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OBJECTIVE: Right ventricular (RV) overload findings affect the risk classification and treatment approach in acute pulmonary embolism (APE). Recently, it was reported that a new electrocardiography (ECG) parameter, terminal D1S + D3R (T-D1S + D3R) pattern, supported the diagnosis of APE. We aim to search the relationship between T-D1S + D3R pattern and right ventricular dilatation (RVD) in APE. METHODS: This single-centre, retrospective study was designed with patients aged > 18 years. We screened 267 patients who underwent transthoracic echocardiography (TTE) because of confirmed APE in our emergency department. This study included 72 patients with RVD and 139 patients without RVD [male 41.7%, median age 73,0 (20.8) years; 49.6% male, median age 64,0 (24.0) years]. We compared T-D1S + D3R between RVD (+) and RVD (-) groups. RESULTS: We determined that RVD (+) group had more patients with the T-D1S + D3R parameter than RVD (-) group [51 (70.8%) vs. 25 (18.0%), p < 0.001]. In the univariate logistic regression analyses S1Q3T3, (in)complete right bundle branch block (RBBB), T-D1S + D3R, D3-V1 T wave inversion (TWI), V1-3/4 TWI, V1-3/4 ST-segment elevation, and frontal QRS-T [f(QRS-T)] angle predicted RVD, while T-D1S + D3R, V1-3/4 ST-segment elevation, and f(QRS-T) angle remained independent predictors of RVD in patients with APE. CONCLUSIONS: T-D1S + D3R, a new ECG parameter, was an independent predictor of RVD in patients with APE.

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The atrioventricular node (AVN) is a key component of the cardiac conduction system and takes over pacemaking of the ventricles if the sinoatrial node fails. IP3 (inositol 1,4,5 trisphosphate) can modulate excitability of myocytes from other regions of the heart, but it is not known whether IP3 receptor (IP3-R) activation modulates AVN cell pacemaking. Consequently, this study investigated effects of IP3 on spontaneous action potentials (APs) from AVN cells isolated from rabbit hearts. Immunohistochemistry and confocal imaging demonstrated the presence of IP3-R2 in isolated AVN cells, with partial overlap with RyR2 ryanodine receptors seen in co-labelling experiments. In whole-cell recordings at physiological temperature, application of 10 µM membrane-permeant Bt3-(1,4,5)IP3-AM accelerated spontaneous AP rate and increased diastolic depolarization rate, without direct effects on ICa,L, IKr, If or INCX. By contrast, application via the patch pipette of 5 µM of the IP3-R inhibitor xestospongin C led to a slowing in spontaneous AP rate and prevented 10 µM Bt3-(1,4,5)IP3-AM application from increasing the AP rate. UV excitation of AVN cells loaded with caged-IP3 led to an acceleration in AP rate, the magnitude of which increased with the extent of UV excitation. 2-APB slowed spontaneous AP rate, consistent with a role for constitutive IP3-R activity; however, it was also found to inhibit ICa,L and IKr, confounding its use for studying IP3-R. Under AP voltage clamp, UV excitation of AVN cells loaded with caged IP3 activated an inward current during diastolic depolarization. Collectively, these results demonstrate that IP3 can modulate AVN cell pacemaking rate.

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The molecular mechanisms leading to saliva secretion are largely established, but factors that underlie secretory hypofunction, specifically related to the autoimmune disease Sjögren's syndrome (SS) are not fully understood. A major conundrum is the lack of association between the severity of salivary gland immune cell infiltration and glandular hypofunction. SS-like disease was induced by treatment with DMXAA, a small molecule agonist of murine STING. We have previously shown that the extent of salivary secretion is correlated with the magnitude of intracellular Ca2+ signals (Takano et al., 2021). Contrary to our expectations, despite a significant reduction in fluid secretion, neural stimulation resulted in enhanced Ca2+ signals with altered spatiotemporal characteristics in vivo. Muscarinic stimulation resulted in reduced activation of the Ca2+-activated Cl- channel, TMEM16a, although there were no changes in channel abundance or absolute sensitivity to Ca2+. Super-resolution microscopy revealed a disruption in the colocalization of Inositol 1,4,5-trisphosphate receptor Ca2+ release channels with TMEM16a, and channel activation was reduced when intracellular Ca2+ buffering was increased. These data indicate altered local peripheral coupling between the channels. Appropriate Ca2+ signaling is also pivotal for mitochondrial morphology and bioenergetics. Disrupted mitochondrial morphology and reduced oxygen consumption rate were observed in DMXAA-treated animals. In summary, early in SS disease, dysregulated Ca2+ signals lead to decreased fluid secretion and disrupted mitochondrial function contributing to salivary gland hypofunction.

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Many reproductive proteins show signatures of rapid evolution through sequence divergence and duplication. These features of reproductive genes may complicate the detection of orthologs across taxa, making it difficult to connect studies in model systems to human biology. In mice, ZP3r/sp56 is a binding partner to the egg coat protein ZP3 and may mediate induction of the acrosome reaction, a crucial step in fertilization. In rodents, ZP3r, as a member of the Regulators of Complement Activation cluster, is surrounded by paralogs, some of which have been shown to be evolving under positive selection. Although primate egg coats also contain ZP3, sequence divergence paired with paralogous relationships with neighboring genes has complicated the accurate identification of the human ZP3r ortholog. Here, we phylogenetically and syntenically resolve that the human ortholog of ZP3r is the pseudogene C4BPAP1. We investigate the evolution of this gene within primates. We observe independent pseudogenization events of ZP3r in all Apes with the exception of Orangutans, and independent pseudogenization events in many monkey species. ZP3r in both primates that retain ZP3r and in rodents contains positively selected sites. We hypothesize that redundant mechanisms mediate ZP3 recognition in mammals and ZP3r's relative importance to ZP recognition varies across species.

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BACKGROUND: Right ventricular systolic dysfunction is associated with poor prognosis and increased mortality rates. Our objective was to investigate ECG changes in patients with this condition, focusing on the right-sided precordial leads. METHODS: In this cross-sectional study, 60 patients with right ventricular dysfunction were included from April 2020 to April 2021. Cardiac structure and function were assessed using 2D transthoracic echocardiography. Standard 12-lead electrocardiograms and right-sided precordial ECGs (V3R-V4R) were obtained and analyzed for QRS complex configuration, ST-segment elevation, and T-wave morphology. RESULTS: In our study, the majority were male (70.0%) with a mean age of 58.76 years. The most common initial diagnoses were pulmonary thromboembolism (43.3%), chronic obstructive pulmonary disease (26.7%), and pulmonary hypertension (25.0%). The predominant ECG finding in the right-sided precordial leads (V3R, V4R) was a deep negative T wave (90.0%). Patients with severe right ventricular systolic dysfunction often exhibited a qR pattern (41.2%), whereas those with nonsevere dysfunction showed rS and QS patterns (55.8%). Approximately 41.0% of severe RV dysfunction cases had ST segment depression in the right-sided precordial leads, and 28.0% of patients displayed signs of right atrial abnormality. CONCLUSION: The study found that qR, rS, and QS patterns were more prevalent in V3R and V4R leads among patients with severe and nonsevere right ventricular systolic dysfunction. The most common ECG feature observed was deep T-wave inversion in these leads. The study recommends using right-sided precordial leads in all patients with RV systolic dysfunction for early detection and risk stratification.

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OBJECTIVES: To present the clinical journey and management of a 15-year-old female with SHORT syndrome, highlighting the diagnostic challenges and the novel genetic mutation identified. CASE PRESENTATION: A 15-year-old Filipino female was initially seen in a dermatology clinic at 9 years old for axillary skin darkening, indicative of acanthosis nigricans. Early evaluations revealed elevated blood glucose levels, resulting in a pediatric diabetes diagnosis without the usual hyperglycemic symptoms. Her medical history was notable for premature birth, intrauterine growth restriction, a cardiac murmur from patent ductus arteriosus and a bicuspid aortic valve, delayed teething, and distinct dysmorphic features. Genetic testing identified a novel PIK3R1 gene mutation. Treatment with Metformin significantly improved her glycemic control and lipid profiles. The patient also displayed delayed puberty and polycystic ovary syndrome-like symptoms, but growth hormone deficiency was excluded. Endocrine evaluation for her short stature and lipodystrophy confirmed the presence of the PIK3R1 mutation. CONCLUSIONS: This case highlights the importance of thorough endocrine and genetic evaluations in patients with complex clinical presentations like SHORT syndrome. The identification of a novel PIK3R1 gene mutation expands the understanding of the genetic basis of this syndrome and underscores the need for individualized treatment approaches.

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This study investigates the postbiotic potential of extracellular products (ECPs) from Bacillus pumilus strains cultivated on microalgae-supplemented media. We assessed enzymatic and antimicrobial activities to select ECPs that enhance the digestive processes in gilthead seabream. Additionally, we explored the in vitro enzymatic capacity of the chosen postbiotics to hydrolyze macromolecules in microalgae. Finally, a feeding trial was conducted to determine the in vivo effects of the ECPs on Sparus aurata. In vitro enzymatic assays demonstrated diverse hydrolytic capacities among ECPs. All conditions exhibited antimicrobial activity against Photobacterium damselae subsp. piscicida, with variation in inhibitory effects against Vibrio harveyi and Tenacibaculum maritimum. Furthermore, in vitro assays revealed differences in protein hydrolysis and soluble protein concentration, influencing amino acid and reducing sugar release from microalgal biomass. These analyses facilitated a selection to test ECPs in vivo. Lastly, the in vivo experiment revealed no differences in the growth performance, nutrient utilization, and general metabolism of S. aurata fed the experimental diets. Dietary inclusion of postbiotics increased the activity of key digestive enzymes in fish compared to the control group, and particularly, values increased significantly when the fish were fed with the ECP-nanoparticulate-supplemented diet. In conclusion, the inclusion of microalgae in the culture media significantly influences the activity of extracellular products from B. pumilus strains, as evidenced in both in vitro and in vivo assays.

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Physiology is a scientific discipline of how people's and animals' bodies function that requires traditionally suitable experimental models that often rely on animals. However, at the end of the 50th of the last century, researchers themselves addressed concerns about the use of animals for biomedical science and physiology in particular. At that time, the so-called 3R strategy was implicated where the three "R" stand for replacement, reduction, and refinement. When addressing these concerns, researchers nevertheless realized that a critical dispute about experimental models in the light of the 3R initiative may require further attention to other points such as robustness, registration, reporting, reproducibility, and rigor of the work. The question that has to be addressed now is first whether the use of animals in physiology changed in the post-3R period, whether it led to a replacement, reduction, or refinement of animal handling, and most importantly, how this affected the scientific progress in (patho)physiology. In order to address open questions concerning the relationship between the use of animals and physiological research, complete volumes of the Pflügers Archiv - European Journal of Physiology were analyzed every 10 years starting in 1950 and ending in 2020 and compared to volumes of the Journal of Physiology. It analyzed how scientists organize their projects published in the journal and what kind of models they used. The results show that physiological science has dramatically changed in the last 70 years. Replacement, reduction, and refinement were achieved to a certain level. However, during the last years, no further achievement could be seen. It seems that a certain level of animal testing is required for biomedical science and physiology in particular. Physiological studies in the present time are dominated by investigation of the physiological function of small rodents mainly mice and rats with only a few exceptions. The analysis also shows that in the future, researchers must have a critical look at further requirements of their research such as data robustness, improvement of reproducibility of data, and generation of rigor data as a prerequisite to improve our physiological view on life.

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Compelling evidence has been presented in favor of herpes simplex virus type 1 (HSV1) being one of the causative agents of Alzheimer's disease (AD). The success of HSV1 as a pathogen relates to its sophisticated strategies to evade host immunosurveillance. One strategy involves encoding a decoy Fcγ receptor (FcγR) that thwarts the Fcγ-mediated effector functions, such as antibody-dependent cellular cytotoxicity (ADCC), a potent host immunosurveillance mechanism against virally infected cells. The decoy FcγR binds to antibodies of all IgG subclasses, except IgG3; therefore, IgG3 would be expected to play an important role in viral clearance by neutralization and ADCC, and thus contribute to protection from HSV1-spurred diseases. Previous studies have shown significant association between anti-HSV1 IgG3 antibodies and cortical thinning of the areas of the brain typically altered in AD and also targeted by HSV1. The aim of the present investigation was to determine whether GM (γ marker) 5 and GM 21 allotypes, hereditary allelic determinants expressed on IgG3, together with brain biomarkers of neural integrity, contributed to neurodegeneration-as measured by mini-mental state examination (MMSE) score-in patients with AD. Multiple regression analyses showed that the homozygous GM 5/5 genotype, preserved right hippocampus, and right insula thickness were associated with higher MMSE scores (p < 0.001), whereas the opposite pattern and GM 5/21 genotype were associated with worse clinical profiles. Influence of GM 5/21-expressing IgG3 antibodies on the ADCC of HSV1-infected neurons could, at least partially, explain these results.

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PURPOSE: Chronic Obstructive Pulmonary Disease (COPD) is regarded as an accelerated aging disease. Aging-related genes in COPD are still poorly understood. METHOD: Data set GSE76925 was obtained from the Gene Expression Omnibus (GEO) database. The "limma" package identified the differentially expressed genes. The weighted gene co-expression network analysis (WGCNA) constructes co-expression modules and detect COPD-related modules. The least absolute shrinkage and selection operator (LASSO) and the support vector machine recursive feature elimination (SVM-RFE) algorithms were chosen to identify the hub genes and the diagnostic ability. Three external datasets were used to identify differences in the expression of hub genes. Real-time reverse transcription polymerase chain reaction (RT-qPCR) was used to verify the expression of hub genes. RESULT: We identified 15 differentially expressed genes associated with aging (ARDEGs). The SVM-RFE and LASSO algorithms pinpointed four potential diagnostic biomarkers. Analysis of external datasets confirmed significant differences in PIK3R1 expression. RT-qPCR results indicated decreased expression of hub genes. The ROC curve demonstrated that PIK3R1 exhibited strong diagnostic capability for COPD. CONCLUSION: We identified 15 differentially expressed genes associated with aging. Among them, PIK3R1 showed differences in external data sets and RT-qPCR results. Therefore, PIK3R1 may play an essential role in regulating aging involved in COPD.

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While neurosurgical interventions are frequently used in laboratory mice, refinement efforts to optimize analgesic management based on multimodal approaches appear to be rather limited. Therefore, we compared the efficacy and tolerability of combinations of the non-steroidal anti-inflammatory drug carprofen, a sustained-release formulation of the opioid buprenorphine, and the local anesthetic bupivacaine with carprofen monotherapy. Female and male C57BL/6J mice were subjected to isoflurane anesthesia and an intracranial electrode implant procedure. Given the multidimensional nature of postsurgical pain and distress, various physiological, behavioral, and biochemical parameters were applied for their assessment. The analysis revealed alterations in Neuro scores, home cage locomotion, body weight, nest building, mouse grimace scales, and fecal corticosterone metabolites. A composite measure scheme allowed the allocation of individual mice to severity classes. The comparison between groups failed to indicate the superiority of multimodal regimens over high-dose NSAID monotherapy. In conclusion, our findings confirmed the informative value of various parameters for assessment of pain and distress following neurosurgical procedures in mice. While all drug regimens were well tolerated in control mice, our data suggest that the total drug load should be carefully considered for perioperative management. Future studies would be of interest to assess potential synergies of drug combinations with lower doses of carprofen.

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The present study shows that animals with experimental autoimmune encephalomyelitis (EAE) exhibit olfactory dysfunction and impaired general cognitive abilities, as well as anxiety-like behavior. Olfactory dysfunction occurs on average at 2 dpi, well before the onset of the first motor signs of EAE (8-10 dpi). After the initial olfactory dysfunction, the EAE animals show a fluctuation in olfactory performance that resembles the relapsing-remitting course of human MS. The study also shows severe neuroinflammation in the olfactory bulb (OB), with numerous infiltrated CD4+ T cells and peripheral macrophages in the superficial OB layers, marked microgliosis, and massive induction of TNF-α, IL-1ß, and IL-6. Reduced tyrosine hydroxylase activity in the glomerular layer, pronounced granule cell atrophy, and reduced numbers of type B neuroblasts in the rostral migratory stream also indicate altered plasticity of the neuronal network in the OB. Considering the exceptionally high purinome expression in the OB, the possible involvement of purinergic signaling was also investigated. The study shows that macrophages infiltrating the OB overexpress A3R, while highly reactive microglia overexpress the adenosine-producing enzyme eN/CD73 as well as A2BR, A3R, and P2X4R. Given the simultaneous induction of complement component C3, the results suggest that the microglial cells develop a functional phenotype of phagocytizing microglia. The study also demonstrates transcriptional and translational upregulation of A1R in mitral and tufted cells, which likely influence resting network activity in OB and likely contribute to olfactory dysfunction in EAE. Overall, our study shows that olfactory dysfunction and altered social and cognitive behavior in EAE are associated with increased adenosine signaling via A1R, A2BR, and A3R.

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Sacrificial dilemmas such as the trolley problem play an important role in experimental philosophy (x-phi). But it is increasingly argued that, since we are not likely to encounter runaway trolleys in our daily life, the usefulness of such thought experiments for understanding moral judgments in more ecologically valid contexts may be limited. However, similar sacrificial dilemmas are experienced in real life by animal research decision makers. As part of their job, they must make decisions about the suffering, and often the death, of many non-human animals. For this reason, a context-specific investigation of so-called "3R dilemmas" (i.e., dilemmas where there is a conflict between the principles of replacement, reduction, and refinement of the use of animals in research) is essential to improve the situation of both non-human animals and human stakeholders. An approach well suited for such investigation is experimental philosophical bioethics ("bioxphi"), which draws on methods similar to x-phi to probe more realistic, practical scenarios with an eye to informing normative debates and ethical policy. In this article, we argue for a need to investigate 3R dilemmas among professional decision-makers using the tools of bioxphi. In a first step, we define 3R dilemmas and discuss previous investigations of professionals' attitudes in such cases. In a second step, we show how bioxphi is a promising method to investigate the whys and hows of professional decision-making in 3R dilemmas. In a last step, we provide a bioxphi template for 3R dilemmas, give recommendations on its use, explore the normative relevance of data collected by such means, and discuss important limitations.

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The coordination of food intake, energy storage, and expenditure involves complex interactions between hypothalamic neurons and peripheral tissues including pancreatic islets, adipocytes, muscle, and liver. Previous research shows that deficiency of the transcription factor Alx3 alters pancreatic islet-dependent glucose homeostasis. In this study we carried out a comprehensive assessment of metabolic alterations in Alx3 deficiency. We report that Alx3-deficient mice exhibit decreased food intake without changes in body weight, along with reduced energy expenditure and altered respiratory exchange ratio. Magnetic resonance imaging reveals increased adiposity and decreased muscle mass, which was associated with markers of motor and sympathetic denervation. By contrast, Alx3-deficient mice on a high-fat diet show attenuated weight gain and improved insulin sensitivity, compared to control mice. Gene expression analysis demonstrates altered lipogenic and lipolytic gene profiles. In wild type mice Alx3 is expressed in hypothalamic arcuate nucleus neurons, but not in major peripheral metabolic organs. Functional diffusion-weighted magnetic resonance imaging reveals selective hypothalamic responses to fasting in the arcuate nucleus of Alx3-deficient mice. Additionally, altered expression of proopiomelanocortin and melanocortin-3 receptor mRNA in the hypothalamus suggests impaired regulation of feeding behavior. This study highlights the crucial role for Alx3 in governing food intake, energy homeostasis, and metabolic nutrient partitioning, thereby influencing body mass composition.

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The precipitation behavior of Cu-bearing ultra-low carbon steel after step quenching and tempering at 923 K for 0.5-2.5 h was investigated. The size, quantity, and characteristic distribution of nano-precipitates were analyzed using transmission electron microscopy, and the microstructure of B2 (an ordered structure belonging to the body-centered cubic structure), 9R (a special triclinic lattice that has characteristics of rhombohedral structure), 3R (a special triclinic lattice like 9R), and FCT (face-centered tetragonal lattices) were accurately determined. The relationship between nano-precipitates and mechanical properties under different heat treatment processes was obtained, revealing that nano-precipitates effectively enhanced the yield strength of Cu-bearing ultra-low carbon steel. There were two forms of crystal structure evolution sequence of precipitation: B2→multi twin 9R→detwined 9R→FCT→FCC and B2→multi-twin 9R→detwinned 9R→3R→FCT→FCC. The morphology of the precipitated particles during the growth process changed from spherical to ellipsoidal and finally to rod-shaped. It was proven that a stable 3R structure existed due to the coexistence of 9R, 3R, and FCT structures in the same precipitate particle.

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PT1 peptide isolated from the venom of spider Geolycosa sp. is a modulator of P2X3 receptors that play a role in the development of inflammation and the transmission of pain impulses. The anti-inflammatory and analgesic efficacy of the PT1 peptide was studied in a model of complete Freund's adjuvant-induced paw inflammation in CD-1 mice. The analgesic activity of PT1 peptide was maximum after intramuscular injection at a dose of 0.01 mg/kg, which surpassed the analgesic effect of diclofenac at a dose of 1 mg/kg. The anti-inflammatory activity was maximum after intramuscular injection at a dose of 0.0001 mg/kg; a decrease in paw thickness was observed as soon as 2 h after the administration of the PT1 peptide against the background of inflammation development. All tested doses of PT1 peptide showed high anti-inflammatory activity 4 and 24 h after administration. PT1 peptide at a dose of 0.01 mg/kg when injected intramuscularly simultaneously produced high anti-inflammatory and analgesic effects compared to other doses of the peptide. Increasing the dose of PT1 peptide led to a gradual decrease in its analgesic and anti-inflammatory activity; increasing the dose of intramuscular injection to 0.1 and 1 mg/kg is inappropriate.

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BACKGROUND: Numerous neurological diseases involving neuroinflammation, particularly microglia, contribute to neuronal death. Ferroptosis is implicated in various diseases characterized by neuronal injury. Studies showed that nicotinamide mononucleotide (NMN) inhibits both neuroinflammation and ferroptosis. However, the mechanisms of NMN in both ferroptosis and neuroinflammation remain unclear. We aimed to explore the effects of NMN on neuroinflammation and the susceptibility of microglia to ferroptosis. METHODS: Ferroptosis markers in macroglia exposed to lipopolysaccharides (LPS) were analyzed using CCK8, flow cytometry, ELISA, and quantitative RT-PCR. The effects of NMN on LPS-induced ferroptosis in microglia were evaluated through flow cytometry, western blot, and immunofluorescence staining. RT-PCR analysis assessed the inflammatory cytokine production of microglia subjected to Ferrostatin-1-regulated ferroptosis. RNA sequencing elucidated the underlying mechanism of NMN-involved microglia ferroptosis under LPS induction. In BV2 microglia, an inhibitor of GPX4, RSL3, was employed to suppress GPX4 expression. Intracerebroventricular injection of LPS was performed to evaluate neuroinflammation and microglia activation in vivo. RESULTS: NMN effectively rescued LPS-induced ferroptosis and improved cell viability in microglia. Co-administration of NMN and ferrostatin-1 significantly reduced proinflammatory cytokine production in microglia following the introduction of LPS stimuli. Mechanistically, NMN facilitated glutathione (GSH) production, and enhanced resistance to lipid peroxidation occurred in a manner dependent on GPX4, repressing cytokine transcription and protecting cells from ferroptosis. RNA sequencing elucidated the underlying mechanism of NMN-associated microglia ferroptosis under LPS induction. Furthermore, simultaneous injection of NMN ameliorated LPS-induced ferroptosis and neuroinflammation in mouse brains. The data from the present study indicated that NMN enhances GPX4-mediated ferroptosis defense against LPS-induced ferroptosis in microglia by recruiting GSH, thereby inhibiting neuroinflammation. CONCLUSION: Therapeutic approaches to effectively target ferroptosis in diseases using NMN, consideration should be given to both its anti-ferroptosis and anti-inflammatory effects to attain optimal outcomes, presenting promising strategies for treating neuroinflammation-related diseases or disorders.

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In intravenous immunoglobulins (IVIG), and some other immunoglobulin products, protein particles have been implicated in adverse events. Role and mechanisms of immunoglobulin particles in vascular adverse effects of blood components and manufactured biologics have not been elucidated. We have developed a model of spherical silica microparticles (SiMPs) of distinct sizes 200-2000 nm coated with different IVIG- or albumin (HSA)-coronas and investigated their effects on cultured human umbilical vein endothelial cells (HUVEC). IVIG products (1-20 mg/mL), bare SiMPs or SiMPs with IVIG-corona, did not display significant toxicity to unstimulated HUVEC. In contrast, in TNFα-stimulated HUVEC, IVIG-SiMPs induced decrease of HUVEC viability compared to HSA-SiMPs, while no toxicity of soluble IVIG was observed. 200 nm IVIG-SiMPs after 24 h treatment further increased ICAM1 (intercellular adhesion molecule 1) and tissue factor surface expression, apoptosis, mammalian target of rapamacin (mTOR)-dependent activation of autophagy, and release of extracellular vesicles, positive for mitophagy markers. Toxic effects of IVIG-SiMPs were most prominent for 200 nm SiMPs and decreased with larger SiMP size. Using blocking antibodies, toxicity of IVIG-SiMPs was found dependent on FcγRII receptor expression on HUVEC, which increased after TNFα-stimulation. Similar results were observed with different IVIG products and research grade IgG preparations. In conclusion, submicron particles with immunoglobulin corona induced size-dependent toxicity in TNFα-stimulated HUVEC via FcγRII receptors, associated with apoptosis and mTOR-dependent activation of autophagy. Testing of IVIG toxicity in endothelial cells prestimulated with proinflammatory cytokines is relevant to clinical conditions. Our results warrant further studies on endothelial toxicity of sub-visible immunoglobulin particles.

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Phosphoinositide 3-kinase (PI3K) is responsible for phosphorylating phosphoinositides to generate secondary signaling molecules crucial for regulating various cellular processes, including cell growth, survival, and metabolism. The PI3K is a heterodimeric enzyme complex comprising of a catalytic subunit (p110α, p110ß, or p110δ) and a regulatory subunit (p85). The binding of the regulatory subunit, p85, with the catalytic subunit, p110, forms an integral component of the PI3K enzyme. PIK3R1 (phosphoinositide-3-kinase regulatory subunit 1) belongs to class IA of the PI3K family. PIK3R1 exhibits structural complexity due to alternative splicing, giving rise to distinct isoforms, prominently p85α and p55α. While the primary p85α isoform comprises multiple domains, including Src homology 3 (SH3) domains, a Breakpoint Cluster Region Homology (BH) domain, and Src homology 2 (SH2) domains (iSH2 and nSH2), the shorter isoform, p55α, lacks certain domains present in p85α. In this review, we will highlight the intricate regulatory mechanisms governing PI3K signaling along with the impact of PIK3R1 alterations on cellular processes. We will further delve into the clinical significance of PIK3R1 mutations in various cancer types and their implications for prognosis and treatment outcomes. Additionally, we will discuss the evolving landscape of targeted therapies aimed at modulating PI3K-associated pathways. Overall, this review will provide insights into the dynamic interplay of PIK3R1 in cancer, fostering advancements in precision medicine and the development of targeted interventions.

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Calcium ions (Ca2+) regulate cell proliferation and differentiation and participate in various physiological activities of cells. The calcium transfer protein inositol 1,4,5-triphosphate receptor (IP3R), located between the endoplasmic reticulum (ER) and mitochondria, plays an important role in regulating Ca2+ levels. However, the mechanism by which IP3R1 affects porcine meiotic progression and embryonic development remains unclear. We established a model in porcine oocytes using siRNA-mediated knockdown of IP3R1 to investigate the effects of IP3R1 on porcine oocyte meiotic progression and embryonic development. The results indicated that a decrease in IP3R1 expression significantly enhanced the interaction between the ER and mitochondria. Additionally, the interaction between the ER and the mitochondrial Ca2+ ([Ca2+]m) transport network protein IP3R1-GRP75-VDAC1 was disrupted. The results of the Duolink II in situ proximity ligation assay (PLA) revealed a weakened pairwise interaction between IP3R1-GRP75 and VDAC1 and a significantly increased interaction between GRP75 and VDAC1 after IP3R1 interference, resulting in the accumulation of large amounts of [Ca2+]m. These changes led to mitochondrial oxidative stress, increased the levels of reactive oxygen species (ROS) and reduced ATP production, which hindered the maturation and late development of porcine oocytes and induced apoptosis. Nevertheless, after treat with [Ca2+]m chelating agent ruthenium red (RR) or ROS scavenger N-acetylcysteine (NAC), the oocytes developmental abnormalities, oxidative stress and apoptosis caused by Ca2+ overload were improved. In conclusion, our results indicated IP3R1 is required for meiotic progression and embryonic development by regulating mitochondrial calcium and oxidative damage.

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