scholarly journals Genetic inhibition of RIPK3 ameliorates functional outcome in controlled cortical impact independent of necroptosis

2021 ◽  
Vol 12 (11) ◽  
Author(s):  
Limin Wu ◽  
Joon Yong Chung ◽  
Tian Cao ◽  
Gina Jin ◽  
William J. Edmiston ◽  
...  
Keyword(s):  
Functional Outcome ◽  
Interleukin 1 ◽  
Three Dimensional ◽  
Molecular Complexes ◽  
Lesion Size ◽  
Object Recognition Test ◽  
Cerebral Contusion ◽  
Interacting Protein ◽  
Driving Mechanisms ◽  
Endothelial Cell Cultures

AbstractTraumatic brain injury (TBI) is a leading cause of death and disability with no specific effective therapy, in part because disease driving mechanisms remain to be elucidated. Receptor interacting protein kinases (RIPKs) are serine/threonine kinases that assemble multi-molecular complexes that induce apoptosis, necroptosis, inflammasome and nuclear factor kappa B activation. Prior studies using pharmacological inhibitors implicated necroptosis in the pathogenesis of TBI and stroke, but these studies cannot be used to conclusively demonstrate a role for necroptosis because of the possibility of off target effects. Using a model of cerebral contusion and RIPK3 and mixed lineage kinase like knockout (MLKL−/−) mice, we found evidence for activation of RIPK3 and MLKL and assembly of a RIPK1-RIPK3-MLKL necrosome complex in pericontusional brain tissue. Phosphorylated forms of RIPK3 and MLKL were detected in endothelium, CD11b + immune cells, and neurons, and RIPK3 was upregulated and activated in three-dimensional human endothelial cell cultures subjected to CCI. RIPK3−/− and MLKL−/− mice had reduced blood-brain barrier damage at 24 h (p < 0.05), but no differences in neuronal death (6 h, p = ns in CA1, CA3 and DG), brain edema (24 h, p = ns), or lesion size (4 weeks, p = ns) after CCI. RIPK3−/−, but not MLKL−/− mice, were protected against postinjury motor and cognitive deficits at 1–4 weeks (RIPK3−/− vs WT: p < 0.05 for group in wire grip, Morris water maze hidden platform trials, p < 0.05 for novel object recognition test, p < 0.01 for rotarod test). RIPK3−/− mice had reduced infiltrating leukocytes (p < 0.05 vs WT in CD11b + cells, microglia and macrophages), HMGB1 release and interleukin-1 beta activation at 24–48 h (p < 0.01) after CCI. Our data indicate that RIPK3 contributes to functional outcome after cerebral contusion by mechanisms involving inflammation but independent of necroptosis.

scholarly journals Pericyte contractility controls endothelial cell cycle progression and sprouting: insights into angiogenic switch mechanics

2014 ◽  
Vol 307 (9) ◽  
pp. C878-C892 ◽  
Author(s):  
Jennifer T. Durham ◽  
Howard K. Surks ◽  
Brian M. Dulmovits ◽  
Ira M. Herman
Keyword(s):  
Cell Cycle Progression ◽  
Network Formation ◽  
Rho Gtpase ◽  
Three Dimensional ◽  
Rho Kinase ◽  
Leading Edge ◽  
Fold Increase ◽  
Cycle Progression ◽  
Interacting Protein ◽  
Angiogenic Switch

Microvascular stability and regulation of capillary tonus are regulated by pericytes and their interactions with endothelial cells (EC). While the RhoA/Rho kinase (ROCK) pathway has been implicated in modulation of pericyte contractility, in part via regulation of the myosin light chain phosphatase (MLCP), the mechanisms linking Rho GTPase activity with actomyosin-based contraction and the cytoskeleton are equivocal. Recently, the myosin phosphatase-RhoA-interacting protein (MRIP) was shown to mediate the RhoA/ROCK-directed MLCP inactivation in vascular smooth muscle. Here we report that MRIP directly interacts with the β-actin-specific capping protein βcap73. Furthermore, manipulation of MRIP expression influences pericyte contractility, with MRIP silencing inducing cytoskeletal remodeling and cellular hypertrophy. MRIP knockdown induces a repositioning of βcap73 from the leading edge to stress fibers; thus MRIP-silenced pericytes increase F-actin-driven cell spreading twofold. These hypertrophied and cytoskeleton-enriched pericytes demonstrate a 2.2-fold increase in contractility upon MRIP knockdown when cells are plated on a deformable substrate. In turn, silencing pericyte MRIP significantly affects EC cycle progression and angiogenic activation. When MRIP-silenced pericytes are cocultured with capillary EC, there is a 2.0-fold increase in EC cycle entry. Furthermore, in three-dimensional models of injury and repair, silencing pericyte MRIP results in a 1.6-fold elevation of total tube area due to EC network formation and increased angiogenic sprouting. The pivotal role of MRIP expression in governing pericyte contractile phenotype and endothelial growth should lend important new insights into how chemomechanical signaling pathways control the “angiogenic switch” and pathological angiogenic induction.

scholarly journals Supramolecular architectures of 4-hydroxytetraphenylporphyrin with aza-donors

2014 ◽  
Vol 70 (a1) ◽  
pp. C554-C554 ◽  
Author(s):  
Purnendu Nandy ◽  
V. Pedireddi
Keyword(s):  
Three Dimensional ◽  
Molecular Complexes ◽  
Hydroxyl Groups ◽  
X Ray Diffraction ◽  
X Ray ◽  
Supramolecular Architectures ◽  
Detailed Structural Analysis ◽  
Different Types ◽  
Solvent Molecules ◽  
Molecular Adducts

Molecular adducts of 5,10,15,20-tetrakis(4-hydroxyphenyl)porphyrin (1) with aza-donors like 4,4'-bipyridine (a), 1,2-bis(4-pyridyl)ethane (b), trans-1,2-bis(4-pyridyl)ethylene (c), 4,4'-trimethylene-dipyridine (d), phenazine (e), 1,10-phenanthroline (f), 1,7-phenanthroline (g) and 4,7-phenanthroline (h) have been prepared. All the molecular complexes are crystallized along with the solvent of crystallization, except in the complex with the aza-donor b. Detailed structural analysis of the obtained complexes has been carried out by single crystal X-ray diffraction. The three dimensional structures of the molecular adducts are facilitated by directional hydrogen bonding features of hydroxyl groups with aza donors as well as solvent molecules, leading to the formation of different types of supramolecular architectures like sheets, tapes, host-guest assembly etc. For example, in the complex of 1 and aza donor a, which crystallizes as a hydrate, the porphyrin molecules interact with water and 4,4'-bipyridine through O-H...O and O-H...N hydrogen bonds, which leads to the formation of molecular sheets in two dimensional arrangement. An important noteworthy observation is that the molecular complexes are crystalline even after removal of the solvents by heating, as characterized by thermogravimetric analysis (TGA) and powder X-ray diffraction (PXRD). Further, all the complexes are found to be fluorescence sensitive, perhaps due to the porphyrin molecules.

scholarly journals Metabolic Syndrome Exacerbates the Recognition Memory Impairment and Oxidative-Inflammatory Response in Rats with an Intrahippocampal Injection of Amyloid Beta 1–42

2018 ◽  
Vol 2018 ◽  
pp. 1-13 ◽  
Author(s):  
Alfonso Diaz ◽  
Claudia Escobedo ◽  
Samuel Treviño ◽  
Raúl Chávez ◽  
Gustavo Lopez-Lopez ◽  
...  
Keyword(s):  
Metabolic Syndrome ◽  
Cognitive Process ◽  
Interleukin 1 ◽  
Temporal Cortex ◽  
Cognitive Disorders ◽  
Object Recognition Test ◽  
Calorie Diet ◽  
Inflammatory Processes ◽  
Cognitive Diseases ◽  
Intrahippocampal Injection

An important worldwide health problem as the result of current lifestyle is metabolic syndrome (MS). It has been shown that MS induced by a high-calorie diet (HCD) in rats produces cognitive deterioration in the novel object recognition test (NORt) and decreases synaptic connections and dendritic order in the hippocampus and temporal cortex. However, it is unknown whether MS induced by an HCD participates in the cognitive process observed with the injection of Aβ1–42 into the hippocampus of rats as a model of Alzheimer disease (AD). The induction of MS in rats produces a deterioration in NORt; however, rats with MS injected with Aβ1–42 show a major deterioration in the cognitive process. This event could be explained by the increment in the oxidative stress in both cases studied (MS and Aβ1–42): together, the hippocampus and temporal cortex produce an enhancer effect. In the same way, we observed an increment in interleukin-1β, TNF-α, and GFAP, indicative of exacerbated inflammatory processes by the combination of MS and Aβ1–42. We can conclude that MS might play a key role in the apparition and development of cognitive disorders, including AD. We propose that metabolic theory is important to explain the apparition of cognitive diseases.

scholarly journals Retrospective accuracy analysis of MRI based lesion size measurement in neuroblastic tumors: which sequence should we choose?

2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Sebastian Gassenmaier ◽  
Ilias Tsiflikas ◽  
Simon Maennlin ◽  
Cristian Urla ◽  
Steven W. Warmann ◽  
...  
Keyword(s):  
Mr Imaging ◽  
Tumor Size ◽  
Three Dimensional ◽  
Lesion Size ◽  
Three Dimensions ◽  
Neuroblastic Tumor ◽  
Significant Difference ◽  
Dimensional Measurements ◽  
Neuroblastic Tumors ◽  
Mri Measurements

Abstract Background MR imaging of neuroblastic tumors is widely used for assessing the effect of chemotherapy on tumor size. However, there are some concerns that MRI might falsely estimate lesion diameters due to calcification and fibrosis. Therefore, the aim of our study was to compare neuroblastic tumor size based on MRI measurements to histopathology measurements of the resected specimens as standard of reference. Methods Inclusion criteria were diagnosis of a neuroblastic tumor, MR imaging within 100 days to surgery and gross total resection without fragmentation of the tumor between 2008 and 2019. Lesion diameters were measured by two radiologists according to RECIST 1.1 in axial plane in T2w turbo spin echo (TSE), diffusion-weighted imaging (DWI), and in T1w pre- and postcontrast sequences. Furthermore, the largest lesion size in three-dimensions was noted. The largest diameter of histopathology measurements of each specimen was used for comparison with MRI. Results Thirty-seven patients (mean age: 5 ± 4 years) with 38 lesions (neuroblastoma: n = 17; ganglioneuroblastoma: n = 11; ganglioneuroma: n = 10) were included in this retrospective study. There was excellent intra-class correlation coefficient between both readers for all sequences (> 0.9) Tumor dimensions of reader 1 based on axial MRI measurements were significantly smaller with the following median differences (cm): T1w precontrast − 1.4 (interquartile range (IQR): 1.8), T1w postcontrast − 1.0 (IQR: 1.9), T2w TSE: -1.0 (IQR: 1.6), and DWI -1.3 (IQR: 2.2) (p < 0.001 for all sequences). However, the evaluation revealed no significant differences between the three-dimensional measurements and histopathology measurements of the resected specimens regardless of the applied MRI sequence. Conclusions Axial MRI based lesion size measurements are significantly smaller than histopathological measurements. However, there was no significant difference between three-dimensional measurements and histopathology measurements of the resected specimens. T2w TSE and T1w postcontrast images provided the lowest deviation and might consequently be preferred for measurements.

scholarly journals Quantifying solute spreading and mixing in reservoir rocks using 3-D PET imaging

2016 ◽  
Vol 796 ◽  
pp. 558-587 ◽  
Author(s):  
Ronny Pini ◽  
Nicholas T. Vandehey ◽  
Jennifer Druhan ◽  
James P. O’Neil ◽  
Sally M. Benson
Keyword(s):  
Imaging Techniques ◽  
Three Dimensional ◽  
Tracer Tests ◽  
Spatial Arrangement ◽  
Small Scale ◽  
Local Dispersion ◽  
Advection Dispersion ◽  
Driving Mechanisms ◽  
Positron Emission ◽  
Longitudinal Dispersivity

We report results of an experimental investigation into the effects of small-scale (mm–cm) heterogeneities on solute spreading and mixing in a Berea sandstone core. Pulse-tracer tests have been carried out in the Péclet number regime $Pe=6{-}40$ and are supplemented by a unique combination of two imaging techniques. X-ray computed tomography (CT) is used to quantify subcore-scale heterogeneities in terms of permeability contrasts at a spatial resolution of approximately $10~\text{mm}^{3}$, while [11C] positron emission tomography (PET) is applied to image the spatial and temporal evolution of the full tracer plume non-invasively. To account for both advective spreading and local (Fickian) mixing as driving mechanisms for solute transport, a streamtube model is applied that is based on the one-dimensional advection–dispersion equation. We refer to our modelling approach as semideterministic, because the spatial arrangement of the streamtubes and the corresponding solute travel times are known from the measured rock’s permeability map, which required only small adjustments to match the measured tracer breakthrough curve. The model reproduces the three-dimensional PET measurements accurately by capturing the larger-scale tracer plume deformation as well as subcore-scale mixing, while confirming negligible transverse dispersion over the scale of the experiment. We suggest that the obtained longitudinal dispersivity ($0.10\pm 0.02$  cm) is rock rather than sample specific, because of the ability of the model to decouple subcore-scale permeability heterogeneity effects from those of local dispersion. As such, the approach presented here proves to be very valuable, if not necessary, in the context of reservoir core analyses, because rock samples can rarely be regarded as ‘uniformly heterogeneous’.

scholarly journals MaioRegen Osteochondral Substitute for the Treatment of Knee Defects: A Systematic Review of the Literature

2019 ◽  
Vol 8 (6) ◽  
pp. 783 ◽  
Author(s):  
Riccardo D’Ambrosi ◽  
Federico Valli ◽  
Paola De Luca ◽  
Nicola Ursino ◽  
Federico Usuelli
Keyword(s):  
Systematic Review ◽  
Clinical Improvement ◽  
Three Dimensional ◽  
Lesion Size ◽  
Review Of The Literature ◽  
Level Of Evidence ◽  
Significant Clinical Improvement ◽  
Almost All ◽  
Femoral Condyles

Background: This study aims to investigate the clinical and radiological efficacy of three-dimensional acellular scaffolds (MaioRegen) in restoring osteochondral knee defects. Methods: MEDLINE, Scopus, CINAHL, Embase, and Cochrane Databases were searched for articles in which patients were treated with MaioRegen for osteochondral knee defects. Results: A total of 471 patients were included in the study (mean age 34.07 ± 5.28 years). The treatment involved 500 lesions divided as follows: 202 (40.4%) medial femoral condyles, 107 (21.4%) lateral femoral condyles, 28 (5.6%) tibial plateaus, 46 (9.2%) trochleas, 74 (14.8%) patellas, and 43 (8.6%) unspecified femoral condyles. Mean lesion size was 3.6 ± 0.85 cm2. Only four studies reported a follow-up longer than 24 months. Significant clinical improvement has been reported in almost all studies with further improvement up to 5 years after surgery. A total of 59 complications were reported of which 52 (11.1%) experienced minor complications and 7 (1.48%) major complications. A total of 16 (3.39%) failures were reported. Conclusion: This systematic review describes the current available evidence for the treatment of osteochondral knee defects with MaioRegen Osteochondral substitute reporting promising satisfactory and reliable results at mid-term follow-up. A low rate of complications and failure was reported, confirming the safety of this scaffold. Considering the low level of evidence of the study included in the review, this data does not support the superiority of the Maioregen in terms of clinical improvement at follow-up compared to conservative treatment or other cartilage techniques.

Effects of an opioid receptor agonist and antagonist on cytokine-stimulated canine articular chondrocytes in three-dimensional culture

2002 ◽  
Vol 15 (02) ◽  
pp. 72-77
Author(s):  
J. L. Cook ◽  
J. R. Dodam ◽  
J. M. Kreeger ◽  
J. L. Tomlinson ◽  
K. Kuroki ◽  
...  
Keyword(s):  
Opioid Receptor ◽  
Receptor Agonist ◽  
Articular Chondrocytes ◽  
Interleukin 1 ◽  
Three Dimensional ◽  
Culture Liquid ◽  
Pge2 Production ◽  
Opioid Receptor Agonist ◽  
Agonist And Antagonist ◽  
Μ Opioid Receptor

SummaryThe objective of this study was to evaluate the effects of [D-Ala2, Nme-Phe4, Gly5-ol] enkephalin (DAMGO), a μ-opioid receptor agonist, and β-funaltrexamine (β-FNA), a μ-opioid receptor antagonist, on the biosynthetic capabilities of canine chondrocytes cultured in the presence of interleukin-1 β (IL-1 β). Articular chondrocytes were harvested from the humeral heads of three adult dogs and cultured in a three-dimensional (3-D) gel medium made from low-melting agarose and cell culture medium. Chondrocytes in 3-D culture were exposed to IL-1 β (0 or 20 ng/ml), DAMGO (0,0.1,1.0, or 10 μM), and β-FNA (0 or 10 μM) by addition to the liquid media in all possible combinations. On days five and 15 of 3-D culture, liquid medium samples were harvested for subsequent analysis of glycosaminogly- can (GAG), prostaglandin E2 (PGE2) and matrix metalloprotease-3 (MMP-3) content. On the same days, gel plugs were also harvested and evaluated for GAG content.Incubation with IL-1 β decreased the amount of GAG in the gel plugs and caused an increase in PGE2 production on days five and 15 of 3-D culture. Treatment with DAMGO or β-FNA did not significantly modulate PGE2 production, MMP-3 production, GAG loss to the medium or GAG content of the gel plugs on either day five or 15 of 3-D culture in the presence or absence of IL-1 β. We concluded that DAMGO and β-FNA had neither protective nor detrimental effects on the biosynthetic capabilities of chondrocytes in the presence or absence of IL-1 β.

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