Tag: statistics

Eur Endod J. 2021 Aug;6(2):197-204. doi: 10.14744/eej.2021.10437.

ABSTRACT

OBJECTIVE: TruNatomy and XP-endo Shaper are recently introduced file systems showing increased fatigue resistance rate. The present study aims to evaluate the surface topographic changes and nickel (Ni) and titanium (Ti) elemental loss of XP-endo Shaper (XPS) and TruNatomy (TN) files on exposure to conventionally used root canal irrigants; [5.25% sodium hypochlorite (NaOCl) and 17% ethylenediaminetetraacetic acid (EDTA)] at a 10 minute time frame using atomic force microscopy (AFM) and energy dispersion X-ray spectroscopy (EDX) analytical techniques.

METHODS: Twelve samples for each of XPS (30/.04 taper) and TN (26/.04 taper; prime) instruments were dynamically exposed to 5.25% NaOCl, 17% EDTA separately for 10 minutes and in combination of 5.25% NaOCl (8 minutes)+17% EDTA (2 minutes) for a total of 10 minutes. Post exposure, the files were subjugated to AFM and EDX analysis. Independent t test and one-way ANOVA were used for statistical analysis, and the level of significance was set at 0.05.

RESULTS: XPS and TN showed a significant increase of surface roughness (Ra) and roughness mean square (RMS) on exposure to various irrigants (P<0.05) using AFM analysis. Increased overall roughness was observed with TN in comparison to XPS (P<0.05). Elements Ni and Ti loss was found in both XPS and TN files using EDX analysis. Both files exhibited Ni and Ti loss with the loss of Ni content higher for TN after exposure to 17% EDTA. Loss of Ti was seen for both files on exposure to a combination of 5.25% NaOCl+17% EDTA.

CONCLUSION: After exposure to root canal irrigants, the surface roughness was lesser in XPS compared to TN files. 17% EDTA caused significantly higher surface roughness in both file systems when compared to 5.25% NaOCl. TN exhibited overall higher elemental (Ni and Ti) loss on exposure to 17% EDTA and 5.25% NaOCl+17% EDTA in comparison to XPS files.

PMID:34650015 | DOI:10.14744/eej.2021.10437

Eur Respir J. 2021 Oct 14:2101574. doi: 10.1183/13993003.01574-2021. Online ahead of print.

ABSTRACT

BACKGROUND: High-flow nasal cannula (HFNC) has become a frequently used non-invasive form of respiratory support in acute settings, however evidence supporting its use has only recently emerged. These guidelines provide evidence-based recommendations for the use of HFNC alongside other noninvasive forms of respiratory support in adults with acute respiratory failure (ARF).

MATERIALS AND METHODOLOGY: The European Respiratory Society Task Force panel included expert clinicians and methodologists in pulmonology and intensive care medicine. The Task Force used the GRADE (Grading of Recommendations, Assessment, Development, and Evaluations) methods to summarise evidence and develop clinical recommendations for the use of HFNC alongside conventional oxygen therapy (COT) and non-invasive ventilation (NIV) for the management of adults in acute settings with ARF.

RESULTS: The Task Force developed 8 conditional recommendations, suggesting using: 1) HFNC over COT in hypoxemic ARF, 2) HFNC over NIV in hypoxemic ARF, 3)HFNC over COT during breaks from NIV, 4) either HFNC or COT in post-operative patients at low risk of pulmonary complications, 5) either HFNC or NIV in post-operative patients at high risk of pulmonary complications, 6) HFNC over COT in non-surgical patients at low risk of extubation failure, 7) NIV over HFNC for patients at high risk of extubation failure unless there are relative or absolute contraindications to NIV, 8) trialling NIV prior to use of HFNC in patients with chronic obstructive pulmonary disease (COPD) and hypercapnic ARF.

CONCLUSIONS: HFNC is a valuable intervention in adults with ARF. These conditional recommendations can assist clinicians in choosing the most appropriate form of non-invasive respiratory support to provide to patients in different acute settings.

PMID:34649974 | DOI:10.1183/13993003.01574-2021

Pediatrics. 2021 Oct 14:e2020033878. doi: 10.1542/peds.2020-033878. Online ahead of print.

ABSTRACT

OBJECTIVES: With the Children with Hemiparesis Arm and Hand Movement Project (CHAMP) multisite factorial randomized controlled trial, we compared 2 doses and 2 constraint types of constraint-induced movement therapy (CIMT) to usual customary treatment (UCT).

METHODS: CHAMP randomly assigned 118 2- to 8-year-olds with hemiparetic cerebral palsy to one of 5 treatments with assessments at baseline, end of treatment, and 6 months posttreatment. Primary blinded outcomes were the assisting hand assessment; Peabody Motor Development Scales, Second Edition, Visual Motor Integration; and Quality of Upper Extremity Skills Test Dissociated Movement. Parents rated functioning on the Pediatric Evaluation of Disabilities Inventory-Computer Adaptive Test Daily Activities and Child Motor Activity Log How Often scale. Analyses were focused on blinded and parent-report outcomes and rank-order gains across all measures.

RESULTS: Findings varied in statistical significance when analyzing individual blinded outcomes. parent reports, and rank-order gains. Consistently, high-dose CIMT, regardless of constraint type, produced a pattern of greatest short- and long-term gains (1.7% probability of occurring by chance alone) and significant gains on visual motor integration and dissociated movement at 6 months. O’Brien’s rank-order analyses revealed high-dose CIMT produced significantly greater improvement than a moderate dose or UCT. All CIMT groups improved significantly more in parent-reported functioning, compared with that of UCT. Children with UCT also revealed objective gains (eg, 48% exceeded the smallest-detectable assisting hand assessment change, compared with 71% high-dose CIMT at the end of treatment).

CONCLUSIONS: CHAMP provides novel albeit complex findings: although most individual blinded outcomes fell below statistical significance for group differences, high-dose CIMT consistently produced the largest improvements at both time points. An unexpected finding concerns shifts in UCT toward higher dosages, with improved outcomes compared with previous reports.

PMID:34649982 | DOI:10.1542/peds.2020-033878

Eur Respir J. 2021 Oct 14:2102099. doi: 10.1183/13993003.02099-2021. Online ahead of print.

NO ABSTRACT

PMID:34649973 | DOI:10.1183/13993003.02099-2021

Biotechnol J. 2021 Oct 14:e2100414. doi: 10.1002/biot.202100414. Online ahead of print.

ABSTRACT

BACKGROUND: Recent technological advancements in synthetic and systems biology have enabled the construction of microbial cell factories expressing diverse heterologous pathways in unprecedentedly short time scales. However, the translation of such laboratory scale breakthroughs to industrial bioprocesses remains a major bottleneck.

METHODS AND MAJOR RESULTS: In this study, an accelerated bioprocess development approach was employed to optimize the biosynthetic pathway of the blockbuster chemotherapy drug, Taxol. Statistical design of experiments approaches were coupled with an industrially relevant high-throughput microbioreactor system to optimize production of key Taxol intermediates, Taxadien-5α-ol and Taxadien-5α-yl-acetate, in engineered yeast cell factories. The optimal factor combination was determined via data driven statistical modelling and validated in 1L bioreactors leading to a 2.1-fold improvement in taxane production compared to a typical defined media. Elucidation and mitigation of nutrient limitation enhanced product titers a further two-fold and titers of the critical Taxol precursors, Taxadien-5α-ol and Taxadien-5α-yl-acetate were improved to 34 and 11 mg/L, representing a three-fold improvement compared to the highest literature titers in S. cerevisiae. Comparable titers were obtained when the process was scaled up a further five-fold using 5L bioreactors.

CONCLUSIONS: The results of this study highlight the benefits of a holistic design of experiments guided approach to expedite early stage bioprocess development. This article is protected by copyright. All rights reserved.

PMID:34649302 | DOI:10.1002/biot.202100414

Stat Med. 2021 Oct 14. doi: 10.1002/sim.9214. Online ahead of print.

ABSTRACT

Alzheimer’s disease (AD) is a severe neurodegenerative disorder impairing multiple domains, for example, cognition and behavior. Assessing the risk of AD progression and initiating timely interventions at early stages are critical to improve the quality of life for AD patients. Due to the heterogeneous nature and complex mechanisms of AD, one single longitudinal outcome is insufficient to assess AD severity and disease progression. Therefore, AD studies collect multiple longitudinal outcomes, including cognitive and behavioral measurements, as well as structural brain images such as magnetic resonance imaging (MRI). How to utilize the multivariate longitudinal outcomes and MRI data to make efficient statistical inference and prediction is an open question. In this article, we propose a multivariate joint model with functional data (MJM-FD) framework that relates multiple correlated longitudinal outcomes to a survival outcome, and use the scalar-on-function regression method to include voxel-based whole-brain MRI data as functional predictors in both longitudinal and survival models. We adopt a Bayesian paradigm to make statistical inference and develop a dynamic prediction framework to predict an individual’s future longitudinal outcomes and risk of a survival event. We validate the MJM-FD framework through extensive simulation studies and apply it to the motivating Alzheimer’s Disease Neuroimaging Initiative (ADNI) study.

PMID:34649301 | DOI:10.1002/sim.9214

Med Sci Sports Exerc. 2021 Jul 7. doi: 10.1249/MSS.0000000000002739. Online ahead of print.

ABSTRACT

PURPOSE: To describe changes in laboratory-assessed anthropometric and physiological characteristics, training volumes and competitive performance in national development-team cross-country (XC) skiers over a 25-month period, and to analyze whether changes in competitive performance could be predicted by changes in laboratory-assessed qualities and training volumes.

METHODS: Data collected over 25 months from 30 national development-team XC skiers (14 women, 16 men; age 18-23 y) were analyzed retrospectively using multivariate statistics. Anthropometric and physiological characteristics were assessed via dual-energy X-ray absorptiometry and incremental roller-ski treadmill tests, respectively. Total training volumes and distributions of low- and high-intensity training (LIT and HIT) were analyzed from online training diaries, and competitive performance was determined by International Ski Federation (FIS) distance and sprint points.

RESULTS: Whole- and upper-body lean mass increased in the full cohort of skiers (n = 30; both p < 0.05), while lower-body lean mass, whole-body fat mass, speed and oxygen uptake (V˙O2) at a blood lactate concentration (BLa) of 2 and 4 mmol·L-1, as well as time-trial (TT) completion time, power output and peak V˙O2, improved in the women only (all p < 0.05). Valid predictive models were identified for female skiers’ best FIS distance points (R2 = 0.81 / Q2 = 0.51) and changes in FIS distance points (R2 = 0.83 / Q2 = 0.54), with body mass, fat mass, lean mass, V˙O2peak and speed at a BLa of 4 mmol·L-1 identified as consistently important variables for projection.

CONCLUSION: The valid prediction of competitive performance was achieved for women only in distance events. This study suggests that improvements in body composition and aerobic capacity may be more beneficial for elite female development-level skiers than for their male counterparts. These results have implications for athlete selection and performance development.

PMID:34649265 | DOI:10.1249/MSS.0000000000002739

Rofo. 2021 Oct 14. doi: 10.1055/a-1545-4983. Online ahead of print.

ABSTRACT

PURPOSE: To evaluate the use of ultrasound (US) during catheter placement in interstitial brachytherapy (iBT) of abdominal malignancies as an alternative to computed tomography (CT) fluoroscopy.

MATERIALS AND METHODS: Catheter placement for CT-guided iBT was, if US visibility was sufficient, assisted by sonography in 52 consecutive patients with 82 lesions (liver N = 62; kidney N = 16; peritoneum N = 4) of various malignancies. We collected data on lesion visibility, location, depth, size, and dosimetry. Comparison of CT fluoroscopy versus US-assisted catheter placement was performed by Fisher’s exact test for frequencies and U-test for lesion visibility and dosimetric data. Factors predicting the utility of sonography were determined in a lesion-based multivariate regression analysis. A p-value < 0.05 was regarded as statistically significant.

RESULTS: 150 catheters (1 to 6 per lesion; mean diameter 3.6 ± 2.4 cm) were implanted. CT fluoroscopy was used for 44 catheters, and US was used for 106 catheters. Lesion visibility assessed by 5-point Likert scale was significantly better in US (median 2 vs. 3; p = 0.011) and effective dose was significantly reduced if US guidance was applicable (median 1.75 vs. 8.19 mSv; p = 0.014). In a multivariate regression analysis, we identified increased lesion size and caudal location within the target organ to independently predict the utility of ultrasound in catheter placement for iBT.

CONCLUSION: Sonography is a helpful technique to assist CT-guided interstitial brachytherapy of upper abdominal malignancies. Especially for larger lesions localized in the lower liver segments or lower half of the kidney, superior visibility can be expected. As the effective dose of the patient is also reduced, radiation exposure of the medical staff may be indirectly lowered.

KEY POINTS: · Ultrasound-assisted catheter placement in CT-guided brachytherapy of upper abdominal malignancies significantly improves lesion visibility.. · Predictors of successful ultrasound application are larger lesions within the lower portion of the liver and kidney.. · By reducing the need for CT fluoroscopy during intervention, radiation exposure to the medical staff may be indirectly lowered..

CITATION FORMAT: · Damm R, Damm R, Heinze C et al. Radioablation of Upper Abdominal Malignancies by CT-Guided, Interstitial HDR Brachytherapy: A Multivariate Analysis of Catheter Placement Assisted by Ultrasound Imaging. Fortschr Röntgenstr 2021; DOI: 10.1055/a-1545-4983.

PMID:34649287 | DOI:10.1055/a-1545-4983

Dement Geriatr Cogn Disord. 2021 Oct 14:1-6. doi: 10.1159/000519581. Online ahead of print.

ABSTRACT

INTRODUCTION: Although early diagnosis has been recognized as a key strategy to improve outcomes of Alzheimer’s disease and related dementias (ADRD), the effect of receiving a diagnosis on patients’ well-being is not well understood. This study addresses this gap by examining if receiving a dementia diagnosis influences social relationships.

METHODS: Data from the 3 waves (2012, 2014, and 2016) of the Health and Retirement Study were utilized as part of this study. This study examined whether receiving a new diagnosis of ADRD changed subsequent social relationships (social networks, social engagement, and social support). Regression analyses with inverse probability weighting were performed to estimate the impact of receiving a dementia diagnosis on changes in social relationships.

RESULTS: Receiving a new diagnosis of ADRD reduced both informal and formal social engagement. We found no statistically significant impacts of receiving a diagnosis of ADRD on social networks and social support.

CONCLUSIONS: Results suggest that receiving a new diagnosis of ADRD may have unintended impacts on social relationships. Practitioners and policymakers should be aware of these consequences and should identify strategies to alleviate the negative impact of receiving a diagnosis of ADRD and methods to mobilize support networks after receiving a diagnosis.

PMID:34649243 | DOI:10.1159/000519581

Physiol Meas. 2021 Oct 14. doi: 10.1088/1361-6579/ac2fb7. Online ahead of print.

ABSTRACT

OBJECTIVE: The aim of this study was to find spectral differences of diagnostic interest in heart sound recordings of patients with coronary artery disease (CAD) and healthy subjects.

APPROACH: Heart sound recordings from three studies were pooled, and patients with clear diagnostic outcomes (positive: CAD and negative: Non-CAD) were selected for further analysis. Recordings from 1146 patients (191 CAD and 955 Non-CAD) were analyzed for spectral differences between the two groups using Welch’s spectral density estimate. Frequency spectra were estimated for systole and diastole segments, and time-frequency spectra were estimated for first (S1) and second (S2) heart sound segments. An ANCOVA model with terms for diagnosis, age, gender, and body mass index (BMI) was used to evaluate statistical significance of the diagnosis term for each time-frequency component.

MAIN RESULTS: Diastole and systole segments of CAD patients showed increased energy at frequencies 20-120 Hz; furthermore, this difference was statistically significant for the diastole. CAD patients showed decreased energy for the mid-S1 and mid-S2 segments and conversely increased energy before and after the valve sounds. Both S1 and S2 segments showed regions of statistically significant difference in the time-frequency spectra.

SIGNIFICANCE: Results from analysis of the diastole support findings of increased low-frequency energy from previous studies. Time-frequency components of S1 and S2 sounds showed that these two segments likely contain heretofore untapped information for risk assessment of CAD using phonocardiography; this should be considered in future works. Further development of features that build on these findings could lead to improved acoustic detection of CAD.

PMID:34649235 | DOI:10.1088/1361-6579/ac2fb7