monitor intervention efficacy. In this scenario, cell-cycle arrest biomarkers have been widely investigated as AKI predictors in both preclinical and clinical studies and they serve as useful tools for future interventional studies. A better understanding of human AKI through a large collection of biological samples and kidney biopsies and omics applications, and an iterative relationship between preclinical and clinical studies are critical steps to improve future preclinical models and clinical trials. Finally, given the great variability in clinical manifestation of AKI, a strong collaboration between research centers and industry is recommended. Key messages: Several methodological issues have hampered the translation of basic research findings in clinical studies, and overcoming these obstacles is necessary to achieve success. © 2018 S. Karger AG, Basel.

The Ontology of Clinical Research (OCRe): An Informatics Foundation for the Science of Clinical Research

PubMed Central

Sim, Ida; Tu, Samson W.; Carini, Simona; Lehmann, Harold P.; Pollock, Brad H.; Peleg, Mor; Wittkowski, Knut M.

2013-01-01

To date, the scientific process for generating, interpreting, and applying knowledge has received less informatics attention than operational processes for conducting clinical studies. The activities of these scientific processes — the science of clinical research — are centered on the study protocol, which is the abstract representation of the scientific design of a clinical study. The Ontology of Clinical Research (OCRe) is an OWL 2 model of the entities and relationships of study design protocols for the purpose of computationally supporting the design and analysis of human studies. OCRe’s modeling is independent of any specific study design or clinical domain. It includes a study design typology and a specialized module called ERGO Annotation for capturing the meaning of eligibility criteria. In this paper, we describe the key informatics use cases of each phase of a study’s scientific lifecycle, present OCRe and the principles behind its modeling, and describe applications of OCRe and associated technologies to a range of clinical research use cases. OCRe captures the central semantics that underlies the scientific processes of clinical research and can serve as an informatics foundation for supporting the entire range of knowledge activities that constitute the science of clinical research. PMID:24239612

Orthodontic treatment in periodontitis‐susceptible subjects: a systematic literature review

PubMed Central

Lindsten, Rune; Slotte, Christer; Bjerklin, Krister

2016-01-01

Abstract The aim is to evaluate the literature for clinical scientific data on possible effects of orthodontic treatment on periodontal status in periodontitis‐susceptible subjects. A systematic literature review was performed on studies in English using PubMed, MEDLINE, and Cochrane Library central databases (1965‐2014). By manually searching reference lists of selected studies, we identified additional articles; then we searched these publications: Journal of Periodontology, Periodontology 2000, Journal of Clinical Periodontology, American Journal of Orthodontics and Dentofacial Orthopedics, Angle Orthodontist, International Journal of Periodontics & Restorative Dentistry, and European Journal of Orthodontics. Search terms included randomized clinical trials, controlled clinical trials, prospective and retrospective clinical studies, case series >5 patients, periodontitis, orthodontics, alveolar bone loss, tooth migration, tooth movement, orthodontic extrusion, and orthodontic intrusion. Only studies on orthodontic treatment in periodontally compromised dentitions were included. One randomized controlled clinical trial, one controlled clinical trial, and 12 clinical studies were included. No evidence currently exists from controlled studies and randomized controlled clinical trials, which shows that orthodontic treatment improves or aggravates the status of periodontally compromised dentitions. PMID:29744163

Common Filing Deficiencies in Abbreviated New Drug Applications Containing Clinical Endpoint Studies.

PubMed

Fermaglich, Lewis J; Chen, Ru; Kim, Carol Y; Chuh, Eunjung Esther; Thomas, Teena; Shetty, Daiva; Lee, Julia; Young, Johnny; Fan, Ying

2018-01-01

The objective of this report is to summarize common deficiencies identified in the filing reviews of abbreviated new drug applications (ANDAs) with clinical endpoint bioequivalence studies and skin irritation, sensitization, and adhesion (I/S/A) studies received by the US Food and Drug Administration (FDA) between 2007 and 2017, to help applicants avoid common deficiencies, minimize "refuse-to-receive" (RTR) actions, "information requests," and ANDA approval delays. Multiple internal FDA databases were searched to evaluate and summarize common deficiencies identified in ANDA submissions containing clinical endpoint studies and skin I/S/A studies that required review by the Division of Clinical Review. A total of 275 ANDA submissions with filing reviews from January 2007 to June 2017 were analyzed in this report. Two hundred eighteen (79.3%) filing reviews contained one or more deficiencies. Seventy-nine (28.7%) ANDAs were issued RTR letters because of major clinical deficiencies, specifically bioequivalence and clinical deficiencies, accounting for 9% of overall identified deficiencies. Twenty-two other categories of deficiencies are summarized into 4 main categories: missing information related to the clinical studies other than data sets (38%), missing data sets (35%), formulation issues (12%), and organization/format issues (6%). The most common deficiency in the "missing information related to the clinical studies other than data sets" category was "missing clarification of information" (22%). We also noted that the Division of Filing Review has identified these same types of deficiencies since assuming responsibility of the filing assessment for ANDAs with clinical endpoint BE studies and skin I/S/A studies. In conclusion, to minimize "refuse-to-receive" actions, "information requests," and approval of ANDA delays for generic drug products, applicants should submit full clinical study reports, including all data sets for drug products recommending clinical studies.

A Study of Clinically Related Open Source Software Projects

PubMed Central

Hogarth, Michael A.; Turner, Stuart

2005-01-01

Open source software development has recently gained significant interest due to several successful mainstream open source projects. This methodology has been proposed as being similarly viable and beneficial in the clinical application domain as well. However, the clinical software development venue differs significantly from the mainstream software venue. Existing clinical open source projects have not been well characterized nor formally studied so the ‘fit’ of open source in this domain is largely unknown. In order to better understand the open source movement in the clinical application domain, we undertook a study of existing open source clinical projects. In this study we sought to characterize and classify existing clinical open source projects and to determine metrics for their viability. This study revealed several findings which we believe could guide the healthcare community in its quest for successful open source clinical software projects. PMID:16779056

Common pitfalls in statistical analysis: Clinical versus statistical significance

PubMed Central

Ranganathan, Priya; Pramesh, C. S.; Buyse, Marc

2015-01-01

In clinical research, study results, which are statistically significant are often interpreted as being clinically important. While statistical significance indicates the reliability of the study results, clinical significance reflects its impact on clinical practice. The third article in this series exploring pitfalls in statistical analysis clarifies the importance of differentiating between statistical significance and clinical significance. PMID:26229754

Challenges in translating endpoints from trials to observational cohort studies in oncology

PubMed Central

Ording, Anne Gulbech; Cronin-Fenton, Deirdre; Ehrenstein, Vera; Lash, Timothy L; Acquavella, John; Rørth, Mikael; Sørensen, Henrik Toft

2016-01-01

Clinical trials are considered the gold standard for examining drug efficacy and for approval of new drugs. Medical databases and population surveillance registries are valuable resources for post-approval observational research, which are increasingly used in studies of benefits and risk of new cancer drugs. Here, we address the challenges in translating endpoints from oncology trials to observational studies. Registry-based cohort studies can investigate real-world safety issues – including previously unrecognized concerns – by examining rare endpoints or multiple endpoints at once. In contrast to clinical trials, observational cohort studies typically do not exclude real-world patients from clinical practice, such as old and frail patients with comorbidity. The observational cohort study complements the clinical trial by examining the effectiveness of interventions applied in clinical practice and by providing evidence on long-term clinical outcomes, which are often not feasible to study in a clinical trial. Various endpoints can be included in clinical trials, such as hard endpoints, soft endpoints, surrogate endpoints, and patient-reported endpoints. Each endpoint has it strengths and limitations for use in research studies. Endpoints used in oncology trials are often not applicable in observational cohort studies which are limited by the setting of standard clinical practice and by non-standardized endpoint determination. Observational studies can be more helpful moving research forward if they restrict focus to appropriate and valid endpoints. PMID:27354827

Clinical relevance vs. statistical significance: Using neck outcomes in patients with temporomandibular disorders as an example.

PubMed

Armijo-Olivo, Susan; Warren, Sharon; Fuentes, Jorge; Magee, David J

2011-12-01

Statistical significance has been used extensively to evaluate the results of research studies. Nevertheless, it offers only limited information to clinicians. The assessment of clinical relevance can facilitate the interpretation of the research results into clinical practice. The objective of this study was to explore different methods to evaluate the clinical relevance of the results using a cross-sectional study as an example comparing different neck outcomes between subjects with temporomandibular disorders and healthy controls. Subjects were compared for head and cervical posture, maximal cervical muscle strength, endurance of the cervical flexor and extensor muscles, and electromyographic activity of the cervical flexor muscles during the CranioCervical Flexion Test (CCFT). The evaluation of clinical relevance of the results was performed based on the effect size (ES), minimal important difference (MID), and clinical judgement. The results of this study show that it is possible to have statistical significance without having clinical relevance, to have both statistical significance and clinical relevance, to have clinical relevance without having statistical significance, or to have neither statistical significance nor clinical relevance. The evaluation of clinical relevance in clinical research is crucial to simplify the transfer of knowledge from research into practice. Clinical researchers should present the clinical relevance of their results. Copyright © 2011 Elsevier Ltd. All rights reserved.

Use of platelet-rich plasma in the treatment of rotator cuff pathology. What has been scientifically proven?

PubMed

Miranda, I; Sánchez-Alepuz, E; Lucas, F J; Carratalá, V; González-Jofre, C A

To analyze the current scientific and/or clinical evidence supporting the use of platelet-rich plasma (PRP) in the treatment of rotator cuff pathology. After a systematic review in PubMed, studies assessing PRP efficacy in the treatment of rotator cuff pathology published since 2013 to date were identified. Data were grouped based on type of study (laboratory, clinical or meta-analysis); accordingly study design, pathology treated and clinical outcomes were summarized. Thirty five articles have been analyzed: 10 laboratory studies, 17 clinical assays and 8 meta-analyses. While laboratory studies report positive or partially positive results for the use of PRP, 70.6% of clinical studies and 75% of meta-analysis found no statistically significant differences between the PRP group and the control group. The positive results of laboratory studies do not translate well to clinical practice. There is no concordance among the few positive results reported in the clinical studies, and even some contradictory effects have been reported. There is no solid scientific and/or clinical evidence supporting the use of PRP in the treatment of rotator cuff pathology in routine clinical practice. Copyright © 2017 SECOT. Publicado por Elsevier España, S.L.U. All rights reserved.

Exploring the screening capacity of the Fear of Cancer Recurrence Inventory-Short Form for clinical levels of fear of cancer recurrence.

PubMed

Fardell, Joanna E; Jones, Georden; Smith, Allan Ben; Lebel, Sophie; Thewes, Belinda; Costa, Daniel; Tiller, Kerry; Simard, Sébastien; Feldstain, Andrea; Beattie, Sara; McCallum, Megan; Butow, Phyllis

2018-02-01

Fear of cancer recurrence (FCR) is a common concern among cancer survivors. Identifying survivors with clinically significant FCR requires validated screening measures and clinical cut-offs. We evaluated the Fear of Cancer Recurrence Inventory-Short Form (FCRI-SF) clinical cut-off in 2 samples. Level of FCR in study 1 participants (from an Australian randomized controlled trial: ConquerFear) was compared with FCRI-SF scores. Based on a biopsychosocial interview, clinicians rated participants as having nonclinical, subclinical, or clinical FCR. Study 2 participants (from a Canadian FCRI-English validation study) were classified as having clinical or nonclinical FCR by using the semistructured clinical interview for FCR (SIFCR). Receiver operating characteristic analyses evaluated the screening ability of the FCRI-SF against clinician ratings (study 1) and the SIFCR (study 2). In study 1, 167 cancer survivors (mean age: 53 years, SD = 10.1) participated. Clinicians rated 43% as having clinical FCR. In study 2, 40 cancer survivors (mean age: 68 years, SD = 7.0) participated; 25% met criteria for clinical FCR according to the SIFCR. For both studies 1 and 2, receiver operating characteristic analyses suggested a cut-off ≥22 on the FCRI-SF identified cancer survivors with clinical levels of FCR with adequate sensitivity and specificity. Establishing clinical cut-offs on FCR screening measures is crucial to tailoring individual care and conducting rigorous research. Our results suggest using a higher cut-off on the FCRI-SF than previously reported to identify clinically significant FCR. Continued evaluation and validation of the FCRI-SF cut-off is required across diverse cancer populations. Copyright © 2017 John Wiley & Sons, Ltd.

Out of sight, out of mind? Does terminating the physical presence of a geriatric consultant in the community clinic reduce the implementation rate for geriatric recommendations.

PubMed

Freud, Tamar; Punchik, Boris; Biderman, Aya; Peleg, Roni; Kagan, Ella; Barzak, Alex; Press, Yan

2016-01-01

To assess the effect of moving the geriatric consultation from the primary care clinic to another setting, on the rate of implementation of geriatric recommendations by family physicians. A retrospective review of the computerized medical records of elderly patients in four primary care clinics. The rate of implementation of geriatric recommendations was compared between clinics in which a geriatric consultant was physically present (control clinics) and a clinic where the consultation took place elsewhere (study clinic). In addition, the results of the present study were compared to a previous study in which the geriatric consultation was carried out in the study clinic and the family doctor was an active participant. 127 computerized files were reviewed in the study clinic and 133 in the control clinics. The mean age of the patients was 81.1±6.3 years and 63.1% were women. The overall implementation of geriatric recommendations by family doctors in the study clinic was 55.9%, a statistically significant decrease compared to the previous study where the rate was 73.9% (p<0.0001). In contrast, there was no change in the implementation rate in the control clinics at 65.0% in the present study and 59.9% in the previous one (p=0.205). Direct, person-to-person contact between the geriatric consultant and the family doctor has a beneficial effect on the implementation of geriatric recommendations. This should be considered by healthcare policy makers when planning geriatric services in the community. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Use of Statins to Augment Progenitor Cell Function in Preclinical and Clinical Studies of Regenerative Therapy: a Systematic Review.

PubMed

Park, Angela; Barrera-Ramirez, Juliana; Ranasinghe, Indee; Pilon, Sophie; Sy, Richmond; Fergusson, Dean; Allan, David S

2016-06-01

Mesenchymal stromal cells (MSCs) and endothelial progenitor cells (EPCs) are used in cell-based regenerative therapy. HMG CoA reductase inhibitors (statins) appear promising in blocking apoptosis, prolonging progenitor cell survival and improving their capacity to repair organ function. We performed a systematic review of preclinical and clinical studies to clarify whether statins can improve cell-based repair of organ injury. MEDLINE, EMBASE, and PUBMED databases were searched (1947 to June 25, 2013). Controlled clinical and pre-clinical studies were included that evaluated statin therapy used alone or in combination with MSCs or EPCs in patients or animals with organ injury. After screening 771 citations, 100 records underwent full eligibility screening of which 38 studies met eligibility and were included in the review: Studies were grouped into pre-clinical studies that involved statin treatment in combination with cell therapy (18 studies), preclinical studies of statin therapy alone (13 studies) and clinical studies of statin therapy (7 studies). Studies addressed cardiac injury (14 studies), vascular disorders (15 studies), neurologic conditions (8 studies) and bone fractures (1 study). Pre-clinical studies of statins in combination with MSC infusion (15 studies) or EPC therapy (3 studies) were described and despite marked heterogeneity in reporting outcomes of cellular analysis and organ function, all of these cell-based pre-clinical studies reported improved organ recovery with the addition of statin therapy. Moreover, 13 pre-clinical studies involved the administration of a statin drug alone to animals. An increase in EPC number and/or function (no studies of MSCs) was reported in 11 of these studies (85 %) and improved organ function in 12 studies (92 %). We also identified 7 clinical studies and none involved the administration of cells but described an increased number and/or function of EPCs (no studies of MSCs) and improved organ function with statin therapy (1.2-fold to 35-fold improvement over controls) in all 7 studies. Our systematic review provides a foundation of encouraging results that support further study of statins in regenerative therapy to augment the number and/or function of MSCs used in cell-based repair and to augment the number and function of EPCs in vivo to repair damaged tissues. Larger studies are needed to ensure safety and confirm clinical benefits.

Non-clinical studies in the process of new drug development - Part II: Good laboratory practice, metabolism, pharmacokinetics, safety and dose translation to clinical studies.

PubMed

Andrade, E L; Bento, A F; Cavalli, J; Oliveira, S K; Schwanke, R C; Siqueira, J M; Freitas, C S; Marcon, R; Calixto, J B

2016-12-12

The process of drug development involves non-clinical and clinical studies. Non-clinical studies are conducted using different protocols including animal studies, which mostly follow the Good Laboratory Practice (GLP) regulations. During the early pre-clinical development process, also known as Go/No-Go decision, a drug candidate needs to pass through several steps, such as determination of drug availability (studies on pharmacokinetics), absorption, distribution, metabolism and elimination (ADME) and preliminary studies that aim to investigate the candidate safety including genotoxicity, mutagenicity, safety pharmacology and general toxicology. These preliminary studies generally do not need to comply with GLP regulations. These studies aim at investigating the drug safety to obtain the first information about its tolerability in different systems that are relevant for further decisions. There are, however, other studies that should be performed according to GLP standards and are mandatory for the safe exposure to humans, such as repeated dose toxicity, genotoxicity and safety pharmacology. These studies must be conducted before the Investigational New Drug (IND) application. The package of non-clinical studies should cover all information needed for the safe transposition of drugs from animals to humans, generally based on the non-observed adverse effect level (NOAEL) obtained from general toxicity studies. After IND approval, other GLP experiments for the evaluation of chronic toxicity, reproductive and developmental toxicity, carcinogenicity and genotoxicity, are carried out during the clinical phase of development. However, the necessity of performing such studies depends on the new drug clinical application purpose.

Using Clinical Gait Case Studies to Enhance Learning in Biomechanics

ERIC Educational Resources Information Center

Chester, Victoria

2011-01-01

Clinical case studies facilitate the development of clinical reasoning strategies through knowledge and integration of the basic sciences. Case studies have been shown to be more effective in developing problem-solving abilities than the traditional lecture format. To enhance the learning experiences of students in biomechanics, clinical case…

The utility of observational studies in clinical decision making: lessons learned from statin trials.

PubMed

Foody, JoAnne M; Mendys, Phillip M; Liu, Larry Z; Simpson, Ross J

2010-05-01

Contemporary clinical decision making is well supported by a wide variety of information sources, including clinical practice guidelines, position papers, and insights from randomized controlled trials (RCTs). Much of our fundamental understanding of cardiovascular risk factors is based on multiple observations from major epidemiologic studies, such as The Seven Country Studies and the US-based Framingham Heart Study. These studies provided the framework for the development of clinical practice guidelines, including the National Cholesterol Education Program Adult Treatment Panel series. The objective of this article is to highlight the value of observational studies as a complement to clinical trial data for clinical decision making in real-world practice. Although RCTs are still the benchmark for assessing clinical efficacy and safety of a specific therapeutic approach, they may be of limited utility to practitioners who must then adapt the lessons learned from the trial into the patient care environment. The use of well-structured observational studies can improve our understanding of the translation of clinical trials into clinical practice, as demonstrated here with the example of statins. Although such studies have their own limitations, improved techniques for design and analysis have reduced the impact of bias and confounders. The introduction of the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) guidelines has provided more uniformity for such studies. When used together with RCTs, observational studies can enhance our understanding of effectiveness and utility in real-world clinical practice. In the examples of statin observational studies, the results suggest that relative effectiveness of different statins and potential impact of switching statins should be carefully considered in treating individual patients by practicing physicians.

A pragmatic method for transforming clinical research data from the research electronic data capture "REDCap" to Clinical Data Interchange Standards Consortium (CDISC) Study Data Tabulation Model (SDTM): Development and evaluation of REDCap2SDTM.

PubMed

Yamamoto, Keiichi; Ota, Keiko; Akiya, Ippei; Shintani, Ayumi

2017-06-01

The Clinical Data Interchange Standards Consortium (CDISC) Study Data Tabulation Model (SDTM) can be used for new drug application studies as well as secondarily for creating a clinical research data warehouse to leverage clinical research study data across studies conducted within the same disease area. However, currently not all clinical research uses Clinical Data Acquisition Standards Harmonization (CDASH) beginning in the set-up phase of the study. Once already initiated, clinical studies that have not utilized CDASH are difficult to map in the SDTM format. In addition, most electronic data capture (EDC) systems are not equipped to export data in SDTM format; therefore, in many cases, statistical software is used to generate SDTM datasets from accumulated clinical data. In order to facilitate efficient secondary use of accumulated clinical research data using SDTM, it is necessary to develop a new tool to enable mapping of information for SDTM, even during or after the clinical research. REDCap is an EDC system developed by Vanderbilt University and is used globally by over 2100 institutions across 108 countries. In this study, we developed a simulated clinical trial to evaluate a tool called REDCap2SDTM that maps information in the Field Annotation of REDCap to SDTM and executes data conversion, including when data must be pivoted to accommodate the SDTM format, dynamically, by parsing the mapping information using R. We confirmed that generating SDTM data and the define.xml file from REDCap using REDCap2SDTM was possible. Conventionally, generation of SDTM data and the define.xml file from EDC systems requires the creation of individual programs for each clinical study. However, our proposed method can be used to generate this data and file dynamically without programming because it only involves entering the mapping information into the Field Annotation, and additional data into specific files. Our proposed method is adaptable not only to new drug application studies but also to all types of research, including observational and public health studies. Our method is also adaptable to clinical data collected with CDASH at the beginning of a study in non-standard format. We believe that this tool will reduce the workload of new drug application studies and will support data sharing and reuse of clinical research data in academia. Copyright © 2017 Elsevier Inc. All rights reserved.

Building a semantic web-based metadata repository for facilitating detailed clinical modeling in cancer genome studies.

PubMed

Sharma, Deepak K; Solbrig, Harold R; Tao, Cui; Weng, Chunhua; Chute, Christopher G; Jiang, Guoqian

2017-06-05

Detailed Clinical Models (DCMs) have been regarded as the basis for retaining computable meaning when data are exchanged between heterogeneous computer systems. To better support clinical cancer data capturing and reporting, there is an emerging need to develop informatics solutions for standards-based clinical models in cancer study domains. The objective of the study is to develop and evaluate a cancer genome study metadata management system that serves as a key infrastructure in supporting clinical information modeling in cancer genome study domains. We leveraged a Semantic Web-based metadata repository enhanced with both ISO11179 metadata standard and Clinical Information Modeling Initiative (CIMI) Reference Model. We used the common data elements (CDEs) defined in The Cancer Genome Atlas (TCGA) data dictionary, and extracted the metadata of the CDEs using the NCI Cancer Data Standards Repository (caDSR) CDE dataset rendered in the Resource Description Framework (RDF). The ITEM/ITEM_GROUP pattern defined in the latest CIMI Reference Model is used to represent reusable model elements (mini-Archetypes). We produced a metadata repository with 38 clinical cancer genome study domains, comprising a rich collection of mini-Archetype pattern instances. We performed a case study of the domain "clinical pharmaceutical" in the TCGA data dictionary and demonstrated enriched data elements in the metadata repository are very useful in support of building detailed clinical models. Our informatics approach leveraging Semantic Web technologies provides an effective way to build a CIMI-compliant metadata repository that would facilitate the detailed clinical modeling to support use cases beyond TCGA in clinical cancer study domains.

Clinical Natural Language Processing in languages other than English: opportunities and challenges.

PubMed

Névéol, Aurélie; Dalianis, Hercules; Velupillai, Sumithra; Savova, Guergana; Zweigenbaum, Pierre

2018-03-30

Natural language processing applied to clinical text or aimed at a clinical outcome has been thriving in recent years. This paper offers the first broad overview of clinical Natural Language Processing (NLP) for languages other than English. Recent studies are summarized to offer insights and outline opportunities in this area. We envision three groups of intended readers: (1) NLP researchers leveraging experience gained in other languages, (2) NLP researchers faced with establishing clinical text processing in a language other than English, and (3) clinical informatics researchers and practitioners looking for resources in their languages in order to apply NLP techniques and tools to clinical practice and/or investigation. We review work in clinical NLP in languages other than English. We classify these studies into three groups: (i) studies describing the development of new NLP systems or components de novo, (ii) studies describing the adaptation of NLP architectures developed for English to another language, and (iii) studies focusing on a particular clinical application. We show the advantages and drawbacks of each method, and highlight the appropriate application context. Finally, we identify major challenges and opportunities that will affect the impact of NLP on clinical practice and public health studies in a context that encompasses English as well as other languages.

HIS-Based Support of Follow-Up Documentation – Concept and Implementation for Clinical Studies

PubMed Central

Herzberg, S.; Fritz, F.; Rahbar, K.; Stegger, L.; Schäfers, M.; Dugas, M.

2011-01-01

Objective Follow-up data must be collected according to the protocol of each clinical study, i.e. at certain time points. Missing follow-up information is a critical problem and may impede or bias the analysis of study data and result in delays. Moreover, additional patient recruitment may be necessary due to incomplete follow-up data. Current electronic data capture (EDC) systems in clinical studies are usually separated from hospital information systems (HIS) and therefore can provide limited functionality to support clinical workflow. In two case studies, we assessed the feasibility of HIS-based support of follow-up documentation. Methods We have developed a data model and a HIS-based workflow to provide follow-up forms according to clinical study protocols. If a follow-up form was due, a database procedure created a follow-up event which was translated by a communication server into an HL7 message and transferred to the import interface of the clinical information system (CIS). This procedure generated the required follow-up form and enqueued a link to it in a work list of the relating study nurses and study physicians, respectively. Results A HIS-based follow-up system automatically generated follow-up forms as defined by a clinical study protocol. These forms were scheduled into work lists of study nurses and study physicians. This system was integrated into the clinical workflow of two clinical studies. In a study from nuclear medicine, each scenario from the test concept according to the protocol of the single photon emission computer tomography/computer tomography (SPECT/CT) study was simulated and each scenario passed the test. For a study in psychiatry, 128 follow-up forms were automatically generated within 27 weeks, on average five forms per week (maximum 12, minimum 1 form per week). Conclusion HIS-based support of follow-up documentation in clinical studies is technically feasible and can support compliance with study protocols. PMID:23616857

Case studies on clinical evaluation of biosimilar monoclonal antibody: scientific considerations for regulatory approval.

PubMed

Kudrin, Alex; Knezevic, Ivana; Joung, Jeewon; Kang, Hye-Na

2015-01-01

The objective of this paper is to provide considerations based on comprehensive case studies important for regulatory evaluation of monoclonal antibodies as similar biotherapeutic products (SBPs) with a special emphasis on clinical aspects. Scientific principles from WHO Guidelines on SBPs were used as a basis for the exercise. Working groups consisted of regulators, manufacturers and academia. The following topics were discussed by the working groups: clinical criteria for biosimilarity, extrapolation approach and the overall regulatory decision making process. In order to determine typical pitfalls in the design of a SBP clinical programme and evaluate the gap of knowledge, amongst different industry and regulatory stakeholders on the appraisal of the data arising from SBP clinical studies, we have presented two fictional but realistic clinical case studies. The first case consists of the fictional development programme for an infliximab SBP candidate. The second case describes clinical studies proposed for a fictional rituximab SBP candidate. In the first scenario a highly similar quality profile has been taken forward into clinical studies whereas there was an important residual difference in functional attributes for the rituximab SBP candidate. These case studies were presented at the WHO implementation workshop for the WHO guidelines on evaluation of similar biotherapeutic products held in Seoul, Republic of Korea, in May 2014. The goal was to illustrate the interpretation of the clinical data arising from studies with SBP candidates and elicit knowledge gaps in clinical assessment. This paper reflects the outcome of the exercise and discussions held in Seoul and offers an analysis of the case studies as a learning opportunity on clinical development and evaluation of SBPs. Copyright © 2014 The International Alliance for Biological Standardization. Published by Elsevier Ltd. All rights reserved.

Preclinical to Clinical Translation of Studies of Transcranial Direct-Current Stimulation in the Treatment of Epilepsy: A Systematic Review

PubMed Central

Regner, Gabriela G.; Pereira, Patrícia; Leffa, Douglas T.; de Oliveira, Carla; Vercelino, Rafael; Fregni, Felipe; Torres, Iraci L. S.

2018-01-01

Epilepsy is a chronic brain syndrome characterized by recurrent seizures resulting from excessive neuronal discharges. Despite the development of various new antiepileptic drugs, many patients are refractory to treatment and report side effects. Non-invasive methods of brain stimulation, such as transcranial direct current stimulation (tDCS), have been tested as alternative approaches to directly modulate the excitability of epileptogenic neural circuits. Although some pilot and initial clinical studies have shown positive results, there is still uncertainty regarding the next steps of investigation in this field. Therefore, we reviewed preclinical and clinical studies using the following framework: (1) preclinical studies that have been successfully translated to clinical studies, (2) preclinical studies that have failed to be translated to clinical studies, and (3) clinical findings that were not previously tested in preclinical studies. We searched PubMed, Web of Science, Embase, and SciELO (2002–2017) using the keywords “tDCS,” “epilepsy,” “clinical trials,” and “animal models.” Our initial search resulted in 64 articles. After applying inclusion and exclusion criteria, we screened 17 full-text articles to extract findings about the efficacy of tDCS, with respect to the therapeutic framework used and the resulting reduction in seizures and epileptiform patterns. We found that few preclinical findings have been translated into clinical research (number of sessions and effects on seizure frequency) and that most findings have not been tested clinically (effects of tDCS on status epilepticus and absence epilepsy, neuroprotective effects in the hippocampus, and combined use with specific medications). Finally, considering that clinical studies on tDCS have been conducted for several epileptic syndromes, most were not previously tested in preclinical studies (Rasmussen's encephalitis, drug resistant epilepsy, and hippocampal sclerosis-induced epilepsy). Overall, most studies report positive findings. However, it is important to underscore that a successful preclinical study may not indicate success in a clinical study, considering the differences highlighted herein. Although most studies report significant findings, there are still important insights from preclinical work that must be tested clinically. Understanding these factors may improve the evidence for the potential use of this technique as a clinical tool in the treatment of epilepsy. PMID:29623027

Asking good clinical research questions and choosing the right study design.

PubMed

Bragge, P

2010-07-01

Clinicians and researchers seek answers to clinical research questions, primarily by accessing the results of clinical research studies. This paper moves the focus of research enquiry from getting answers to developing good clinical research questions. Using worked examples, the steps involved in refining questions drawn from various sources to create 'answerable' clinical research questions using the 'PICO' principle are described. Issues to consider in prioritising clinical research questions are also identified. Theoretical and practical considerations involved in choosing the right study design for a clinical research question are then discussed using the worked examples. These include: Copyright (c) 2010 Elsevier Ltd. All rights reserved.

Is There Value in Having Radiology Provide a Second Reading in Pediatric Orthopaedic Clinic?

PubMed

Natarajan, Vivek; Bosch, Patrick; Dede, Ozgur; Deeney, Vincent; Mendelson, Stephen; Ward, Timothy; Brooks, Maria; Kenkre, Tanya; Roach, James

2017-06-01

The Joint Commission on Accreditation of Healthcare Organizations specifically mandates the dual interpretation of musculoskeletal radiographs by a radiologist in addition to the orthopaedist in all hospital-based orthopaedic clinics. Previous studies have questioned the utility of this practice. The purpose of this study was to further investigate the clinical significance of having the radiologist provide a second interpretation in a hospital-based pediatric orthopaedic clinic. A retrospective review was performed of all patients who had plain radiographs obtained in the pediatric orthopaedic clinic at an academic children's hospital over a 4-month period. For each radiographic series, the orthopaedist's note and the radiology interpretation were reviewed and a determination was made of whether the radiology read provided new clinically useful information and/or a new diagnosis, whether it recommended further imaging, or if it missed a diagnosis that was reflected in the orthopaedist's note. The hospital charges associated with the radiology read for each study were also quantified. The charts of 1570 consecutive clinic patients who were seen in the pediatric orthopaedic clinic from January to April, 2012 were reviewed. There were 2509 radiographic studies performed, of which 2264 had both a documented orthopaedist's note and radiologist's read. The radiologist's interpretation added new, clinically important information in 1.0% (23/2264) of these studies. In 1.7% (38/2264) of the studies, it was determined that the radiologist missed the diagnosis or clinically important information that could affect treatment. The total amount of the professional fees charged for the radiologists' interpretations was $87,362. On average, the hospital charges for each occurrence in which the radiologist's read provided an additional diagnosis or clinically important information beyond the orthopaedist's note were $3798. The results of this study suggest that eliminating the requirement to have the radiologist interpret radiographs in the pediatric orthopaedic clinic would have few clinical consequences. Level III-This is a diagnostic retrospective cohort study.

Design Characteristics Influence Performance of Clinical Prediction Rules in Validation: A Meta-Epidemiological Study

PubMed Central

Ban, Jong-Wook; Emparanza, José Ignacio; Urreta, Iratxe; Burls, Amanda

2016-01-01

Background Many new clinical prediction rules are derived and validated. But the design and reporting quality of clinical prediction research has been less than optimal. We aimed to assess whether design characteristics of validation studies were associated with the overestimation of clinical prediction rules’ performance. We also aimed to evaluate whether validation studies clearly reported important methodological characteristics. Methods Electronic databases were searched for systematic reviews of clinical prediction rule studies published between 2006 and 2010. Data were extracted from the eligible validation studies included in the systematic reviews. A meta-analytic meta-epidemiological approach was used to assess the influence of design characteristics on predictive performance. From each validation study, it was assessed whether 7 design and 7 reporting characteristics were properly described. Results A total of 287 validation studies of clinical prediction rule were collected from 15 systematic reviews (31 meta-analyses). Validation studies using case-control design produced a summary diagnostic odds ratio (DOR) 2.2 times (95% CI: 1.2–4.3) larger than validation studies using cohort design and unclear design. When differential verification was used, the summary DOR was overestimated by twofold (95% CI: 1.2 -3.1) compared to complete, partial and unclear verification. The summary RDOR of validation studies with inadequate sample size was 1.9 (95% CI: 1.2 -3.1) compared to studies with adequate sample size. Study site, reliability, and clinical prediction rule was adequately described in 10.1%, 9.4%, and 7.0% of validation studies respectively. Conclusion Validation studies with design shortcomings may overestimate the performance of clinical prediction rules. The quality of reporting among studies validating clinical prediction rules needs to be improved. PMID:26730980

Design Characteristics Influence Performance of Clinical Prediction Rules in Validation: A Meta-Epidemiological Study.

PubMed

Ban, Jong-Wook; Emparanza, José Ignacio; Urreta, Iratxe; Burls, Amanda

2016-01-01

Many new clinical prediction rules are derived and validated. But the design and reporting quality of clinical prediction research has been less than optimal. We aimed to assess whether design characteristics of validation studies were associated with the overestimation of clinical prediction rules' performance. We also aimed to evaluate whether validation studies clearly reported important methodological characteristics. Electronic databases were searched for systematic reviews of clinical prediction rule studies published between 2006 and 2010. Data were extracted from the eligible validation studies included in the systematic reviews. A meta-analytic meta-epidemiological approach was used to assess the influence of design characteristics on predictive performance. From each validation study, it was assessed whether 7 design and 7 reporting characteristics were properly described. A total of 287 validation studies of clinical prediction rule were collected from 15 systematic reviews (31 meta-analyses). Validation studies using case-control design produced a summary diagnostic odds ratio (DOR) 2.2 times (95% CI: 1.2-4.3) larger than validation studies using cohort design and unclear design. When differential verification was used, the summary DOR was overestimated by twofold (95% CI: 1.2 -3.1) compared to complete, partial and unclear verification. The summary RDOR of validation studies with inadequate sample size was 1.9 (95% CI: 1.2 -3.1) compared to studies with adequate sample size. Study site, reliability, and clinical prediction rule was adequately described in 10.1%, 9.4%, and 7.0% of validation studies respectively. Validation studies with design shortcomings may overestimate the performance of clinical prediction rules. The quality of reporting among studies validating clinical prediction rules needs to be improved.

Health literacy and usability of clinical trial search engines.

PubMed

Utami, Dina; Bickmore, Timothy W; Barry, Barbara; Paasche-Orlow, Michael K

2014-01-01

Several web-based search engines have been developed to assist individuals to find clinical trials for which they may be interested in volunteering. However, these search engines may be difficult for individuals with low health and computer literacy to navigate. The authors present findings from a usability evaluation of clinical trial search tools with 41 participants across the health and computer literacy spectrum. The study consisted of 3 parts: (a) a usability study of an existing web-based clinical trial search tool; (b) a usability study of a keyword-based clinical trial search tool; and (c) an exploratory study investigating users' information needs when deciding among 2 or more candidate clinical trials. From the first 2 studies, the authors found that users with low health literacy have difficulty forming queries using keywords and have significantly more difficulty using a standard web-based clinical trial search tool compared with users with adequate health literacy. From the third study, the authors identified the search factors most important to individuals searching for clinical trials and how these varied by health literacy level.

Nursing students' perspectives on clinical instructors' effective teaching strategies: A descriptive study.

PubMed

Valiee, Sina; Moridi, Glorokh; Khaledi, Shahnaz; Garibi, Fardin

2016-01-01

An important factor contributing to the quality of clinical education is instructors' teaching performance. The aim of this study was to identify clinical instructors' most effective teaching strategies from nursing and midwifery students' perspectives. This was a descriptive cross-sectional study. All third- and fourth-year bachelor's nursing and midwifery students studying at the Nursing and Midwifery Faculty of Kurdistan University of Medical Sciences were recruited to the study by using the census method. The study instrument consisted of a demographic questionnaire and the self-report 30-item Clinical Instructors' Effective Teaching Strategies Inventory. The SPSS v.16.0 was used for data analysis. The most effective teaching strategies of clinical instructors from nursing and midwifery students' perspectives were respectively 'treating students, clients, and colleagues with respect' and 'being eager for guiding students and manage their problems'. Clinical instructors need to be eager for education and also be able to establish effective communication with students. Empowering clinical instructors in specialized and technical aspects of clinical education seems necessary. Copyright © 2015 Elsevier Ltd. All rights reserved.

Student's perceptions of effective clinical teaching revisited.

PubMed

Kelly, Claudette

2007-11-01

Despite a wealth of research on clinical teaching, the criteria for determining what constitutes effective clinical teaching remain poorly defined [Cholowski, K., 2002. Nursing students' and clinical educators' perceptions of characteristics of effective clinical educators in an Australian university school of nursing. Journal of Advanced Nursing 39 (5), 412-420]. This paper reports on two studies exploring second and third year nursing student's perceptions of effective clinical teaching over 14 years (1989-2003). The aim of the inquiry was to compare student's perceptions in diploma and baccalaureate programs within existing clinical contexts. This research used a generative approach to elicit learner's views of what teacher characteristics and contextual influences impact them in clinical settings. A convenience sample of 30 students at the end of second and third years volunteered to be interviewed in-depth for each study. The first study was conducted in a diploma program, whereas in the second study all but a few students were elected to complete a four year baccalaureate nursing degree. Findings from both studies are remarkably consistent. Students in both studies rated teacher knowledge as most important followed by feedback and communication skills. Teacher knowledge appeared critical in four areas: as it pertains to the clinical setting, the curriculum, the learner and teaching/learning theory. How well students perceived that they were accepted by staff, student-teacher ratios and peer support also appeared to impact student's views of effective clinical teaching. This research has implications for employment and evaluation practices for teachers in applied fields such as nursing. The study raises questions about the recent trend toward temporary employment of clinical teachers and in the separation of academic and clinical roles of nurse educators.

A multicenter study: how do medical students perceive clinical learning climate?

PubMed

Yilmaz, Nilufer Demiral; Velipasaoglu, Serpil; Ozan, Sema; Basusta, Bilge Uzun; Midik, Ozlem; Mamakli, Sumer; Karaoglu, Nazan; Tengiz, Funda; Durak, Halil İbrahim; Sahin, Hatice

2016-01-01

The relationship between students and instructors is of crucial importance for the development of a positive learning climate. Learning climate is a multifaceted concept, and its measurement is a complicated process. The aim of this cross-sectional study was to determine medical students' perceptions about the clinical learning climate and to investigate differences in their perceptions in terms of various variables. Medical students studying at six medical schools in Turkey were recruited for the study. All students who completed clinical rotations, which lasted for 3 or more weeks, were included in the study (n=3,097). Data were collected using the Clinical Learning Climate Scale (CLCS). The CLCS (36 items) includes three subscales: clinical environment, emotion, and motivation. Each item is scored using a 5-point Likert scale (1: strongly disagree to 5: strongly agree). The response rate for the trainees was 69.67% (n=1,519), and for the interns it was 51.47% (n=917). The mean total CLCS score was 117.20±17.19. The rotation during which the clinical learning climate was perceived most favorably was the Physical Therapy and Rehabilitation rotation (mean score: 137.77). The most negatively perceived rotation was the General Internal Medicine rotation (mean score: 104.31). There were significant differences between mean total scores in terms of trainee/intern characteristics, internal medicine/surgical medicine rotations, and perception of success. The results of this study drew attention to certain aspects of the clinical learning climate in medical schools. Clinical teacher/instructor/supervisor, clinical training programs, students' interactions in clinical settings, self-realization, mood, students' intrinsic motivation, and institutional commitment are important components of the clinical learning climate. For this reason, the aforementioned components should be taken into consideration in studies aiming to improve clinical learning climate.

Developing an International Register of Clinical Prediction Rules for Use in Primary Care: A Descriptive Analysis

PubMed Central

Keogh, Claire; Wallace, Emma; O’Brien, Kirsty K.; Galvin, Rose; Smith, Susan M.; Lewis, Cliona; Cummins, Anthony; Cousins, Grainne; Dimitrov, Borislav D.; Fahey, Tom

2014-01-01

PURPOSE We describe the methodology used to create a register of clinical prediction rules relevant to primary care. We also summarize the rules included in the register according to various characteristics. METHODS To identify relevant articles, we searched the MEDLINE database (PubMed) for the years 1980 to 2009 and supplemented the results with searches of secondary sources (books on clinical prediction rules) and personal resources (eg, experts in the field). The rules described in relevant articles were classified according to their clinical domain, the stage of development, and the clinical setting in which they were studied. RESULTS Our search identified clinical prediction rules reported between 1965 and 2009. The largest share of rules (37.2%) were retrieved from PubMed. The number of published rules increased substantially over the study decades. We included 745 articles in the register; many contained more than 1 clinical prediction rule study (eg, both a derivation study and a validation study), resulting in 989 individual studies. In all, 434 unique rules had gone through derivation; however, only 54.8% had been validated and merely 2.8% had undergone analysis of their impact on either the process or outcome of clinical care. The rules most commonly pertained to cardiovascular disease, respiratory, and musculoskeletal conditions. They had most often been studied in the primary care or emergency department settings. CONCLUSIONS Many clinical prediction rules have been derived, but only about half have been validated and few have been assessed for clinical impact. This lack of thorough evaluation for many rules makes it difficult to retrieve and identify those that are ready for use at the point of patient care. We plan to develop an international web-based register of clinical prediction rules and computer-based clinical decision support systems. PMID:25024245

A multicenter study: how do medical students perceive clinical learning climate?

PubMed

Yilmaz, Nilufer Demiral; Velipasaoglu, Serpil; Ozan, Sema; Basusta, Bilge Uzun; Midik, Ozlem; Mamakli, Sumer; Karaoglu, Nazan; Tengiz, Funda; Durak, Halil İbrahim; Sahin, Hatice

2016-01-01

Background The relationship between students and instructors is of crucial importance for the development of a positive learning climate. Learning climate is a multifaceted concept, and its measurement is a complicated process. The aim of this cross-sectional study was to determine medical students' perceptions about the clinical learning climate and to investigate differences in their perceptions in terms of various variables. Methods Medical students studying at six medical schools in Turkey were recruited for the study. All students who completed clinical rotations, which lasted for 3 or more weeks, were included in the study (n=3,097). Data were collected using the Clinical Learning Climate Scale (CLCS). The CLCS (36 items) includes three subscales: clinical environment, emotion, and motivation. Each item is scored using a 5-point Likert scale (1: strongly disagree to 5: strongly agree). Results The response rate for the trainees was 69.67% (n=1,519), and for the interns it was 51.47% (n=917). The mean total CLCS score was 117.20±17.19. The rotation during which the clinical learning climate was perceived most favorably was the Physical Therapy and Rehabilitation rotation (mean score: 137.77). The most negatively perceived rotation was the General Internal Medicine rotation (mean score: 104.31). There were significant differences between mean total scores in terms of trainee/intern characteristics, internal medicine/surgical medicine rotations, and perception of success. Conclusion The results of this study drew attention to certain aspects of the clinical learning climate in medical schools. Clinical teacher/instructor/supervisor, clinical training programs, students' interactions in clinical settings, self-realization, mood, students' intrinsic motivation, and institutional commitment are important components of the clinical learning climate. For this reason, the aforementioned components should be taken into consideration in studies aiming to improve clinical learning climate.

A Feasibility Study of a Web Based Performance Improvement System for Substance Abuse Treatment Providers

PubMed Central

Forman, Robert; Crits-Christoph, Paul; Kaynak, Övgü; Worley, Matt; Hantula, Donald A.; Kulaga, Agatha; Rotrosen, John; Chu, Melissa; Gallop, Robert; Potter, Jennifer; Muchowski, Patrice; Brower, Kirk; Strobbe, Stephen; Magruder, Kathy; Chellis, A’Delle H.; Clodfelter, Tad; Cawley, Margaret

2007-01-01

We report here on the feasibility of implementing a semi-automated performance improvement system - Patient Feedback (PF) - that enables real-time monitoring of patient ratings of therapeutic alliance, treatment satisfaction, and drug/alcohol use in outpatient substance abuse treatment clinics. The study was conducted in 6 clinics within the National Institute on Drug Abuse Clinical Trials Network. It involved a total of thirty-nine clinicians and 6 clinic supervisors. Throughout the course of the study (4 week training period, 4 week baseline, 12 week intervention, 4 week post-intervention assessment, 1 year sustainability phase) there was an overall collection rate of 75.5% of the clinic patient census. In general, the clinicians in these clinics had very positive treatment satisfaction and alliance ratings throughout the study. However, one clinic had worse drug use scores at baseline than other participating clinics, and showed a decrease in self-reported drug use at post-intervention. Although the implementation of the PF system proved to be feasible in actual clinical settings, further modifications of the PF system are needed to enhance any potential clinical usefulness. PMID:17499954

The distribution of outcomes research papers across clinical journals.

PubMed

Goldsack, Jennifer; McLaughlin, Chris; Bristol, Mirar N; Loeb, Alex; Bergey, Meredith; Sonnad, Seema S

2011-06-01

This study examines the distribution of health outcomes research (HOR) studies in the clinical literature by clinical areas and journal impact factor. The authors reviewed 535 journals and divided the sample into higher and lower impact journals across four clinical area. Mann-Whitney and Kruskal-Wallis tests were used to examine differences across four categories of outcomes research articles published, specifically the incidence of articles in higher versus lower impact journals and differences across clinical areas. All high-impact journals published more safety and quality articles than process assessment, quality of life, or cost analysis studies. The number of each type of outcomes research study published was highly variable across all clinical areas. Only arthritis and outcomes research journals showed statistically significant differences between higher versus lower impact journals. Authors may benefit from considering these differences in their clinical specialty area when deciding where to submit HOR studies.

Reporting Guidelines for Clinical Pharmacokinetic Studies: The ClinPK Statement.

PubMed

Kanji, Salmaan; Hayes, Meghan; Ling, Adam; Shamseer, Larissa; Chant, Clarence; Edwards, David J; Edwards, Scott; Ensom, Mary H H; Foster, David R; Hardy, Brian; Kiser, Tyree H; la Porte, Charles; Roberts, Jason A; Shulman, Rob; Walker, Scott; Zelenitsky, Sheryl; Moher, David

2015-07-01

Transparent reporting of all research is essential for assessing the validity of any study. Reporting guidelines are available and endorsed for many types of research but are lacking for clinical pharmacokinetic studies. Such tools promote the consistent reporting of a minimal set of information for end users, and facilitate knowledge translation of research. The objective of this study was to create a guideline to assist in the transparent and complete reporting of clinical pharmacokinetic studies. Preliminary content to be considered was identified from a systematic search of the literature and regulatory documents. Stakeholders were identified to participate in a modified Delphi exercise and a virtual meeting to generate consensus for items considered essential in the reporting of clinical pharmacokinetic studies. The proposed checklist was pilot tested on 100 recently published clinical pharmacokinetic studies. Overall and itemized compliance with the proposed guidance was determined for each study. Sixty-eight stakeholders from nine countries consented to participate. Four rounds of a modified Delphi survey and a series of small virtual meetings were required to generate consensus for a 24-item checklist considered to be essential to the reporting of clinical pharmacokinetic studies. When applied to the 100 most recently published clinical pharmacokinetic studies, 45 were determined to be compliant with at least 80 % of the checklist items. Explanatory text was prepared using examples of compliant reporting from these and other relevant studies. The reader's ability to judge the validity of pharmacokinetic research can be greatly compromised by the incomplete reporting of study information. Using consensus methods, we have developed a tool to guide transparent and accurate reporting of clinical pharmacokinetic studies. Endorsement and implementation of these guidelines by researchers, clinicians and journals would promote more consistent reporting of these studies and allow for better assessment of utility for clinical applications.

How physicians teach in the clinical setting: The embedded roles of teaching and clinical care.

PubMed

Steinert, Yvonne; Basi, Mandeep; Nugus, Peter

2017-12-01

Clinical teaching lies at the heart of medical education. However, few studies have explored the embedded nature of teaching and clinical care. The goal of this study was to examine the process of clinical teaching as it naturally, and spontaneously, unfolds in a broad range of authentic contexts with medical students and residents. This focused ethnographic study consisted of 160 hours of participant observation and field interviews with three internal medicine teams. Thematic analysis guided data organization and interpretation. Three overlapping themes emerged: the interconnectedness between clinical work and pedagogy; a multiplicity of teachers; and the influence of space and artifacts on teaching and learning. Clinical teaching, which was deeply embedded in clinical care, was influenced by the acuity of patient problems, learner needs, and the context in which teaching unfolded; it also occurred on a spectrum that included planned, opportunistic, formal, and informal teaching (and learning). Study findings suggest that clinical teaching, which is marked by an intersection between service and teaching, can be viewed as an example of work-based teaching. They also yield suggestions for the enhancement of clinical teaching in inpatient settings, faculty development, and educational policies that recognize clinical teaching and learning.

Enablers of and barriers to high quality clinical supervision among occupational therapists across Queensland in Australia: findings from a qualitative study.

PubMed

Martin, Priya; Kumar, Saravana; Lizarondo, Lucylynn; VanErp, Ans

2015-09-24

Health professionals practising in countries with dispersed populations such as Australia rely on clinical supervision for professional support. While there are directives and guidelines in place to govern clinical supervision, little is known about how it is actually conducted and what makes it effective. The purpose of this study was to explore the enablers of and barriers to high quality clinical supervision among occupational therapists across Queensland in Australia. This qualitative study took place as part of a broader project. Individual, in-depth, semi-structured interviews were conducted with occupational therapy supervisees in Queensland. The interviews explored the enablers of and barriers to high quality clinical supervision in this group. They further explored some findings from the initial quantitative study. Content analysis of the interview data resulted in eight themes. These themes were broadly around the importance of the supervisory relationship, the impact of clinical supervision and the enablers of and barriers to high quality clinical supervision. This study identified a number of factors that were perceived to be associated with high quality clinical supervision. Supervisor-supervisee matching and fit, supervisory relationship and availability of supervisor for support in between clinical supervision sessions appeared to be associated with perceptions of higher quality of clinical supervision received. Some face-to-face contact augmented with telesupervision was found to improve perceptions of the quality of clinical supervision received via telephone. Lastly, dual roles where clinical supervision and line management were provided by the same person were not considered desirable by supervisees. A number of enablers of and barriers to high quality clinical supervision were also identified. With clinical supervision gaining increasing prominence as part of organisational and professional governance, this study provides important lessons for successful and sustainable clinical supervision in practice contexts.

Pediatric Clinical Trials Conducted in South Korea from 2006 to 2015: An Analysis of the South Korean Clinical Research Information Service, US ClinicalTrials.gov and European Clinical Trials Registries.

PubMed

Choi, Sheung-Nyoung; Lee, Ji-Hyun; Song, In-Kyung; Kim, Eun-Hee; Kim, Jin-Tae; Kim, Hee-Soo

2017-12-01

The status of pediatric clinical trials performed in South Korea in the last decade, including clinical trials of drugs with unapproved indications for children, has not been previously examined. The aim was to provide information regarding the current state of pediatric clinical trials and create a basis for future trials performed in South Korea by reviewing three databases of clinical trials registrations. We searched for pediatric clinical studies (participants <18 years old) conducted in South Korea between 2006 and 2015 registered on the Clinical Research Information Service (CRIS), ClinicalTrials.gov, and the European Clinical Trials Registry (EuCTR). Additionally, we reviewed whether unapproved indications were involved in each trial by comparing the trials with a list of authorized trials provided by the Ministry of Food and Drug Safety (MFDS). The primary and secondary outcomes were to determine the change in number of pediatric clinical trials with unapproved indications over time and to assess the status of unauthorized pediatric clinical trials from the MFDS and the publication of articles after these clinical trials, respectively. We identified 342 clinical studies registered in the CRIS (n = 81), ClinicalTrials.gov (n = 225), and EuCTR (n = 36), of which 306 were reviewed after excluding duplicate registrations. Among them, 181 studies were interventional trials dealing with drugs and biological agents, of which 129 (71.3%) involved unapproved drugs. Of these 129 trials, 107 (82.9%) were authorized by the MFDS. Pediatric clinical trials in South Korea aiming to establish the safety and efficacy of drugs in children are increasing; however, non-MFDS-authorized studies remain an issue.

78 FR 60291 - Investigational Device Exemptions for Early Feasibility Medical Device Clinical Studies...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-10-01

...] Investigational Device Exemptions for Early Feasibility Medical Device Clinical Studies, Including Certain First in Human Studies; Guidance for Industry and Food and Drug Administration Staff; Availability AGENCY... Feasibility Medical Device Clinical Studies, Including Certain First in Human (FIH) Studies.'' Through the...

Clinical reasoning of nursing students on clinical placement: Clinical educators' perceptions.

PubMed

Hunter, Sharyn; Arthur, Carol

2016-05-01

Graduate nurses may have knowledge and adequate clinical psychomotor skills however they have been identified as lacking the clinical reasoning skills to deliver safe, effective care suggesting contemporary educational approaches do not always facilitate the development of nursing students' clinical reasoning. While nursing literature explicates the concept of clinical reasoning and develops models that demonstrate clinical reasoning, there is very little published about nursing students and clinical reasoning during clinical placements. Semi-structured interviews were conducted with ten clinical educators to gain an understanding of how they recognised, developed and appraised nursing students' clinical reasoning while on clinical placement. This study found variability in the clinical educators' conceptualisation, recognition, and facilitation of students' clinical reasoning. Although most of the clinical educators conceptualised clinical reasoning as a process those who did not demonstrated the greatest variability in the recognition and facilitation of students' clinical reasoning. The clinical educators in this study also described being unable to adequately appraise a student's clinical reasoning during clinical placement with the use of the current performance assessment tool. Copyright © 2016 Elsevier Ltd. All rights reserved.

How can we improve clinical research in pneumonia?

PubMed

Ramirez, Julio A

2018-05-01

The primary challenges in the field of clinical research include a lack of support within existing infrastructure, insufficient number of clinical research training programs and a paucity of qualified mentors. Most medical centers offer infrastructure support for investigators working with industry sponsors or government-funded clinical trials, yet there are a significant amount of clinical studies performed in the field of pneumonia which are observational studies. For this type of research, which is frequently unfunded, support is usually lacking. In an attempt to optimize clinical research in pneumonia, at the University of Louisville, we developed a clinical research coordinating center (CRCC). The center manages clinical studies in the field of respiratory infections, with the primary focus being pneumonia. Other activities of the CRCC include the organization of an annual clinical research training course for physicians and other healthcare workers, and the facilitation of international research mentoring by a process of connecting new pneumonia investigators with established clinical investigators. To improve clinical research in pneumonia, institutions need to have the appropriate infrastructure in place to support investigators in all aspects of the clinical research process.

Enhancing the Alignment of the Preclinical and Clinical Stroke Recovery Research Pipeline: Consensus-Based Core Recommendations From the Stroke Recovery and Rehabilitation Roundtable Translational Working Group.

PubMed

Corbett, Dale; Carmichael, S Thomas; Murphy, Timothy H; Jones, Theresa A; Schwab, Martin E; Jolkkonen, Jukka; Clarkson, Andrew N; Dancause, Numa; Weiloch, Tadeusz; Johansen-Berg, Heidi; Nilsson, Michael; McCullough, Louise D; Joy, Mary T

2017-08-01

Stroke recovery research involves distinct biological and clinical targets compared to the study of acute stroke. Guidelines are proposed for the pre-clinical modeling of stroke recovery and for the alignment of pre-clinical studies to clinical trials in stroke recovery.

Clinical studies of the Research Committee on Intractable Vasculitides, the Ministry of Health, Labour and Welfare of Japan.

PubMed

Makino, Hirofumi; Sada, Ken-Ei

2013-10-01

In Japan, the Research Committee on Intractable Vasculitides, supported by the Ministry of Health, Labour and Welfare, has been promoting basic and clinical research on vasculitis since 1972. The present Research Committee on Intractable Vasculitides comprises 4 subcommittees under the direction of a Principal Investigator: Basic and Pathological Research Subcommittee, Clinical Research Subcommittee of Small and Medium-sized Vessel Vasculitis, Clinical Research Subcommittee of Large-sized Vessel Vasculitis, and International Cooperation Research Subcommittee. Since 2008, 9 nationwide clinical studies for vasculitis have been conducted and 8 clinical and basic studies are in progress.

ClinicalCodes: an online clinical codes repository to improve the validity and reproducibility of research using electronic medical records.

PubMed

Springate, David A; Kontopantelis, Evangelos; Ashcroft, Darren M; Olier, Ivan; Parisi, Rosa; Chamapiwa, Edmore; Reeves, David

2014-01-01

Lists of clinical codes are the foundation for research undertaken using electronic medical records (EMRs). If clinical code lists are not available, reviewers are unable to determine the validity of research, full study replication is impossible, researchers are unable to make effective comparisons between studies, and the construction of new code lists is subject to much duplication of effort. Despite this, the publication of clinical codes is rarely if ever a requirement for obtaining grants, validating protocols, or publishing research. In a representative sample of 450 EMR primary research articles indexed on PubMed, we found that only 19 (5.1%) were accompanied by a full set of published clinical codes and 32 (8.6%) stated that code lists were available on request. To help address these problems, we have built an online repository where researchers using EMRs can upload and download lists of clinical codes. The repository will enable clinical researchers to better validate EMR studies, build on previous code lists and compare disease definitions across studies. It will also assist health informaticians in replicating database studies, tracking changes in disease definitions or clinical coding practice through time and sharing clinical code information across platforms and data sources as research objects.

ClinicalCodes: An Online Clinical Codes Repository to Improve the Validity and Reproducibility of Research Using Electronic Medical Records

PubMed Central

Springate, David A.; Kontopantelis, Evangelos; Ashcroft, Darren M.; Olier, Ivan; Parisi, Rosa; Chamapiwa, Edmore; Reeves, David

2014-01-01

Lists of clinical codes are the foundation for research undertaken using electronic medical records (EMRs). If clinical code lists are not available, reviewers are unable to determine the validity of research, full study replication is impossible, researchers are unable to make effective comparisons between studies, and the construction of new code lists is subject to much duplication of effort. Despite this, the publication of clinical codes is rarely if ever a requirement for obtaining grants, validating protocols, or publishing research. In a representative sample of 450 EMR primary research articles indexed on PubMed, we found that only 19 (5.1%) were accompanied by a full set of published clinical codes and 32 (8.6%) stated that code lists were available on request. To help address these problems, we have built an online repository where researchers using EMRs can upload and download lists of clinical codes. The repository will enable clinical researchers to better validate EMR studies, build on previous code lists and compare disease definitions across studies. It will also assist health informaticians in replicating database studies, tracking changes in disease definitions or clinical coding practice through time and sharing clinical code information across platforms and data sources as research objects. PMID:24941260

A systematic review of clinical assessment for undergraduate nursing students.

PubMed

Wu, Xi Vivien; Enskär, Karin; Lee, Cindy Ching Siang; Wang, Wenru

2015-02-01

Consolidated clinical practicum prepares pre-registration nursing students to function as beginning practitioners. The clinical competencies of final-year nursing students provide a key indication of professional standards of practice and patient safety. Thus, clinical assessment of nursing students is a crucial issue for educators and administrators. The aim of this systematic review was to explore the clinical competency assessment for undergraduate nursing students. PubMed, CINAHL, ScienceDirect, Web of Science, and EBSCO were systematically searched from January 2000 to December 2013. The systematic review was in line with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Published quantitative and qualitative studies that examined clinical assessment practices and tools used in clinical nursing education were retrieved. Quality assessment, data extraction, and analysis were completed on all included studies. This review screened 2073 titles, abstracts and full-text records, resulting in 33 included studies. Two reviewers assessed the quality of the included studies. Fourteen quantitative and qualitative studies were identified for this evaluation. The evidence was ordered into emergent themes; the overarching themes were current practices in clinical assessment, issues of learning and assessment, development of assessment tools, and reliability and validity of assessment tools. There is a need to develop a holistic clinical assessment tool with reasonable level of validity and reliability. Clinical assessment is a robust activity and requires collaboration between clinical partners and academia to enhance the clinical experiences of students, the professional development of preceptors, and the clinical credibility of academics. Copyright © 2014 Elsevier Ltd. All rights reserved.

The effects of clinical supervision on supervisees and patients in cognitive behavioral therapy: a systematic review.

PubMed

Alfonsson, Sven; Parling, Thomas; Spännargård, Åsa; Andersson, Gerhard; Lundgren, Tobias

2018-05-01

Clinical supervision is a central part of psychotherapist training but the empirical support for specific supervision theories or features is unclear. The aims of this study were to systematically review the empirical research literature regarding the effects of clinical supervision on therapists' competences and clinical outcomes within Cognitive Behavior Therapy (CBT). A comprehensive database search resulted in 4103 identified publications. Of these, 133 were scrutinized and in the end 5 studies were included in the review for data synthesis. The five studies were heterogeneous in scope and quality and only one provided firm empirical support for the positive effects of clinical supervision on therapists' competence. The remaining four studies suffered from methodological weaknesses, but provided some preliminary support that clinical supervision may be beneficiary for novice therapists. No study could show benefits from supervision for patients. The research literature suggests that clinical supervision may have some potential effects on novice therapists' competence compared to no supervision but the effects on clinical outcomes are still unclear. While bug-in-the-eye live supervision may be more effective than standard delayed supervision, the effects of specific supervision models or features are also unclear. There is a continued need for high-quality empirical studies on the effects of clinical supervision in psychotherapy.

The Database for Aggregate Analysis of ClinicalTrials.gov (AACT) and Subsequent Regrouping by Clinical Specialty

PubMed Central

Tasneem, Asba; Aberle, Laura; Ananth, Hari; Chakraborty, Swati; Chiswell, Karen; McCourt, Brian J.; Pietrobon, Ricardo

2012-01-01

Background The ClinicalTrials.gov registry provides information regarding characteristics of past, current, and planned clinical studies to patients, clinicians, and researchers; in addition, registry data are available for bulk download. However, issues related to data structure, nomenclature, and changes in data collection over time present challenges to the aggregate analysis and interpretation of these data in general and to the analysis of trials according to clinical specialty in particular. Improving usability of these data could enhance the utility of ClinicalTrials.gov as a research resource. Methods/Principal Results The purpose of our project was twofold. First, we sought to extend the usability of ClinicalTrials.gov for research purposes by developing a database for aggregate analysis of ClinicalTrials.gov (AACT) that contains data from the 96,346 clinical trials registered as of September 27, 2010. Second, we developed and validated a methodology for annotating studies by clinical specialty, using a custom taxonomy employing Medical Subject Heading (MeSH) terms applied by an NLM algorithm, as well as MeSH terms and other disease condition terms provided by study sponsors. Clinical specialists reviewed and annotated MeSH and non-MeSH disease condition terms, and an algorithm was created to classify studies into clinical specialties based on both MeSH and non-MeSH annotations. False positives and false negatives were evaluated by comparing algorithmic classification with manual classification for three specialties. Conclusions/Significance The resulting AACT database features study design attributes parsed into discrete fields, integrated metadata, and an integrated MeSH thesaurus, and is available for download as Oracle extracts (.dmp file and text format). This publicly-accessible dataset will facilitate analysis of studies and permit detailed characterization and analysis of the U.S. clinical trials enterprise as a whole. In addition, the methodology we present for creating specialty datasets may facilitate other efforts to analyze studies by specialty groups. PMID:22438982

The database for aggregate analysis of ClinicalTrials.gov (AACT) and subsequent regrouping by clinical specialty.

PubMed

Tasneem, Asba; Aberle, Laura; Ananth, Hari; Chakraborty, Swati; Chiswell, Karen; McCourt, Brian J; Pietrobon, Ricardo

2012-01-01

The ClinicalTrials.gov registry provides information regarding characteristics of past, current, and planned clinical studies to patients, clinicians, and researchers; in addition, registry data are available for bulk download. However, issues related to data structure, nomenclature, and changes in data collection over time present challenges to the aggregate analysis and interpretation of these data in general and to the analysis of trials according to clinical specialty in particular. Improving usability of these data could enhance the utility of ClinicalTrials.gov as a research resource. The purpose of our project was twofold. First, we sought to extend the usability of ClinicalTrials.gov for research purposes by developing a database for aggregate analysis of ClinicalTrials.gov (AACT) that contains data from the 96,346 clinical trials registered as of September 27, 2010. Second, we developed and validated a methodology for annotating studies by clinical specialty, using a custom taxonomy employing Medical Subject Heading (MeSH) terms applied by an NLM algorithm, as well as MeSH terms and other disease condition terms provided by study sponsors. Clinical specialists reviewed and annotated MeSH and non-MeSH disease condition terms, and an algorithm was created to classify studies into clinical specialties based on both MeSH and non-MeSH annotations. False positives and false negatives were evaluated by comparing algorithmic classification with manual classification for three specialties. The resulting AACT database features study design attributes parsed into discrete fields, integrated metadata, and an integrated MeSH thesaurus, and is available for download as Oracle extracts (.dmp file and text format). This publicly-accessible dataset will facilitate analysis of studies and permit detailed characterization and analysis of the U.S. clinical trials enterprise as a whole. In addition, the methodology we present for creating specialty datasets may facilitate other efforts to analyze studies by specialty groups.

Parents' perceived obstacles to pediatric clinical trial participation: Findings from the clinical trials transformation initiative.

PubMed

Greenberg, Rachel G; Gamel, Breck; Bloom, Diane; Bradley, John; Jafri, Hasan S; Hinton, Denise; Nambiar, Sumathi; Wheeler, Chris; Tiernan, Rosemary; Smith, P Brian; Roberts, Jamie; Benjamin, Daniel K

2018-03-01

Enrollment of children into pediatric clinical trials remains challenging. More effective strategies to improve recruitment of children into trials are needed. This study used in-depth qualitative interviews with parents who were approached to enroll their children in a clinical trial in order to gain an understanding of the barriers to pediatric clinical trial participation. Twenty-four parents whose children had been offered the opportunity to participate in a clinical trial were interviewed: 19 whose children had participated in at least 1 clinical trial and 5 who had declined participation in any trial. Each study aspect, from the initial explanation of the study to the end of the study, can affect the willingness of parents to consent to the proposed study and future studies. Establishing trust, appropriate timing, a transparent discussion of risks and benefits oriented to the layperson, and providing motivation for children to participate were key factors that impacted parents' decisions. In order for clinical trial accrual to be successful, parents' priorities and considerations must be a central focus, beginning with initial trial design. The recommendations from the parents who participated in this study can be used to support budget allocations that ensure adequate training of study staff and improved staffing on nights and weekends. Studies of parent responses in outpatient settings and additional inpatient settings will provide valuable information on the consent process from the child's and parent's perspectives. Further studies are needed to explore whether implementation of such strategies will result in improved recruitment for pediatric clinical trials.

Factors affecting Korean nursing student empowerment in clinical practice.

PubMed

Ahn, Yang-Heui; Choi, Jihea

2015-12-01

Understanding the phenomenon of nursing student empowerment in clinical practice is important. Investigating the cognition of empowerment and identifying predictors are necessary to enhance nursing student empowerment in clinical practice. To identify empowerment predictors for Korean nursing students in clinical practice based on studies by Bradbury-Jones et al. and Spreitzer. A cross-sectional design was used for this study. This study was performed in three nursing colleges in Korea, all of which had similar baccalaureate nursing curricula. Three hundred seven junior or senior nursing students completed a survey designed to measure factors that were hypothesized to influence nursing student empowerment in clinical practice. Data were collected from November to December 2011. Study variables included self-esteem, clinical decision making, being valued as a learner, satisfaction regarding practice with a team member, perception on professor/instructor/clinical preceptor attitude, and total number of clinical practice fields. Data were analyzed using stepwise multiple regression analyses. All of the hypothesized study variables were significantly correlated to nursing student empowerment. Stepwise multiple regression analysis revealed that clinical decision making in nursing (t=7.59, p<0.001), being valued as a learner (t=6.24, p<0.001), self-esteem (t=3.62, p<0.001), and total number of clinical practice fields (t=2.06, p=0.040). The explanatory power of these predictors was 35% (F=40.71, p<0.001). Enhancing nursing student empowerment in clinical practice will be possible by using educational strategies to improve nursing student clinical decision making. Simultaneously, attitudes of nurse educators are also important to ensure that nursing students are treated as valued learners and to increase student self-esteem in clinical practice. Finally, diverse clinical practice field environments should be considered to enhance experience. Copyright © 2015 Elsevier Ltd. All rights reserved.

Clinical application of antidepressant pharmacogenetics: considerations for the design of future studies.

PubMed

Fabbri, Chiara; Serretti, Alessandro

2018-06-12

A frustrating inertia has affected the development of clinical applications of antidepressant pharmacogenetics and personalized treatments of depression are still lacking 20 years after the first findings. Candidate gene studies provided replicated findings for some polymorphisms, but each of them shows at best a small effect on antidepressant efficacy and the cumulative effect of different polymorphisms is unclear. Further, no candidate was immune by at least some negative studies. These considerations give rise to some concerns about the clinical benefits of currently available pharmacogenetic tests since they are based on the results of candidate gene studies. Clinical guidelines in fact suggest that only polymorphisms that alter cytochrome 2D6 or 2C19 enzymatic activity probably provide useful clinical indications, while variants in genes involved in antidepressant pharmacodynamics have no recommended clinical applications. The present review discusses possible strategies to facilitate the identification of genetic biomarkers with clinical usefulness in guiding antidepressant treatments. These include analysis methods for the study of the polygenic/omnigenic nature of antidepressant response, the prioritization of polymorphisms on the basis of functional considerations, the incorporation of clinical-demographic predictors in pharmacogenetic studies (e.g. mixed polygenic and clinical risk scores), the application of methodological improvements to the design of future studies in order to maximize the comparability of results and improve power. Copyright © 2018. Published by Elsevier B.V.

Competence of novice nurses: role of clinical work during studying

PubMed Central

Manoochehri, H; Imani, E; Atashzadeh-Shoorideh, F; Alavi-Majd, A

2015-01-01

Aim: Clinical competence is to carry out the tasks with excellent results in a different of adjustments. According to various studies, one of the factors influencing clinical competence is work experience. This experience affects the integrity of students' learning experience and their practical skills. Many nursing students practice clinical work during their full-time studying. The aim of this qualitative research was to clarify the role of clinical work during studying in novice nurses' clinical competence. Methods: This qualitative content analysis performed with the conventional approach. All teaching hospitals of Hormozgan University of Medical Sciences selected as the research environment. To collect data, deep and semi-structured interviews, presence in the scene and manuscripts used. To provide feedback for the next release and the capacity of the data, interviews were transcribed verbatim immediately. Results: 45 newly-graduated nurses and head nurses between 23 and 40 with 1 to 18 years of experience participated in the study. After coding all interviews, 1250 original codes were derived. The themes extracted included: task rearing, personality rearing, knowledge rearing, and profession rearing roles of clinical work during studying. Conclusion: Working during studying can affect performance, personality, knowledge, and professional perspectives of novice nurses. Given the differences that may exist in clinical competencies of novice nurses with and without clinical work experience, it is important to pay more attention to this issue and emphasize on their learning in this period. PMID:28316703

The transfer of theoretical knowledge to clinical practice by nursing students and the difficulties they experience: A qualitative study.

PubMed

Günay, Ulviye; Kılınç, Gülsen

2018-06-01

Nursing education contains both theoretical and practical training processes. Clinical training is the basis of nursing education. The quality of clinical training is closely related to the quality of the clinical learning environment. This study aimed to determine the transfer of theoretical knowledge into clinical practice by nursing students and the difficulties they experience during this process. A qualitative research design was used in the study. The study was conducted in 2015 with 30 nursing students in a university located in the east of Turkey, constituting three focus groups. The questions directed to the students during the focus group interviews were as follows: What do you think about your clinical training? How do you evaluate yourself in the process of putting your theoretical knowledge into clinical practice? What kind of difficulties are you experiencing in clinical practices? The data were interpreted using the method of content analysis. Most of the students reported that theoretical information they received was excessive, their ability to put most of this information into practice was weak, and they lacked courage to touch patients for fear of implementing procedures incorrectly. As a result of the analysis of the data, five main themes were determined: clinical training, guidance and communication, hospital environment and expectations. The results of this study showed that nursing students found their clinical knowledge and skills insufficient and usually failed to transfer their theoretical knowledge into clinical practices. The study observed that nursing students experienced various issues in clinical practices. In order to fix these issues and achieve an effective clinical training environment, collaboration should be achieved among nursing instructors, nurses, nursing school and hospital managements. Additionally, the number of nursing educators should be increased and training programs should be provided regarding effective clinical training methods. Copyright © 2018 Elsevier Ltd. All rights reserved.

What is different about medical students interested in non-clinical careers?

PubMed Central

2013-01-01

Background The proportion of medical school graduates who pursue careers other than full-time clinical practice has increased in some countries as the physician’s role has evolved and diversified with the changing landscape of clinical practice and the advancement of biomedicine. Still, past studies of medical students’ career choices have focused on clinical specialties and little is known about their choice of non-clinical careers. The present study examined backgrounds, motivation and perceptions of medical students who intended non-clinical careers. Methods A questionnaire was administered to students at six Korean medical schools distributed across all provinces in the nation. The questionnaire comprised 40 items on respondents’ backgrounds, their motivation for and interest in the study of medicine, their perceptions of medical professions, and their career intentions. Data was analyzed using various descriptive and inferential statistics. Results In total, 1,388 students returned the questionnaire (60% response rate), 12.3% of whom intended non-clinical careers (i.e., basic sciences, non-clinical medical fields, and non-medical fields). Those who planned non-clinical careers were comparable with their peers in their motivation for studying medicine and in their views of medical professions, but they were less interested in the study of medicine (P < 0.01). The two groups also differed significantly on their perceptions of what was uninteresting about the study of medicine (P < 0.01). The two groups were comparable in gender and entry-level ratios but their distributions across ages and years of study differed significantly (P < 0.01). A majority of respondents agreed with the statements that “it is necessary for medical school graduates to pursue non-clinical careers” and that “medical schools need to offer programs that provide information on such careers.” Still, our finding indicates that medical school curricula do not address such needs sufficiently. Conclusions Our study found some differences in backgrounds and perceptions of the study of medicine in medical students interested in non-clinical careers from their peers. Future studies are suggested to enhance our understanding of medical students” choice of non-clinical careers. PMID:23731551

The Measurement of Causes of Patient Satisfaction and Dissatisfaction within Clinics at an Army Medical Treatment Facility

DTIC Science & Technology

1984-05-01

Satisfaction Measures Between Clinics.... 39 Lessons Learned From the Pilot Studies ...................... 42 Telephonic Versus Clinic Survey...Between Clinics. 63 Comments from Survey Participants ....................... 64 Lessons Learned from the Study ............................. 67...attempted to apply principles learned from a review of the multitude of studies conducted in the area of patient satisfaction. Validated dimensions of

Educating Parents About Pediatric Research: Children and Clinical Studies Website Qualitative Evaluation.

PubMed

Marceau, Lisa D; Welch, Lisa C; Pemberton, Victoria L; Pearson, Gail D

2016-07-01

A gap in information about pediatric clinical trials exists, and parents remain uncertain about what is involved in research studies involving children. We aimed to understand parent perspectives about pediatric clinical research after viewing the online Children and Clinical Studies (CaCS) program. Using a qualitative descriptive study design, we conducted focus groups with parents and phone interviews with physicians. Three themes emerged providing approaches to improve parent's understanding of clinical research by including strategies where parents (a) hear from parents like themselves to learn about pediatric research, (b) receive general clinical research information to complement study-specific details, and (c) are provided more information about the role of healthy child volunteers. Parents found the website a valuable tool that would help them make a decision about what it means to participate in research. This tool can assist parents, providers, and researchers by connecting general information with study-specific information. © The Author(s) 2015.

Non-clinical studies required for new drug development - Part I: early in silico and in vitro studies, new target discovery and validation, proof of principles and robustness of animal studies.

PubMed

Andrade, E L; Bento, A F; Cavalli, J; Oliveira, S K; Freitas, C S; Marcon, R; Schwanke, R C; Siqueira, J M; Calixto, J B

2016-10-24

This review presents a historical overview of drug discovery and the non-clinical stages of the drug development process, from initial target identification and validation, through in silico assays and high throughput screening (HTS), identification of leader molecules and their optimization, the selection of a candidate substance for clinical development, and the use of animal models during the early studies of proof-of-concept (or principle). This report also discusses the relevance of validated and predictive animal models selection, as well as the correct use of animal tests concerning the experimental design, execution and interpretation, which affect the reproducibility, quality and reliability of non-clinical studies necessary to translate to and support clinical studies. Collectively, improving these aspects will certainly contribute to the robustness of both scientific publications and the translation of new substances to clinical development.

The prevalence and clinical significance of maxillary sinus mucous retention cysts in a general clinic population.

PubMed

Rhodus, N L

1990-02-01

Previous studies have documented the occurrence and potential clinical significance of MSMR cysts. Studies also have alluded to a relationship between the MSMR cyst and certain signs or symptoms of disease. We determined the prevalence of MSMR cysts in a general clinic population and identified some important correlations with clinical signs and symptoms.

[Post-marketing reevaluation for potential quality risk and quality control in clinical application of traditional Chinese medicines].

PubMed

Li, Hong-jiao; He, Li-yun; Liu, Bao-yan

2015-06-01

The effective quality control in clinical practices is an effective guarantee for the authenticity and scientificity of the findings. The post-marketing reevaluation for traditional Chinese medicines (TCM) focuses on the efficacy, adverse reaction, combined medication and effective dose of drugs in the market by expanded clinical trials, and requires a larger sample size and a wider range of patients. Therefore, this increases the difficulty of quality control in clinical practices. With the experience in quality control in clinical practices for the post-marketing reevaluation for Kangbingdu oral for cold, researchers in this study reviewed the study purpose, project, scheme design and clinical practice process from an overall point of view, analyzed the study characteristics of the post-marketing reevaluation for TCMs and the quality control risks, designed the quality control contents with quality impacting factors, defined key review contents and summarized the precautions in clinical practices, with the aim to improve the efficiency of quality control of clinical practices. This study can provide reference to clinical units and quality control-related personnel in the post-marketing reevaluation for TCMs.

[Evidence-based quality assessment of 10-year orthodontic clinical trials in 4 major dental journals].

PubMed

Sun, Yan-nan; Lei, Fei-fei; Cao, Yan-li; Fu, Min-kui

2010-02-01

To assess the quality of orthodontic clinical trials published in 4 major dental journals in the past 10 years and establish the reference standard for orthodontic clinical trials and quality control of dental journals. All the clinical trials published in Chinese Journal of Stomatology, West China Journal of Stomatology, Journal of Practice Stomatology and Chinese Journal of Orthodontics from 1999 to 2008 were searched. The demographic information of the papers was extracted and the quality of the clinical trials according to the consolidated standards of reporting trials (CONSORT) was assessed. Four hundred and ninety-four clinical trials were retrieved, and 21.3% (105/494) of them were supported by grants. For the study design, only 26.1% (129/494) were prospective studies, and 3.8% (19/494) were randomized clinical trials. It was hard to evaluate precisely due to the lack of information about the details of the study designs. For the randomized clinical trials, the lack of details for randomization, allocation concealment, blinding and intention to treat compromised the quality. The general quality of clinical trials in orthodontics is poor. It needs to be improved both in the clinical study design and the paper writing.

An exploration into study design for biomarker identification: issues and recommendations.

PubMed

Hall, Jacqueline A; Brown, Robert; Paul, Jim

2007-01-01

Genomic profiling produces large amounts of data and a challenge remains in identifying relevant biological processes associated with clinical outcome. Many candidate biomarkers have been identified but few have been successfully validated and make an impact clinically. This review focuses on some of the study design issues encountered in data mining for biomarker identification with illustrations of how study design may influence the final results. This includes issues of clinical endpoint use and selection, power, statistical, biological and clinical significance. We give particular attention to study design for the application of supervised clustering methods for identification of gene networks associated with clinical outcome and provide recommendations for future work to increase the success of identification of clinically relevant biomarkers.

The development and psychometric testing of a theory-based instrument to evaluate nurses' perception of clinical reasoning competence.

PubMed

Liou, Shwu-Ru; Liu, Hsiu-Chen; Tsai, Hsiu-Min; Tsai, Ying-Huang; Lin, Yu-Ching; Chang, Chia-Hao; Cheng, Ching-Yu

2016-03-01

The purpose of the study was to develop and psychometrically test the Nurses Clinical Reasoning Scale. Clinical reasoning is an essential skill for providing safe and quality patient care. Identifying pre-graduates' and nurses' needs and designing training courses to improve their clinical reasoning competence becomes a critical task. However, there is no instrument focusing on clinical reasoning in the nursing profession. Cross-sectional design was used. This study included the development of the scale, a pilot study that preliminary tested the readability and reliability of the developed scale and a main study that implemented and tested the psychometric properties of the developed scale. The Nurses Clinical Reasoning Scale was developed based on the Clinical Reasoning Model. The scale includes 15 items using a Likert five-point scale. Data were collected from 2013-2014. Two hundred and fifty-one participants comprising clinical nurses and nursing pre-graduates completed and returned the questionnaires in the main study. The instrument was tested for internal consistency and test-retest reliability. Its validity was tested with content, construct and known-groups validity. One factor emerged from the factor analysis. The known-groups validity was confirmed. The Cronbach's alpha for the entire instrument was 0·9. The reliability and validity of the Nurses Clinical Reasoning Scale were supported. The scale is a useful tool and can be easily administered for the self-assessment of clinical reasoning competence of clinical nurses and future baccalaureate nursing graduates. Study limitations and further recommendations are discussed. © 2015 John Wiley & Sons Ltd.

Professional Development through Clinical Supervision

ERIC Educational Resources Information Center

Farhat, Amal

2016-01-01

Studies have shown that clinical supervisory practices result in implementation of new skills in teachers' classroom performance. This study examines the impact of two clinical supervisory cycles on teachers' performance in classroom management. Multiple data collection tools were used to determine the impact of clinical supervisory interventions…

Towards Data Value-Level Metadata for Clinical Studies.

PubMed

Zozus, Meredith Nahm; Bonner, Joseph

2017-01-01

While several standards for metadata describing clinical studies exist, comprehensive metadata to support traceability of data from clinical studies has not been articulated. We examine uses of metadata in clinical studies. We examine and enumerate seven sources of data value-level metadata in clinical studies inclusive of research designs across the spectrum of the National Institutes of Health definition of clinical research. The sources of metadata inform categorization in terms of metadata describing the origin of a data value, the definition of a data value, and operations to which the data value was subjected. The latter is further categorized into information about changes to a data value, movement of a data value, retrieval of a data value, and data quality checks, constraints or assessments to which the data value was subjected. The implications of tracking and managing data value-level metadata are explored.

Using EHR audit trail logs to analyze clinical workflow: A case study from community-based ambulatory clinics.

PubMed

Wu, Danny T Y; Smart, Nikolas; Ciemins, Elizabeth L; Lanham, Holly J; Lindberg, Curt; Zheng, Kai

2017-01-01

To develop a workflow-supported clinical documentation system, it is a critical first step to understand clinical workflow. While Time and Motion studies has been regarded as the gold standard of workflow analysis, this method can be resource consuming and its data may be biased due to the cognitive limitation of human observers. In this study, we aimed to evaluate the feasibility and validity of using EHR audit trail logs to analyze clinical workflow. Specifically, we compared three known workflow changes from our previous study with the corresponding EHR audit trail logs of the study participants. The results showed that EHR audit trail logs can be a valid source for clinical workflow analysis, and can provide an objective view of clinicians' behaviors, multi-dimensional comparisons, and a highly extensible analysis framework.

Effectiveness of a mobile cooperation intervention during the clinical practicum of nursing students: a parallel group randomized controlled trial protocol.

PubMed

Strandell-Laine, Camilla; Saarikoski, Mikko; Löyttyniemi, Eliisa; Salminen, Leena; Suomi, Reima; Leino-Kilpi, Helena

2017-06-01

The aim of this study was to describe a study protocol for a study evaluating the effectiveness of a mobile cooperation intervention to improve students' competence level, self-efficacy in clinical performance and satisfaction with the clinical learning environment. Nursing student-nurse teacher cooperation during the clinical practicum has a vital role in promoting the learning of students. Despite an increasing interest in using mobile technologies to improve the clinical practicum of students, there is limited robust evidence regarding their effectiveness. A multicentre, parallel group, randomized, controlled, pragmatic, superiority trial. Second-year pre-registration nursing students who are beginning a clinical practicum will be recruited from one university of applied sciences. Eligible students will be randomly allocated to either a control group (engaging in standard cooperation) or an intervention group (engaging in mobile cooperation) for the 5-week the clinical practicum. The complex mobile cooperation intervention comprises of a mobile application-assisted, nursing student-nurse teacher cooperation and a training in the functions of the mobile application. The primary outcome is competence. The secondary outcomes include self-efficacy in clinical performance and satisfaction with the clinical learning environment. Moreover, a process evaluation will be undertaken. The ethical approval for this study was obtained in December 2014 and the study received funding in 2015. The results of this study will provide robust evidence on mobile cooperation during the clinical practicum, a research topic that has not been consistently studied to date. © 2016 John Wiley & Sons Ltd.

Validation of the Clinical Learning Environment Inventory.

PubMed

Chan, Dominic S

2003-08-01

One hundred eight preregistration nursing students took part in this survey study, which assessed their perceptions of the clinical learning environment. Statistical data based on the sample confirmed the reliability and validity of the Clinical Learning Environment Inventory (CLEI), which was developed using the concept of classroom learning environment studies. The study also found that there were significant differences between students' actual and preferred perceptions of the clinical learning environments. In terms of the CLEI scales, students preferred a more positive and favorable clinical environment than they perceived as being actually present. The achievement of certain outcomes of clinical field placements might be enhanced by attempting to change the actual clinical environment in ways that make it more congruent with that preferred by the students.

ClinicalTrials.gov, stem cells and 'pay-to-participate' clinical studies.

PubMed

Turner, Leigh

2017-09-01

Numerous US businesses that engage in direct-to-consumer advertising of stem cell interventions that are not US FDA-approved also recruit clients by listing 'pay-to-participate' studies listed on ClinicalTrials.gov . Individuals considering enrolling in such studies and NIH officials responsible for overseeing the database need to be aware that some businesses are using the registry to promote unapproved stem cell interventions that study subjects are charged to receive. Inclusion of such studies in ClinicalTrials.gov reveals that the database needs better screening tools. In particular, screening should evaluate whether studies submitted to the registry have been reviewed and permitted to proceed by the FDA in the case of clinical studies requiring FDA clearance in addition to institutional review board approval.

Poststroke Seizures and Epilepsy: Clinical Studies and Animal Models

PubMed Central

Kelly, Kevin M.

2002-01-01

Poststroke seizures and epilepsy have been described in numerous clinical studies for many years. Most studies are retrospective in design, include relatively small numbers of patients, have limited periods of follow-up, and report a diversity of findings. Well-designed clinical trials and population studies in the recent past addressed several critical clinical issues and generated important findings regarding the occurrence of poststroke seizures and epilepsy. In contrast, the pathophysiologic events of injured brain that establish poststroke epileptogenesis are not well understood, and animal modeling has had limited development. Reviews of several important clinical studies and animal models that hold promise for a better understanding of poststroke epileptogenesis are presented. PMID:15309107

[Clinical relevance of periodic limb movements during sleep in obstructive sleep apnea patients].

PubMed

Iriarte, J; Alegre, M; Irimia, P; Urriza, J; Artieda, J

The periodic limb movements disorder (PLMD) is frequently associated with the obstructive sleep apnea syndrome (OSAS), but the prevalence and clinical relevance of this association have not been studied in detail. The objectives were to make a prospective study on the prevalence of PLMD in patients with OSAS, and correlate this association with clinical and respiratory parameters. Forty-two patients diagnosed with OSAS, without clinical suspicion of PLMD, underwent a polysomnographic study. Clinical symptoms and signs were evaluated with an structured questionnaire, and respiratory parameters were obtained from the nocturnal study. Periodic limb movements were found in 10 patients (24%). There were no differences in clinical parameters between both groups (with and without periodical limb movements). However, respiratory parameters were significantly worse in patients without PLMD. PLMD is very frequent in patients with OSAS, and can contribute to worsen clinical signs and symptoms in these patients independently from respiratory parameters.

Self-Reflection of Video-Recorded High-Fidelity Simulations and Development of Clinical Judgment.

PubMed

Bussard, Michelle E

2016-09-01

Nurse educators are increasingly using high-fidelity simulators to improve prelicensure nursing students' ability to develop clinical judgment. Traditionally, oral debriefing sessions have immediately followed the simulation scenarios as a method for students to connect theory to practice and therefore develop clinical judgment. Recently, video recording of the simulation scenarios is being incorporated. This qualitative, interpretive description study was conducted to identify whether self-reflection on video-recorded high-fidelity simulation (HFS) scenarios helped prelicensure nursing students to develop clinical judgment. Tanner's clinical judgment model was the framework for this study. Four themes emerged from this study: Confidence, Communication, Decision Making, and Change in Clinical Practice. This study indicated that self-reflection of video-recorded HFS scenarios is beneficial for prelicensure nursing students to develop clinical judgment. [J Nurs Educ. 2016;55(9):522-527.]. Copyright 2016, SLACK Incorporated.

Characteriation of clinical data packages using foreign data in new drug applications in Japan.

PubMed

Tanaka, M; Nagata, T

2008-09-01

The objective of this research was to characterize clinical data packages (CDPs) of new drug applications (NDAs) using foreign data based on the International Conference on Harmonization (ICH) E5 guideline. Official review reports of NDAs approved in Japan between January 1999 and April 2005 were examined. Those NDAs considered by the official reviewers to be approved based on the ICH E5 guideline (E5-NDAs) were identified and classified into six categories of approval requirements in Japan. The details of pivotal clinical efficacy studies in the CDPs were examined. Forty-one NDAs were identified as E5-NDAs. Pivotal clinical studies conducted in Japan were required by the E5-NDAs, except for nine of those in which the foreign clinical studies reduced Japanese clinical studies in the CDPs. Given the differences in approval requirements among regions, the acceptability of foreign clinical data to Japanese approval is limited.

Health effects of intermittent fasting: hormesis or harm? A systematic review.

PubMed

Horne, Benjamin D; Muhlestein, Joseph B; Anderson, Jeffrey L

2015-08-01

Intermittent fasting, alternate-day fasting, and other forms of periodic caloric desistance are gaining popularity in the lay press and among animal research scientists. Whether clinical evidence exists for or is strong enough to support the use of such dietary regimens as health interventions is unclear. This review sought to identify rigorous, clinically relevant research studies that provide high-quality evidence that therapeutic fasting regimens are clinically beneficial to humans. A systematic review of the published literature through January 2015 was performed by using sensitive search strategies to identify randomized controlled clinical trials that evaluated the effects of fasting on either clinically relevant surrogate outcomes (e.g., weight, cholesterol) or actual clinical event endpoints [e.g., diabetes, coronary artery disease (CAD)] and any other studies that evaluated the effects of fasting on clinical event outcomes. Three randomized controlled clinical trials of fasting in humans were identified, and the results were published in 5 articles, all of which evaluated the effects of fasting on surrogate outcomes. Improvements in weight and other risk-related outcomes were found in the 3 trials. Two observational clinical outcomes studies in humans were found in which fasting was associated with a lower prevalence of CAD or diabetes diagnosis. No randomized controlled trials of fasting for clinical outcomes were identified. Clinical research studies of fasting with robust designs and high levels of clinical evidence are sparse in the literature. Whereas the few randomized controlled trials and observational clinical outcomes studies support the existence of a health benefit from fasting, substantial further research in humans is needed before the use of fasting as a health intervention can be recommended. © 2015 American Society for Nutrition.

Standardization of Clinical Assessment and Sample Collection Across All PERCH Study Sites

PubMed Central

Prosperi, Christine; Baggett, Henry C.; Brooks, W. Abdullah; Deloria Knoll, Maria; Hammitt, Laura L.; Howie, Stephen R. C.; Kotloff, Karen L.; Levine, Orin S.; Madhi, Shabir A.; Murdoch, David R.; O’Brien, Katherine L.; Thea, Donald M.; Awori, Juliet O.; Bunthi, Charatdao; DeLuca, Andrea N.; Driscoll, Amanda J.; Ebruke, Bernard E.; Goswami, Doli; Hidgon, Melissa M.; Karron, Ruth A.; Kazungu, Sidi; Kourouma, Nana; Mackenzie, Grant; Moore, David P.; Mudau, Azwifari; Mwale, Magdalene; Nahar, Kamrun; Park, Daniel E.; Piralam, Barameht; Seidenberg, Phil; Sylla, Mamadou; Feikin, Daniel R.; Scott, J. Anthony G.; O’Brien, Katherine L.; Levine, Orin S.; Knoll, Maria Deloria; Feikin, Daniel R.; DeLuca, Andrea N.; Driscoll, Amanda J.; Fancourt, Nicholas; Fu, Wei; Hammitt, Laura L.; Higdon, Melissa M.; Kagucia, E. Wangeci; Karron, Ruth A.; Li, Mengying; Park, Daniel E.; Prosperi, Christine; Wu, Zhenke; Zeger, Scott L.; Watson, Nora L.; Crawley, Jane; Murdoch, David R.; Brooks, W. Abdullah; Endtz, Hubert P.; Zaman, Khalequ; Goswami, Doli; Hossain, Lokman; Jahan, Yasmin; Ashraf, Hasan; Howie, Stephen R. C.; Ebruke, Bernard E.; Antonio, Martin; McLellan, Jessica; Machuka, Eunice; Shamsul, Arifin; Zaman, Syed M.A.; Mackenzie, Grant; Scott, J. Anthony G.; Awori, Juliet O.; Morpeth, Susan C.; Kamau, Alice; Kazungu, Sidi; Kotloff, Karen L.; Tapia, Milagritos D.; Sow, Samba O.; Sylla, Mamadou; Tamboura, Boubou; Onwuchekwa, Uma; Kourouma, Nana; Toure, Aliou; Madhi, Shabir A.; Moore, David P.; Adrian, Peter V.; Baillie, Vicky L.; Kuwanda, Locadiah; Mudau, Azwifarwi; Groome, Michelle J.; Baggett, Henry C.; Thamthitiwat, Somsak; Maloney, Susan A.; Bunthi, Charatdao; Rhodes, Julia; Sawatwong, Pongpun; Akarasewi, Pasakorn; Thea, Donald M.; Mwananyanda, Lawrence; Chipeta, James; Seidenberg, Phil; Mwansa, James; wa Somwe, Somwe; Kwenda, Geoffrey

2017-01-01

Abstract Background. Variable adherence to standardized case definitions, clinical procedures, specimen collection techniques, and laboratory methods has complicated the interpretation of previous multicenter pneumonia etiology studies. To circumvent these problems, a program of clinical standardization was embedded in the Pneumonia Etiology Research for Child Health (PERCH) study. Methods. Between March 2011 and August 2013, standardized training on the PERCH case definition, clinical procedures, and collection of laboratory specimens was delivered to 331 clinical staff at 9 study sites in 7 countries (The Gambia, Kenya, Mali, South Africa, Zambia, Thailand, and Bangladesh), through 32 on-site courses and a training website. Staff competency was assessed throughout 24 months of enrollment with multiple-choice question (MCQ) examinations, a video quiz, and checklist evaluations of practical skills. Results. MCQ evaluation was confined to 158 clinical staff members who enrolled PERCH cases and controls, with scores obtained for >86% of eligible staff at each time-point. Median scores after baseline training were ≥80%, and improved by 10 percentage points with refresher training, with no significant intersite differences. Percentage agreement with the clinical trainer on the presence or absence of clinical signs on video clips was high (≥89%), with interobserver concordance being substantial to high (AC1 statistic, 0.62–0.82) for 5 of 6 signs assessed. Staff attained median scores of >90% in checklist evaluations of practical skills. Conclusions. Satisfactory clinical standardization was achieved within and across all PERCH sites, providing reassurance that any etiological or clinical differences observed across the study sites are true differences, and not attributable to differences in application of the clinical case definition, interpretation of clinical signs, or in techniques used for clinical measurements or specimen collection. PMID:28575355

The Future of Clinical Education: Using the Delphi Technique to Study Allied Health Deans' Perspectives on Definitions and Goals.

PubMed

Romig, Barbara D; Tucker, Ann W; Hewitt, Anne M; O'Sullivan Maillet, Julie

2016-01-01

Allied health (AH) clinical education provides future health professionals with the experiences necessary to develop the healthcare competencies required for success in their individual fields. There is limited information and consensus on the purposes of clinical education, including its definition and goals, and its comprehensive role in AH clinical training. This study explored whether consensus could be achieved in the definition, goals, and factors impacting AH clinical education. An expert panel consisting of 61 AH deans (54.9% of the population) whose institutions were 2013 members of the Association of Schools of Allied Health Professions (ASAHP) participated in a three-round Delphi study. From July 2013 to March 2014, the deans expressed opinions about clinical education and its purposes. Responses were collected, summarized, and refined, and responses were accepted and re-rated until agreement was achieved or the study concluded. The hypothesis that AH deans would agree upon the definition and goals of clinical education was supported by this study's findings. Over 90% of deans "strongly agreed" or "agreed" on the definition of clinical education. A majority (90.2% to 92.7%) agreed with the goals. High agreement was achieved on the purposes of clinical education, resulting in a comprehensive definition of and goals for AH clinical education. The definition and goals of clinical education can be added in the healthcare literature and used in support of AH education.

A multicenter study: how do medical students perceive clinical learning climate?

PubMed Central

Yilmaz, Nilufer Demiral; Velipasaoglu, Serpil; Ozan, Sema; Basusta, Bilge Uzun; Midik, Ozlem; Mamakli, Sumer; Karaoglu, Nazan; Tengiz, Funda; Durak, Halil İbrahim; Sahin, Hatice

2016-01-01

Background The relationship between students and instructors is of crucial importance for the development of a positive learning climate. Learning climate is a multifaceted concept, and its measurement is a complicated process. The aim of this cross-sectional study was to determine medical students’ perceptions about the clinical learning climate and to investigate differences in their perceptions in terms of various variables. Methods Medical students studying at six medical schools in Turkey were recruited for the study. All students who completed clinical rotations, which lasted for 3 or more weeks, were included in the study (n=3,097). Data were collected using the Clinical Learning Climate Scale (CLCS). The CLCS (36 items) includes three subscales: clinical environment, emotion, and motivation. Each item is scored using a 5-point Likert scale (1: strongly disagree to 5: strongly agree). Results The response rate for the trainees was 69.67% (n=1,519), and for the interns it was 51.47% (n=917). The mean total CLCS score was 117.20±17.19. The rotation during which the clinical learning climate was perceived most favorably was the Physical Therapy and Rehabilitation rotation (mean score: 137.77). The most negatively perceived rotation was the General Internal Medicine rotation (mean score: 104.31). There were significant differences between mean total scores in terms of trainee/intern characteristics, internal medicine/surgical medicine rotations, and perception of success. Conclusion The results of this study drew attention to certain aspects of the clinical learning climate in medical schools. Clinical teacher/instructor/supervisor, clinical training programs, students’ interactions in clinical settings, self-realization, mood, students’ intrinsic motivation, and institutional commitment are important components of the clinical learning climate. For this reason, the aforementioned components should be taken into consideration in studies aiming to improve clinical learning climate. PMID:27640648

Prevalence of common mental disorders among Dutch medical students and related use and need of mental health care: a cross-sectional study.

PubMed

Gaspersz, Roxanne; Frings-Dresen, Monique H W; Sluiter, Judith K

2012-02-15

The purpose of the study was to assess common mental disorders and the related use and need for mental health care among clinically not yet active and clinically active medical students. All medical students (n=2266) at one Dutch medical university were approached. Students from study years 1-4 were defined as clinically not yet active and students from study years 5 and 6 as clinically active. An electronic survey was used to detect common mental disorders depression (BSI-DEP), anxiety (BSI-ANG), stress (4DSQ) and post-traumatic stress disorder (IES). The use of mental health services in the past 3 months and the need for mental health services were asked for. The prevalence of common mental disorders, the use and need for mental health services and differences between groups were calculated. The response rate was 52%: 814 clinically not yet active and 316 clinically active students. The prevalence of common mental disorders among clinically not yet active and clinically active students was 54% and 48%, respectively. The use of mental health services was 14% in clinically not yet active and 12% in clinically active students with common mental disorders (n.s.). The need for mental health services by clinically not yet active and clinically active students was 52% and 46%, respectively (n.s.). The prevalence of probable common mental disorders are higher among clinically not yet active than among clinically active students. The need of mental health services exceeds use, but is the same in the two groups of students.

Analyzing the effectiveness of teaching and factors in clinical decision-making.

PubMed

Hsieh, Ming-Chen; Lee, Ming-Shinn; Chen, Tsung-Ying; Tsai, Tsuen-Chiuan; Pai, Yi-Fong; Sheu, Min-Muh

2017-01-01

The aim of this study is to prepare junior physicians, clinical education should focus on the teaching of clinical decision-making. This research is designed to explore teaching of clinical decision-making and to analyze the benefits of an "Analogy guide clinical decision-making" as a learning intervention for junior doctors. This study had a "quasi-experimental design" and was conducted in a medical center in eastern Taiwan. Participants and Program Description: Thirty junior doctors and three clinical teachers were involved in the study. The experimental group (15) received 1 h of instruction from the "Analogy guide for teaching clinical decision-making" every day for 3 months. Program Evaluation: A "Clinical decision-making self-evaluation form" was used as the assessment tool to evaluate participant learning efficiency before and after the teaching program. Semi-structured qualitative research interviews were also conducted. We found using the analogy guide for teaching clinical decision-making could help enhance junior doctors' self-confidence. Important factors influencing clinical decision-making included workload, decision-making, and past experience. Clinical teaching using the analogy guide for clinical decision-making may be a helpful tool for training and can contribute to a more comprehensive understanding of decision-making.

Culturally and linguistically diverse healthcare students' experiences of learning in a clinical environment: A systematic review of qualitative studies.

PubMed

Mikkonen, Kristina; Elo, Satu; Kuivila, Heli-Maria; Tuomikoski, Anna-Maria; Kääriäinen, Maria

2016-02-01

Learning in the clinical environment of healthcare students plays a significant part in higher education. The greatest challenges for culturally and linguistically diverse healthcare students were found in clinical placements, where differences in language and culture have been shown to cause learning obstacles for students. There has been no systematic review conducted to examine culturally and linguistically diverse healthcare students' experiences of their learning in the clinical environment. This systematic review aims to identify culturally and linguistically diverse healthcare students' experiences of learning in a clinical environment. The search strategy followed the guidelines of the Centre of Reviews and Dissemination. The original studies were identified from seven databases (CINAHL, Medline Ovid, Scopus, Web of Science, Academic Search Premiere, Eric and Cochrane Library) for the period 2000-2014. Two researchers selected studies based on titles, abstracts and full texts using inclusion criteria and assessed the quality of studies independently. Twelve original studies were chosen for the review. The culturally and linguistically diverse healthcare students' learning experiences were divided into three influential aspects of learning in a clinical environment: experiences with implementation processes and provision; experiences with peers and mentors; and experiences with university support and instructions. The main findings indicate that culturally and linguistically diverse healthcare students embarking on clinical placements initially find integration stressful. Implementing the process of learning in a clinical environment requires additional time, well prepared pedagogical orientation, prior cultural and language education, and support for students and clinical staff. Barriers to learning by culturally and linguistically diverse healthcare students were not being recognized and individuals were not considered motivated; learners experienced the strain of being different, and faced language difficulties. Clinical staff attitudes influenced students' clinical learning experiences and outcomes. Additional education in culture and language for students and clinical staff is considered essential to improve the clinical learning experiences of culturally and linguistically diverse healthcare students. Further studies of culturally and linguistically diverse healthcare students' learning experiences in the clinical environment need to be conducted in order to examine influential aspects on the clinical learning found in the review. Copyright © 2015 Elsevier Ltd. All rights reserved.