Solving large-scale MEG/EEG source localisation and functional connectivity problems simultaneously using state-space models.

State-space models are widely employed across various research disciplines to study unobserved dynamics. Conventional estimation techniques, such as Kalman filtering and expectation maximisation, offer valuable insights but incur high computational costs in large-scale analyses. Sparse inverse covariance estimators can mitigate these costs, but at the expense of a trade-off between enforced sparsity and increased estimation bias, necessitating careful assessment in low signal-to-noise ratio (SNR) situations. To address these challenges, we propose a three-fold solution: (1) Introducing multiple penalised state-space (MPSS) models that leverage data-driven regularisation; (2) Developing novel algorithms derived from backpropagation, gradient descent, and alternating least squares to solve MPSS models; (3) Presenting a K-fold cross-validation extension for evaluating regularisation parameters. We validate this MPSS regularisation framework through lower and more complex simulations under varying SNR conditions, including a large-scale synthetic magneto- and electro-encephalography (MEG/EEG) data analysis. In addition, we apply MPSS models to concurrently solve brain source localisation and functional connectivity problems for real event-related MEG/EEG data, encompassing thousands of sources on the cortical surface. The proposed methodology overcomes the limitations of existing approaches, such as constraints to small-scale and region-of-interest analyses. Thus, it may enable a more accurate and detailed exploration of cognitive brain functions.

Characteristics and predictors of chronic kidney disease in children with myelomeningocele: a nationwide cohort study.

BACKGROUND: Myelomeningocele (MMC) is highly prevalent in developing countries, and MMC-related neurogenic bladder is an important cause of childhood chronic kidney disease (CKD). This nationwide study aimed to evaluate demographic and clinical features of pediatric patients with MMC in Turkey and risk factors associated with CKD stage 5. METHODS: Data from children aged 0-19 years old, living with MMC in 2022, were retrospectively collected from 27 pediatric nephrology centers. Patients > 1 year of age without pre-existing kidney abnormalities were divided into five groups according to eGFR; CKD stages 1-5. Patients on dialysis, kidney transplant recipients, and those with eGFR < 15 ml/min/1.73 m2 but not on kidney replacement therapy at time of study constituted the CKD stage 5 group. RESULTS: A total of 911 (57.8% female) patients were enrolled, most of whom were expectantly managed. Stages 1-4 CKD were found in 34.3%, 4.2%, 4.1%, and 2.4%, respectively. CKD stage 5 was observed in 5.3% of patients at median 13 years old (range 2-18 years). Current age, age at first abnormal DMSA scan, moderate-to-severe trabeculated bladder on US and/or VCUG, and VUR history were independent risk factors for development of CKD stage 5 (OR 0.752; 95%; CI 0.658-0.859; p < 0.001; OR 1.187; 95% CI 1.031-1.367; p = 0.017; OR 10.031; 95% CI 2.210-45.544; p = 0.003; OR 2.722; 95% CI 1.215-6.102; p = 0.015, respectively). Only eight CKD stage 5 patients underwent surgery related to a hostile bladder between 1 and 15 years old. CONCLUSION: MMC-related CKD is common in childhood in Turkey. A proactive approach to neurogenic bladder management and early protective surgery in selected cases where conservative treatment has failed should be implemented to prevent progressive kidney failure in the pediatric MMC population in our country.

Dietary acid load in children with chronic kidney disease: its association with nutritional status and health-related quality of life.

BACKGROUND: This study aimed to determine the dietary acid load of children with chronic kidney disease (CKD) and to evaluate the relationship between dietary acid load, nutritional status, and health-related quality of life (HRQOL). METHOD: A total of 67 children aged 3-18 years with a diagnosis of CKD stages II-V were included in the study. Anthropometric measurements (body weight, height, mid-upper arm circumference, waist, and neck circumference) and 3-day food consumption records were taken to evaluate the nutritional status. The net endogenous acid production (NEAP) score was calculated to determine the dietary acid load. "Pediatric Inventory of Quality of Life (PedsQL)" was used to assess the participants' HRQOL. RESULTS: The mean NEAP was 59.2 ± 18.96 mEq/day. Stunted and malnourished children had significantly higher NEAP than those who were not (p < 0.05). There were no significant differences in terms of HRQOL scores according to NEAP groups. The multivariate logistic regression analysis showed that waist circumference (OR: 0.890, 95% CI: 0.794-0.997), serum albumin (OR: 0.252, 95% CI: 0.068-0.929), and glomerular filtration rate (GFR) (OR: 0.985, 95% CI: 0.970-1.000) were negatively associated with high NEAP. CONCLUSION: This study shows that a diet shifted in an acidic direction in children with CKD and a higher dietary acid load are associated with lower serum albumin, GFR, and waist circumference, but not HRQOL. These results suggest that dietary acid load might affect nutritional status and CKD progression in children with CKD. Future studies with larger samples are needed to confirm these results and to understand underlying mechanisms. A higher resolution version of the Graphical abstract is available as Supplementary information.

Epicardial adipose tissue and risk of arrhythmia in nephrotic syndrome.

BACKGROUND: Patients with nephrotic syndrome (NS) are at a high risk of cardiovascular disease, obesity, and dyslipidemia. The aim of this study was to evaluate the formation of epicardial adipose tissue (EAT) and investigate electrocardiographic (ECG) parameters in patients. METHODS: Thirty-two patients aged 0-18 years and 15 control patients were compared. In the patient group, physical examination and laboratory parameters were recorded. Atrial depolarization and ventricular repolarization parameters in ECG were compared between the groups. EAT was evaluated with M-mode measurements on echocardiography. RESULTS: There was no difference between the groups in terms of sex, age, body mass index, systolic and diastolic BP. EAT was found to be significantly higher in the patient group. In ECG evaluations it was determined that atrial depolarization and ventricular repolarization parameters increased in the patient group. CONCLUSIONS: Cardiovascular morbidity and mortality are high in kidney diseases. Measurement and follow-up of EAT and ECG findings as a noninvasive parameter can provide information in NS.

Is coronavirus pandemic-related anxiety higher in children with chronic kidney disease than healthy children?

BACKGROUND: Since the emergence and worldwide spread of the new coronavirus (COVID-19) pandemic, it has caused people to experience adverse psychological effects. This study aimed to assess anxiety levels during COVID-19 in children with chronic kidney disease (CKD), including nephrotic syndrome (NS) and kidney transplantation (Tx). METHODS: A case-controlled, cross-sectional study was conducted with children aged 10-18 years, who had a diagnosis of CKD or NS, or Tx, and followed in our center between April and July 2020. A healthy control group was recruited with age- and gender-matched children. A questionnaire with printed and online versions was designed in three parts: the first addressed demographic characteristics, the second addressed opinions about the pandemic, and the third was the Turkish version of the Revised Child Anxiety and Depression Scale - Child Version. RESULTS: A total of 88 children completed the questionnaire. The patient and control groups were similar in terms of gender, age, household members and history of psychiatric treatment. Both groups stated that coronavirus is a risky disease for children (63.6%), and that they were afraid of contagion (69.3%). Only half of them were receiving realistic and informative answers from family members. In the Revised Child Anxiety and Depression Scale - Child Version, 66% of them received a high score on at least one subscale. The social phobia scores of the control group were higher than those of the patient group, although the proportion of high scores was similar in both groups. The ratio of high-scored participants was higher in CKD patients for panic disorder, and was lower in the immunosuppressive agent group for social phobia. CONCLUSION: The current COVID-19 pandemic is a disaster that children encounter for the first time in their lives. It does not exclusively cause anxiety among children with chronic kidney diseases but also affects healthy children.

The Effect of "Unclassified" Blood Pressure Phenotypes on Left Ventricular Hypertrophy.

OBJECTIVE: We aimed to evaluate the clinical significance of the "unclassified" blood pressure phenotypes on left ventricular hypertrophy in children. MATERIALS AND METHODS: All children evaluated with ambulatory blood pressure monitoring in the pediatric nephrology department between October 2018 and January 2021 were included in the study. Prehypertension, normotensive, white coat hypertension, masked hypertension, ambulatory hypertension groups and 2 other groups including increased blood pressure load, normal ambulatory blood pressure measurements, but normal (unclassified group 1) or high (unclassified group 2) office blood pressure measurements were defined according to the American Heart Association 2014 statement. Left ventricular mass index, left ventricular mass index/95 percentile values, and left ventricular hypertrophy ratios were compared between the groups separately to establish the influence of the unclassified cases. RESULTS: A total of 497 children were included. There were 52 cases in normotensive, 47 cases in unclassified group 1, 50 cases in masked hypertension, 79 cases in white coat hypertension, 104 cases in unclassified group 2, and 165 cases in the ambulatory hypertension group. Left ventricular mass index/95 percentile and left ventricular hypertrophy in masked hypertension were significantly higher than normotensive but similar between normotensive and unclassified group 1 groups. Left ventricular hypertrophy was significantly higher in the ambulatory hypertension group compared to white coat hypertension, and similar between white coat hypertension and unclassified group 2 groups. CONCLUSION: Independent of age, we have found that interpretation of blood pressure load not only has a limited predictable effect on left ventricular hypertrophy but also causes a large group of patients to be unclassified. Cite this article as: Kasap-Demir B, Basaran C, Demircan T, et al. The effect of "unclassified" blood pressure phenotypes on left ventricular hypertrophy. Turk Arch Pediatr. 2024;59(1):43-48.

Using games to understand the mind.

Board, card or video games have been played by virtually every individual in the world. Games are popular because they are intuitive and fun. These distinctive qualities of games also make them ideal for studying the mind. By being intuitive, games provide a unique vantage point for understanding the inductive biases that support behaviour in more complex, ecological settings than traditional laboratory experiments. By being fun, games allow researchers to study new questions in cognition such as the meaning of 'play' and intrinsic motivation, while also supporting more extensive and diverse data collection by attracting many more participants. We describe the advantages and drawbacks of using games relative to standard laboratory-based experiments and lay out a set of recommendations on how to gain the most from using games to study cognition. We hope this Perspective will lead to a wider use of games as experimental paradigms, elevating the ecological validity, scale and robustness of research on the mind.

Reformulating Reactivity Design for Data-Efficient Machine Learning.

Machine learning (ML) can deliver rapid and accurate reaction barrier predictions for use in rational reactivity design. However, model training requires large data sets of typically thousands or tens of thousands of barriers that are very expensive to obtain computationally or experimentally. Furthermore, bespoke data sets are required for each region of interest in reaction space as models typically struggle to generalize. We have therefore reformulated the ML barrier prediction problem toward a much more data-efficient process: finding a reaction from a prespecified set with a desired target value. Our reformulation enables the rapid selection of reactions with purpose-specific activation barriers, for example, in the design of reactivity and selectivity in synthesis, catalyst design, toxicology, and covalent drug discovery, requiring just tens of accurately measured barriers. Importantly, our reformulation does not require generalization beyond the domain of the data set at hand, and we show excellent results for the highly toxicologically and synthetically relevant data sets of aza-Michael addition and transition-metal-catalyzed dihydrogen activation, typically requiring less than 20 accurately measured density functional theory (DFT) barriers. Even for incomplete data sets of E2 and SN2 reactions, with high numbers of missing barriers (74% and 56% respectively), our chosen ML search method still requires significantly fewer data points than the hundreds or thousands needed for more conventional uses of ML to predict activation barriers. Finally, we include a case study in which we use our process to guide the optimization of the dihydrogen activation catalyst. Our approach was able to identify a reaction within 1 kcal mol-1 of the target barrier by only having to run 12 DFT reaction barrier calculations, which illustrates the usage and real-world applicability of this reformulation for systems of high synthetic importance.

Pulse Wave Analysis in Obese Children with and without Metabolic Syndrome

Objective: To compare pulse wave analysis (PWA) of obese children with and without metabolic syndrome (MS) with healthy, non-obese children and to evaluate the association between PWA findings and additional risk factors present in children with MS and obesity. Methods: From the obese patients examined between June 2019 and June 2021, 41 patients with MS, 36 obese patients without MS, and 34 healthy non-obese children of similar age and gender were evaluated retrospectively. Anthropometric measurements, biochemical evaluation, 24-hour ambulatory blood pressure (BP) measurement (ABPM), left ventricular mass index (LVMI) and PWA measurements were compared. Results: When the three groups were compared, weight standard deviation score (SDS), height SDS and body mass index SDS were all significantly higher in the MS group (p<0.05). The following measurements were significantly higher in both MS and non-MS obese patients compared to the control group: from ABPM measures, the systolic and mean arterial pressure BP SDSs load; from PWA, the night central systolic BP, 24-hour, day and night pulse pressure values and 24-hour, day and night pulse wave velocity (PWV) rates; and from cardiac evaluations, the LVMI and relative wall thickness measurements (all p<0.05). Furthermore, the 24-hour and daytime central systolic (cSBP) and diastolic BP (cDBP) values were significantly different between the three groups, being the highest in the MS group (p<0.05). Conclusion: Obesity causes higher office, ambulatory and central BP, PWV and LVMI. However our results suggest that additional risk factors associated with MS do not contribute to these parameters, except for 24-hour and daytime cSBP and cDBP values.

Evaluation of Pediatric Patients with a Diagnosis of Ureterocele.

Aim: The presence and clinical importance of vesicoureteric reflux in patients with a double collecting system are being questioned. Therefore, the role of voiding cystourethrography in the management of patients with ureterocele is unclear. This study aimed to evaluate patients with a ureterocele in terms of urinary tract infection (UTI) and vesicoureteral reflux (VUR). Material Methods: The cases who were admitted to the Pediatric Nephrology Clinic of Health Sciences University Tepecik Training and Research Hospital between 2012 and 2022 and were diagnosed with ureterocele were evaluated retrospectively. Demographic, clinical, and laboratory data were obtained from file records. Results: All patients diagnosed with ureterocele and voiding cystourethrography (VCUG) were evaluated. A total of 24 (female 13 (54.2%)) children were included. The reasons for admission were antenatal hydronephrosis in 13 (54.2%) patients, UTI in 9 (37.5%) patients, and incidentally diagnosed ureterocele in 2 (8.3%) patients. Urinary tract infection was observed in 20 patients at admission, recurrent UTI in 21 patients at follow-up, preoperative pyelonephritis in 12 patients. VUR was found in 11 patients, and severe VUR (≥stage 3) was found in 9 patients. Ten patients had ipsilateral hydronephrosis, and 14 patients had a double collecting system. The presence of VUR was found to be associated with female gender, UTI at admission, and recurrent UTI at follow-up (p < 0.05). However, there was no difference between groups with or without VUR in terms of ipsilateral hydronephrosis, scar formation, and the need for surgery (p > 0.05). Conclusions: We could not demonstrate any criteria to select patients to receive VCUG; on the other hand, VUR did not cause more kidney damage. Our study supports the need for more scientific data to determine management in patients with ureterocele.