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Gain-of-function RyR1-p.R163C mutation in ryanodine receptors type 1 (RyR1) deregulates Ca2+ signaling and mitochondrial function in skeletal muscle and causes malignant hyperthermia in humans and mice under triggering conditions. We investigated whether T lymphocytes from heterozygous RyR1-p.R163C knock-in mutant mice (HET T cells) display measurable aberrations in resting cytosolic Ca2+ concentration ([Ca2+]i), Ca2+ release from the store, store-operated Ca2+ entry (SOCE), and mitochondrial inner membrane potential (ΔΨm) compared with T lymphocytes from wild-type mice (WT T cells). We explored whether these variables can be used to distinguish between T cells with normal and altered RyR1 genotype. HET and WT T cells were isolated from spleen and lymph nodes and activated in vitro using phytohemagglutinin P. [Ca2+]i and ΔΨm dynamics were examined using Fura 2 and tetramethylrhodamine methyl ester fluorescent dyes, respectively. Activated HET T cells displayed elevated resting [Ca2+]i, diminished responses to Ca2+ mobilization with thapsigargin, and decreased rate of [Ca2+]i elevation in response to SOCE compared with WT T cells. Pretreatment of HET T cells with ryanodine or dantrolene sodium reduced disparities in the resting [Ca2+]i and ability of thapsigargin to mobilize Ca2+ between HET and WT T cells. While SOCE elicited dissipation of the ΔΨm in WT T cells, it produced ΔΨm hyperpolarization in HET T cells. When used as the classification variable, the amplitude of thapsigargin-induced Ca2+ transient showed the best promise in predicting the presence of RyR1-p.R163C mutation. Other significant variables identified by machine learning analysis were the ratio of resting cytosolic Ca2+ level to the amplitude of thapsigargin-induced Ca2+ transient and an integral of changes in ΔΨm in response to SOCE. Our study demonstrated that gain-of-function mutation in RyR1 significantly affects Ca2+ signaling and mitochondrial fiction in T lymphocytes, which suggests that this mutation may cause altered immune responses in its carrier. Our data link the RyR1-p.R163C mutation, which causes inherited skeletal muscle diseases, to deregulation of Ca2+ signaling and mitochondrial function in immune T cells and establish proof-of-principle for in vitro T cell-based diagnostic assay for hereditary RyR1 hyperfunction.

T cell receptor stimulation initiates a cascade of reactions that cause an increase in intracellular calcium (Ca2+) concentration mediated through inositol 1,4,5-trisphosphate (IP3). To understand the basic mechanisms by which the immune response in T cells is activated, it is useful to understand the signaling pathways that contain important targets for drugs in a quantitative fashion. A computational model helps us to understand how the selected elements in the pathways interact with each other, and which component plays the crucial role in systems. We have developed a mathematical model to explore the mechanism for controlling transcription factor activity, which regulates gene expression, by the modulation of calcium signaling triggered during T cell activation. The model simulates the activation and modulation of Ca2+ release-activated Ca2+ (CRAC) channels by mitochondrial dynamics and depletion of endoplasmic reticulum (ER) store, and also includes membrane potential in T-cells. The model simulates the experimental finding that increases in Ca2+ current enhances the activation of transcription factors and the Ca2+ influx through CRAC is also essential for the NFAT and NFκB activation. The model also suggests that plasma membrane Ca2+-ATPase (PMCA) controls a majority of the extrusion of Ca2+ and modulates the activation of CRAC channels. Furthermore, the model simulations explain how the complex interaction of the endoplasmic reticulum, membrane potential, mitochondria, and ion channels such as CRAC channels control T cell activation.

The objective of this study was to assess correlation between dimensions of ball phantom and distortion rate of panoramic radiography in dental cone beam computed tomography (CBCT) system using appropriate standard methods. The results revealed that only two measurement (2.99%) out of 67 measurements exceeded the recommended threshold value for distortion rate. There was no correlation between the ball diameter and the distortion produced. However, a low positive correlation was observed between the distortion rate and the ratio of the horizontal to the vertical diameter of the ball images. Also, the matlab code, presented results which are closer to the acceptable limit than the Romexis software. Patient positioning should be carefully and correctly considered to prevent and to bring the image distortion rate to its barest minimum for proper diagnosis in dental CBCT. For proper diagnosis and treatment planning, this distortion must be accounted for during clinical applications. [ABSTRACT FROM AUTHOR]

The underlying mechanisms of secondary neuronal damage following intracerebellar hemorrhage (ICbH) have not yet been clearly understood. Our previous study reported apoptotic neuronal damage in the perihematomal region (PH) in mice. However, the possible key factors causing secondary neuronal damage in ICbH are not yet known. Therefore, we aimed to study the vital factors in the mediation of secondary neuronal damage following ICbH induced by collagenase type VII (0.4 U/μL of saline) into the cerebellum of mice. The mice were grouped into four groups: (1) control group (n = 12), (2) day-1 group (n = 12), (3) day-3 group (n = 12), and (4) day-7 group (n = 12). All mice underwent behavior assessment following induction of ICbH and were subsequently sacrificed on days 1, 3, and 7. Perihaematoma samples were collected to study morphological changes, immunohistochemistry, nitric oxide (NO) estimation, and oxidative stress markers, respectively. Mouse behavior was disturbed following ICbH on days 3 and 7 compared to the control. In addition, neuronal damage was found in the PH region. Glial fibrillary acidic protein (GFAP) and excitatory amino acid transporter 1 (EAAT1) were highly expressed on day 7, while gamma-aminobutyric acid receptor subunit alpha-1 (GABAAα1)-containing receptor subunit was detected on days 1 and 3. NO increased on day 1 post-induction and decreased on days 3 and 7. The expressions of superoxide dismutase (SOD), catalase (CAT), neuronal nitric oxide synthases (nNOSs), glutathione peroxidase 1, and cyclooxygenase-2 (COX-2) were significantly increased on day 3. Morphological studies of the PH and tissue showed that neuronal damage occurred from day 1 onward and peaked on day 3, associated with alterations in NO, reactive astrocytes (GFAP), glutamate transport regulation (EAAT1), and GABA receptor. Briefly, significant changes in the key markers in the PH regions at different time points are possibly crucial factors facilitating secondary neuronal damage in the PH region. Identifying the time window of these vital changes could help prevent secondary damage and optimize the treatment to occur at proper time points.

A reliable safety climate model is essential for evaluating safety behavior and predicting risks such as accidents or injuries, yet no research has specifically addressed the safety climate in the paper industry, either globally or in Indonesia. Recognized as high-risk due to its reliance on large machinery and hazardous chemicals, the paper industry has been understudied in this context. This research addresses the gap by developing a safety climate model tailored to the Indonesian paper industry, following a rigorous methodology that included a literature review, model design, validation processes, and Goodness-of-Fit testing. The study identified nine dimensions and 36 initial indicators, with strong content validity confirmed through Aiken’s V index, and refined through a survey of 313 employees—including managers, supervisors, and operators—at a paper factory in West Java, Indonesia. Confirmatory factor analysis (CFA) led to the final model, comprising nine dimensions and 32 validated indicators, achieving excellent fit across key criteria. These dimensions include management commitment, safety environment, safety communication, safety involvement, safety rules and procedures, safety training, safety competence, work pressure, and local wisdom. The validated model offers valuable insights into safety practices, providing a practical framework for improving safety performance in the Indonesian paper industry. By fostering a proactive safety culture and addressing sector-specific risks, this model has the potential to significantly reduce workplace accidents and improve overall safety performance, marking an important advancement in industry-specific safety research.

Mutations in the calcium-sensing protein calmodulin (CaM) have been linked to two cardiac arrhythmia diseases, Long QT Syndrome 14 (LQT14) and Catecholaminergic Polymorphic Ventricular Tachycardia Type 4 (CPVT4), with varying degrees of severity. Functional characterization of the CaM mutants most strongly associated with LQT14 show a clear disruption of the calcium-dependent inactivation (CDI) of the L-Type calcium channel (LCC). CPVT4 mutants on the other hand are associated with changes in their affinity to the ryanodine receptor. In clinical studies, some variants have been associated with both CPVT4 and LQT15. This study uses simulations in a model for excitation–contraction coupling in the rat ventricular myocytes to understand how LQT14 variant might give the functional phenotype similar to CPVT4. Changing the CaM-dependent transition rate by a factor of 0.75 corresponding to the D96V variant and by a factor of 0.90 corresponding to the F142L or N98S variants, in a physiologically based stochastic model of the LCC prolonger, the action potential duration changed by a small amount in a cardiac myocyte but did not disrupt CICR at 1, 2, and 4 Hz. Under beta-adrenergic simulation abnormal excitation–contraction coupling was observed above 2 Hz pacing for the mutant CaM. The same conditions applied under beta-adrenergic stimulation led to the rapid onset of arrhythmia in the mutant CaM simulations. Simulations with the LQT14 mutations under the conditions of rapid pacing with beta-adrenergic stimulation drives the cardiac myocyte toward an arrhythmic state known as Ca2+ overload. These simulations provide a mechanistic link to a disease state for LQT14-associated mutations in CaM to yield a CPVT4 phenotype. The results show that small changes to the CaM-regulated inactivation of LCC promote arrhythmia and underscore the significance of CDI in proper heart function. [ABSTRACT FROM AUTHOR]

Integration of buffered Ca2+ diffusion, IP3 diffusion and a realistic inositol 1,4,5-triphosphate (IP3)-induced Ca2+ oscillation model reveals that Ca2+ diffusion and Ca2+ bulk movements do not have any prominent effect on agonist-induced Ca2+ wave trains. The waves are kinetic in nature, with the steady-state IP3 value defining the period of wave trains whose speed and wavelengths depend on the phase differences between oscillators at distinct space points. IP3 diffusion determines the wave gradients of wave trains that include localized Ca2+ secretion and influx cycles.

Electrospinning has become a robust technique for the cost-effective production of fibrous materials. In a conventional electrospinning process, the produced fibers are fabricated by either vertical or horizontal setups, resulting in isotropic non-woven fibers mats. Many researchers have focused on the influence of various electrospinning parameters, solution parameters and ambient parameters. However, until now less attention has been paid on the impact of gravity on fiber and mat morphologies. This article presents a novel approach for altering the morphology of electrospun TiO2/PVP nanofiber mats using a simple concept based on different deposition angles. The electrospinning setups used involved five deposition angles (0°, 45°, 90°, 135°, and 180°), which revealed an effect of gravity on fiber mat morphology and fiber diameter. This work provides new prospects toward the design of electrospun fiber mats and provides us with additional options to achieve optimal results. [ABSTRACT FROM AUTHOR]