Vascular System Research Articles

Angpt1 binding to Tie1 regulates the signaling required for lymphatic vessel development in zebrafish.

Development of the vascular system is regulated by multiple signaling pathways mediated by receptor tyrosine kinases (RTKs). Among them, angiopoietin (Ang)/Tie signaling regulates lymphatic and blood vessel development in mammals. Of the two Tie receptors, Tie2 is well known as a key mediator of Ang/Tie signaling, but unexpectedly, recent studies reveal that the Tie2 locus has been lost in many vertebrate species, while the Tie1 gene is more commonly present. However, Tie1-driven signaling pathways, including ligands and cellular functions, are not well understood. Here, we performed comprehensive mutant analyses of angiopoietins and Tie receptors in zebrafish and found that only angpt1 and tie1 mutants show defects in trunk lymphatic vessel development. Among zebrafish angiopoietins, only Angpt1 binds to Tie1 as a ligand. We indirectly monitored Ang1/Tie1 signaling and detected Tie1 activation in sprouting endothelial cells (ECs), where Tie1 inhibits nuclear import of EGFP-Foxo1a. Angpt1/Tie1 signaling functions in EC migration, proliferation, and lymphatic specification during early lymphangiogenesis, at least in part by modulating Vegfc/Vegfr3 signaling. Thus, we show Angpt1/Tie1 signaling to constitute an essential signaling pathway for lymphatic development in zebrafish.

Progressive Pulmonary Tuberculosis – Progress Beyond the Walls

Tuberculosis is caused by Mycobacterium tuberculosis. If the treatment is inadequate or if host defenses are impaired, the apical lesion in primary tuberculosis expands into adjacent lung tissues and may spread via airways, lymphatic channels, or the vascular system. It may also circulate back to the lung and cause miliary pulmonary disease. Systemic miliary tuberculosis occurs when bacteria disseminate through the systemic arterial system to involve any organ. In the present study, we discuss five such cases of systemic miliary tuberculosis wherein the deceased succumbed to the illness.

Plasma Biomarkers for Hypertension-Mediated Organ Damage Detection: A Narrative Review

Hypertension (HT) is a disease that poses a serious threat to human health, mediating organ damage such as the cardiovascular (CV) system, kidneys, central nervous system (CNS), and retinae, ultimately increasing the risk of death due to damage to the entire vascular system. Thus, the widespread prevalence of hypertension brings enormous health problems and socioeconomic burdens worldwide. The goal of hypertension management is to prevent the risk of hypertension-mediated organ damage and excess mortality of cardiovascular diseases. To achieve this goal, hypertension guidelines recommend accurate monitoring of blood pressure and assessment of associated target organ damage. Early identification of organ damage mediated by hypertension is therefore crucial. Plasma biomarkers as a non-invasive test can help identify patients with organ damage mediated by hypertension who will benefit from antihypertensive treatment optimization and improved prognosis. In this review, we provide an overview of some currently available, under-researched, potential plasma biomarkers of organ damage mediated by hypertension, looking for biomarkers that can be detected by simple testing to identify hypertensive patients with organ damage, which is of great significance in clinical work. Natriuretic peptides (NPs) can be utilized as a traditional biomarker to detect hypertension-mediated organ damage, especially for heart failure. Nevertheless, we additionally may need to combine two or more plasma biomarkers to monitor organ damage in the early stages of hypertension.

Determinants of bacterial survival and proliferation in blood.

Bloodstream infection is a major public health concern associated with high mortality and high healthcare costs worldwide. Bacteremia can trigger fatal sepsis whose prevention, diagnosis and management have been recognized as a global health priority by the World Health Organization. Additionally, infection control is increasingly threatened by antimicrobial resistance, which is the focus of global action plans in the framework of a One Health response. In-depth knowledge of the infection process is needed to develop efficient preventive and therapeutic measures. The pathogenesis of bloodstream infection is a dynamic process resulting from the invasion of the vascular system by bacteria, which finely regulate their metabolic pathways and virulence factors to overcome the blood immune defenses and proliferate. In this review, we highlight our current understanding of determinants of bacterial survival and proliferation in the bloodstream and discuss their interactions with the molecular and cellular components of blood.

FLT4 causes developmental disorders of the cardiovascular and lymphovascular systems via pleiotropic molecular mechanisms.

Rare, deleterious genetic variants in FLT4 are associated with Tetralogy of Fallot (TOF), the most common cyanotic congenital heart disease (CHD). Distinct genetic variants in FLT4 are also an established cause of Milroy disease, the most prevalent form of primary hereditary lymphoedema. Phenotypic features of these two conditions are non-overlapping, implying pleiotropic cellular mechanisms during development. Here, we show that FLT4 variants identified in TOF patients, when expressed in primary human endothelial cells, cause aggregation of FLT4 protein in the perinuclear endoplasmic reticulum, activating proteostatic and metabolic signalling, whereas lymphoedema-associated FLT4 variants and wildtype FLT4 do not. FLT4 TOF variants display characteristic gene expression profiles in key developmental signalling pathways, revealing a role for FLT4 in cardiogenesis distinct from its role in lymphatic development. Inhibition of proteostatic signalling abrogates these effects, identifying potential avenues for therapeutic intervention. Depletion of flt4 in zebrafish caused cardiac phenotypes of reduced heart size and altered heart looping. These phenotypes were rescued with coinjection of wildtype human FLT4 mRNA, but incompletely or not at all by mRNA harbouring FLT4 TOF variants. Taken together, we identify a pathogenic mechanism for FLT4 variants predisposing to TOF that is distinct from the known dominant negative mechanism of Milroy-causative variants. FLT4 variants give rise to conditions of the two circulatory subdivisions of the vascular system via distinct developmental pleiotropic molecular mechanisms. Proteostatic dysfunction, if confirmed as a mechanism of CHD pathogenesis for other predisposing genes, may identify pathways to therapeutic interventions. Distinguishing mechanistically how variants in FLT4 give rise to CHD may have potential to individualise genetic counselling in affected families.

Lower vascular conductance responses to handgrip exercise are improved following acute antioxidant supplementation in young individuals with post-traumatic stress disorder.

Young individuals with post-traumatic stress disorder (PTSD) display peripheral vascular and autonomic nervous system dysfunction, two factors potentially stemming from a redox imbalance. It is currently unclear if these aforementioned factors, observed at rest, alter peripheral haemodynamic responses to exercise in this population. This study examined haemodynamic responses to handgrip exercise in young individuals with PTSD following acute antioxidant (AO) supplementation. Thirteen young individuals with PTSD (age 23±3years), and 13 age- and sex-matched controls (CTRL) participated in the study. Exercise-induced changes to arm blood flow (BF), mean arterial pressure (MAP) and vascular conductance (VC) were evaluated across two workloads of rhythmic handgrip exercise (3 and 6kg). The PTSD group participated in two visits, consuming either a placebo (PL) or AO prior to their visits. The PTSD group demonstrated significantly lower VC (P=0.04) across all exercise workloads (vs. CTRL), which was significantly improved following AO supplementation. In the PTSD group, AO supplementation improved VC in participants possessing the lowest VC responses to handgrip exercise, with AO supplementation significantly improving VC responses (3 and 6kg: P<0.01) by blunting elevated exercise-induced MAP responses (3kg: P=0.01; 6kg: P<0.01). Lower VC responses during handgrip exercise were improved following AO supplementation in young individuals with PTSD. AO supplementation was associated with a blunting of exercise-induced MAP responses in individuals with PTSD displaying elevated MAP responses. This study revealed that young individuals with PTSD exhibit abnormal, peripherally mediated exercise responses that may be linked to a redox imbalance.

Cross-Seal IDE Trial: Prospective, Multicenter, Single-Arm Study of the Cross-Seal Suture-Mediated Vascular Closure Device System.

An increasing number of interventional procedures require large-sheath technology (>12F) with a favorable outcome with endovascular rather than open surgical access. However, vascular complications are a limitation for the management of these patients. This trial aimed to determine the effectiveness and safety of the Cross-Seal suture-mediated vascular closure device in obtaining hemostasis at the target limb access site following interventional procedures using 8F to 18F procedural sheaths. The Cross-Seal IDE trial (Investigational Device Exemption) was a prospective, single-arm, multicenter study in subjects undergoing percutaneous endovascular procedures utilizing 8F to 18F ID procedural sheaths. The primary efficacy end point was time to hemostasis at the target limb access site. The primary safety end point was freedom from major complications of the target limb access site within 30 days post procedure. A total of 147 subjects were enrolled between August 9, 2019, and March 12, 2020. Transcatheter aortic valve replacement was performed in 53.7% (79/147) and percutaneous endovascular abdominal/thoracic aortic aneurysm repair in 46.3% (68/147) of subjects. The mean sheath ID was 15.5±1.8 mm. The primary effectiveness end point of time to hemostasis was 0.4±1.4 minutes. An adjunctive intervention was required in 9.2% (13/142) of subjects, of which 2.1% (3/142) were surgical and 5.6% (8/142) endovascular. Technical success was achieved in 92.3% (131/142) of subjects. Freedom from major complications of the target limb access site was 94.3% (83/88). In selected patients undergoing percutaneous endovascular procedures utilizing 8F to 18F ID procedural sheath, Cross-Seal suture-mediated vascular closure device achieved favorable effectiveness and safety in the closure of the large-bore arteriotomy. URL: https://www.clinicaltrials.gov; Unique identifier: NCT03756558.

Etiology, pathogenesis, and management of angiosarcoma associated with implants and foreign body: Clinical cases and research updates.

Angiosarcomas are rare and highly malignant soft tissue sarcomas originating from endothelial cells lining the lymphatic or vascular system. While they predominantly emerge from (sub)cutaneous regions, occurrences have been reported throughout the body. The etiology of angiosarcoma remains elusive in most clinical cases. Nevertheless, several prognosis risk factors play a pivotal role, including chronic lymphedema, therapeutic irradiation, environmental carcinogens, familial syndromes, and the presence of foreign materials like metallic objects and biomedical implants. Despite evidence implicating retained foreign material in angiosarcoma development, understanding its prognosis and pathogenesis remains limited. The pathogenesis of angiosarcoma appears to involve a complex interplay of chronic inflammation, tissue remodeling, and genetic factors that create a conducive microenvironment for malignant transformation. Management of these sarcomas remains challenging due to their infiltrative nature owing to the high chance of metastasis and local recurrence. The primary treatment modalities currently include surgery, radiotherapy, and chemotherapy, but recent advances in targeted immunotherapy and gene therapy hold promise for more effective approaches. This comprehensive review delves into the potential etiological and pathogenic roles of foreign materials, such as metallic objects, biomedical implants, and biomaterials, in the development of angiosarcoma. Further research into the underlying molecular mechanisms could provide valuable insights for tailored management and developing novel targeted therapeutic strategies.

Paradoxical Air Embolism in Spinal Surgery: Case Report and Literature Review

AbstractAir embolism (AE) is a subtype of embolism, caused by the entry of air into the vascular system. It is a predominantly iatrogenic complication, and its symptomatic form is severe, although uncommon. In some cases, a venous thrombi may pass into the arterial system through a venous-arterial shunt, characterizing a paradoxical embolism. Here, we describe the case of a previously healthy 44-year-old female who underwent cauda equina decompression and lumbar epidural abscess drainage. The patient suffered a paradoxical AE intraoperatively and died after 4 days. The occurrence of AE in lumbar spine surgeries in the prone position is rare, but the surgical team must be attentive to its clinical signs and quickly institute initial management when necessary.

Cell wall-mediated root development is targeted by a soil-borne bacterial pathogen to promote infection

Plant pathogens manipulate host development, facilitating colonization and proliferation. Ralstonia solanacearum is a soil-borne bacterial pathogen that penetrates roots and colonizes plants through the vascular system, causing wilting and death. Here, we find that RipAC, an effector protein from R.solanacearum, alters root development in Arabidopsis, promoting the formation of lateral roots and root hairs. RipAC interacts with CELLULOSE SYNTHASE (CESA)-INTERACTIVE PROTEIN 1 (CSI1), which regulates the activity of CESA complexes at the plasma membrane. RipAC disrupts CESA-CSI1 interaction, leading to a reduction in cellulose content, root developmental alterations, and a promotion of bacterial pathogenicity. We find that CSI1 also associates with the receptor kinase FERONIA, forming a complex that negatively regulates immunity in roots; this interaction, however, is not affected by RipAC. Our work reveals a bacterial virulence strategy that selectively affects the activities of a host target, promoting anatomical alterations that facilitate infection without causing activation of immunity.

ZmCals12 impacts the maize growth and development by regulating symplastic transport

Carbohydrate partitioning from source to sink tissues is critical for plant growth and development. However, in maize (Zea mays L.), the molecular mechanisms of callose synthase gene regulating this process have seldom been reported. Here, we show that the mutation of maize callose synthase12 (ZmCals12) caused increased accumulation of carbohydrate in the photosynthetic leaves but reduced carbohydrate content in sink tissues, which led to plant dwarfing and male sterile. Histochemical GUS activity assay and mRNA in situ hybridization (ISH) indicated that ZmCals12 was mainly expressed in the vascular transport system. Loss-of-function of ZmCals12 reduced callose synthase activity and callose deposition in plasmodesmatas (PDs) and around phloem cells (PCs) of vascular bundle. The drop-and-see (DANS) assay revealed that the PD permeability in the photosynthetic cells and the transport competence of leaf veins were reduced in the Zmcals12 mutants, which led to the reduced symplastic transport. Paraffin section experiment revealed that less-developed vascular cells (VCs) in the Zmcals12 mutants potentially disturbed sugar transport, thus resulting in the pleiotropic phenotype of the Zmcals12 mutants. In addition, the impaired sugar transport hindered the internode development by inhibiting auxin (IAA) biosynthesis and signaling in the Zmcals12 mutant. Collectively, our results provide insights into the mechanism of ZmCals12-mediated callose deposition and symplastic transport governing maize growth and development.

Acute superior mesenteric artery thrombosis in a 34-year-old male with thrombophilia: a case report

Acute superior mesenteric artery thrombosis in a 34-year-old male with thrombophilia: a case report

Vascular Endothelial Growth Factor (VEGF) and Its Role in the Progression and Development of Breast Tumor

Breast cancer is the most common type of cancer in women and is widely known. Angiogenesis is the process through which new blood vessels develop from the body's current vascular system. It is essential for tumor growth, invasiveness, and metastasis, and so plays a pivotal role in the development of carcinoma. Proteolytic and proangiogenic catalyst activators and inhibitors regulate angiogenesis in a hierarchical fashion. The angiogenic process is largely under the direction of VEGF. In a select number of malignant tumors, the VEGF gene is overexpressed. The function of VEGF in angiogenesis has been the subject of intensive study in recent years. In breast cancer patients, VEGF plasma levels are highly predictive of tumor growth and survival. Several VEGF gene polymorphisms, have been identified to affect gene expression level in prior investigations. Epidemiological studies have linked polymorphisms in the VEGF gene to altered cancer risk, tumor growth, and metastasis. Previous research on VEGF polymorphism to evaluate the association between genes and breast cancer susceptibility was scant. The current review discusses the role of VEGF in the progression of breast cancer in addition to its promising usage as a predictive marker for breast cancer.

Deletion of Sigmar1 leads to increased arterial stiffness and altered mitochondrial respiration resulting in vascular dysfunction.

Sigmar1 is a ubiquitously expressed, multifunctional protein known for its cardioprotective roles in cardiovascular diseases. While accumulating evidence indicate a critical role of Sigmar1 in cardiac biology, its physiological function in the vasculature remains unknown. In this study, we characterized the expression of Sigmar1 in the vascular wall and assessed its physiological function in the vascular system using global Sigmar1 knockout (Sigmar1-/-) mice. We determined the expression of Sigmar1 in the vascular tissue using immunostaining and biochemical experiments in both human and mouse blood vessels. Deletion of Sigmar1 globally in mice (Sigmar1-/-) led to blood vessel wall reorganizations characterized by nuclei disarray of vascular smooth muscle cells, altered organizations of elastic lamina, and higher collagen fibers deposition in and around the arteries compared to wildtype littermate controls (Wt). Vascular function was assessed in mice using non-invasive time-transit method of aortic stiffness measurement and flow-mediated dilation (FMD) of the left femoral artery. Sigmar1-/- mice showed a notable increase in arterial stiffness in the abdominal aorta and failed to increase the vessel diameter in response to reactive-hyperemia compared to Wt. This was consistent with reduced plasma and tissue nitric-oxide bioavailability (NOx) and decreased phosphorylation of endothelial nitric oxide synthase (eNOS) in the aorta of Sigmar1-/- mice. Ultrastructural analysis by transmission electron microscopy (TEM) of aorta sections showed accumulation of elongated shaped mitochondria in both vascular smooth muscle and endothelial cells of Sigmar1-/- mice. In accordance, decreased mitochondrial respirometry parameters were found in ex-vivo aortic rings from Sigmar1 deficient mice compared to Wt controls. These data indicate a potential role of Sigmar1 in maintaining vascular homeostasis.

Cardiovascular Reflexes - Vagus as the Key Player.

The cardiac and vascular systems work in coordination by activating various reflex mechanisms based on the body's needs. These may be during physiological variations or pathophysiological changes seen in disease conditions of varying degrees of severity. This article intends to explain various reflexes involved in the homeostasis of the cardiovascular system and the role of vagus as the key component in all these reflexes. The article also explains the components of the reflex arc, the stimulus and response, and the role of reflex in a few diseases. This article describes 22 different cardiovascular reflexes in detail.

Bioprinting of Perfusable, Biocompatible Vessel-like Channels with dECM-Based Bioinks and Living Cells

There is a growing interest in the production of bioinks that on the one hand, are biocompatible and, on the other hand, have mechanical properties that allow for the production of stable constructs that can survive for a long time after transplantation. While the selection of the right material is crucial for bioprinting, there is another equally important issue that is currently being extensively researched—the incorporation of the vascular system into the fabricated scaffolds. Therefore, in the following manuscript, we present the results of research on bioink with unique physico-chemical and biological properties. In this article, two methods of seeding cells were tested using bioink B and seeding after bioprinting the whole model. After 2, 5, 8, or 24 h of incubation, the flow medium was used in the tested systems. At the end of the experimental trial, for each time variant, the canals were stored in formaldehyde, and immunohistochemical staining was performed to examine the presence of cells on the canal walls and roof. Cells adhered to both ways of fiber arrangement; however, a parallel bioprint with the 5 h incubation and the intermediate plating of cells resulted in better adhesion efficiency. For this test variant, the percentage of cells that adhered was at least 20% higher than in the other analyzed variants. In addition, it was for this variant that the lowest percentage of viable cells was found that were washed out of the tested model. Importantly, hematoxylin and eosin staining showed that after 8 days of culture, the cells were evenly distributed throughout the canal roof. Our study clearly shows that neovascularization-promoting cells effectively adhere to ECM-based pancreatic bioink. Summarizing the presented results, it was demonstrated that the proposed bioink compositions can be used for bioprinting bionic organs with a vascular system formed by endothelial cells and fibroblasts.

Paricalcitol Has a Potent Anti-Inflammatory Effect in Rat Endothelial Denudation-Induced Intimal Hyperplasia.

Neointimal hyperplasia is the main cause of vascular graft failure in the medium term. Vitamin D receptor activation modulates the biology of vascular smooth muscle cells and has been reported to protect from neointimal hyperplasia following endothelial injury. However, the molecular mechanisms are poorly understood. We have now explored the impact of the selective vitamin D receptor activator, paricalcitol, on neointimal hyperplasia, following guidewire-induced endothelial cell injury in rats, and we have assessed the impact of paricalcitol or vehicle on the expression of key cell stress factors. Guidewire-induced endothelial cell injury caused neointimal hyperplasia and luminal stenosis and upregulated the expression of the growth factor growth/differentiation factor-15 (GDF-15), the cytokine receptor CD74, NFκB-inducing kinase (NIK, an upstream regulator of the proinflammatory transcription factor NFκB) and the chemokine monocyte chemoattractant protein-1 (MCP-1/CCL2). Immunohistochemistry confirmed the increased expression of the cellular proteins CD74 and NIK. Paricalcitol (administered in doses of 750 ng/kg of body weight, every other day) had a non-significant impact on neointimal hyperplasia and luminal stenosis. However, it significantly decreased GDF-15, CD74, NIK and MCP-1/CCL2 mRNA expression, which in paricalcitol-injured arteries remained within the levels found in control vehicle sham arteries. In conclusion, paricalcitol had a dramatic effect, suppressing the stress response to guidewire-induced endothelial cell injury, despite a limited impact on neointimal hyperplasia and luminal stenosis. This observation identifies novel molecular targets of paricalcitol in the vascular system, whose differential expression cannot be justified as a consequence of improved tissue injury.

Graphene Oxide (GO)-Based Bioink with Enhanced 3D Printability and Mechanical Properties for Tissue Engineering Applications.

Currently, a major challenge in material engineering is to develop a cell-safe biomaterial with significant utility in processing technology such as 3D bioprinting. The main goal of this work was to optimize the composition of a new graphene oxide (GO)-based bioink containing additional extracellular matrix (ECM) with unique properties that may find application in 3D bioprinting of biomimetic scaffolds. The experimental work evaluated functional properties such as viscosity and complex modulus, printability, mechanical strength, elasticity, degradation and absorbability, as well as biological properties such as cytotoxicity and cell response after exposure to a biomaterial. The findings demonstrated that the inclusion of GO had no substantial impact on the rheological properties and printability, but it did enhance the mechanical properties. This enhancement is crucial for the advancement of 3D scaffolds that are resilient to deformation and promote their utilization in tissue engineering investigations. Furthermore, GO-based hydrogels exhibited much greater swelling, absorbability and degradation compared to non-GO-based bioink. Additionally, these biomaterials showed lower cytotoxicity. Due to its properties, it is recommended to use bioink containing GO for bioprinting functional tissue models with the vascular system, e.g., for testing drugs or hard tissue models.

A Combined Endodontic Management Approach in immature Permanent Molar tooth with Periapical Lesion: Case Report

Immature dental pulp, which has a highly cellular structure and a rich vascular nutrition system, is highly resistant to inflammation, In these teeth, determining the treatment option based on clinical and radiographic findings alone may result in the removal of diseased pulp tissue as well as vital pulp tissue. In order to increase the prognosis of these teeth, vital pulp treatments are highly recommended to preserve pulp vitality. By evaluating the condition of the root pulps of young permanent molars separately, it is possible to increase the prognosis of the tooth by combining regenerative endodontic treatment and pulpotomy treatment according to the condition of the pulps. In this case report, regenerative endodontic treatment and pulpotomy treatment were applied to different root canals of the first molar, which became necrotic before completing its maturation due to caries and had an apical lesion, and excellent healing was demonstrated. Key words: Biodentine, immature permanent teeth, periapical lesions, pulpotomy, regenerative endodontic treatment.

Sonographically-guided Parasacrum Infrapiriformis Drainage of Deep Pelvic Abscesses: An Anatomical Safety Study Using SYNAPSE VINCENT.

Deep pelvic abscesses are surrounded by the pelvic bones, bladder, gynecological organs, intestinal tract, and nerve and vascular systems, and are approached by various routes for drainage. The transgluteal approach is often performed under computed tomography guidance; however, if ultrasonography can be used to confirm the approach, it is considered more effective because it reduces radiation exposure and allows for real-time puncture under sonographic and fluoroscopic guidance. This retrospective study was conducted at Tobata Kyoritsu Hospital (Fukuoka, Japan) between April 1, 2021, and December 31, 2022. Sonographically guided transgluteal drainage with fluoroscopy was performed in five consecutive cases of deep pelvic abscesses using a 3D image analysis system (SYNAPSE VINCENT) to study the anatomy for safe puncture. Three patients had postoperative abscesses from colorectal cancer, one caused by perforation of the appendicitis, and one caused by sigmoid diverticulitis. The average drainage duration was 11 days (SD = 6.7). No complications, such as bleeding or nerve damage, were observed. We constructed a 3D image of the puncture route of the trans greater sciatic foramen using SYNAPSE VINCENT to objectively comprehend the anatomy and puncture route. The ideal transgluteal approach is to insert the catheter as close to the sacrum as possible at the level of the infrapiriformis. The parasacrum infrapiriformis approach can be performed safely and easily using ultrasound guidance and fluoroscopy.