Development Of Pathology Research Articles

Chronic circadian stress raises mean arterial pressure in male, but not female, Bmal1-knockout rats

Shiftwork and other forms of circadian disruption are associated with an increased risk of cardiovascular and kidney disease, however, the mechanisms driving these associations have yet to be elucidated. It has been suggested that dyssynchrony between the endogenous molecular clock and the external environment during shiftwork may be connected with the development of cardiorenal pathologies and the dysregulation of blood pressure (BP). Brain and muscle arntl-like protein 1, or Bmal1, is a core component of the molecular clock. Loss of Bmal1 in both male and female rats results in lower BP compared to wild-type (WT) littermate controls. We hypothesized that Bmal1 is necessary for the acclimation to circadian stress induced by chronic circadian stress (CCS). Telemeters were surgically implanted in the abdominal aorta of 12-14 week old rats. After a 2 week recovery, animals were placed in a light-controlled room on a 12:12hr light/dark cycle. After 1 week acclimation, lights were phase-advanced 6hrs every week for 4 weeks. Telemetry data was collected for 2 minutes every 10 minutes each hour at 1000 samples/second and analyzed using cosinor analysis. The MESOR of mean arterial pressure (MAP) was similar pre- and post- CCS in male WT rats (n=8, 107±1 vs. 109±1 mmHg; 2-way ANOVA, p>0.05) and in female WT rats (n=9, 110±1 vs. 112±2 mmHg; p>0.05). Male Bmal1-KO rats (n=9) had higher MAP MESOR after CCS (103±1 vs 108±1mmHg; p<0.05), but female Bmal1-KO rats (n=6) had no change in MAP MESOR after CCS (100±2. vs 100±2 mmHg, p>0.05). MAP amplitude was similar between WT and KO males before- (6.5±0.7 vs. 5.2±0.8 mmHg) and after-CCS (5.1±0.4 vs. 5.3±0.4 mmHg, p>0.05). WT and KO females had similar MAP amplitude before- (7.2±0.6 vs 5.5±0.9 mmHg) and after-CCS (5.7±1.1 vs. 5.6±0.6, p>0.05). In summary, loss of Bmal1 combined with circadian stress resulted in higher BP in a sex- dependent manner. Despite having lower blood pressures pre-CCS, male Bmal1-KO rats had higher MAP after CCS while female Bmal1-KO rats were protected from increased BP. This suggests that Bmal1, a crucial component of the molecular clock, has a sex-specific role in BP regulation and the response to stress. This work is supported by NIH TL1DK139566-01. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Abstract 2039: Limb Flexion Compresses The Anterior Tibial Artery And Changes Its Take-off Angle In A Sex-Dependent Manner

Introduction: Peripheral Arterial Disease (PAD) operations and reconstructions continue to fail at high rates, particularly below the knee. During limb flexion, distal superficial femoral and popliteal arteries experience significant deformations that are thought to contribute to disease development, but the biomechanics of the tibial arteries below the knee have not been characterized. Methods: Perfused human cadavers (n=15, 81±9 years old, range 60-93 years, 9F/6M) were imaged with their limbs in standing (180°), walking (110°), sitting (90°), and fetal/gardening (60°) positions using Computerized Tomography (CT). Three-dimensional geometries of the below-knee arteries were reconstructed in Mimics software and used to assess the take-off angle of the anterior tibial artery (AT) and the distance from the AT take-off to the nearest AT side branch. Results: The AT take-off angle relative to the tibioperoneal trunk increased with more acute limb flexion, from 70±19° in standing to 81±24° in walking, 83±24° in sitting, and 89±27° in fetal/gardening postures (p<0.01 for all postures). The AT take-off angle was larger in females than in males (24% in standing and 35% in walking, sitting, and gardening postures, p <0.01), but there were no differences between left and right limbs of either sex (p=0.66-0.99). The distance from the AT take-off to the nearest AT side branch decreased with more acute limb flexion (p< 0.01 for all postures). Conclusions: Limb flexion increases the AT take-off angle in a sex-dependent manner and compresses the AT, potentially contributing to the differences in hemodynamics and arterial mechanics and affecting the development and progression of tibial artery pathology. A better understanding of the below-knee artery biomechanics can provide valuable insights for surgical planning and may lead to improvements in the success rate and durability of PAD repairs.

Cardiac Remodeling in Aged Rats after Early-life Chronic Stress: Sex-specific Outcomes and Associations with Metabolic Parameters

Cardiovascular disease is the leading cause of death worldwide. Additionally, the incidence of cardiovascular disease varies both across the lifespan and between sexes. While multiple factors influence the development and progression of cardiovascular pathology, prolonged stress is a prominent risk factor for adverse cardiac events. However, the interactions between stress, sex, and aging that impact cardiac susceptibility remain to be determined. To this end, we examined hypertrophy of the aged myocardium in a sex- and stress-specific manner. We hypothesized that sex and stress history would interact to predict cardiac outcomes and that susceptibility/resilience would associate with behavioral, endocrine, and metabolic parameters assessed across the lifespan. In this study, rats were either exposed to chronic variable stress (CVS) in late adolescence (n = 36/sex) or remained as unstressed controls (n = 24/sex). Rats were subsequently challenged with a forced swim test (FST) and glucose tolerance test (GTT) before ageing to 15 months. The FST and GTT were then repeated prior to tissue collection. Cardiac tissue was processed for histological analysis and quantification of ventricular morphology. The data indicated that early-life chronic stress had sex-specific consequences on the aged left ventricle as CVS females had greater concentric hypertrophy. Based on the level of inward remodeling, rats were then classified as susceptible or resilient. Multiple behavioral and endocrine factors in young and aged animals significantly interacted with hypertrophy, including coping behaviors and glucocorticoid responses to hyperglycemia. However, correlations with hypertrophy were only present in males. Male rats that were not exposed to CVS had a positive association between baseline corticosterone and hypertrophy. Alternatively, CVS males had a positive correlation between visceral adiposity and hypertrophy. Thus, sex-specific cardiac susceptibility/resilience relates to endocrine and metabolic measures depending on stress history. This outcome suggests that adverse experiences can have lasting impacts on homeostatic adaptation. Ultimately, these results highlight the importance of sex and prior stress exposure for disparities in cardiovascular risk. NIH R01 HL 150559 (B Myers) NIHH F30 OD032120 (C Dearing) Pilot Translation Research Program grant from the University of Cincinnati (B Myers). This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Clinical Outcomes and Resource Utilization in Patients With Peripheral Arterial Disease Hospitalized for Acute Coronary Syndrome

Previous studies have shown an association between acute limb ischemia and higher mortality in patients with Acute Myocardial Infarction. Although Peripheral Artery Disease is a well-known risk factor for development of macrovascular pathology, the effect of its severity is not well investigated in patients hospitalized for Acute Coronary Syndrome (ACS). Using a national cohort of patients with various degrees of Peripheral Arterial Disease, we investigated in-hospital outcomes in patients who were admitted for ACS. Using the 2016-2020 Nationwide Readmissions Database, we queried all patients who were hospitalized for ACS (Unstable Angina, Non ST-Elevation Myocardial Infarction, and ST-Elevation Myocardial Infarction). Patients were further divided into three groups, either No Peripheral Arterial Disease (Non-PAD), Peripheral Arterial Disease (PAD) or Critical Limb Ischemia (CLI). Multivariable models were designed to adjust for patient and hospital factors and examine the association between ACS and PAD severity. Of an approximately 3,834,181 hospitalizations for ACS, 6.4% had PAD, 0.2% had CLI and all other were Non-PAD. Following risk adjustment, in hospital mortality was higher by 24% in PAD (AOR 1.24, 95%CI 1.21-1.28) and 86% in CLI (AOR 1.86, 95%CI 1.62-2.09) compared to Non-PAD. Furthermore, PAD and CLI were linked to 1.23-fold (95%CI 1.20-1.26) and 1.67-fold (95%CI 1.45-1.86) greater odds of cardiogenic shock compared to Non-PAD. Additionally, PAD and CLI were linked with higher odds of mechanical circulatory support usage, cardiac arrest and acute kidney injury compared to Non-PAD. Lastly, duration of hospital stay, hospitalization costs and odds of non-home discharge and 30-day readmissions were greater in patients with PAD and CLI compared to Non-PAD. PAD severity was associated with worse clinical outcomes in patients with ACS, including in hospital mortality and resource utilization.

Positron Emission Tomography with [18F]ROStrace Reveals Progressive Elevations in Oxidative Stress in a Mouse Model of Alpha-Synucleinopathy.

The synucleinopathies are a diverse group of neurodegenerative disorders characterized by the accumulation of aggregated alpha-synuclein (aSyn) in vulnerable populations of brain cells. Oxidative stress is both a cause and a consequence of aSyn aggregation in the synucleinopathies; however, noninvasive methods for detecting oxidative stress in living animals have proven elusive. In this study, we used the reactive oxygen species (ROS)-sensitive positron emission tomography (PET) radiotracer [18F]ROStrace to detect increases in oxidative stress in the widely-used A53T mouse model of synucleinopathy. A53T-specific elevations in [18F]ROStrace signal emerged at a relatively early age (6-8 months) and became more widespread within the brain over time, a pattern which paralleled the progressive development of aSyn pathology and oxidative damage in A53T brain tissue. Systemic administration of lipopolysaccharide (LPS) also caused rapid and long-lasting elevations in [18F]ROStrace signal in A53T mice, suggesting that chronic, aSyn-associated oxidative stress may render these animals more vulnerable to further inflammatory insult. Collectively, these results provide novel evidence that oxidative stress is an early and chronic process during the development of synucleinopathy and suggest that PET imaging with [18F]ROStrace holds promise as a means of detecting aSyn-associated oxidative stress noninvasively.

Identification of chemical transformations in enamel apatite during the development of fissure caries at the nanoscale by means of synchrotron infrared nanospectroscopy: A pilot study

The spectral data sets obtained in our work using classical micro Fourier transform infrared spectroscopy (μFTIR) and modern broadband synchrotron infrared nanospectroscopy (SINS) methods, as well as their analysis and comparison with the known μFTIR spectroscopic results, provide new fundamental information on the mechanisms of pathological processes development in the carious fissure region of a human tooth at the level of enamel apatite crystallites (nano level). The infrared vibration signatures detected in our nanoscale study allowed us to establish gradient changes in chemical composition (phase transformations) occurring within the enamel roads at the level of apatite nanocrystals forming a prism, also to estimate changes in the crystallinity coefficient and the proportion of acid phosphates, as well as the depth of bacteria metabolism products (acid invasion). The results of the comparative study of this technique demonstrate that the combination of s-SNOM, IR spectroscopy and synchrotron broadband source in the SINS method provides excellent chemical sensitivity, sufficient for the providing of chemical identification of phase transformations with enhanced spatial resolution of ∼25 nm and the depth of useful signal output of several tens of nanometers. These advantages of SINS claim to be an advanced approach for investigations of objects of biological nature at a qualitatively new level.

Transcriptomic and developmental effects of persistent organic pollutants in sentinel fishes collected near an arctic formerly used defense site

Alaska contains over 600 formerly used defense (FUD) sites, many of which serve as point sources of pollution. These sites are often co-located with rural communities that depend upon traditional subsistence foods, especially lipid-rich animals that bioaccumulate and biomagnify persistent organic pollutants (POPs). Many POPs are carcinogenic and endocrine-disrupting compounds that are associated with adverse health outcomes. Therefore, elevated exposure to POPs from point sources of pollution may contribute to disproportionate incidence of disease in arctic communities. We investigated PCB concentrations and the health implications of POP exposure in sentinel fishes collected near the Northeast Cape FUD site on Sivuqaq (St. Lawrence Island), Alaska. Sivuqaq residents are almost exclusively Yupik and rely on subsistence foods. At the request of the Sivuqaq community, we examined differential gene expression and developmental pathologies associated with exposure to POPs originating at the Northeast Cape FUD site. We found significantly higher levels of PCBs in Alaska blackfish (Dallia pectoralis) collected from contaminated sites downstream of the FUD site compared to fish collected from upstream reference sites. We compared transcriptomic profiles and histopathologies of these same blackfish. Blackfish from contaminated sites overexpressed genes involved in ribosomal and FoxO signaling pathways compared to blackfish from reference sites. Contaminated blackfish also had significantly fewer thyroid follicles and smaller pigmented macrophage aggregates. Conversely, we found that ninespine stickleback (Pungitius pungitius) from contaminated sites exhibited thyroid follicle hyperplasia. Despite our previous research reporting transcriptomic and endocrine differences in stickleback from contaminated vs. reference sites, we did not find significant differences in kidney or gonadal histomorphologies. Our results demonstrate that contaminants from the Northeast Cape FUD site are associated with altered gene expression and thyroid development in native fishes. These results are consistent with our prior work demonstrating disruption of the thyroid hormone axis in Sivuqaq residents.

An Innovative Apical-4-Chamber-long-axis Imaging Approach Precisely Tracks Progressive Deterioration of Mouse Ventricles, Atria, and Atrioventricular Valves

Transthoracic echocardiography stands as the primary non-invasive method for cardiac function evaluation in clinical settings. It’s widely used to assess chamber sizes, heart wall integrity, as well as the hemodynamic performance of the left ventricle (LV), right ventricle (RV), atria, and valves. However, applying comprehensive echocardiography assessments to mice has been challenging, primarily due to diffculties in obtaining on-axis apical 4-chamber views; most mouse studies have thus been restricted to evaluating the LV using short-axis M-mode assays. To overcome this limitation, we’ve recently developed a novel methodology to consistently obtain high-quality apical 4-chamber-long-axis (A4CLAX) view images of mouse heart. This advancement permits a range of clinically relevant functional assessments, including Long Axis Biplane (LAX-BP) assay, which has been shown to surpasses M-mode in estimating LV function. In this study, we delve into the breadth of comprehensive echocardiography assessments made possible for mice through the A4CLAX imaging approach. We performed a severe transverse aortic constriction (TAC) surgery on mice and monitored the pathological development in their hearts post-surgery. Alongside the expected hypertrophy, the LAX-BP assay revealed LV volumetric dilation as early as 1-week after TAC surgery Indicative of decompensated heart failure; however, m-mode was not able to pick up on this early dilation due to its lack of longitudinal assessment and inconsistent measurements of EDV and ESV. The apical 4 chamber view significantly improved the consistency and reliability of trans mitral and pulmonary vein doppler recordings and enabled us to reliably estimate the pressure relationships of the LV and Left Atrial (LA) pressure, which is consistent with the LAX-BP detected LV decompensation. Additionally, the high clarity of the 4 chamber images achieved improved visualization of both mitral and tricuspid valve leaflets. This allowed more precise characterization of valvular issues, including mitral regurgitation caused by LV dilatation, as well as identification of less common pathological occurrences like desynchronization of the tricuspid and mitral valve opening. A speckle tracking assay of the Right ventricle (RV) showed that a delayed contraction of the lateral apical RV wall caused the tricuspid valve to not open during the early filling phase, but rather at the atrial kick, leading to this valve desynchrony. This delayed contraction indicates a possible elevation of pulmonary pressure, as evidenced by pulmonary vein doppler indices and the analysis of pulmonary congestion. In conclusion, the innovative A4CLAX imaging technique revolutionizes murine heart analysis, bringing it in line with clinical echocardiography standards allowing for a whole heart analysis approach. It sensitively identifies subtle anomalies, providing a precise characterization of cardiac remodeling and disease progression in mouse hearts. This study has been supported by grants NIH-R01HL139006 and R21OD031965. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Analyzing Pelvic Asymmetry by Sex and Ancestry: Insights From an Osteological Collection.

Pelvic asymmetry has been noted in pelvic imaging, and might influence the development of various spinal pathologies, most notably scoliosis. There is a limited understanding of the relationship between pelvic asymmetry and sex and ancestry, and limited use of 3D modeling. The purpose of this study was to identify pelvic asymmetry and morphology differences between sex and ancestry utilizing 3D modeling on young adults in an osteological collection. Thirty-three osteological pelvic specimens aged 18-25 years (average age 21.4 ± 2.0 years) were scanned to create virtual 3D models for analysis. Pelvic asymmetry and morphology were measured and compared across sex (male and female) and ancestry (European American and African American). Multivariate regression analysis was performed to examine the relationship between the variables measured. Multivariate regression analysis demonstrated statistically significant relationships between innominate-pelvic ring ratio and both sex (p < 0.001) and ancestry (p= 0.003) with larger ratios in male and African American specimens respectively. There was also a statistically significant relationship of greater sacral 1 coronal tilt in European American specimens (p= 0.042). There were no statistically significant differences with sex or ancestry in terms of innominate or sacral asymmetry. Although there are differences in overall pelvic shape between sex and ancestry, there is no relationship between these two variables versus pelvic asymmetry in the axial or sagittal planes in young adult osteological specimens.

Significance of erythropoesis correction in preoperative preparation in the surgical treatment of patients with colorectal cancer

Background. Anemic syndrome, which accompanies the development of pathology in patients with colorectal cancer, can cause serious early postoperative complications. The question of how preoperative preparation activities influence the state of the intestinal structures and the clinical situation in general is relevant. Of particular importance in this situation is the correction of anemic syndrome before surgery, using hematopoietic stimulants. Objective. The purpose of the study is to analyze the dynamics of erythropoiesis and changes in tissue and cell ultrastructure in intraoperative colon biopsy specimens after stimulation of erythropoiesis in preoperative preparation in the surgical treatment of patients with colorectal cancer. Methods. The study of red bone marrow and the wall of the large intestine using transmission electron microscopy. Results. Most patients with colorectal cancer are characterized by the development of signs of ineffective erythropoiesis with a moderate slowdown in the differentiation of erythroblasts and a delay in the release of mature erythrocytes into the systemic circulation. Stimulation of erythropoiesis with the help of epoetin leads to an increase in the functional activity of the central macrophages of the erythropoietic islets of the red bone marrow and the enhancement of their intercellular association with maturing erythroid cells. This is accompanied by the formation of a large number of full-fledged erythrocytes, an increase in the numerical density of cells of the erythroid series and the normalization of their ultrastructure. Conclusion. Stimulation of erythropoiesis with the help of epoetin in the preoperative period causes the inhibition of endothelial dysfunction due to the restriction of dystrophic and destructive changes in endothelial cell organelles, stabilization of their membranes, prevention of arteriole spasm, erythrocyte stasis and erythrocyte phenomena. As a result, the phenomena of infiltration, perivascular and interstitial edema in the composition of the membranes of the intestinal wall are much less pronounced than in the group of patients without preoperative activation of erythropoiesis.

Pathology of the gastrointestinal tract in overweight and obese children

Obesity and diseases of the gastrointestinal tract are widespread among the children and have common developmental mechanisms. The article provides a literature review on the relationships between certain pathological conditions of the digestive system (gastroesophageal reflux disease, gastritis, functional intestinal disorders, Crohn’s disease, diverticular disease) in children with overweight and obesity. Excess body weight and obesity can become risk factors for the development of gastrointestinal pathology. The data available in modern literature on changes in the composition of the intestinal and stomach microbiocenosis with increasing body weight are summarized (changes in enterotype, increase in the Firmicutеs/Bacteroides ratio, increase in the number of bacteria Methanobrevibacter, Escherichia coli, Lactobacillus rhamnosus, Lactobacillus delbrueckii and Lactobacillus reuteri). The strains of bacteria that contribute to the anorexigenic effect are considered: Lactobacillus gasseri, some strains of Bifidobacterium, Saccharomyces, Streptococcus and Enterococcus. The pathogenetic aspects of obesity and overweight caused by microbiota are presented: activation of lipid synthesis, breakdown of polysaccharides, absorption of mono- and disaccharides, development of metabolic endotoxemia, etc. Features of the functioning of the autonomic nervous system in obesity in children are presented, indicating the predominance of the hypersympathicotonic variant of autonomic reactivity.

Arbovirus infection increases the risk for the development of neurodegenerative disease pathology in the murine model

Alzheimer's disease is classified as a progressive disorder resulting from protein misfolding, also known as proteinopathies. Proteinopathies include synucleinopathies triggered by misfolded amyloid α-synuclein, tauopathies triggered by misfolded tau, and amyloidopathies triggered by misfolded amyloid of which Alzheimer's disease (β-amyloid) is most prevalent. Most neurodegenerative diseases (>90%) are not due to dominantly inherited genetic causes. Instead, it is thought that the risk for disease is a complicated interaction between inherited and environmental risk factors that, with age, drive pathology that ultimately results in neurodegeneration and disease onset. Since it is increasingly appreciated that encephalitic viral infections can have profoundly detrimental neurological consequences long after the acute infection has resolved, we tested the hypothesis that viral encephalitis exacerbates the pathological profile of protein-misfolding diseases. Using a robust, reproducible, and well-characterized mouse model for β-amyloidosis, Tg2576, we studied the contribution of alphavirus-induced encephalitis (TC-83 strain of VEEV to model alphavirus encephalitis viruses) on the progression of neurodegenerative pathology. We longitudinally evaluated neurological, neurobehavioral, and cognitive levels, followed by a post-mortem analysis of brain pathology focusing on neuroinflammation. We found more severe cognitive deficits and brain pathology in Tg2576 mice inoculated with TC-83 than in their mock controls. These data set the groundwork to investigate sporadic Alzheimer's disease and treatment interventions for this infectious disease risk factor.

P178 CXCL12/CXCR4-mediated osteogenic precursor cells recruitment: a key mechanism in ankylosing spondylitis-associated pathological bone formation

Abstract Background/Aims Ankylosing spondylitis (AS) is a debilitating condition characterised by severe spinal deformities, inflammation, and excessive bone formation, imposing significant socioeconomic burdens. Current treatments alleviate symptoms but fail to address bone structural damage. Pathological bone formation often occurs at entheses, where tendons and ligaments connect to bone. Osteogenic precursor cells (OPCs) play a crucial role, but their migration to new bone sites is poorly understood. C-X-C motif chemokine ligand 12 (CXCL12) is implicated in cell migration and bone-related processes, but its role in AS remains unclear. This study explores CXCL12/CXCR4 signalling in OPC recruitment and new bone formation, providing insights into AS pathogenesis and potential therapeutic targets. Methods We established mouse models, including the DBA/1 model, lipopolysaccharide-induced spondyloarthritis model, and Achilles tendon semi-transection model to confirm the role of CXCL12-Induced OPCs migration in pathological new bone formation. Additionally, genetically edited mouse models were generated to confirm the underlying mechanism of OPCs migration and their spatiotemporal phenotypes of differentiation, including DBA1;CXCL12 col2 transgenic mice, CXCL12hi/hi;Col2a1-creERT mice, and CXCR4fl/fl;Prx1-creERT mice. Results In this study, we have identified CXCL12 as a crucial contributor to the initiation of pathological new bone formation by recruiting OPCs. CXCL12 was highly expressed in regions predisposed to pathological bone development, attracting OPCs to these upregulated areas. Inhibiting the CXCL12/CXCR4 axis with AMD3100 or the conditional knockout of CXCR4 effectively reduced OPC migration and subsequent pathological bone formation in animal models of AS. Overexpression of CXCL12 in genetically engineered animals with a DBA/1 background demonstrated a stable joint ankylosis phenotype, providing a valuable model for the study of AS. Furthermore, our research revealed the indispensable role of Rac1 in OPC migration and the ensuing pathological bone formation. Conclusion This study elucidates the novel role of CXCL12 in AS and offers potential strategies for targeting the CXCL12/CXCR4-Rac1 axis to prevent the progression of axial skeletal ankylosis. Disclosure H. Cui: None. H. Liu: None.

GFRA4 improves the neurogenic potential of enteric neural crest stem cells via hedgehog pathway.

Hirschsprung disease (HSCR) is a congenital intestinal disease characterised by functional obstruction of the colon. Herein, we investigated the role and mechanism of the gene GFRA4 in HSCR. GFRA4 expression in the ganglionic and aganglionic segment tissues in patients with HSCR and healthy colon tissues were detected using qRT-PCR, western blot, and immunohistochemistry. Cell proliferation, cycle distribution, apoptosis, changes in mitochondrial membrane potential, and differentiation were assessed in mouse enteric neural crest stem cells (ENCSCs) using the CCK-8 assay, EdU staining, flow cytometry, JC-1 probe, and immunofluorescence, respectively. GSEA analysis was performed to screen the signaling pathways regulated by GFRA4. GFRA4 was downregulated in aganglionic segment tissues compared to control and ganglionic segment tissues. GFRA4 overexpression promoted proliferation and differentiation, and inhibited apoptosis in ENCSCs, while GFRA4 down-regulation had the opposite result. GFRA4 activated the hedgehog pathway. GFRA4 overexpression enhanced the expression of key factors of the hedgehog pathway, including SMO, SHH, and GLI1. However, GFRA4 down-regulation reduced their expression. An antagonist of hedgehog pathway, cyclopamine, attenuated the effect of GFRA4 overexpression on proliferation, differentiation, and apoptosis of ENCSCs. GFRA4 promotes proliferation and differentiation but inhibits apoptosis of ENCSCs via the hedgehog pathway in HSCR. This study confirms that GFRA4 improves the proliferation and differentiation of ENCSCs via modulation of the hedgehog pathway. This study for the first time revealed the role and the mechanism of the action of GFRA4 in HSCR, which indicates that GFRA4 may play a role in the pathological development of HSCR. Our findings may lay the foundation for further investigation of the mechanisms underlying HSCR development and into targets of HSCR treatment.

Downregulation of Glis3 in INS1 cells exposed to chronically elevated glucose contributes to glucotoxicity-associated β cell dysfunction

ABSTRACT Chronically elevated levels of glucose are deleterious to pancreatic β cells and contribute to β cell dysfunction, which is characterized by decreased insulin production and a loss of β cell identity. The Krüppel-like transcription factor, Glis3 has previously been shown to positively regulate insulin transcription and mutations within the Glis3 locus have been associated with the development of several pathologies including type 2 diabetes mellitus. In this report, we show that Glis3 is significantly downregulated at the transcriptional level in INS1 832/13 cells within hours of being subjected to high glucose concentrations and that diminished expression of Glis3 is at least partly attributable to increased oxidative stress. CRISPR/Cas9-mediated knockdown of Glis3 indicated that the transcription factor was required to maintain normal levels of both insulin and MafA expression and reduced Glis3 expression was concomitant with an upregulation of β cell disallowed genes. We provide evidence that Glis3 acts similarly to a pioneer factor at the insulin promoter where it permissively remodels the chromatin to allow access to a transcriptional regulatory complex including Pdx1 and MafA. Finally, evidence is presented that Glis3 can positively regulate MafA transcription through its pancreas-specific promoter and that MafA reciprocally regulates Glis3 expression. Collectively, these results suggest that decreased Glis3 expression in β cells exposed to chronic hyperglycemia may contribute significantly to reduced insulin transcription and a loss of β cell identity.

Targeting MetaLnc9/miR-143/FSCN1 axis inhibits oxidative stress and myofibroblast transdifferentiation in oral submucous fibrosis

Background/purposePersistent activation of myofibroblasts is attributed to various dysregulated biological events conferring multiple types of fibrosis diseases, including oral submucous fibrosis (OSF). Although the significance of non-coding RNAs (ncRNAs) in the occurrence of fibrosis has been appreciated, the detailed mechanisms still have not been fully elucidated. The aim of this study was to identify key dysregulated ncRNAs and elucidate their pro-fibrotic mechanisms in promoting myofibroblast activation and the pathological development of OSF. Materials and methodsExpression of non-coding RNAs and mRNAs in OSF cohort was determined using RNA sequencing and qRT-PCR. The molecular axis of pro-fibrotic ncRNAs were exploited via luciferase reporter activity assay and RNA expression rescue experiments. Functional assays, including collagen gel contraction, wound healing ability, cell migration, and reactive oxygen species (ROS) production, were conducted to assess the changes in the myofibroblastic phenotypes of primary human buccal mucosal fibroblasts. ResultsHerein, we found that long non-coding RNA MetaLnc9 was upregulated in OSF specimens and positively associated with several fibrosis markers. Silencing of MetaLnc9 diminished the features of activated myofibroblasts and the production of ROS. We not only showed that MetaLnc9 functioned as a competitive endogenous RNA of microRNA (miR)-143, but also demonstrated that the pro-fibrosis effect of MetaLnc9 on myofibroblast activities was mediated by suppression of miR-143. Moreover, our data showed that fascin actin-bundling protein 1 (FSCN1) was a direct target of miR-143 and positively related to MetaLnc9. ConclusionUpregulation of MetaLnc9 may enhance the activation of myofibroblasts by sponging miR-143 and titrating its inhibitory property on FSCN1.

Porcine computational modeling to investigate developmental dysplasia of the hip.

While it is well-established that early detection and initiation of treatment of developmental dysplasia of the hip (DDH) is crucial to successful clinical outcomes, research on the mechanics of the hip joint during healthy and pathological hip development in infants is limited. Quantification of mechanical behavior in both the healthy and dysplastic developing joints may provide insight into the causes of DDHand facilitate innovation in treatment options. In this study, subject-specific three-dimensional finite element models of two pigs were developed: one healthy pig and one pig with induced dysplasia in the right hindlimb. The objectives of this study were: (1) to characterize mechanical behavior in the acetabular articular cartilage during a normal walking cycle by analyzing six metrics: contact pressure, contact area, strain energy density, von Mises stress, principal stress, and principal strain; and (2) to quantify the effect on joint mechanics of three anatomic abnormalities previously identified as related to DDH: variation in acetabular coverage, morphological changes in the femoral head, and changes in the articular cartilage. All metrics, except the contact area, were elevated in the dysplastic joint. Morphological changes in the femoral head were determined to be the most significant factors in elevating contact pressure in the articular cartilage, while the effects of acetabular coverage and changes in the articular cartilage were less significant. The quantification of the pathomechanics of DDH in this study can help identify key mechanical factors that restore normal hip development and can lead to mechanics-driven treatment options.

Speech Sounds Production, Narrative Skills, and Verbal Memory of Children with 22q11.2 Microdeletion.

22q11.2 deletion syndrome (22q11.2DS), the most frequent microdeletion syndrome in humans, is related to a high risk of developing neurodevelopmental disorders. About 95% of patients with 22q11.2DS have speech and language impairments. Global articulation, story generation, and verbal memory tests were applied to compare articulatory characteristics of speech sounds, spontaneous language abilities, and immediate verbal memory between four groups of Serbian-speaking children: patients with 22q11.2DS, children with clinical presentation of 22q11.2DS that do not have the microdeletion, children with non-syndromic congenital heart defects, and their peers with typical speech-sound development. The obtained results showed that children with this microdeletion have impaired articulation skills and expressive language abilities. However, we did not observe weaker receptive language skills and immediate verbal memory compared to healthy controls. Children with 22q11.2DS should be considered a risk category for the development of speech-sound pathology and expressive language abilities. Since speech intelligibility is an instrument of cognition and adequate peer socialization, and language impairment in school-aged children with 22q11DS might be an indicator of increased risk for later psychotic symptoms, patients with 22q11.2 microdeletion should be included in a program of early stimulation of speech-language development immediately after diagnosis is established.

The effectiveness of treatment depending on an adherence to dispensary observation and antiretroviral therapy in patients with HIV infection

Aim. Determination of the causes of deaths and analysis of the survival of people living with HIV, depending on an adherence to dispensary observation and treatment. Materials and methods. The analysis of socio-demographic characteristics and clinical and laboratory data of 284 adult HIV patients observed in 1999–2011 at the Lomonosov Interdistrict Hospital named after I. N. Yudchenko was carried out. Patients who followed the prescribed monitoring regimen (at least 2 times a doctor’s visit during the year) were considered committed to dispensary supervision. Patients who observed the regularity and continuity of monitoring and receiving antiretroviral therapy (ART) were considered committed to treatment. Among the patients included in the study, 115 people were committed to treatment or follow-up and 169 patients were non-committed. Objective (biological) indicators of adherence and effectiveness of treatmentwere the number of CD4 lymphocytes and the level of HIV viral load. Based on the method of comparing survival curves, factors related to the life expectancy of HIV patients were assessed, taking into account the gender of patients, their adherence to monitoring and treatment, indicators of HIV viral load and the number of CD4 lymphocytes and the outcome of the disease from the moment of registration at the dispensary and over the next 120 months (after 3 months, 6 months, 1.5 years, 2 years, 5, 7 and 10 years). Results and discussion. Significant differences were found in the survival curves of patients who received and did not receive ART (117.9 and 91.4 months, p&lt;0.005) and patients who were committed and non-committed to therapy (116.9 and 83.8 months, p&lt;0.005). Regardless of adherence to outpatient follow-up and therapy, the survival time of women compared to men for the entire follow-up period was longer (105.0 and 92.4 months, respectively, p&lt;0.005). Among those committed to treatment, 21% of patients died due to concomitant somatic pathology, 5% from injuries incompatible with life. In the group of those committedto follow–up, the causes of deaths in 12% were various somatic pathology, brain lymphoma — in 1% and injuries incompatible with life — in 3% of cases. The highest mortality rates were recorded among patients who were not exposed to ART (71%) and the routine of follow-up (52%). Almost half of these patients (49%) died from secondary HIV infections, of which 85% of cases were posthumously diagnosed with tuberculosis, mainly the pulmonary form of the disease. The second most common cause of death was violent death, including drug poisoning. Conclusion. Regular dispensary observation, timely initiation of ART and adherence to therapy make it possible to control the disease, prevent the development of opportunistic pathology, and improve the quality and life expectancy of patients with HIV infection. Despite the increased availability of ART and strategies for active involvement and retention of patients in dispensary care, issues of patient adherence to therapy remain key in the management of HIV patients.

Traumatic Brain Injury and Post-Traumatic Stress Disorder and Their Influence on Development and Pattern of Alzheimer's Disease Pathology in Later Life.

Traumatic brain injury (TBI) and posttraumatic stress disorder (PTSD) are potential risk factors for the development of dementia including Alzheimer's disease (AD) in later life. The findings of studies investigating this question are inconsistent though. To investigate if these inconsistencies are caused by the existence of subgroups with different vulnerability for AD pathology and if these subgroups are characterized by atypical tau load/atrophy pattern. The MRI and PET data of 89 subjects with or without previous TBI and/or PTSD from the DoD ADNI database were used to calculate an age-corrected gray matter tau mismatch metric (ageN-T mismatch-score and matrix) for each subject. This metric provides a measure to what degree regional tau accumulation drives regional gray matter atrophy (matrix) and can be used to calculate a summary score (score) reflecting the severity of AD pathology in an individual. The ageN-T mismatch summary score was positively correlated with whole brain beta-amyloid load and general cognitive function but not with PTSD or TBI severity. Hierarchical cluster analysis identified five different spatial patterns of tau-gray matter interactions. These clusters reflected the different stages of the typical AD tau progression pattern. None was exclusively associated with PTSD and/or TBI. These findings suggest that a) although subsets of patients with PTSD and/or TBI develop AD-pathology, a history of TBI or PTSD alone or both is not associated with a significantly higher risk to develop AD pathology in later life. b) remote TBI or PTSD do not modify the typical AD pathology distribution pattern.