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Age-related volumetric differences of hippocampal subfields in the developing brain: A retrospective mri study
No full textResults of studies examining hippocampal subfield development and age-related differences are conflicting. This study aimed to investigate age- and sex-related volumetric differences and asymmetry in hippocampal subfields in childhood and adolescence. In this retrospective study, we included 443 individuals (200 females) with normal radiological anatomy between the ages of 2 and 18 years who had a brain MRI between 2012 and 2023. We obtained absolute and relative volumes of CA1-3, CA4-DG, and subiculum with Kulaga-Yoskovitz segmentation of volBrain HIPS in 3D-T1-weighted MRIs. We compared the volumetric data of developmental periods with SPSS (ver.28). Total hippocampal volume was consistent with quadratic models in females and sigmoid (absolute) and inverse (relative) models in males. CA1-3 showed age-related differences best characterized by sigmoid, CA4-DG by cubic and quadratic, and subiculum by cubic and power models. Total hippocampus and CA1-3 volumes were significantly smaller in the toddler period than in other periods (p 0.05). In absolute volume, hippocampal structures differed between the sexes, but only CA4-DG had sexual dimorphism in relative volume (p right asymmetry, while other hippocampal subfields were lateralized to the right. This study demonstrated that hippocampal subfields exhibited heterogeneity in terms of age-related differences, with the subiculum being more sensitive to age-related factors, and CA4-DG showed a proportional increase with brain development
Reliability of pulmonary function tests in patients with chronic obstructive pulmonary disease
No full textIntroduction: Chronic Obstructive Pulmonary Disease (COPD) is frequently underdiagnosed due to limited use and suboptimal quality of spirometry. Methods: This multicenter, prospective observational study aimed to assess the quality of spirometry tests in COPD patients across six tertiary care centers in Turkey. A total of 560 spirometry tests were independently evaluated by two pulmonologists, and inter-rater reliability was analyzed using Cohen's Kappa. Results: The study included 124 women and 436 men, with a mean age of 65.9 +/- 10.2 years. Spirometry patterns were interpreted as obstructive in 79.1% of tests, restrictive in 5.7%, mixed in 2.7%, normal in 6.7%, inconclusive in 5.5%, and as upper airway obstruction in 0.18% of cases (K=0.890). Routine post-bronchodilator testing was performed in 87.14% of the cases, while 12.85% were post-reversibility tests. Graphical data included volume-time curves (88.5%), flow-volume loops (99.6%), and inspiratory limbs (98.7%). Reference values were predominantly based on ECSC (86.4%), followed by GLI (8.9%) and NHANES (0.25%). Mean spirometric values included FEV1 (% predicted) 57.2%, FVC (% predicted) 72.7%, and FEV1/FVC 61.9%. Cough in the first second of FVC was observed in 17 (3%) (K=0.677), variable or insufficient effort 13.4% (K=0.563), mouth leak 1.8% (K=0.305), mouthpiece obstruction 0.5% (K=0.332), rapid expiration 1.8% (K=0.354), increased concavity 83% (K=0.683), and small airway obstruction 87% (K=0.709) were reported by interpreters. Conclusion: Spirometry reports frequently lack key information such as preliminary diagnoses, test indication, technician, and device details. ECSC is the most commonly used reference. Rates of inconclusive and erroneous tests-due to variable or insufficient effort, mouth leak, mouthpiece obstruction, and rapid expiration-are low
Clinical practice of the endothelial activation and stress index and its modified versions in multiple myeloma and the effects on prognosis
No full textObjective: Here, we aimed to evaluate the prognostic values of the endothelial activation and stress index (EASIX) and its derivatives, modified EASIX (mEASIX) and simplified EASIX (sEASIX), in patients with multiple myeloma (MM). Methods: The data of 134 newly diagnosed MM patients between January 2020 and December 2024 were retrospectively analyzed. Patients were divided into groups based on EASIX and its derivatives, and the outcomes of survival rates in groups were compared. Optimal cut-off points were determined using the receiver-operating characteristic analysis, and mortality predictive values of the scores were investigated. The independent prognostic factors were evaluated through univariate and multivariate Cox regression analyses. Results: The optimal cut-off point for EASIX was detected as >1.03, and survival times were significantly shorter in patients with higher EASIX scores (p 26.5, showing higher specificity (area under curve (AUC) = 0.663; p = 0.003). The sEASIX score predicted lower mortality (AUC = 0.586; p = 0.123). In multivariate analysis, high EASIX scores, not performing autologous stem cell transplantation, and not receiving immunomodulatory therapy were identified as independent negative prognostic factors for survival. Conclusion: EASIX, especially mEASIX, is a valuable prognostic tool for predicting survival in MM patients. EASIX can be easily integrated into clinical practice due to its simple computability and reliance on commonly used laboratory parameters. However, larger prospective studies are needed to determine how these scores can be integrated with traditional prognostic systems such as the International Staging System (ISS) and Revised-ISS
Polyurethane peripheral venous catheter as a permanent microvascular graft in a rat model: Potential application as an artificial vascular graft in digital replantation
No full textBackground: Restoring vascular continuity is crucial in digital replantation when direct anastomosis is not possible. Although autologous vein grafts are standard, they pose technical challenges and donor-site morbidity. This study evaluated the short-term patency and histopathological response of inexpensive and readily available polyurethane peripheral venous catheters (PPVC) grafts in a rat femoral artery model. Methods: Twenty male Wistar Albino rats were randomly divided into 2 groups: PPVC graft (n = 10) and autologous vein graft (n = 10). A 5-mm femoral artery defect was repaired with either a 26G PPVC or a contralateral femoral vein segment. After 3 weeks, vascular patency was assessed by ultrasonography and histopathology. Thrombus formation, fibrosis, neovascularization, calcification, and inflammatory infiltration were semiquantitatively scored (0-3). Statistical analysis was performed using the Mann-Whitney U and Fisher exact tests, with P < 0.05 considered significant. Results: Compared with the autograft group, the PPVC group demonstrated significantly higher scores for thrombus formation (P < 0.001), fibrosis (P = 0.002), neovascularization (P = 0.001), and inflammatory infiltration (P = 0.003). Calcification was not observed in either group. Severe thrombus formation occurred in one rat in the autograft group and 3 in the PPVC group. Despite these findings, no clinical signs of ischemia, including discoloration or gait impairment, were observed during follow-up. Conclusion: PPVC grafts are technically feasible and show partial biological integration within 3 weeks. However, higher thrombosis, fibrosis, and inflammation indicate limited short-term patency compared with autologous grafts. Further studies with longer follow-up and surface modifications are needed
Step-ladder bioprinting to align collagen fibers for anisotropic tissue fabrication
No full textAligned collagen microstructure is essential for the mechanical and biological function of anisotropic tissues. However, conventional engineering methods often fail to achieve consistent and tunable fiber alignment within complex geometries. In this study, we developed a step-ladder printing (SLP) approach by incorporating successive segments of channels of variable widths into a custom barrel design, combining controlled extensional flows with 3D bioprinting to enhance collagen fiber alignment. The results revealed that constructs 3D-printed via SLP demonstrated improved anisotropy of collagen fibers and narrower fiber angle distributions compared to both extrusion-based bioprinting with a conventional straight nozzle and drop casting methods. Furthermore, SLP effectively guided the directionality of seeded cells, aligning them consistently with underlying collagen fibers. To exemplify the utility of SLP, we built corneal constructs, achieving high transparency and shape fidelity, and articular cartilage constructs, showing mechanical properties within the range of native tissue and supported extracellular matrix production. These results suggest that the SLP approach offers a strategy for fabricating complex anisotropic tissues with integrated fiber alignment and cellular guidance.Materials Research Institute Interdisciplinary Seed Gran
Eco-anxiety profiles, religiosity, and sustainable nutrition in turkish adults: A latent profile and network analysis
No full textBackground: Eco-anxiety is increasingly viewed as a multidimensional response to the climate crisis, but its links with religiosity and sustainable nutrition behaviors in highly religious settings are unclear. We identified eco-anxiety profiles in Turkish adults; compared religiosity, sustainable nutrition behaviors, and body mass index (BMI) across profiles; and examined the multivariate network connecting these domains. Methods: This cross-sectional online survey in T & uuml;rkiye included 1105 adults (69.3% women; age 25.8 +/- 8.4 years; BMI 23.5 +/- 4.5 kg/m(2)). Participants completed the Eco-anxiety Scale, Duke University Religion Index, and Behaviors Scale Toward Sustainable Nutrition. Latent profile analysis used four eco-anxiety subscales. Between-profile differences were tested using canonical discriminant analysis and Kruskal-Wallis tests. A Gaussian graphical model estimated with EBICglasso assessed network connectivity. Results: Four profiles emerged: High (11.9%), Moderate (54.8%), Affective-dominant (8.3%), and Low (24.9%). Compared with the Low profile, the High profile showed higher sustainable nutrition scores for food preference, seasonal/local nutrition, and food purchasing (all p < 0.05); however, effect sizes were small (eta(2)(H) = 0.008-0.014), indicating modest practical differences. BMI did not differ across profiles (p = 0.211). In the network, seasonal/local nutrition had the highest strength centrality, whereas BMI was peripheral and weakly connected to other nodes. Conclusions: Eco-anxiety was heterogeneous and showed modest associations with sustainable nutrition behaviors at the group level, without differences in BMI. These preliminary findings suggest that eco-anxiety may co-occur with more sustainable food-related choices, generating hypotheses for future replication.Acıbadem Mehmet Ali Aydınlar Üniversites
A novel hyperbolic tangent-based pid controller tuned by the artificial lemming algorithm for nonlinear steam condenser pressure control
No full textPrecise pressure regulation in nonlinear shell-and-tube steam condensers is essential for maintaining thermal efficiency and operational safety in power generation plants; however, conventional proportional-integral (PI) and proportional-integral-derivative (PID) controllers struggle with nonlinear dynamics, leading to overshoot, slower settling, and reduced robustness. In this regard, a novel hyperbolic tangent-based PID (tanh-PID) controller is developed in this study to introduce smooth nonlinear gain modulation, enabling enhanced damping behavior and improved transient shaping. The recently introduced artificial lemming algorithm (ALA) is employed to optimally tune the proposed controller for integral of time-weighted absolute error minimization. Extensive simulation studies are performed using a comprehensive nonlinear condenser model incorporating steam-air interactions and hot-well dynamics. The proposed strategy is benchmarked against four competitive optimization algorithms (coati optimization algorithm, dandelion optimizer, success-history based adaptive differential evolution with linear population size reduction, and adaptive artificial electric field algorithm) and compared with state-of-the-art PI and fractional-order PID (FOPID) controllers reported in the literature. The ALA-tuned tanh-PID achieves the lowest integral of time-weighted absolute error (2.1189), fastest rise time (0.5960 s), minimal settling time (12.4799 s) and overshoot (5.8056%), along with near-zero steady-state error (4.0776 x 10(-)4%), outperforming all compared methods in both transient response and steady-state accuracy. Robustness analyses further confirm superior disturbance rejection and reliable reference tracking under dynamic uncertainties. These results demonstrate that the proposed methodology offers an efficient, low-complexity, and high-performance control solution suitable for real-time deployment in industrial steam condenser systems
GNE mutation-related congenital thrombocytopenia in 2 siblings: Case reports and literature review
No full textBackground: GNE mutations are rare pathologic conditions that can cause severe thrombocytopenia and bleeding tendency from the neonatal period. The clinical presentation of patients with GNE mutations varies from mild skin and mucosal bleeding to life-threatening bleeding. Case Presentation: This study reported two siblings with hereditary thrombocytopenia. The 2 patients exhibited severe thrombocytopenia (platelet [PLT] count: A [p.Gly559Arg]) was detected in GNE. One sibling was unresponsive to the platelet receptor agonists eltrombopag and romiplostim. Meanwhile, the other sibling was unresponsive to eltrombopag but was responsive to romiplostim. Conclusion: The first-line treatment of patients with GNE mutations is PLT transfusion. However, the management of patients with severe thrombocytopenia and frequent bleeding is challenging. Thrombopoietin receptor agonists are administered to these patients to mitigate the risk of alloimmunization and PLT transfusion refractoriness. However, the observed responses may differ even in siblings carrying the same mutation. This differential response may be related to bone marrow megakaryocyte reserves and hepatocyte Aswell-Morell receptor levels
Analysis of optical soliton parameters and exact solutions in a generalized third-order nonlinear schrödinger equation
No full textIn this paper, we explore optical solitons in a generalized third-order nonlinear Schr & ouml;dinger equation (GNLSE) for ultrashort pulse propagation in nonlinear optical fibers. Using the collective variable (CV) method, we derive a system of ordinary differential equations that describes key soliton parameters, such as amplitude, width, chirp, and frequency. The numerical solutions obtained using the fourth-order Runge-Kutta algorithm show periodic oscillations of the aforementioned parameters. Another key result of the study is the discovery of bright soliton solutions using the semi-inverse method with fractal derivatives. We also demonstrate the effects of fractal parameters on the soliton solution with graphical simulations. Fractal dimensions (Psi < 1) generate pulse irregularities that match experimental observations. The results clarify the interaction of higher-order effects, nonlinearity, and dispersion. In addition, the study's findings highlight the importance of two methods used to improve data transmission in optical fibers and relate the theoretical analysis to potential real-world applications
