The use of a physiologically based pharmacokinetic model to evaluate deconvolution measurements of systemic absorption

Background

An unknown input function can be determined by deconvolution using the systemic bolus input function (r) determined using an experimental input of duration ranging from a few seconds to many minutes. The quantitative relation between the duration of the input and the accuracy of r is unknown. Although a large number of deconvolution procedures have been described, these routines are not available in a convenient software package.

Methods

Four deconvolution methods are implemented in a new, user-friendly software program (PKQuest, http://www.pkquest.com). Three of these methods are characterized by input parameters that are adjusted by the user to provide the "best" fit. A new approach is used to determine these parameters, based on the assumption that the input can be approximated by a gamma distribution. Deconvolution methodologies are evaluated using data generated from a physiologically based pharmacokinetic model (PBPK).

Results and Conclusions

The 11-compartment PBPK model is accurately described by either a 2 or 3-exponential function, depending on whether or not there is significant tissue binding. For an accurate estimate of r the first venous sample should be at or before the end of the constant infusion and a long (10 minute) constant infusion is preferable to a bolus injection. For noisy data, a gamma distribution deconvolution provides the best result if the input has the form of a gamma distribution. For other input functions, good results are obtained using deconvolution methods based on modeling the input with either a B-spline or uniform dense set of time points.

     

Evaluation of a large healthy lifestyle program: informing program implementation and scale-up in the prevention of obesity

Background

The Healthy Lifestyle Program for women (HeLP-her) is a low-intensity, self-management program which has demonstrated efficacy in preventing excess weight gain in women. However, little is known about the implementation, reach, and sustainability of low-intensity prevention programs in rural settings, where risk for obesity in women is higher than urban settings. We aimed to evaluate a low-intensity healthy lifestyle program delivered to women in a rural setting to inform development of effective community prevention programs.

Methods

A mixed method hybrid implementation and evaluation study, guided by the RE-AIM framework (addressing the Reach, Effectiveness, Adoption, Implementation, and Maintenance), was undertaken. Data collection tools included anthropometric measures, program checklists, questionnaires, and semi-structured interviews with participants and local stakeholders. The RE-AIM self-audit tool was applied to assess evaluation rigor.

Results

Six hundred and forty-nine women from 41 relatively socio-economic disadvantaged communities in Australia participated: mean age 39.6 years (±SD 6.7) and body mass index of 28.8 kg/m² (±SD 6.9). A between-group weight difference of ?0.92 kg (95% CI ?1.67 to ?0.16) showed program effectiveness. Reach was broad across 41 towns with 62% of participants reporting influencing some of the health behaviors of their families. Strong implementation fidelity was achieved with good retention rates at 1 year (76%) and high participant satisfaction (82% of participants willing to recommend this program). Over 300 multi-level community partnerships were established supporting high adoption. Stakeholders reported potential capacity to implement and sustain the prevention program in resource poor rural settings, due to the low-intensity design and minimal resources required.

Conclusions

Our comprehensive RE-AIM evaluation demonstrates that an evidence-based obesity prevention program can be successfully implemented in real-world settings. The program achieved broad reach, effectiveness, and satisfaction at the community and stakeholder level, revealing potential for program sustainability. The evaluation addressed implementation knowledge gaps to support future obesity prevention program scale-up.

Trial registration

Australian and New Zealand Clinical Trial Registry ACTRN 12612000115831 [http://www.anzctr.org.au/].

     

TEACCH-based group social skills training for children with high-functioning autism: a pilot randomized controlled trial

Background

Although social skills training programs for people with high-functioning autism (HFA) are widely practiced, the standardization of curricula, the examination of clinical effectiveness, and the evaluation of the feasibility of future trials have yet to be done in Asian countries. To compensate for this problem, a Japanese pilot randomized controlled trial (RCT) of the Treatment and Education of Autistic and Related Communication Handicapped Children (TEACCH)-based group social skills training for children with HFA and their mothers was conducted.

Methods

Eleven children with HFA, aged 5–6 years, and their mothers were randomly assigned to the TEACCH program (n=5) or a waiting-list control group (n=6). The program involved comprehensive group intervention and featured weekly 2-hour sessions, totaling 20 sessions over six months. The adaptive behaviors and social reciprocity of the children, parenting stress, and parent–child interactions were assessed using the Strengths and Difficulties Questionnaire (SDQ), Parenting Stress Index (PSI), Beck depression inventory-II (BDI-II), and Interaction Rating Scale (IRS).

Results

Through this pilot trial, the intervention and evaluation of the program has been shaped. There were no dropouts from the program and the mothers’ satisfaction was high. The outcome measurements improved more in the program group than in the control group, with moderate effect sizes (SDQ, 0.71; PSI, 0.58; BDI-II, 0.40; and IRS, 0.69). This pilot trial also implied that this program is more beneficial for high IQ children and mothers with low stress than for those who are not.

Conclusion

We have standardized the TEACCH program, confirmed the feasibility of a future trial, and successfully estimated the positive effect size. These findings will contribute to a larger trial in the future and to forthcoming systematic reviews with meta-analyses.

Trial registration

UMIN000004560

     

Factors influencing adherence to an app-based exercise program in adolescents with painful hyperkyphosis

Background

Software applications (apps) could potentially promote exercise adherence. However, it is unclear whether adolescents with painful hyperkyphosis will use an app designed for a home exercise program. The purpose of this study is to assess factors regarding adherence to an app-based home exercise program in adolescents with hyperkyphosis and back pain who were provided a one-time exercise treatment.

Methods

Twenty-one participants were instructed in a one-time exercise treatment and asked to complete a home exercise program 3 times a week for 6 months using an app called PT PAL. At a 6-month follow-up, 14 participants completed a survey assessing factors related to their experiences using the app and their treatment engagement.

Results

Although most participants did not use the app, they reported performing their exercises a few times per week. The adolescent participants considered the app to be more of a barrier than a supportive measure for promoting exercise adherence. Most participants still reported bothersome back pain.

Conclusions

Although adherence to the 6-month app-based home exercise program was not successful, adolescents still viewed technology support such as text reminders as a potential solution.

Trial registration

ClinicalTrials.gov Identifier: NCT03212664. Registered 11 July 2017. Retrospectively registered.

     

The effect of lifestyle intervention in obesity on the soluble form of activated leukocyte cell adhesion molecule

Background

The aim of this study was to investigate the effect of a lifestyle intervention in obesity on the soluble form of the activated leukocyte cell adhesion molecule (sALCAM) and its association with metabolic parameters.

Methods

Twenty-nine obese subjects selected from the OPTIFAST®52 program. This program consisted into 2 crucial phases: an initial 12-week active weight reduction phase, followed by a 40-week weight maintenance phase. At baseline, after 12 weeks and at the end of the program, fasting glucose and insulin, total cholesterol, LDL-C, HDL-C, triglycerides, adiponectin, leptin, high sensitivity CRP, sALCAM, homeostasis model assessment-estimated insulin resistance (HOMA-IR) and leptin-to-adiponectin-ratio were determined. Oral glucose tolerance test (OGTT) was performed when indicated.

Results

At baseline, the serum concentration of sALCAM was increased and correlated positively with HOMA-IR and negatively with age. At the end of the program, sALCAM concentrations decreased significantly. Multivariate analysis showed that sALCAM significantly correlated with age, glucose concentration after 2 h OGTT and the HOMA-IR. A higher decrease of HOMA-IR during the study was observed in subjects with higher concentration of sALCAM at baseline.

Conclusions

sALCAM might be a novel biomarker in obesity that correlates and predicts insulin sensitivity improvement and that can be affected by lifestyle intervention.

     

Brief internet-based cognitive behavior therapy program with a supplement drink improved anxiety and somatic symptoms in Japanese workers

Background

Self-help cognitive behavior therapy (CBT) is a useful approach for the treatment of psychological problems. Recent research on the effectiveness of self-help internet-based CBT (ICBT) indicates that the paradigm moderately improves psychological problems. Furthermore, previous studies have shown that food and drinks containing supplements improve various health conditions. We investigated the effect of a brief self-help ICBT administered with a supplement drink on psychological well-being and somatic symptoms.

Methods

In total, 101 healthy workers were enrolled in the 4-week ICBT program, which consisted of psychoeducation on stress management, behavior activation, and cognitive restructuring. The supplement soft drink was taken every day during the program. The participants were instructed to watch on-demand video clips and read the self-help guidebook and supporting comic strip weekly on the Internet or smartphone. The Japanese version of the Profile of Mood States (POMS) was administered before and after completion of the program. Scores on the POMS tension-anxiety (POMS-TA), depression (POMS-D), and fatigue (POMS-F) subscales were used to assess the effect of the program. Somatic symptoms were assessed using the Brief Job Stress Questionnaire.

Results

In total, 75 participants continued the program for 4 weeks; however, of those, 27 failed to complete all weekly tasks or meet the post-assessment deadlines. Therefore, the data of 48 participants were included in the analysis. Pre-post intervention comparisons using paired t-tests revealed significant improvement on the POMS-TA, but not the POMS-D or POMS-F subscales. Moreover, participants reported a significant reduction in the severity of low back pain.

Conclusion

Our brief intervention moderately improved anxiety levels and the symptom of low back pain. These findings suggest that the brief ICBT program is effective in non-patient populations. Future directions for brief ICBT are discussed.

Trial registration

This study was registered on February 10, 2016 at UMIN. The registration number is UMIN000020962.

     

Analysis of impulse oscillometric measures of lung function and respiratory system model parameters in small airway-impaired and healthy children over a 2-year period

Background

Is Impulse Oscillometry System (IOS) a valuable tool to measure respiratory system function in Children?Asthma (A) is the most prevalent chronic respiratory disease in children. Therefore, early and accurate assessment of respiratory function is of tremendous clinical interest in diagnosis, monitoring and treatment of respiratory conditions in this subpopulation.IOS has been successfully used to measure lung function in children with a high degree of sensitivity and specificity to small airway impairments (SAI) and asthma. IOS measures of airway function and equivalent electrical circuit models of the human respiratory system have been developed to quantify the severity of these conditions. Previously, we have evaluated several known respiratory models based on the Mead's model and more parsimonious versions based on fitting IOS data known as extended RIC (eRIC) and augmented RIC (aRIC) models have emerged, which offer advantages over earlier models.

Methods

IOS data from twenty-six children were collected and compared during pre-bronchodilation (pre-B) and post- bronchodilation (post-B) conditions over a period of 2 years.

Results and Discussion

Are the IOS and model parameters capable of differentiating between healthy children and children with respiratory system distress?Children were classified into two main categories: Healthy (H) and Small Airway-Impaired (SAI). The IOS measures and respiratory model parameters analyzed differed consistently between H and SAI children. SAI children showed smaller trend of "growth" and larger trend of bronchodilator responses than H children.The two model parameters: peripheral compliance (Cp) and peripheral resistance (Rp) tracked IOS indices of small airway function well. Cp was a more sensitive index than Rp. Both eRIC and aRIC Cps and the IOS Reactance Area, AX, (also known as the "Goldman Triangle") showed good correlations.

Conclusions

What are the most useful IOS and model parameters?In this work we demonstrate that IOS parameters such as resistance at 5 Hz (R5), frequency-dependence of resistance (fdR: R5-R20), reactance area (AX), and parameter estimates of respiratory system such as Cp and Rp provide sensitive indicators of lung function and have the capacity to differentiate between obstructed and non-obstructed airway conditions. They are also capable of demonstrating airway growth-related changes over a two-year period.We conclude that the IOS parameters AX and the eRIC model derived parameter Cp are the most reliable parameters to track lung function in children before and after bronchodilator and over a time period (2 years).Which model is more suitable for interpreting IOS data?IOS data are equally well-modelled by eRIC and aRIC models, based on the close correlations of their corresponding parameters - excluding upper airway shunt compliance. The eRIC model is a more parsimonious and equally powerful model in capturing the differences in IOS indices between SAI and H children. Therefore, it may be considered a clinically-preferred model of lung function.

     

Dynamic Optimization with Particle Swarms (DOPS): a meta-heuristic for parameter estimation in biochemical models

Background

Mathematical modeling is a powerful tool to analyze, and ultimately design biochemical networks. However, the estimation of the parameters that appear in biochemical models is a significant challenge. Parameter estimation typically involves expensive function evaluations and noisy data, making it difficult to quickly obtain optimal solutions. Further, biochemical models often have many local extrema which further complicates parameter estimation. Toward these challenges, we developed Dynamic Optimization with Particle Swarms (DOPS), a novel hybrid meta-heuristic that combined multi-swarm particle swarm optimization with dynamically dimensioned search (DDS). DOPS uses a multi-swarm particle swarm optimization technique to generate candidate solution vectors, the best of which is then greedily updated using dynamically dimensioned search.

Results

We tested DOPS using classic optimization test functions, biochemical benchmark problems and real-world biochemical models. We performed \(\mathcal {T}\) = 25 trials with \(\mathcal {N}\) = 4000 function evaluations per trial, and compared the performance of DOPS with other commonly used meta-heuristics such as differential evolution (DE), simulated annealing (SA) and dynamically dimensioned search (DDS). On average, DOPS outperformed other common meta-heuristics on the optimization test functions, benchmark problems and a real-world model of the human coagulation cascade.

Conclusions

DOPS is a promising meta-heuristic approach for the estimation of biochemical model parameters in relatively few function evaluations. DOPS source code is available for download under a MIT license at http://www.varnerlab.org.

     

A school-curriculum-based exercise intervention program for two years in pre-pubertal girls does not influence hip structure

Background

It is known that physical activity during growth has a positive influence on bone mineral accrual, and is thus possibly one strategy to prevent osteoporosis. However, as bone geometry, independent of areal bone mineral density (aBMD), influences fracture risk, this study aimed to evaluate whether hip structure in pre-pubertal girls is also affected by a two-year exercise intervention program.

Methods

Forty-two girls aged 7–9 years in a school-curriculum-based exercise intervention program comprising 40 minutes of general physical activity per school day (200 minutes per week) were compared with 43 age-matched girls who participated in the general Swedish physical education curriculum comprising a mean of 60 minutes per week. The hip was scanned by dual energy X-ray absorptiometry (DXA) and the hip structural analysis (HSA) software was applied to evaluate bone mineral content (BMC, g), areal bone mineral density (aBMD, g/cm²), periosteal diameter, cross-sectional area (CSA, cm²), section modulus (Z, cm³) and cross-sectional moment of inertia (CSMI, cm⁴) of the femoral neck (FN). Annual changes were compared. Subjective duration of physical activity was estimated by questionnaire and objective level of everyday physical activity at follow-up by means of accelerometers worn for four consecutive days. All children remained at Tanner stage 1 throughout the study. Group comparisons were made by independent student's t-test between means and analyses of covariance (ANCOVA).

Results

At baseline, the two groups did not differ with regard to age, anthropometrics or bone parameters. No between-group differences were observed for annual changes in the FN variables measured.

Conclusion

A two-year school-based moderately intense general exercise program for 7–9-year-old pre-pubertal girls does not influence structural changes in the FN.

     

A quality improvement program for adolescents with cystic fibrosis: focus on psychosocial skills

Background

The two pediatric cystic fibrosis centers (CFCs) in Paris (Robert Debré) and Nantes, France, have been developing therapeutic patient education (TPE) programs since 2006 and have been engaged in the pilot phase of the quality improvement program (QIP) named the Hospital Program to Improve Outcomes and Expertise in Cystic Fibrosis (PHARE-M) since 2011. The objective was to improve the FEV1 of the cohort of adolescents to prepare them for their optimal transition to an adult CFC.

Methods

The two CFCs formed a multidisciplinary quality team and used the analysis of causes of insufficient respiratory function taking into account the adolescents’ psychosocial factors. At the Nantes CFC, the approach was centered on adolescents’ body image and their motivation to take care of themselves by assigning specific aspects of patient follow-up to each professional in the team. At R. Debré, an individual cause-and-effect diagram identified for each patient the medical and psychosocial factors that could account for insufficient respiratory function. Personalized actions were offered to each patient.

Results

In 2014, the median FEV1 (Forced Expiratory Volume in 1 Second) of the adolescent cohort exceeds 90% at the 2 CFCs (Nantes and R. Debré). Between 2011 and 2014 both centers improved their ranking for FEV1% in adolescents in the Registry histograms. At R. Debré, the personalized process allowed to reinforce equality of care, offering to all the opportunity to benefit from TPE sessions and coaching with an adapted physical activity teacher. The psychologist developed a specific tool to support the patient-centered process.

Conclusion

The link between TPE and QIP was strong at our two centers enhancing patient centered care and targeting an optimal transition to an adult program.

     

A novel application of capnography during controlled human exposure to air pollution

Background

A detailed contrast bolus propagation model is essential for optimizing bolus-chasing Computed Tomography Angiography (CTA). Bolus characteristics were studied using bolus-timing datasets from Magnetic Resonance Angiography (MRA) for adaptive controller design and validation.

Methods

MRA bolus-timing datasets of the aorta in thirty patients were analyzed by a program developed with MATLAB. Bolus characteristics, such as peak position, dispersion and bolus velocity, were studied. The bolus profile was fit to a convolution function, which would serve as a mathematical model of bolus propagation in future controller design.

Results

The maximum speed of the bolus in the aorta ranged from 5–13 cm/s and the dwell time ranged from 7–13 seconds. Bolus characteristics were well described by the proposed propagation model, which included the exact functional relationships between the parameters and aortic location.

Conclusion

The convolution function describes bolus dynamics reasonably well and could be used to implement the adaptive controller design.     

Improved identifiability of myocardial material parameters by an energy-based cost function

Myocardial stiffness is a valuable clinical biomarker for the monitoring and stratification of heart failure (HF). Cardiac finite element models provide a biomechanical framework for the assessment of stiffness through the determination of the myocardial constitutive model parameters. The reported parameter intercorrelations in popular constitutive relations, however, obstruct the unique estimation of material parameters and limit the reliable translation of this stiffness metric to clinical practice. Focusing on the role of the cost function (CF) in parameter identifiability, we investigate the performance of a set of geometric indices (based on displacements, strains, cavity volume, wall thickness and apicobasal dimension of the ventricle) and a novel CF derived from energy conservation. Our results, with a commonly used transversely isotropic material model (proposed by Guccione et al.), demonstrate that a single geometry-based CF is unable to uniquely constrain the parameter space. The energy-based CF, conversely, isolates one of the parameters and in conjunction with one of the geometric metrics provides a unique estimation of the parameter set. This gives rise to a new methodology for estimating myocardial material parameters based on the combination of deformation and energetics analysis. The accuracy of the pipeline is demonstrated in silico, and its robustness in vivo, in a total of 8 clinical data sets (7 HF and one control). The mean identified parameters of the Guccione material law were \(C_1=3000\pm 1700\,\hbox {Pa}\) and \(\alpha =45\pm 25\) (\(b_f=25\pm 14\), \(b_{ft}=11\pm 6\), \(b_{t}=9\pm 5\)) for the HF cases and \(C_1=1700\,\hbox {Pa}\) and \(\alpha =15\) (\(b_f=8\), \(b_{ft}=4\), \(b_{t}=3\)) for the healthy case.     

Introduction of a collaborative quality improvement program in the French cystic fibrosis network: the PHARE-M initiative

Background

An agreement, signed in 2007 by the 49 French Cystic Fibrosis Centers, included a commitment to participate, within the next 5 years, in a care quality assessment and improvement program (QIP). The objective was to roll out in the French Cystic Fibrosis (CF) care network a QIP adapted from the US program for Accelerating Improvement in Cystic Fibrosis Care developed by The Dartmouth Institute Microsystem Academy (TDIMA) and customized by the US CF Foundation between 2002 and 2013.

Methods

The French national team at the Nantes-Roscoff CF Center of Expertise was trained at TDIMA and visited US CF centers involved in US Learning and Leadership Collaboratives (LLCs). It introduced the PHARE-M QIP in France by transposing the Action Guide and material. A PHARE-M LLC1 including seven centers, underwent two external assessments. Adjustments were made, then a PHARE-M LLC2 was rolled out at seven more centers in two regions. On-site coaching was strengthened. The teams’ satisfaction was assessed and further adjustments were made. In 2014, the program sought recognition as a continuing education program for healthcare professionals.

Results

Ninety-six trainees including 14 patients/parents from the 14 CFCs volunteered to participate, test and adapt the program during LLC1 and LLC2 sessions. Comparison of patient outcomes collected in the Registry report by CF center, reflection on potential best practices, selection by each team of an improvement theme, implementation of improvement actions, and exchanges between teams fostered the adhesion of the teams. The program strengthened quality of care, interdisciplinary functioning and collaboration with patients/parents at the centers. The satisfaction expressed by the teams increased over time. A post-PHARE-M cycle maintains the focus on continuous quality improvement (CQI). In 2015, PHARE-M was recognized as a continuing professional development program in healthcare.

Conclusions

The PHARE-M is a complex intervention in multidisciplinary teams working in a variety of hospital settings. A confluence of factors motivated teams to engage in the program. Involving Patient/Parent in quality improvement (QI) work and developing patient therapeutic education for self-management appeared to be complementary approaches to improve care. Incorporating the program into hospital continuing education insures its sustainability. Transparency of Patient Registry indicators per center published in a brief lapse of time is required to effectively support CQI. The impact of the PHARE-M on patient outcomes after 3 years is the subject of a research program funded by the French Ministry of Health whose results will be available in 2017.

     

A quality improvement program to improve nutritional status of children with Cystic Fibrosis aged 2-12 years old over a 3 year period at CF center Roscoff,Brittany

Background

The Cystic Fibrosis (CF) center in Roscoff (Brittany) has been involved in therapeutic education programs (TEP) since 2006 and took part in the pilot phase of the French quality improvement program (QIP) since 2011. The aim was to improve the nutritional status of children with cystic fibrosis aged 2-12 years old in order to optimize their health status as they enter adolescence.

Methods

A multidisciplinary quality team was created in order to select and address a specific health problem among our pediatric population. Following analysis of yearly indicators for our CF center, our team chose to improve quality of care concerning nutritional status of children aged 2-12 years old. Factors influencing efficacy were studied, tools were developed to implement a new nutritional program, results were analyzed on a real-time basis.

Results

Over the 3 year period, all patients from 2 years of age, were monitored with the new follow-up program (2012: N =?34; 2014: N =?44). Each patient was followed up at every clinic visit, their BMI z-score was calculated to decide their nutritional risk and personalize their follow-up program consequently. Between 1/1/2012 and 31/12/2014, the mean BMI z-score of the open cohort improved from ?0.49 to ?0.22.

Conclusions

Since 2014, focus on nutrition using the newly-adapted program has become routine practice at each follow-up visit. Patients and parents expressed a high level of satisfaction (75% very satisfied). The follow-up program aimed at improving nutritional status for children aged 2-12 years old was successfully implemented and integrated into routine practice; it was therefore extended to all children with CF (1 month - 18 years) in our center. The relationship among professional and patients and parents was strengthened.

     

Assessment of right atrium dysfunction in patients with obstructive sleep apnea syndrome using velocity vector imaging

Background and Objectives

This study aimed to assess the changes of RA function in patients with obstructive sleep apnea syndrome (OSAS) using velocity vector imaging (VVI) and to evaluate the application of VVI technology.

Methods

According to the apnea–hypopnea index (AHI), 71 patients with OSAS were divided into three groups: mild, moderate, and severe. A total of 30 cases of healthy subjects were enrolled as the control group. Digital images of apex four-chamber views were acquired to measure the right atrium (RA) linear dimensions and volume parameters including RA longitudinal diameter (RAL), transverse diameter (RAT), RA maximum volume (Vmax), RA minimum volume (Vmin), right atrial volume before contraction (Vpre). Right atrial volume parameters were corrected by body surface area (VImax, VImin, VIpre). The total right atrial emptying fraction (RATEF), right atrial passive emptying fraction (RAPEF), right atrial active contraction emptying fraction (RAAEF) were calculated. The VVI data measuring right atrial global strain (RA-GLS), right atrial strain rate in ventricular systolic phase (RA-SRs), right atrial strain rate in ventricular early diastolic phase (RA-SRe), right atrial strain rate in ventricular late diastolic phase (RA-SRa).

Results

1. 1.
   RA linear dimensions and volume parameters in severe OSAS were higher than those of control group. RAPEF in severe group was lower than control group and mild OSAS group (t?= 2.681, P?=?0.021; t?= 2.985, P?=?0.011; respectively). RAAEF in OSAS moderate group was higher than that of control group (t?= 3.006, P?=?0.02), and without statistical difference (P?>?0.05) in the severe OSAS group and the control group.
    
2. 2.
   RA-GLS in moderate OSAS group was significantly lower than that of control group (t?= 2.333, P?=?0.040) and reduced more obvious in the severe OSAS group (vs control, t?= 3.25, P?=?0.008, vs mild; t?= 3.011, P?=?0.012; respectively). RA-SRe in moderate and severe OSAS groups were lower than control group (t?= 2.466, P?=?0.031; t?= 3.547, P?=?0.005; respectively). RA-SRs of OSAS in severe group was lower than that of control and mild groups (t?= 3.665, P?=?0.004; t?= 3.204, P?=?0.008; respectively). RA-SRa in severe OSAS group was lower than that of control group (t?= 2.425, P?=?0.034).
    
3. 3.
   Multivariate regression analysis showed that RA-GLS and RA-SRe were independently correlated with AHI (t?=???2.738, P?=?0.010; t?=???2.191, P?=?0.036; respectively).
    

Conclusion

RA function was impaired in patients with OSAS. On hemodynamics, the change of RA function performed increased of reserve function, reduced pipeline function and increased of contraction function. However, the strain and strain rate reduced in different degree. RA-GLS and RA-SRe decreased the earliest, which suggested that strain and strain rate were the parameters which can reflect myocardial function damage earliest. VVI can more earlier and accurately detect myocardial dysfunction of right atrium in patients with OSAS, which is expected to be a worthy technique for early clinical therapy in patients with OSAS.

     

Robust dose-response curve estimation applied to high content screening data analysis

Background and method

Successfully automated sigmoidal curve fitting is highly challenging when applied to large data sets. In this paper, we describe a robust algorithm for fitting sigmoid dose-response curves by estimating four parameters (floor, window, shift, and slope), together with the detection of outliers. We propose two improvements over current methods for curve fitting. The first one is the detection of outliers which is performed during the initialization step with correspondent adjustments of the derivative and error estimation functions. The second aspect is the enhancement of the weighting quality of data points using mean calculation in Tukey’s biweight function.

Results and conclusion

Automatic curve fitting of 19,236 dose-response experiments shows that our proposed method outperforms the current fitting methods provided by MATLAB®;’s nlinfit nlinfit function and GraphPad’s Prism software.

     

Coupling effects on turning points of infectious diseases epidemics in scale-free networks

Background

Pandemic is a typical spreading phenomenon that can be observed in the human society and is dependent on the structure of the social network. The Susceptible-Infective-Recovered (SIR) model describes spreading phenomena using two spreading factors; contagiousness (β) and recovery rate (γ). Some network models are trying to reflect the social network, but the real structure is difficult to uncover.

Methods

We have developed a spreading phenomenon simulator that can input the epidemic parameters and network parameters and performed the experiment of disease propagation. The simulation result was analyzed to construct a new marker VRTP distribution. We also induced the VRTP formula for three of the network mathematical models.

Results

We suggest new marker VRTP (value of recovered on turning point) to describe the coupling between the SIR spreading and the Scale-free (SF) network and observe the aspects of the coupling effects with the various of spreading and network parameters. We also derive the analytic formulation of VRTP in the fully mixed model, the configuration model, and the degree-based model respectively in the mathematical function form for the insights on the relationship between experimental simulation and theoretical consideration.

Conclusions

We discover the coupling effect between SIR spreading and SF network through devising novel marker VRTP which reflects the shifting effect and relates to entropy.