bluuebunny/crossref_metadata_2025 huggingface dataset:
Endovascular Treatment of Transplant Renal Artery Stenosis: A Systematic Review and Meta-analysis
Authors: Hinojosa-Gonzalez David Eugenio , Salgado-Garza Gustavo , Torres-Martinez Mauricio , Villegas-De Leon Sergio Uriel , Bueno-Gutierrez Luis Carlos , Herrera-Carrillo Francisco Eugenio , Gonzalez-Urquijo Mauricio , Segura Ibarra Victor , Fabiani Mario Alejandro , Flores-Villalba Eduardo
Published: August 2021

Objective

Endovascular treatment through either percutaneous transluminal angioplasty (PTA) alone or stenting has been previously used as a treatment for transplant renal artery stenosis (TRAS). This review aimed to investigate the results of endovascular treatment for renal artery stenosis in transplanted kidneys as compared with the outcomes of interventions, medical management, and graft survival in non-TRAS patients.

Methods

A systematic review of PubMed, Google Scholar, Cochrane, and Scopus was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines in which studies that reported outcomes of the treatment of TRAS via the endoluminal approach were identified, and their results were meta-analyzed.

Results

Fifty-four studies with a total of 1522 patients were included. A significant reduction of serum creatinine level was found, favoring the stenting group, with a mean difference of 0.68 mg/dL (95% confidence interval (CI), 0.17–1.19; Z=2.60, p=0.0009). Comparison of pre- and post-intervention values of any intervention revealed a significant decrease in overall serum creatinine level (0.65 mg/dL; 95% CI, 0.40–0.90; Z=5.09, p=0.00001), overall blood pressure, with a mean difference of 11.12 mmHg (95% CI, 7.29–14.95; Z=5.59, p=0.00001), mean difference in the use of medications (0.77; 95% CI, 0.29–1.24; p=0.002), and peak systolic velocity (190.05; 95% CI, 128.41–251.69; p<0.00001). The comparison of serum creatinine level between endovascular interventions and best medical therapy favored endovascular intervention, with a mean difference of 0.23 mg/dL (95% CI, 0.14–0.32; Z=5.07, p<0.00001). Graft survival was similar between the treated patients and those without TRAS (hazard ratio, 0.98; 95% CI, 0.75–1.28; p=0.091). The overall pooled success rate was 89%, and the overall complication rate was 10.4%, with the most prevalent complication being arterial dissection.

Conclusion

The endovascular treatment of TRAS improves graft preservation and renal function and hemodynamic parameters. PTA + stenting appears to be a more effective option to PTA alone in the stabilization of renal function, with additional benefits from decreased restenosis rates. Further high-quality studies could expand on these findings.
Utilization of multilayer perceptron for determining the inverse kinematics of an industrial robotic manipulator
Authors: Šegota Sandi Baressi , Anđelić Nikola , Mrzljak Vedran , Lorencin Ivan , Kuric Ivan , Car Zlatan
Published: August 2021

Inverse kinematic equations allow the determination of the joint angles necessary for the robotic manipulator to place a tool into a predefined position. Determining this equation is vital but a complex work. In this article, an artificial neural network, more specifically, a feed-forward type, multilayer perceptron (MLP), is trained, so that it could be used to calculate the inverse kinematics for a robotic manipulator. First, direct kinematics of a robotic manipulator are determined using Denavit–Hartenberg method and a dataset of 15,000 points is generated using the calculated homogenous transformation matrices. Following that, multiple MLPs are trained with 10,240 different hyperparameter combinations to find the best. Each trained MLP is evaluated using the R 2 and mean absolute error metrics and the architectures of the MLPs that achieved the best results are presented. Results show a successful regression for the first five joints (percentage error being less than 0.1%) but a comparatively poor regression for the final joint due to the configuration of the robotic manipulator.
Social-emotional problems of children with mild intellectual disabilities having parents with mental health concerns: A quantitative comparison study
Authors: Riemersma I , Van Santvoort F , Van Doesum KTM , Hosman CMH , Janssens JMAM , Weeland M , Otten R
Published: August 2021

Introduction:

Children of parents with mental health concerns are at-risk for social-emotional problems. In this study, we assessed whether children with a mild intellectual disability and parents with mental health concerns are particularly at-risk.

Method:

Strengths and Difficulties Questionnaire (SDQ) reports of children with a mild intellectual disability (N = 55) and their parents with mental health concerns (N = 45) were compared to two comparison groups. The first group included children with average intelligence (N = 13) and their parents with mental health concerns (N = 56), the second group included children with mild intellectual disability (N = 44) and their parents (N = 36).

Results:

Children with a mild intellectual disability and a parent with mental health concerns show higher total SDQ problem scores and more internalizing and externalizing problems as compared to children in the two other groups.

Discussion:

Children having mild intellectual disability and parents with mental health concerns are particularly at risk for developing social-emotional problems.
Development and Validation of Computational Thinking Assessment of Chinese Elementary School Students
Authors: Li Yan , Xu Shan , Liu Jia
Published: August 2021

Recent advances in artificial intelligence have brought attention to computational thinking (CT) in school education worldwide. However, little is known about the development of the literacy of CT in children, mainly because of the lack of proper psychometric assessments. We developed the first psychometrically validated assessment on the literacy of CT of children in Chinese elementary schools, coined as the Computational Thinking Assessment for Chinese Elementary Students (CTA-CES). Items were constructed to reflect key aspects of CT such as abstraction, algorithm thinking, decomposition, evaluation, and pattern recognition. To examine the test reliability and validity, we recruited two samples of 280 third- to sixth-grade students in total. Cronbach’s alpha provided evidence for the reliability of the test scores, item response theory analyses demonstrated psychometric appropriateness, whereas construct validity was verified by convergent validity, and criterion-related validity was confirmed by correlations between the CTA-CES and measures related to CT, namely reasoning, spatial ability, and verbal ability. In addition, an fMRI study further demonstrated similar neural activation patterns when students conducted the CTA-CES and programming tasks. Taken together, the CTA-CES is the first reliable and valid instrument for measuring the literacy of CT for Chinese children, and may be applicable to children worldwide.
A dialogue system for identifying need deficiencies in moral education
Authors: Chen Penghe , Lu Yu , Yu Shengquan , Xu Qi , Liu Jiefei
Published: August 2021

Moral education refers to the cultivation of ideals, moral quality, culture, and discipline. One of its main tasks is to analyze students’ problem behaviors and identify their underlying need deficiencies. Previous psychological research has focused on studying how distinct factors affect psychological needs and problem behaviors. However, these findings have provided only scattered guidelines for identifying students’ need deficiencies, which are difficult for inexperienced teachers and parents to apply systematically. To address these issues, we attempt to answer two key research questions in this work. First, how do we define a theoretical framework so that the psychological research findings can be systematically applied to identify students’ need deficiencies? Second, can the latest AI technologies be employed to identify such need deficiencies automatically? To answer these research questions, we first build a theoretical framework to summarize all the factors relevant to the students’ problem behaviors and need deficiencies. After that, we propose and develop a task-oriented dialogue system that can properly inquire about different aspects of students’ information and automatically infer their need deficiencies. We conduct comprehensive experiments to evaluate the system’s performance with real-life cases. The results show that the built dialogue system could effectively serve as a diagnostic tool to identify the students’ need deficiencies.
Justice and Inclusion Mutually Cause Each Other
Authors: Martin Chris C. , Zyphur Michael J.
Published: August 2021

Justice should increase inclusion because just treatment conveys acceptance and enables social exchanges that build cohesion. Inclusion should increase justice because people can use inclusion as a convenient fairness cue. Prior research touches on these causal associations but relies on a thin conception of inclusion and neglects within-person effects. We analyze whether justice causes inclusion at the within-person level. Five waves of data were gathered from 235 college students in 38 entrepreneurial teams. Teams were similar in size, work experience, deadlines, and goals. General cross-lagged panel models indicated that justice and inclusion had a reciprocal influence on each other. A robustness check with random-intercept cross-lagged models supported the results. In the long run, reversion to the mean occurred after an effect decayed, suggesting that virtuous or vicious cycles are unlikely. The results imply that maintaining overall justice at the peer-to-peer level may lead to inclusion.
To Pursue or Not to Pursue STEM? Faculty Behavior Enhances Student Involvement in STEM Roles by Signaling Role-Specific Support
Authors: Norman Jasmine B. , Fuesting Melissa A. , Geerling Danielle M. , Chen Jacqueline M. , Gable Shelly L. , Diekman Amanda B.
Published: August 2021

Four studies examine the faculty–student relationship as a mechanism through which students ascertain their place in science, technology, engineering, and mathematics (STEM) fields. Studies 1 and 2 use experimental methods to demonstrate STEM faculty who behave communally, relative to independently, increase undergraduates’ belonging and interest in STEM roles through anticipation of greater role-specific support (i.e., support that emphasizes guiding students through structures and activities of field-specific roles). Study 3 then examined the consequences of role-specific support for undergraduates’ belonging and interest in STEM. Students anticipated more belonging and interest in STEM roles when faculty provided high levels of role-specific support. Finally, STEM doctoral students’ perception of role-specific support from faculty related to their belonging and future identification in STEM fields (Study 4). Taken together, these studies demonstrate the importance of students’ construals of role-specific support from faculty, and how faculty behavior signals role-specific support, with benefits for student involvement in STEM.
Association of the rate of bilirubin decrease with major morbidity in patients undergoing preoperative biliary drainage before pancreaticoduodenectomy
Authors: Rungsakulkij Narongsak , Thongchai Varinthip , Suragul Wikran , Vassanasiri Watoo , Tangtawee Pongsatorn , Muangkaew Paramin , Mingphruedhi Somkit , Aeesoa Suraida
Published: August 2021

Objective:

The objective of this study was to examine the relationship between the rate of bilirubin decrease following preoperative biliary drainage before pancreaticoduodenectomy and postoperative morbidity.

Methods:

Records of patients who underwent pancreaticoduodenectomy at the Department of Surgery in Ramathibodi Hospital between January 2008 and December 2019 were retrospectively reviewed. The patients were classified into either an adequate or inadequate drainage rate groups according to the bilirubin decrease rate. Major morbidity was defined as higher than grade II in the Clavien-Dindo classification. Risk factors for major morbidity were analyzed by logistic regression analysis.

Results:

In total, 166 patients were included in the study. Major morbidity was observed in 36 patients (21.6%). Adequate biliary drainage rate was observed in 39 patients (23.4%). Patients who had major morbidity were less likely to have come from the adequate biliary drainage rate group than the inadequate group (38.9% vs. 61.1%). However, through multivariate logistic analysis, only body mass index, operative time, and pancreatic duct diameter were independent factors associated with major morbidity, whereas the bilirubin decrease rate was not.

Conclusions:

Bilirubin decrease rate following preoperative biliary drainage has no significant association with major postoperative morbidity after pancreaticoduodenectomy.
Politics and Politeness: Analysis of Incivility on Twitter During the 2020 Democratic Presidential Primary
Authors: Trifiro Briana M. , Paik Sejin , Fang Zhixin , Zhang Li
Published: August 2021

In the past decade, social networking sites have become central forums for public discourse and political engagement. Of particular interest is the role that Twitter plays in the facilitation of political discourse. To this end, the existing literature argues that a healthy political discussion space is key to maintaining a trusting and robust democratic society. Using Suler’s online disinhibition effect as a theoretical orientation, this study seeks to address the extent of incivility on Twitter in discourse regarding the top three 2020 Democratic primary candidates. A total corpus of 18,237,296 tweets was analyzed in an effort to assess the extent to which incivility dominated Twitter discourse surrounding these candidates. Our results reveal that tweets that mention Senator Elizabeth Warren were associated with higher levels of uncivil discourse than tweets that mentioned Senator Bernie Sanders and former Vice President Joe Biden. Interestingly, there does not appear to be a relationship with anonymity and incivility, as uncivil tweets were just as likely to originate from tweets that identified users’ names as they were to originate from anonymous or pseudonymous accounts. Finally, our findings provide evidence that certain policy issues are more closely related to uncivil discourse than others. Through the use of k-means clustering, our findings illustrate that the issue of gun control and immigration is closely related with mentions of Warren and fiscal policy with Sanders; however, we did not find any policy keywords linked to Biden.
Melatonin ameliorates hepatic steatosis by inhibiting NLRP3 inflammasome in db/db mice
Authors: Yu Yongxiang , Chen Dongru , Zhao Yuhua , Zhu Jianjun , Dong Xiaohui
Published: August 2021

Introduction: Type 2 diabetes mellitus (T2DM) is commonly accompanied by obesity and non-alcoholic fatty liver disease (NAFLD), yet the mechanism underlying diabetes-related NAFLD is not fully understood. It has been reported that melatonin can regulate glucose and lipid metabolism. This study aims to investigate the actions and mechanisms of melatonin toward the development of diabetes-related NAFLD. Methods: Melatonin (bid, 30 mg/kg/day, i.p.) was administrated to db/db mice for 8 weeks, while saline was administrated to db/m mice. The metabolic parameters of mice were measured using an automatic biochemistry analyzer. The oxidative stress indexes and mitochondrial membrane potential (MMP) were determined with kits. Pathological assessment in liver tissues was used to analyze the effects of melatonin on hepatic steatosis. The levels of IL-1β and IL-18 were detected with ELISA kits. The mRNA levels of NLRP3 inflammasome were detected using quantitative real-time PCR assay, and protein expressions were estimated using Western blotting assay. Immunofluorescence staining was used to evaluate the caspase-1 expression in the liver. Results: Melatonin treatment significantly reduced blood glucose, serum insulin, body weight, related liver weight, serum lipids, and hepatic enzymes in db/db mice. Melatonin markedly corrected the NAFLD phenotypes, including lipid accumulation, steatohepatitis, fibrosis, and oxidative stress levels. Melatonin significantly improved the MMP level and decreased the serum IL-1β and IL-18 concentrations. The mRNA levels of the NLRP3 inflammasome could also be remarkably reversed by melatonin in the liver tissues. The activation of the NLRP3 inflammasome was also suppressed, evidenced by the downregulated proteins of NLRP3, caspase-1, IL-1β, and IL-18. The enhanced fluorescence intensity of caspase-1 in the liver tissues was also obviously weakened by the melatonin treatment. Conclusion: Our study concluded that melatonin could safeguard against NAFLD by improving hepatic steatosis in db/db mice, and this action could be associated with the regulation of the NLRP3 inflammasome activation.
The Influence of Psychological Capital on Employees’ Innovative Behavior: Mediating Role of Employees’ Innovative Intention and Employees’ Job Satisfaction
Authors: Alshebami Ali Saleh
Published: August 2021

The study investigates the impact of psychological capital on the employees’ innovative behavior through the mediating effect of employees’ job satisfaction and employees’ innovative intention in the small and medium enterprises (SMEs) sector of Saudi Arabia. A sample of 204 respondents participated from various enterprises working without restricting specific sectors to check employees’ common behavior in multiple sectors. The data and hypotheses testing analysis were made with the partial least squares–based structural equation modeling (PLS-SEM). The study revealed that psychological capital positively affects employees’ job satisfaction, innovative behavior, and innovative intention. Furthermore, the employees’ job satisfaction also positively correlated with the employees’ innovative behavior, while there was no connection between the employees’ innovative intention and the employees’ innovative behavior. Concerning the indirect relationships, the findings revealed that employees’ job satisfaction played a partial mediating role between psychological capital and the employees’ innovative behavior. However, the employees’ innovative intention did not mediate the relationship between the psychological capital and the employees’ innovative behavior. These findings suggest the importance of psychological capital in influencing the innovative behavior of employees. Hence, there is a need to continue developing it among employees to ensure a better output.
Risk of Infection in Knee Arthroscopy Patients Undergoing Corticosteroid Injections in the Perioperative Period
Authors: Belk John W. , Keeling Laura E. , Kraeutler Matthew J. , Snow Michaela G. , Mei-Dan Omer , Scillia Anthony J. , McCarty Eric C.
Published: August 2021

Background:

Recent evidence suggests that there may be an increased risk of infection for patients undergoing a corticosteroid injection before, during, or after knee arthroscopy.

Purpose:

To systematically review the literature to evaluate the risk of postoperative infection in patients undergoing intra-articular corticosteroid injections (CSI) before, during, or after knee arthroscopy.

Study Design:

Systematic review; Level of evidence, 3.

Methods:

A systematic review was performed by searching the PubMed, Cochrane Library, and Embase databases to identify studies that evaluated the rate of postoperative infection in patients undergoing knee arthroscopy who received an intra-articular CSI during the perioperative period. The search phrase used was “knee AND arthroscopy AND injection AND (infection OR revision).” A subanalysis was also performed to analyze infection rates based on the timing of the corticosteroid injection in relation to arthroscopy.

Results:

Four studies met the inclusion criteria, representing 11,925 patients undergoing knee arthroscopy with an intra-articular CSI administered during the perioperative period (mean follow-up, 5.3 months) and 247,329 patients without a corticosteroid injection during the perioperative period (mean follow-up, 5.9 months). Patients who received an injection experienced a statistically significantly higher rate of postoperative infection (2.2%) when compared with patients who did not receive an injection (1.1%; P < .001). When analyzed by the timing of the injection, patients receiving an injection preoperatively or intraoperatively experienced a statistically significantly higher rate of postoperative infection (3% and 2.6%, respectively) when compared with patients receiving an injection postoperatively (1.4%; P = .001 for both).

Conclusion:

Patients undergoing knee arthroscopy who receive an intra-articular CSI during the perioperative period can be expected to experience significantly higher postoperative infection rates when compared with patients not receiving an injection. Furthermore, patients receiving a corticosteroid injection pre- or intraoperatively may experience significantly higher rates of postoperative infection when compared with patients receiving an injection postoperatively.
“It’s Just Always Eating”: The Experiences of Young People Growing up Medium Chain Acyl-coA Dehydrogenase Deficiency
Authors: Piercy Hilary , Nutting Charlotte , Yap Sufin
Published: August 2021

Medium chain acyl-CoA dehydrogenase deficiency (MCADD) is a rare metabolic disorder, and commonly now part of newborn screening programs. Those diagnosed at birth are now progressing from childhood to adulthood. The study aim was to explore young people’s experiences of living with MCADD and managing their condition. A descriptive qualitative study design involving semi-structured interviews with 12 participants aged 10 to 15 years, recruited from one regional pediatric metabolic disorder service in England. Data were analyzed using thematic analysis. The two major themes were “Eating for energy” and “Growing into a self-management role.” Self-monitoring and self-management skills had been nurtured from early childhood by parents and healthcare providers. Young people’s anxieties concerned having to maintain adequate energy input to stay safe and the associated burden of responsibility. Growing up with MCADD presents specific challenges. Self-management and ongoing support are important for dealing with those challenges.
The GPCR adaptor protein norbin suppresses the neutrophil-mediated immunity of mice to pneumococcal infection
Authors: Pantarelli Chiara , Pan Dingxin , Chetwynd Stephen , Stark Anne-Katrien , Hornigold Kirsti , Machin Polly , Crossland Laraine , Cleary Simon J. , Baker Martin J. , Hampson Elizabeth , Mandel Anna , Segonds-Pichon Anne , Walker Rachael , van ’t Veer Cornelis , Riffo-Vasquez Yanira , Okkenhaug Klaus , Pitchford Simon , Welch Heidi C.E.
Published: August 2021

Streptococcal pneumonia is a worldwide health problem that kills ∼2 million people each year, particularly young children, the elderly, and immunosuppressed individuals. Alveolar macrophages and neutrophils provide the early innate immune response to clear pneumococcus from infected lungs. However, the level of neutrophil involvement is context dependent, both in humans and in mouse models of the disease, influenced by factors such as bacterial load, age, and coinfections. Here, we show that the G protein–coupled receptor (GPCR) adaptor protein norbin (neurochondrin, NCDN), which was hitherto known as a regulator of neuronal function, is a suppressor of neutrophil-mediated innate immunity. Myeloid norbin deficiency improved the immunity of mice to pneumococcal infection by increasing the involvement of neutrophils in clearing the bacteria, without affecting neutrophil recruitment or causing autoinflammation. It also improved immunity during Escherichia coli–induced septic peritonitis. It increased the responsiveness of neutrophils to a range of stimuli, promoting their ability to kill bacteria in a reactive oxygen species–dependent manner, enhancing degranulation, phagocytosis, and the production of reactive oxygen species and neutrophil extracellular traps, raising the cell surface levels of selected GPCRs, and increasing GPCR-dependent Rac and Erk signaling. The Rac guanine-nucleotide exchange factor Prex1, a known effector of norbin, was dispensable for most of these effects, which suggested that norbin controls additional downstream targets. We identified the Rac guanine-nucleotide exchange factor Vav as one of these effectors. In summary, our study presents the GPCR adaptor protein norbin as an immune suppressor that limits the ability of neutrophils to clear bacterial infections.
Long-term effect of hematopoietic cell transplantation on systemic inflammation in patients with mucopolysaccharidoses
Authors: van den Broek Brigitte T.A. , Lindemans Caroline A. , Boelens Jaap Jan , Delemarre Eveline M. , Drylewicz Julia , Verhoeven-Duif Nanda , van Hasselt Peter M. , Nierkens Stefan
Published: August 2021

Mucopolysaccharidoses (MPS) are devastating inherited diseases treated with hematopoietic cell transplantation (HCT). However, disease progression, especially skeletal, still occurs in all patients. Secondary inflammation has been hypothesized to be a cause. To investigate whether systemic inflammation is present in untreated patients and to evaluate the effect of HCT on systemic inflammation, dried blood spots (n = 66) of patients with MPS (n = 33) treated with HCT between 2003 and 2019 were included. Time points consisted of pre-HCT and, for patients with MPS type I (MPS I), also at 1, 3, and 10 years of follow-up. Ninety-two markers of the OLINK inflammation panel were measured and compared with those of age-matched control subjects (n = 31) by using principal component analysis and Wilcoxon rank sum tests with correction. Median age at transplantation was 1.3 years (range, 0.2-4.8 years), and median time of pre-HCT sample to transplantation was 0.1 year. Normal leukocyte enzyme activity levels were achieved in 93% of patients post-HCT. Pretransplant samples showed clear separation of patients and control subjects. Markers that differentiated pre-HCT between control subjects and patients were mainly pro-inflammatory (50%) or related to bone homeostasis and extracellular matrix degradation (33%). After 10 years’ follow-up, only 5 markers (receptor activator of nuclear factor kappa-Β ligand, osteoprotegerin, axis inhibition protein 1 [AXIN1], stem cell factor, and Fms-related tyrosine kinase 3 ligand) remained significantly increased, with a large fold change difference between patients with MPS I and control subjects. In conclusion, systemic inflammation is present in untreated MPS patients and is reduced upon treatment with HCT. Markers related to bone homeostasis remain elevated up to 10 years after HCT and possibly reflect the ongoing skeletal disease, making them potential biomarkers for the evaluation of new therapies.
Bayesian Hodges-Lehmann tests for statistical equivalence in the two-sample setting: Power analysis, type I error rates and equivalence boundary selection in biomedical research
Authors: Kelter Riko
Published: August 2021

Background

Null hypothesis significance testing (NHST) is among the most frequently employed methods in the biomedical sciences. However, the problems of NHST andp-values have been discussed widely and various Bayesian alternatives have been proposed. Some proposals focus on equivalence testing, which aims at testing an interval hypothesis instead of a precise hypothesis. An interval hypothesis includes a small range of parameter values instead of a single null value and the idea goes back to Hodges and Lehmann. As researchers can always expect to observe some (although often negligibly small) effect size, interval hypotheses are more realistic for biomedical research. However, the selection of an equivalence region (the interval boundaries) often seems arbitrary and several Bayesian approaches to equivalence testing coexist.

Methods

A new proposal is made how to determine the equivalence region for Bayesian equivalence tests based on objective criteria like type I error rate and power. Existing approaches to Bayesian equivalence testing in the two-sample setting are discussed with a focus on the Bayes factor and the region of practical equivalence (ROPE). A simulation study derives the necessary results to make use of the new method in the two-sample setting, which is among the most frequently carried out procedures in biomedical research.

Results

Bayesian Hodges-Lehmann tests for statistical equivalence differ in their sensitivity to the prior modeling, power, and the associated type I error rates. The relationship between type I error rates, power and sample sizes for existing Bayesian equivalence tests is identified in the two-sample setting. Results allow to determine the equivalence region based on the new method by incorporating such objective criteria. Importantly, results show that not only can prior selection influence the type I error rate and power, but the relationship is even reverse for the Bayes factor and ROPE based equivalence tests.

Conclusion

Based on the results, researchers can select between the existing Bayesian Hodges-Lehmann tests for statistical equivalence and determine the equivalence region based on objective criteria, thus improving the reproducibility of biomedical research.
Two-stage sampling in the estimation of growth parameters and percentile norms: sample weights versus auxiliary variable estimation
Authors: Vamvakas George , Norbury Courtenay , Pickles Andrew
Published: August 2021

Background

The use of auxiliary variables with maximum likelihood parameter estimation for surveys that miss data by design is not a widespread approach, despite its documented improved efficiency over traditional approaches that deploy sampling weights. Although efficiency gains from the use of Normally distributed auxiliary variables in a model have been recorded in the literature, little is known about the effects of non-Normal auxiliary variables in the parameter estimation.

Methods

We simulate growth data to mimic SCALES, a two-stage survey of language development with a screening phase (stage one) for which data are observed for the whole sample and an intensive assessments phase (stage two), for which data are observed for a sub-sample, selected using stratified random sampling. In the simulation, we allow a fully observed Poisson distributed stratification criterion to be correlated with the partially observed model responses and develop five generalised structural equation growth models that host the auxiliary information from this criterion. We compare these models with each other and with a weighted growth model in terms of bias, efficiency, and coverage. We finally apply our best performing model to SCALES data and show how to obtain growth parameters and population norms.

Results

Parameter estimation from a model that incorporates a non-Normal auxiliary variable is unbiased and more efficient than its weighted counterpart. The auxiliary variable method is capable of producing efficient population percentile norms and velocities.

Conclusions

The deployment of a fully observed variable that dominates the selection of the sample and correlates strongly with the incomplete variable of interest appears beneficial for the estimation process.
Modeling of atrophy size trajectories: variable transformation, prediction and age-of-onset estimation
Authors: Behning Charlotte , Fleckenstein Monika , Pfau Maximilian , Adrion Christine , Goerdt Lukas , Lindner Moritz , Schmitz-Valckenberg Steffen , Holz Frank G , Schmid Matthias
Published: August 2021

Background

To model the progression of geographic atrophy (GA) in patients with age-related macular degeneration (AMD) by building a suitable statistical regression model for GA size measurements obtained from fundus autofluorescence imaging.

Methods

Based on theoretical considerations, we develop a linear mixed-effects model for GA size progression that incorporates covariable-dependent enlargement rates as well as correlations between longitudinally collected GA size measurements. To capture nonlinear progression in a flexible way, we systematically assess Box-Cox transformations with different transformation parametersλ. Model evaluation is performed on data collected for two longitudinal, prospective multi-center cohort studies on GA size progression.

Results

A transformation parameter ofλ=0.45 yielded the best model fit regarding the Akaike information criterion (AIC). When hypertension and hypercholesterolemia were included as risk factors in the model, they showed an association with progression of GA size. The mean estimated age-of-onset in this model was 67.21±6.49 years.

Conclusions

We provide a comprehensive framework for modeling the course of uni- or bilateral GA size progression in longitudinal observational studies. Specifically, the model allows for age-of-onset estimation, identification of risk factors and prediction of future GA size. A square-root transformation of atrophy size is recommended before model fitting.
Uterine fibroids and risk of preterm birth by clinical subtypes: a prospective cohort study
Authors: Sundermann Alexandra C. , Aldridge Tiara D. , Hartmann Katherine E. , Jones Sarah H. , Torstenson Eric S. , Edwards Digna R. Velez
Published: August 2021

Background

Fibroids are present in approximately one in ten pregnancies and are inconsistently linked with preterm birth. We sought to determine the association between fibroids and preterm birth in a prospective cohort with standardized research ultrasounds for characterizing fibroids in early pregnancy while accounting for the clinical paths that precede preterm birth.

Methods

Participants who were pregnant or planning a pregnancy were recruited from communities in three states between 2000 and 2012. Members of this prospective cohort had a research ultrasound in the first trimester to establish pregnancy dating and to record detailed information about the presence, size, number, and location of fibroids. Baseline information from time of enrollment and a detailed first trimester interview contributed key information about candidate confounders. Birth outcomes, including clinical classification of type of preterm birth (preterm labor, preterm premature rupture of membranes, and medically indicated preterm birth) were cross-validated from participant report, labor and delivery records, and birth certificate data.

Results

Among 4,622 women with singleton pregnancies, 475 had at least one fibroid (10.3%) and 352 pregnancies resulted in preterm birth (7.6%). Prevalence of fibroids was similar for women with preterm and term births (10.2% vs. 10.3%). Fibroids were not associated with increased risk of preterm birth after taking into account confounding (risk ratio adjusted for race/ethnicity and maternal age, 0.88; 95% confidence interval, 0.62–1.24) nor any clinical subtype of preterm birth. No fibroid characteristic or combination of characteristics was associated with risk.

Conclusions

If fibroids increase risk of preterm birth, the effect is substantially smaller than previous estimates. Given lack of effect in a large population of women from the general population, rather than higher risk academic tertiary populations previously most studied, we encourage a reconsideration of the clinical impression that presence of fibroids is a major risk factor for preterm birth.
The role of complement factor H in gestational diabetes mellitus and pregnancy
Authors: Li Junxian , Shen Ying , Tian Hairong , Xie Shuting , Ji Ye , Li Ziyun , Lu Junxi , Lu Huijuan , Liu Bo , Liu Fang
Published: August 2021

Background

Complement factor H (CFH) has been found to be associated with insulin resistance. This study assessed the correlation between CFH and other clinical parameters, and determined whether CFH played a role in gestational diabetes mellitus (GDM) and adverse pregnancy outcomes.

Methods

A total of 397 pregnant women were included for analysis in this nested case-control study. Clinical parameters and serum were collected within the 11-17th gestational age at the first prenatal visit. At 24–28 weeks of gestation, a 75 g oral glucose tolerance test was performed and subjects were divided into a GDM (n = 80) and a non-GDM control group (n = 317). The delivery data were also followed. The serum CFH level was assayed by ELISA.

Results

CFH was higher in GDM than in non-GDM controls (280.02 [58.60] vs. 264.20 [68.77];P = 0.014). CFH level was moderately associated with pre-pregnancy body mass index (BMI), BMI and total triglycerides (TG), and slightly associated with gestational age, low density lipoprotein cholesterol (LDL-C), total cholesterol (TC) in GDM and non-GDM (allP <  0.05). Moreover, CFH level was moderately correlated with alkaline phosphatase (ALP) and slightly correlated with age, uric acid (UA) and total bilirubin (TB) in non-GDM (allP <  0.05). After adjustment for clinical confounding factors, BMI, TG, gestational age, ALP, TB, age and UA were independent risk factors for log10CFH levels (allP <  0.05) in all subjects. In addition, overweight or obese pregnant women, women with hypertriglyceridemia and women in the second trimester had significantly higher CFH levels than normal weight and underweight group (P <  0.001), the non-hypertriglyceridemia group (P <  0.001) and women in the first trimester group (P < 0.05) in all pregnant women respectively. Following binary logistic regression, CFH was not independently associated with GDM and related pregnant outcomes.

Conclusions

The CFH in 11-17th weeks of gestation might be affected by many factors, including BMI, TG, gestational age, ALP, TB, age and UA. CFH was not an independent risk factor for GDM and avderse pregnancy outcomes.
Postpartum septic pelvic thrombophlebitis and ovarian vein thrombosis after caesarean section: a rare case report
Authors: Shi Qin , Gandi Deborah Shulamite , Hua Yurong , Zhu Yi , Yao Jinhan , Yang Xiaoqing , Xu Yunzhao , Zhang Yuquan
Published: August 2021

Background

Septic pelvic thrombophlebitis (SPT) is a well-recognized but rare puerperal complication that has two types: ovarian vein thrombophlebitis (OVT) and deep septic pelvic thrombophlebitis (DSPT). The present case report describes the clinical and imaging findings of a female patient diagnosed with right ovarian vein infectious thrombophlebitis after caesarean section (C-section).

Case presentation

A 35-year-old G3P2 female who presented with a foetal vein Galen malformation at 41 weeks of gestation underwent C-section. The patient had high fever after C-section, and anti-inflammatory treatment was not effective within 1 week. An abdominal wall incision haematoma was found, and a second surgery for the removal of the abdominal wall haematoma was performed. The patient was ultimately diagnosed with abdominal incision haematoma and right ovarian vein infectious thrombophlebitis after C-section. We used imipenem and tigecycline to strengthen the anti-inflammatory effects, simultaneously administrating low-molecular-weight heparin and warfarin as anticoagulant therapy. On the 30th day after C-section, the right ovarian vein thrombus disappeared.

Conclusion

This case illustrates the need to consider the potential relationship between abdominal incision haematoma and ovarian vein thrombophlebitis. Despite advances in the management of venous thromboembolism globally, more data on epidemiology in terms of first incidence, prevalence, recurrence and risk factors, management of bleeding complications, and increased awareness in Asian populations are necessary.
What is beyond Salmonella gastroenteritis? A case of acute pancreatitis complicating Salmonella infection in a child: a case report and literature review
Authors: Al Kaabi Salwa , Al Kaabi Aysha , Al Nuaimi Hasa
Published: August 2021

Background

Salmonella infection presents itself in a wide variety of ways, ranging from mild self-limited illness to severe systemic disease with multiorgan involvement. Acute pancreatitis (AP) is a very rare complication that is associated with Salmonella infection, especially among the pediatric population.

Case presentation

A five-year-old boy presented with a two-day fever and experienced vomiting, diarrhea, and abdominal pain. The boy was admitted as a case of acute gastroenteritis, and Salmonella was found in his stool culture. The severity of his abdominal pain during his hospital stay indicated the possibility of AP. A clinical examination and blood workup were performed and showed significant elevation in amylase and lipase, which confirmed the diagnosis of AP.

Conclusion

Although abdominal pain is a common presentation of Salmonella infection, the possibility of AP must be considered when the pain is severe and the characteristics of the pain are suggestive of AP. Herein, we report a case of AP complicating Salmonella infection in an immunocompetent child.
Joint trajectories of life style indicators and their links to psychopathological outcomes in the adolescence
Authors: Zhang Anhui , Fang Jiao , Wan Yuhui , Su Puyu , Tao Fangbiao , Sun Ying
Published: August 2021

Background

Rapid socio-economic development makes China a unique laboratory for examining how lifestyle changes affect adolescent mental health. This study aims to identify joint trajectories of modifiable lifestyle indicators during pubertal transition and its associations with psychopathological outcomes.

Methods

A cohort of 1974 children aged 7–9 years were recruited in Anhui Province, China during March 2013. The assessment of lifestyle behaviors (screen time, physical activity, sleep duration and beverage intake) and depressive symptoms were conducted from Wave 1 to Wave 4 (2018). Suicide ideation, non-suicidal self-harm (NSSI) and alcohol use were self-reported at Wave 4. Longitudinal trajectories of lifestyle patterns were defined using group-based multi-trajectory models in 2019.

Results

Four lifestyle trajectories were identified: persistent healthy (39.9%), suboptimal healthy (25.3%), unhealthy mitigation (17.2%), and persistent unhealthy (17.7%). Compared with persistent healthy group, the risk of subsequent suicide ideation [odds ratio (OR): 2.86, 95%CI: 2.15–3.81], depressive symptoms (OR: 2.16, 95%CI: 1.39–3.35), alcohol use (OR: 2.53, 95%CI: 1.78–3.61) and non-suicidal self-harm (OR: 1.35, 95%CI: 1.09–1.67) was significantly higher in persistent unhealthy group.

Conclusions

This study provided convincing evidence that unhealthy lifestyle trajectory during adolescence is associated with more than two-fold elevated odds for multiple domains of psychopathological outcomes over 5 years.
Prevalence and clinical consequences of atelectasis in SARS-CoV-2 pneumonia: a computed tomography retrospective cohort study
Authors: Mingote Álvaro , Albajar Andrea , García Benedito Paulino , Garcia-Suarez Jessica , Pelosi Paolo , Ball Lorenzo , García-Fernández Javier
Published: August 2021

Background

The aim of the study is to estimate the prevalence of atelectasis assessed with computer tomography (CT) in SARS-CoV-2 pneumonia and the relationship between the amount of atelectasis with oxygenation impairment, Intensive Care Unit admission rate and the length of in-hospital stay.

Patients and methods

Two-hundred thirty-seven patients admitted to the hospital with SARS-CoV-2 pneumonia diagnosed by clinical, radiology and molecular tests in the nasopharyngeal swab who underwent a chest computed tomography because of a respiratory worsening from Apr 1 to Apr 30, 2020 were included in the study. Patients were divided into three groups depending on the presence and amount of atelectasis at the computed tomography: no atelectasis, small atelectasis (< 5% of the estimated lung volume) or large atelectasis (> 5% of the estimated lung volume). In all patients, clinical severity, oxygen-therapy need, Intensive Care Unit admission rate, the length of in-hospital stay and in-hospital mortality data were collected.

Results

Thirty patients (19%) showed small atelectasis while eight patients (5%) showed large atelectasis. One hundred and seventeen patients (76%) did not show atelectasis. Patients with large atelectasis compared to patients with small atelectasis had lower SatO2/FiO2 (182 vs 411 respectively, p = 0.01), needed more days of oxygen therapy (20 vs 5 days respectively, p = 0,02), more frequently Intensive Care Unit admission (75% vs 7% respectively, p < 0.01) and a longer period of hospitalization (40 vs 14 days respectively p < 0.01).

Conclusion

In patients with SARS-CoV-2 pneumonia, atelectasis might appear in up to 24% of patients and the presence of larger amount of atelectasis is associated with worse oxygenation and clinical outcome.
The role of cerebrospinal fluid cross-section area ratio in the prediction of dural ossification and clinical outcomes in patients with thoracic ossification of ligamentum flavum
Authors: Zhai Jiliang , Guo Shigong , Zhao Yu , Li Chunxu , Niu Tong
Published: August 2021

Background

It is imperative to preoperatively distinguish dural ossification (DO) and thus anticipate the risks and outcome of the surgery for patients with ossification of ligamentum flavum (OLF). However, studies have disagreed as to the efficacy of the radiographic signs or factors to predict DO and surgical outcome. In additon, the association between the cerebrospinal fluid cross-section area ratio (CCAR) and DO or clinical outcome had not been reported. The purpose of this study was to analyse CCAR and its role in prediction of DO and neurological function recovery rate in patients with OLF.

Methods

Fifty-two consecutive patients with OLF, who underwent posterior thoracic decompression and fusion between September 2012 and March 2019 at a single institution, were retrospectively reviewed. Demographic data, radiographic signs of DO, CCAR, pre- and postoperative modified Japanese Orthopedic Association (mJOA) score were recorded.

Results

There were 27 patients in the DO group and 25 patients in the non-DO group, with a mean age at surgery of 57.4 years and 53.9 years, respectively. No significant differences were found in sex, age, segment of maximum compression and preoperative mJOA score between the two groups. The receiver operating characteristic curve showed that the value of CCAR had a relatively high value for diagnosis of DO and prediction of neurological function recovery rate (P = .000). According to the value of CCAR, three zones were defined as DO zone (≤14.3%), non-DO zone (≥44.5%), and gray zone (14.3 to 44.5%). When the value of CCAR≤14.3%, the recovery rate was poor or fair, while it had good or excellent recovery when CCAR≥45.2%.

Conclusion

The value of CCAR had a high diagnostic value for prediction of DO and neurological function recovery rate in patients with OLF.