Brain Vessels Research Articles

The Effects of Improper Communication on the Brain, Heart, and Blood Vessels

People interact through words, music, attitudes, or images, making to think about them. Human energy transfer to each other modulates the individual response interacting. Info perception and processing generate personal mental and physical activity. Social norms of people interaction facilitate individual well-being; deviation from normal limits for people collaboration represents the point start of various disorders, according to the magnitude of unsafe interaction, time exposure, and vulnerability of the intended recipient.

Lysosomal dysfunction induced cytosolic vacuolation and increased intracellular amyloid-beta 42 (Aβ42) in human brain endothelial cells (HBEC-5i)

Lysosome is a primary degradative organelle and is crucial in cellular homeostasis. A reduction in its function due to ageing has been associated with the development of Alzheimer's disease (AD), a common neurodegenerative disorder characterised by the deposition of neurotoxic amyloid plaque in the brain and cerebral vessel walls. The breakdown of the blood-brain barrier (BBB) plays a vital role in the pathogenesis of AD. However, the impact of lysosomal dysfunction on brain endothelial cells, the key component of the BBB, in the disease progression is yet to be fully understood. In this study, human brain endothelial cells (HBEC-5i) were exposed to a lysosomotropic compound, chloroquine (CQ) for 24 h. Cell viability was assessed with the 3-(4,5-dimethylthiazol-2-yl)− 2,5-diphenyltetrazolium bromide (MTT) assay to determine the inhibitory concentration (IC) at IC10 (17.5 µM), IC25 (70.5 µM), and IC50 (125 µM). The morphological changes observed include vacuoles arrested in the cytosols and cell shrinkage that were more prominent at IC25 and IC50. Lysosomal dysfunction was evaluated by measuring the lysosomal-associated membrane protein-1 (LAMP-1) and microtubule-associated protein light chain 3-II (LC3-II) using the capillary-based immunoassay. LC3-II was significantly increased at IC25 and IC50 (p < 0.05 and p < 0.001, respectively). The concentration of intracellular and extracellular Aβ42 was quantitated using the enzyme-linked immunosorbent assay, which demonstrated a significant increase (p < 0.05) in intracellular Aβ42 at IC25. This study showed that perturbation of lysosomal function impairs autophagy that leads to intracellular increment of Aβ, indicating the important roles of lysosomes in endothelial cells homeostasis and disease progression.

Therapeutic effect of α7 nicotinic receptor activation after ischemic stroke in rats

Nicotinic acetylcholine α7 receptors (α7 nAChRs) have a well-known modulator effect in neuroinflammation. Yet, the therapeutical effect of α7 nAChRs activation after stroke has been scarcely evaluated to date. The role of α7 nAChRs activation with PHA 568487 on inflammation after brain ischemia was assessed with positron emission tomography (PET) using [18F]DPA-714 and [18F]BR-351 radiotracers after transient middle cerebral artery occlusion (MCAO) in rats. The assessment of brain oedema, blood brain barrier (BBB) disruption and neurofunctional progression after treatment was evaluated with T2 weighted and dynamic contrast-enhanced magnetic resonance imaging (T2 W and DCE-MRI) and neurological evaluation. The activation of α7 nAChRs resulted in a decrease of ischemic lesion, midline displacement and cell neurodegeneration from days 3 to 7 after ischemia. Besides, the treatment with PHA 568487 improved the neurofunctional outcome. Treated ischemic rats showed a significant [18F]DPA-714-PET uptake reduction at day 7 together with a decrease of activated microglia/infiltrated macrophages. Likewise, the activation of α7 receptors displayed an increase of [18F]BR-351-PET signal in ischemic cortical regions, which resulted from the overactivation of MMP-2. Finally, the treatment with PHA 568487 showed a protective effect on BBB disruption and blood brain vessel integrity after cerebral ischemia.

FREQUENCY OF METABOLIC SYNDROME IN PATIENTS WITH SYSTEMIC LUPUS ERYTHEMATOSUS PRESENTING AT A PUBLIC SECTOR TERTIARY CARE HOSPITAL OF LAHORE: A CROSS- SECTIONAL STUDY

Background and Objective: Metabolic syndrome is characterized by central obesity, deranged lipid profile, high blood pressure and abnormally high levels of blood sugar. It is an independent risk factor for cardiovascular disease. Systemic Lupus Erythematosus (SLE) is an autoimmune disease that can affect joints, skin, brain, lungs, kidneys, and blood vessels. The extent to which metabolic syndrome is frequent in our population is less known. The objective of this study was to assess the frequency of metabolic syndrome amongst SLE patients. Methods: This cross-sectional study was undertaken in a public sector tertiary care hospital of Lahore from February 2021 through August 2021, including 110 confirmed SLE cases. After institutional approval and taking an informed consent, blood pressure, fasting and random blood sugar levels and fasting lipid profile were measured. Central obesity was assessed using waist circumference. Data were transferred to SPSS 21 for descriptive and inferential analyses. Frequencies were determined using numbers and percentages. Results: Of 110 SLE patients, 14 (12.3%) were males and 96 (87.7%) were females. Mean age of SLE patients was 42.9± 9.9 years. Mean BMI was 28.7±4.7 kg/m2. The frequency of metabolic syndrome in studied SLE patients was 37/110 (33.6%). Conclusion: Systemic lupus erythematosus patients had abnormally high serum triglyceride and cholesterol levels, diabetes mellitus, central obesity, high levels of fasting plasma glucose and hypertension. Therefore, one-third of SLE patients may have metabolic syndrome in our population.

Noninvasive Brain Stimulation for Neurorehabilitation in Post-Stroke Patients.

Characterized by high morbidity, mortality, and disability, stroke usually causes symptoms of cerebral hypoxia due to a sudden blockage or rupture of brain vessels, and it seriously threatens human life and health. Rehabilitation is the essential treatment for post-stroke patients suffering from functional impairments, through which hemiparesis, aphasia, dysphagia, unilateral neglect, depression, and cognitive dysfunction can be restored to various degrees. Noninvasive brain stimulation (NIBS) is a popular neuromodulatory technology of rehabilitation focusing on the local cerebral cortex, which can improve clinical functions by regulating the excitability of corresponding neurons. Increasing evidence has been obtained from the clinical application of NIBS, especially repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS). However, without a standardized protocol, existing studies on NIBS show a wide variation in terms of stimulation site, frequency, intensity, dosage, and other parameters. Its application for neurorehabilitation in post-stroke patients is still limited. With advances in neuronavigation technologies, functional near-infrared spectroscopy, and functional MRI, specific brain regions can be precisely located for stimulation. On the basis of our further understanding on neural circuits, neuromodulation in post-stroke rehabilitation has also evolved from single-target stimulation to co-stimulation of two or more targets, even circuits and the network. The present study aims to review the findings of current research, discuss future directions of NIBS application, and finally promote the use of NIBS in post-stroke rehabilitation.

Reversible Cerebral Vasoconstriction Syndrome Treated by Continuous Intravenous Milrinone

Reversible cerebral vasoconstriction syndrome (RCVS) is characterized by severe headaches, with or without other acute neurological symptoms, and diffuse segmental constriction of cerebral arteries that resolves spontaneously within 3 months.[1] It can occur spontaneously, especially in middle-aged women[1]; at least half the cases occur after exposure to vasoactive drugs or post-partum. This syndrome is often associated with a favorable outcome in 95% of cases.[1] However, the prognosis of RCVS is especially determined by stroke occurrence. Its management is inspired by what is applied in aneurysmal subarachnoid hemorrhage (aSAH), whose main complication is vasospasm and delayed cerebral ischemia (DCI). Although the physiopathology of RCVS is unclear, it appears to be distinct from aSAH. Indeed, the vasoconstriction in RCVS may be dependent on the activity and sensitivity of vascular receptors, which can lead to a more systemic effect on all brain vessels, as opposed to being dependent on the vasospasm induced by local clot lysis, as has been suggested in aSAH.[2] As cerebral arteries are densely innervated, the release of norepinephrine or neuropeptide Y from the sympathetic nerve endings may cause vasoconstrictions.[3] Angiographically, SAH-induced vasospasm is more commonly long-segmental and mainly around the bleeding focus, compared with the multiple, short-segmental, and diffuse changes seen in RCVS.[4] However, by analogy, RCVS is treated by nimodipine, and in some rare cases, the use of milrinone might be considered.[3]

Blood-brain barrier function in response to SARS-CoV-2 and its spike protein.

The typical manifestation of coronavirus 2 (CoV-2) infection is a severe acute respiratory syndrome (SARS) accompanied by pneumonia (COVID-19). However, SARS-CoV-2 can also affect t he b rain, c ausing c hronic n eurological s ymptoms, variously known as long, post, post-acute, or persistent COVID-19 condition, and affecting up to 40% of patients. The symptoms (fatigue, dizziness, headache, sleep disorders, malaise, disturbances of memory and mood) usually are mild and resolve spontaneously. However, some patients develop acute and fatal complications, including stroke or encephalopathy. Damage to the brain vessels mediated by the coronavirus spike protein (S-protein) and overactive immune responses have been identified as leading causes of this condition. However, the molecular mechanism by which the virus affects the brain still needs to be fully delineated. In this review article, we focus on interactions between host molecules and S-protein as the mechanism allowing the transit of SARS-CoV-2 through the blood-brain barrier to reach the brain structures. In addition, we discuss the impact of S-protein mutations and the involvement of other cellular factors conditioning the pathophysiology of SARS-CoV-2 infection. Finally, we review current and future COVID-19 treatment options.

The Role of Heart Rate Variability (HRV) in Different Hypertensive Syndromes

Cardiac innervation by the parasympathetic nervous system (PNS) and the sympathetic nervous system (SNS) modulates the heart rate (HR) (chronotropic activity) and the contraction of the cardiac muscle (inotropic activity). The peripheral vasculature is controlled only by the SNS, which is responsible for peripheral vascular resistance. This also mediates the baroreceptor reflex (BR), which in turn mediates blood pressure (BP). Hypertension (HTN) and the autonomic nervous system (ANS) are closely related, such that derangements can lead to vasomotor impairments and several comorbidities, including obesity, hypertension, resistant hypertension, and chronic kidney disease. Autonomic dysfunction is also associated with functional and structural changes in target organs (heart, brain, kidneys, and blood vessels), increasing cardiovascular risk. Heart rate variability (HRV) is a method of assessing cardiac autonomic modulation. This tool has been used for clinical evaluation and to address the effect of therapeutic interventions. The present review aims (a) to approach the heart rate (HR) as a CV risk factor in hypertensive patients; (b) to analyze the heart rate variability (HRV) as a "tool" to estimate the individual risk stratum for Pre-HTN (P-HTN), Controlled-HTN (C-HTN), Resistant and Refractory HTN (R-HTN and Rf-HTN, respectively), and hypertensive patients with chronic renal disease (HTN+CKD).

Induced Inflammatory and Oxidative Markers in Cerebral Microvasculature by Mentally Depressive Stress.

Cerebrovascular disease (CVD) is recognized as the leading cause of permanent disability worldwide. Depressive disorders are associated with increased incidence of CVD. The goal of this study was to establish a chronic restraint stress (CRS) model for mice and examine the effect of stress on cerebrovascular inflammation and oxidative stress responses. A total of forty 6-week-old male C57BL/6J mice were randomly divided into the CRS and control groups. In the CRS group (n = 20), mice were placed in a well-ventilated Plexiglas tube for 6 hours per day for 28 consecutive days. On day 29, open field tests (OFT) and sucrose preference tests (SPT) were performed to assess depressive-like behaviors for the two groups (n = 10/group). Macrophage infiltration into the brain tissue upon stress was analyzed by measuring expression of macrophage marker (CD68) with immunofluorescence in both the CRS and control groups (n = 10/group). Cerebral microvasculature was isolated from the CRS and controls (n = 10/group). mRNA and protein expressions of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), interleukin-6 (IL-6), vascular cell adhesion molecule-1 (VCAM-1), and macrophage chemoattractant protein-1 (MCP-1) in the brain vessels were measured by real-time PCR and Western blot (n = 10/group). Reactive oxygen species (ROS), hydrogen peroxide (H2O2), and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX) activities were quantified by ELISA to study the oxidative profile of the brain vessels (n = 10/group). Additionally, mRNA and protein expressions of NOX subunits (gp91phox, p47phox, p67phox, and p22phox) in the cerebrovascular endothelium were analyzed by real-time PCR and Western blot (n = 10/group). CRS decreased the total distances (p < 0.05) and the time spent in the center zone in OFT (p < 0.001) and sucrose preference test ratio in SPT (p < 0.01). Positive ratio of CD68+ was increased with CRS in the entire region of the brain (p < 0.001), reflecting increased macrophage infiltration. CRS increased the expression of inflammatory factors and oxidative stress in the cerebral microvasculature, including TNF-α (p < 0.001), IL-1β (p < 0.05), IL-6 (p < 0.05), VCAM-1 (p < 0.01), MCP-1 (p < 0.01), ROS (p < 0.001), and H2O2 (p < 0.001). NADPH oxidase (NOX) was activated by CRS (p < 0.01), and mRNA and protein expressions of NOX subunits (gp91phox, p47phox, p67phox, and p22phox) in brain microvasculature were found to be increased. To our knowledge, this is the first study to demonstrate that CRS induces depressive stress and causes inflammatory and oxidative stress responses in the brain microvasculature.

Cerebral chronic hypoperfusion in mice causes premature aging of the cerebrovasculature

Chronic cerebral hypoperfusion (CCH) is the main characteristic of an aged brain showing cerebrovascular alterations. Our previous study that the morphological changes in the pial arteries accompany a decrease in the cerebral blood flow in aged mouse brains, and it raises the question of whether artificial CCH can induce the same changes in brain vessel morphology. Here, we examined the effect of CCH on cerebrovascular morphology. Using a microcoil-induced chronic cerebral hypoperfusion (MCH) model, we induced CCH for 8 and 12 weeks. The cerebrovasculature morphology was evaluated using three-dimensional vessel analysis and compared with that of aging mice. We found the morphological changes in brain vessels of MCH mice, indicating that the CCH can induce cerebrovascular alteration. However, the changes in brain vessel morphology in the MCH mice were different in detail from those in the aging mice. Aging mice showed an increase in vessel tortuosity and thinned string vessels; MCH mice mainly showed thinned string vessels. This suggests that CCH may be a cause of age-related cerebrovascular alterations.

Enhancing the depth perception of DSA images with 2D-3D registration.

Today, cerebrovascular disease has become an important health hazard. Therefore, it is necessary to perform a more accurate and less time-consuming registration of preoperative three-dimensional (3D) images and intraoperative two-dimensional (2D) projection images which is very important for conducting cerebrovascular disease interventions. The 2D-3D registration method proposed in this study is designed to solve the problems of long registration time and large registration errors in 3D computed tomography angiography (CTA) images and 2D digital subtraction angiography (DSA) images. To make a more comprehensive and active diagnosis, treatment and surgery plan for patients with cerebrovascular diseases, we propose a weighted similarity measure function, the normalized mutual information-gradient difference (NMG), which can evaluate the 2D-3D registration results. Then, using a multi-resolution fusion optimization strategy, the multi-resolution fused regular step gradient descent optimization (MR-RSGD) method is presented to attain the optimal value of the registration results in the process of the optimization algorithm. In this study, we adopt two datasets of the brain vessels to validate and obtain similarity metric values which are 0.0037 and 0.0003, respectively. Using the registration method proposed in this study, the time taken for the experiment was calculated to be 56.55s and 50.8070s, respectively, for the two sets of data. The results show that the registration methods proposed in this study are both better than the Normalized Mutual (NM) and Normalized Mutual Information (NMI). The experimental results in this study show that in the 2D-3D registration process, to evaluate the registration results more accurately, we can use the similarity metric function containing the image gray information and spatial information. To improve the efficiency of the registration process, we can choose the algorithm with gradient optimization strategy. Our method has great potential to be applied in practical interventional treatment for intuitive 3D navigation.

Abstract TP129: Increased Levels Of Matrix Metalloproteinases-induced BBB Dysfunction May Be Responsible For Increased Post-sich Hematoma Growth In Nicotine-exposed Rats.

Spontaneous intracerebral hemorrhage (sICH) is the deadliest type of stroke, accounting for as high as 28% of all strokes. Tobacco use is one of the major risk factors of sICH, and it also worsens outcomes following sICH. In our earlier study, we observed that nicotine exposure increases TNFα levels in brain vessels, impairs BBB integrity, and increases post-sICH hematoma volume in a TNFα-dependent manner compared to saline-exposed controls. Earlier studies have demonstrated interactions between MMPs and TNFα. Increased levels of matrix metalloproteinases (MMPs) have been found in sICH patients and nicotine-exposed individuals. MMPs are involved in BBB breakdown, edema formation, hematoma expansion, and neuronal loss that follow hematoma development after sICH. In the present study, we tested the hypothesis that nicotine exposure-induced increase in TNFα is responsible for increased post-sICH hematoma volume in a MMP-dependent manner. To test our hypothesis, young male and female rats were exposed to chronic nicotine treatment for 2-3 weeks using osmotic pumps containing either saline or nicotine (4.5 mg/kg/day). Levels of MMPs (2, 3, 9, and 12) and GAPDH were evaluated in brain homogenates using Western blot. Nicotine-treated female rats showed a 37% (100±7 vs. 137±10, p&lt;0.05), 144% (100±18 vs. 244±16, p&lt;0.01), 29% (100±7 vs. 129±9, p&lt;0.05), 22% (100±6 vs. 122±6, p&lt;0.05), and 24% (100±6 vs. 124±7, p&lt;0.05) increase in levels of pro and cleaved forms of MMP-3, cleaved form of MMP-9, pro and cleaved forms of MMP-12, respectively, compared to saline-treated female rats. We are in the process of evaluating levels of MMPs in male samples. Considering the role of MMP-9 in BBB integrity, using both TNFα and MMP-9 inhibitors, we are also in the process of evaluating if TNFα increases post-sICH hematoma growth in nicotine-exposed rats via increased levels of MMP-9. The results so far imply that increased TNFα levels in nicotine-exposed rats may be responsible for increased post-sICH hematoma growth in a MMP-dependent manner. Support: James Esther King Biomedical Research Grant 9JK08 and PK is a recipient of the Lois Pope Neuroscience Summer Research Fellowship.

Brain and Blood Vessel Imaging for Ischemic Stroke in Patients with Covid-19—Data from the Literature and Clinical Cases

Abstract This study explores the relationship between patients diagnosed with ischemic stroke and SARS-CoV-2 infection. The focus is on the role of neuroimaging in confirming the diagnosis of ischemic stroke and guiding patient care. The COVID-19 pandemic has posed challenges in di-agnosing and treating patients with neurological pathologies due to the time-sensitive nature of stroke management. The objective of this study was to analyze cases of patients with ischemic stroke and SARS-CoV-2 infection, emphasizing the importance of neuroimaging in confirming the diagnosis. The study aimed to provide insights into the characteristics and clinical manifestations of these patients, contributing to our understanding of the neurological impacts of COVID-19. A retrospective analysis of hospitalized patients with a diagnosis of ischemic stroke and SARS-CoV-2 infection was conducted. The study focused on five representative cases, including patient demographics, medical histories, clinical symptoms, and imaging findings. Brain CT and MRI scans were performed to confirm the diagnosis of ischemic stroke. Among the 120 cases analyzed, 5 representative cases are presented. These cases include patients of varying age and gender with concurrent neurological pathologies and COVID-19 infections. Neuroimaging, such as CT and MRI, confirmed the diagnosis of ischemic stroke in these patients. Patients with SARS-CoV-2 in-fection and ischemic stroke often present with moderate to severe strokes, frequently involving large vessel obstructions. Neuroimaging plays a critical role in diagnosing and characterizing ischemic stroke in these patients. Identifying thrombotic angiopathy, vascular injury, and im-paired vascular autoregulation are essential for prompt diagnosis and treatment. This study emphasizes the significance of neuroimaging in managing patients with both COVID-19 and neurological pathologies, contributing to our understanding of the neurological implications of COVID-19.

Abstract WP225: Rapid Complement Activation Induced By Acute Hyperglycemia Worsens Ischemic Stroke Outcome

Background: Acute hyperglycemia, which occurs in over 40% of ischemic stroke patients regardless of pre-existing diabetes, increases brain edema, hemorrhagic transformation (HT) and worsens stroke outcome. Understanding the mechanisms of hyperglycemia-exacerbated stroke injury will be vital for developing novel treatments. Here we identify systemic complement activation as a novel contributor to hyperglycemic-exacerbated damage in rodent stroke. Method: Male C57/BL6 mice (10-11 weeks) were subjected to middle cerebral artery occlusion (MCAO) for 30 min, followed by reperfusion to mimic ischemic stroke. Acute hyperglycemia was induced by glucose injection 10 min before MCAO. To assess the effect of hyperglycemia on stroke outcomes, mice were sacrificed at 4.5 and 24 hr post-stroke to analyze brain edema, blood-brain barrier (BBB) leakage, and HT; or allowed to survive 14 days to examine mortality rate, neurological deficit, and motor-sensory dysfunction using the horizontal rotating beam test. Complement activation was evaluated at 1, 2, 4.5 hr post-stroke. To inhibit C3 activation, the targeted complement inhibitor CR2-Crry fusion protein, or PBS control, was injected via femoral vein 15 min after reperfusion. Result: Hyperglycemia worsens stroke outcomes in our mouse model, with rapid increased BBB leakage (p&lt;0.0001), brain swelling (p&lt;0.001) and HT at (p&lt;0.0001) 4.5 and 24 hr after stroke compared to normoglycemia; and poorer prognosis including higher mortality (100% VS 25%, p=0.0008), body weight loss, and impaired behavioral performance by day 14. Interestingly, acute hyperglycemia rapidly increased plasma complement C3 levels at 1 and 2 hr after stroke (p&lt;0.01 compared to normoglycemic mice), accompanied by activation of C3 in ischemic brain vessels as indicated by elevated levels of vascular C3d. Vascular C3d colocalized with IgM/IgG, suggesting the involvement of classical pathway in C3 activation. Notably, activated C3 levels positively correlated with brain swelling and HT (p&lt;0.01). Inhibition of C3 by CR2-Crry markedly reduced brain swelling (p&lt;0.05) and HT in hyperglycemic stroke. Conclusion: Rapid activation of complement C3 by acute hyperglycemia may be an important contributor to BBB leakage, brain swelling and HT.

An agonistic anti-Tie2 antibody suppresses the normal-to-tumor vascular transition in the glioblastoma invasion zone

Tumor progression is intimately associated with the vasculature, as tumor proliferation induces angiogenesis and tumor cells metastasize to distant organs via blood vessels. However, whether tumor invasion is associated with blood vessels remains unknown. As glioblastoma (GBM) is featured by aggressive invasion and vascular abnormalities, we characterized the onset of vascular remodeling in the diffuse tumor infiltrating zone by establishing new spontaneous GBM models with robust invasion capacity. Normal brain vessels underwent a gradual transition to severely impaired tumor vessels at the GBM periphery over several days. Increasing vasodilation from the tumor periphery to the tumor core was also found in human GBM. The levels of vascular endothelial growth factor (VEGF) and VEGF receptor 2 (VEGFR2) showed a spatial correlation with the extent of vascular abnormalities spanning the tumor-invading zone. Blockade of VEGFR2 suppressed vascular remodeling at the tumor periphery, confirming the role of VEGF-VEGFR2 signaling in the invasion-associated vascular transition. As angiopoietin-2 (ANGPT2) was expressed in only a portion of the central tumor vessels, we developed a ligand-independent tunica interna endothelial cell kinase 2 (Tie2)-activating antibody that can result in Tie2 phosphorylation in vivo. This agonistic anti-Tie2 antibody effectively normalized the vasculature in both the tumor periphery and tumor center, similar to the effects of VEGFR2 blockade. Mechanistically, this antibody-based Tie2 activation induced VE-PTP-mediated VEGFR2 dephosphorylation in vivo. Thus, our study reveals that the normal-to-tumor vascular transition is spatiotemporally associated with GBM invasion and may be controlled by Tie2 activation via a novel mechanism of action.

Multiple Brain Tumor Classification with Dense CNN Architecture Using Brain MRI Images

Brain MR images are the most suitable method for detecting chronic nerve diseases such as brain tumors, strokes, dementia, and multiple sclerosis. They are also used as the most sensitive method in evaluating diseases of the pituitary gland, brain vessels, eye, and inner ear organs. Many medical image analysis methods based on deep learning techniques have been proposed for health monitoring and diagnosis from brain MRI images. CNNs (Convolutional Neural Networks) are a sub-branch of deep learning and are often used to analyze visual information. Common uses include image and video recognition, suggestive systems, image classification, medical image analysis, and natural language processing. In this study, a new modular deep learning model was created to retain the existing advantages of known transfer learning methods (DenseNet, VGG16, and basic CNN architectures) in the classification process of MR images and eliminate their disadvantages. Open-source brain tumor images taken from the Kaggle database were used. For the training of the model, two types of splitting were utilized. First, 80% of the MRI image dataset was used in the training phase and 20% in the testing phase. Secondly, 10-fold cross-validation was used. When the proposed deep learning model and other known transfer learning methods were tested on the same MRI dataset, an improvement in classification performance was obtained, but an increase in processing time was observed.

Nematode-Induced Growth Factors Related to Angiogenesis in Autoimmune Disease Attenuation.

Accumulating data suggest an important role of growth factors in autoimmune diseases and parasitic nematode infections. Nematodes are used in clinical studies of autoimmune diseases and parasite-derived molecules are widely studied for their therapeutic potential in various types of disorders. However, the effect of nematode infection on growth factors in autoimmune disorders has not been studied. The objective of this study was to evaluate the influence of infection with the intestinal nematode Heligmosomoides polygyrus in murine autoimmune models on the production of growth factors. Here, the level of a variety of growth factors related mainly to angiogenesis was evaluated by protein array in the intestinal mucosa of C57BL/6 dextran sodium sulfate-induced colitic mice and in cerebral spinal fluid of experimental autoimmune encephalomyelitis (EAE) mice infected with nematodes. In addition, vessel formation was evaluated in the brains of EAE mice infected with H. polygyrus. A significant influence of nematode infection on the level of angiogenic factors was observed. Parasitic infection of colitic mice resulted in upregulation of mucosal AREG, EGF, FGF-2, and IGFBP-3 in the intestine of the host and better adaptation (infectivity). In EAE mice, infection increased the level of FGF-2 and FGF-7 in CSF. In addition, remodeling of brain vessels was observed, with a higher density of long vessels. Nematode-derived factors are promising tools to fight autoimmune diseases and to study angiogenesis.

Dynamic MRI of the Mesenchymal Stem Cells Distribution during Intravenous Transplantation in a Rat Model of Ischemic Stroke.

Systemic transplantation of mesenchymal stem cells (MSCs) is a promising approach for the treatment of ischemia-associated disorders, including stroke. However, exact mechanisms underlying its beneficial effects are still debated. In this respect, studies of the transplanted cells distribution and homing are indispensable. We proposed an MRI protocol which allowed us to estimate the dynamic distribution of single superparamagnetic iron oxide labeled MSCs in live ischemic rat brain during intravenous transplantation after the transient middle cerebral artery occlusion. Additionally, we evaluated therapeutic efficacy of cell therapy in this rat stroke model. According to the dynamic MRI data, limited numbers of MSCs accumulated diffusely in the brain vessels starting at the 7th minute from the onset of infusion, reached its maximum by 29 min, and gradually eliminated from cerebral circulation during 24 h. Despite low numbers of cells entering brain blood flow and their short-term engraftment, MSCs transplantation induced long lasting improvement of the neurological deficit, but without acceleration of the stroke volume reduction compared to the control animals during 14 post-transplantation days. Taken together, these findings indicate that MSCs convey their positive action by triggering certain paracrine mechanisms or cell-cell interactions or invoking direct long-lasting effects on brain vessels.

Generation of Human Blood Vessel Organoids from Pluripotent Stem Cells.

An organoid is defined as an engineered multicellular in vitro tissue that mimics its corresponding in vivo organ such that it can be used to study defined aspects of that organ in a tissue culture dish. The breadth and application of human pluripotent stem cell (hPSC)-derived organoid research have advanced significantly to include the brain, retina, tear duct, heart, lung, intestine, pancreas, kidney, and blood vessels, among several other tissues. The development of methods for the generation of human microvessels, specifically, has opened the way for modeling human blood vessel development and disease in vitro and for the testing and analysis of new drugs or tissue tropism in virus infections, including SARS-CoV-2. Complex and lengthy protocols lacking visual guidance hamper the reproducibility of many stem cell-derived organoids. Additionally, the inherent stochasticity of organoid formation processes and self-organization necessitates the generation of optical protocols to advance the understanding of cell fate acquisition and programming. Here, a visually guided protocol is presented for the generation of 3D human blood vessel organoids (BVOs) engineered from hPSCs. Presenting a continuous basement membrane, vascular endothelial cells, and organized articulation with mural cells, BVOs exhibit the functional, morphological, and molecular features of human microvasculature. BVO formation is initiated through aggregate formation, followed by mesoderm and vascular induction. Vascular maturation and network formation are initiated and supported by embedding aggregates in a 3D collagen and solubilized basement membrane matrix. Human vessel networks form within 2-3 weeks and can be further grown in scalable culture systems. Importantly, BVOs transplanted into immunocompromised mice anastomose with the endogenous mouse circulation and specify into functional arteries, veins, and arterioles. The present visually guided protocol will advance human organoid research, particularly in relation to blood vessels in normal development, tissue vascularization, and disease.

The The multifaceted functions of mineralocorticoid receptor in cardiometabolic disease

Cardiometabolic diseases (CMDs), which cause 31% of all global deaths, are one of the greatest public health challenges. Mineralocorticoid receptor (MR), as a key nuclear transcription factor, is an important drug target for the treatment of CMDs. It is known that MR is expressed in almost all tissues and organs involved in cardiovascular homeostasis, including immune tissue, adipose tissue, brain, heart, kidney, and blood vessels. In the pathophysiology of CMDs, MR exerts different functions in different tissues and cells. This review summarizes the roles of MR in various cell types and discusses the molecular mechanisms through which MR exerts it functions in CMDs.