Ascending thoracic aortic aneurysm is a life-threatening disease, which is difficult to detect prior to the occurrence of a catastrophe. Epidemiology patterns of ascending thoracic aortic dilations/aneurysms remain understudied, whereas the risk assessment of it may be improved. The electronic databases PubMed/Medline 1966–2022, Web of Science 1975–2022, Scopus 1975–2022, and RSCI 1994–2022 were searched. The current guidelines recommend a purely aortic diameter-based assessment of the thoracic aortic aneurysm risk, but over 80% of the ascending aorta dissections occur at a size that is lower than the recommended threshold of 55 mm. Moreover, a 55 mm diameter criterion could exclude a vast majority (up to 99%) of the patients from preventive surgery. The authors review several visualization-based and alternative approaches which are proposed to better predict the risk of dissection in patients with borderline dilated thoracic aorta. The imaging-based assessments of the biomechanical aortic properties, the Young’s elastic modulus, the Windkessel function, compliance, distensibility, wall shear stress, pulse wave velocity, and some other parameters have been proposed to improve the risk assessment in patients with ascending thoracic aortic aneurysm. While the authors do not argue for shifting the diameter threshold to the left, they emphasize the need for more personalized solutions that integrate the imaging data with the patient’s genotypes and phenotypes in this heterogeneous pathology. Ascending thoracic aortic aneurysm is a life-threatening and insidious disease that is difficult to detect prior to the occurrence of a catastrophe ,2. A sinThe timely diagnosis and pre-emptive management of it are essential, and patients may benefit from an elective aortic repair if a twelve-month risk of the aneurysm rupture/dissection exceeds the combined risks of the perioperative morbidity and mortality. The patients with thoracic aortic aneurysms who receive later elective surgeries experience significantly worse outcomes when they are compared with the medically triaged candidates . The curThe questions on the personalization of the indications for the pre-emptive open repair and potential left-shift of diameter-based criterion continue to be discussed in the literature. Moreover, alternative approaches to assessing the risk of ascending aortic aneurysm dissection/rupture are currently under development, and they may potentially result in the elaboration of more precise tools to select the patients for pre-emptive open aortic repair. A personalized risk assessment may be the most promising strategy for establishing adequate indications for the pre-emptive open repair of ascending thoracic aorta. The aim of this article is to discuss the approaches to a personalized risk prediction in ascending thoracic aortic disease.To find the relevant literature data, the electronic databases such as PubMed/Medline (1966–2022), Web of Science (1975–2022), Scopus (1975–2022), and Russian Science Citation Index (RSCI) (1994–2022) were searched. The search terms were as follows: ascending aorta, thoracic aorta, aortic dilatation, thoracic aortic aneurism, aortic aneurysm, aortic dissection, computed tomography, echocardiography, magnetic resonance imaging, ultrasound, hemodynamics, machine learning, prophylactic surgery, prediction, and risk. The Web of Science Core Collection, Scopus, and RSCI data were used to find, analyze, and review the citation reports and papers that cited the relevant publications, which were retrieved during the primary search. After an initial retrieval of 3615 results, 70 papers were selected based on the criteria of relevance, novelty, and for the avoidance of duplication.The current guidelines recommend that a pre-emptive open aortic repair be conducted if the aortic diameter reaches 55 mm. However, a study, which is based on serial imaging examinations, suggested that the aortic diameter of 55 mm may be an imperfect predictor of an aortic catastrophe . The stu2), correlates with aortic catastrophes and deaths, and an index of 4.25 cm/m2 is associated with 20% annual risk [Zafar et al. showed that indexing the absolute aortic size to the biometric data is a valid tool for a risk estimation of the occurrence of rupture, dissection, or death in patients with ascending thoracic aortic aneurysms. It allows the authors to compensate for the risk differences that are skewed by stature, though the aortic sizes and behaviors are significantly influenced by sex . This prual risk . The aorual risk .The aortic length characterizes the natural history of the ascending thoracic aortic aneurysm, and the measure of it is used to develop the new predictive tools to improve the risk stratification ,15,16,17Magnetic resonance imaging (MRI) provides accurate dimensional measurements of the aortic root/ascending aorta/aortic arch. It provides an excellent image quality in the motion-prone segments with a short acquisition time ,19. BesiA proof-of-concept study identified three hemodynamic measures that were superior to the current standard of care (aneurysm size) in the evaluation of future aneurysm growth. The measures included the carotid-femoral pulse wave velocity, the central pulse pressure, and the forward pressure wave amplitude. Among these, the carotid-femoral pulse wave velocity and the central pulse pressure require only the arterial tonometry for their assessment, and they are proposed for future simple and easily adoptable clinical algorithms to predict the thoracic aortic aneurysm expansion . Other sThe biomechanical properties of the ascending aorta have been studied using various approaches. An intraoperative video-based method was proposed to assess the local biaxial strains of the ascending thoracic aorta in patients who were undergoing open-chest surgery. Repeated biaxial strain measurements were obtained at low- and high-pressure conditions with reliable precision. This method may be used to further study the biomechanical properties of the ascending thoracic aorta in various relevant populations of patients who are undergoing open-chest surgery. The method builds a foundation for clinically relevant biomechanical modeling and mechanobiological profiling .The imaging-based monitoring of the biomechanical properties of the aortic wall may help to identify the patients with a borderline aortic dilatation that require pre-emptive surgery. The biomechanical parameters characterizing the distensibility and mechanical elasticity of the ascending aorta may be assessed using the data of the aortic deformations during the cardiac cycle in routine practice based on an electrocardiogram (ECG)-synchronized MRI. Serial cardiac magnetic resonance (CMR) measurements demonstrate that ascending aortic distensibility declined in BAV patients even faster than it did in a comparison group with connective tissue disorders . A prospE—Young’s elastic modulus (Pa);diast—diastolic aortic diameter;dpulse—an increase in aortic diameter during systole;∆d0.25—squared Poisson ratio for the aorta wall (Poisson ratio is known to be 0.5);h—aorta wall thickness during diastole;pulse—pulse arterial blood pressure;ABP133.3—mmHg to Pa conversion factor.Young’s elastic modulus is the ratio of the tensile stress to strain. Higher values of tensile strength and Young’s modulus are present in patients with an ascending aortic aneurysm , but stuA group of patients underwent ECG-synchronized MRI-based aortography for months before some of them developed an ascending aortic aneurysm. The values of the Young’s elastic modulus in all of the patients who later developed the aneurysms exceeded 0.67 mPa, though the study was limited by its retrospective nature and small sample size . The invThe capacitance or the Windkessel function characterizes the aorta acting as an elastic buffering chamber behind the heart. The aorta stores about 50% of the left ventricular stroke volume during systole, and it releases the elastic forces during diastole. Energy loss is the measure of the Windkessel function. Recently, the biomechanics of normal, dilated, and dissecting ascending aortas were studied via destructive testing ,35. The One of the potential areas of growth in identifying the candidates for pre-emptive open aortic repair is the study of fluid hemodynamics and vortical patterns in the proximal aorta because the ascending thoracic aortic aneurysm progression may be partially flow-mediated . The firNew hemodynamic tools allow us to study the vorticity scores, the qualitative helicity, the quantitative vorticity, the local normalized helicity, the abnormally directed velocity volume, and the wall shear stress (WSS) surface in ascending aorta disease . A WSS tA valuable tool was developed to study the hemodynamic alterations in the diseased aorta depending on the aortic shape and the aortic valve variations which were based on statistical shape modeling. The tool was designed to support the risk assessment in patients with thoracic ascending aortic disease over time. The authors created the ascending thoracic aortic aneurysm template, which may be modelled to see the differences that it produces in the flow patterns, blood pressure, and fluid shear forces when they are deformed. The authors performed the exquisite atlas-based analyses to understand the mechanistic link between the shape and the pathophysiology .The hemodynamic patterns depend on the blood flow eccentricity at the aortic root regardless of the aortic valve phenotype . The bloRegional hemodynamic and biomechanical characteristics depend on different rotational positions of the normal aortic root . The velComputational fluid dynamics enable us to evaluate the vorticity, the helicity index, a disturbed laminar flow, the flow streamline, the flow velocity, the WSS, and the recirculation regions in untreated and treated aortic diseases, and other fluid dynamic parameters ,47,48,49The phenotypical “associates” of the silent thoracic aortic aneurysm may help in detecting this condition at an early stage. They include BAV, giant cell arteritis, having a family history of aortic aneurysms, positive thumb-palm sign , an intrThe BAV is one of the most significant phenotypical associates requiring attention. The TTE is the imaging technique of choice to diagnose a BAV. The measurement of the aortic root diameter should be made perpendicular to the axis of the proximal aorta, and it should be recorded from several slightly differently oriented long-axis views. The standard measurement is taken as the largest diameter from the right coronary sinus of Valsalva to the posterior  sinus. Most of the studies report aortic root diameter measurements at the end-diastole using the leading edge-to-leading edge technique . The TTEThoracic aortic disease is detected twice as often in individuals with anomalies of the aortic arch such as a bovine aortic arch, an isolated left vertebral artery, and an aberrant right subclavian artery. Atypical branching variants are potential anatomic markers predicting thoracic aortic disease . A majorThe “thumb palm test” is often positive  in ascending aortic aneurysm patients. The sensitivity of the test is low (7.5%), but specificity of it is high (98.5%) .Interestingly, there is a paradoxical beneficial effect of diabetes on the thoracic aortic catastrophe risk. Diabetic patients have a slower rate of the aortic aneurysm growth, a lower aortic dissection rate, an older age at which the rupture occurs (>65 years), a lower mortality rate, a reduced hospital stay, an attenuated matrix metalloproteinases, and an increased aortic wall stress. The clinical and experimental studies demonstrate the ability of antidiabetic medications to inhibit the aortic aneurysm growth. Metformin, thiazolidinediones, and dipeptidyl peptidase-4 inhibitors may protect against an aneurysm and inhibit its growth . AnotherNew risk factors may emerge due to the ongoing pandemic of the coronavirus disease 2019 (COVID-19) infection. Indeed, a severe acute respiratory syndrome coronavirus 2 infection (SARS-CoV-2) can deteriorate the biomechanical properties of the ascending aorta . A singlDeep learning techniques integrating the imaging data, the electronic health record data, and genetic sequences ,66,67,68The study implementing a deep learning approach on aortic MRI data from the UK Biobank was able to measure the aortic diameter of over 30,000 individuals. This genome-wide association study identified the gene encoding supervillin (SVIL gene) , which is highly expressed in the vascular smooth muscle, as being significantly associated with both ascending and descending aortic dilatation .The relationships between the aortic shape and the ascending aortic aneurysm rupture risk were studied via a machine learning approach using finite element analysis. The approach allowed for nearly 96% risk classification accuracy, though the authors used limited sets of imaging data to train the algorithm, whereas the material properties and the inhomogeneous thickness factors were not included .Machine learning may become a promising technique allowing for the personalization of the risk assessment in patients with ascending thoracic aortic dilations. However, we expect that there will be many more parameters which will be integrated into the machine learning algorithms to provide an appreciable discrimination power .Though not all of the reviewed approaches are immediately applicable to the daily clinical practice, the calculation of Young’s elastic modulus and the assessment of central hemodynamics are fairly straightforward techniques for routine clinical practice. They may be readily used with the available equipment, requiring minimum additional training of the imaging specialists. In fact, the main idea of the approach that is presented here in this review, is the real necessity of the practical implementation of mechanical parameters to the routine clinical practice activity in diagnostic and surgical angiology, for example, in the first line, the use of the individually calculated Young’s modulus for the individual prognosis of patients with extensive aortic disease. The matter of the implementation of such an approach to everyday clinics can only be achieved through the development of attractive software that can deliver a three-dimensional distribution of the Young’s modulus values throughout the wall of aorta from the ECG-gated MRI-aortography. Currently, the design of such specialized packages is in progress.Some of the discussed technologies require the sophisticated processing of the data, a complicated interpretation of it, and additional time and resources, whereas the majority of clinicians are not acquainted with these techniques. However, during the next decade, even the most sophisticated approaches for the management of patients with ascending aortic dilatation may be incorporated into the daily clinical practice in leading specialized centers. The practical implementation of transdisciplinary algorithms would require an integration of the advanced imaging modalities, a phenotypic assessment, genetics, machine learning, clustering, and neural network-based algorithms supporting the decision-making in selecting candidates for preemptive open aortic repair.The main obstacle to implementing the transdisciplinary approach is the lack of coordination between the specialists from different disciplines, the fragmentation of the data, and the unawareness of the untrained clinicians. Data, which are acquired by using different techniques and produced by specialists whose professional paths do not overlap, should be integrated like fragments of a puzzle. The way to develop the transdisciplinary effort may be a creation of a cloud platform with different domains to provide an efficient clustering of the patients/candidates for surgery.During the next decade, the authors of this paper also plan to develop and implement a formula for calculating the risk of surgery based on clinical, genetic, tomographic, and echocardiography data, taking into account the anatomic determinants and functional status of the aortic wall in the patients with an ascending aortic dilatation. This risk of the surgery will be weighed against the risk of the complications in marginally dilated ascending aortas and aortic roots. Such an approach would allow for us to make a balanced decision regarding the best personalized time for the open reconstruction of the ascending aorta and/or aortic root. The second task may be achieved through the use of a machine learning in a framework of the above-mentioned transdisciplinary approach.It should be emphasized that the risk assessment of the complications in a moderately dilated ascending thoracic aorta/aortic root essentially differs from that in the descending thoracic aorta. The problem of the dissection of the ascending aorta is associated with a higher mortality rate and there being less time for decision-making than there are in the type B dissection. Moreover, the type B dissection may be treated less invasively, non-surgically or endovascular, in many world centers. Overall, the aneurysm of the descending aortas may be dynamically monitored for a longer time. It is believed that the size of it does not matter much in predicting acute type B aortic dissection . The proIn summary, a clinically relevant identification of the predictors is based on non-invasive or, sometimes, semi-invasive, imaging techniques such as MRI, CT, and ultrasound, and the current guidelines recommend the use of the aortic diameter-based assessment of the thoracic aortic aneurysm risk. However, thoracic aortic dilatation is a heterogeneous condition, and over 80% of ascending aorta dissections might occur at a size that is lower than the recommended threshold of 55 mm. Several alternative approaches have been proposed to predict the risk of dissection in patients with a borderline-dilated thoracic aorta, namely: measuring the alternative aortic dimensions (aortic length and aortic size indexes), assessing the biomechanical aortic properties , the energy loss, genotyping and integrating all of the above with the patient’s phenotypes . The standardized assessment of the mechanoelastic properties may be a promising, straightforward approach for an early risk assessment, but further research is required as the studies in this direction are nascent. New risk factors for thoracic aortic disease have emerged due to the ongoing coronavirus disease 2019 (COVID-19) infection pandemic. The epidemiological rates and patterns of ascending thoracic aortic dilations/aneurysms require continuous attention and systematic multi-center screening programs to identify the prevalence and diagnostic yields of ascending thoracic aortic disease. More sensitive indices are warranted to better discriminate between the aortopathy types to develop tools to select patients for the early pre-emptive surgery. While we do not argue for shifting the diameter threshold to the left, we do emphasize the need for more personalized solutions that integrate the imaging data with the patient’s genotypes and phenotypes in this heterogeneous pathology. Taking into account the sixth techno-economic paradigm, we conclude that interdisciplinary methods are not enough to further advance the state of the knowledge regarding the practice-oriented assessment of the ascending aortic aneurysm risk. Instead, it requires the use of transdisciplinarity methods and the emergence of new scientific disciplines, allowing for researchers to build the effective virtual cognitive centers. Meanwhile, a purely aortic diameter-based assessment of the thoracic aortic aneurysm risk will remain the standard of care.


A dorsal skinfold window-chamber model with tail vein injection of Texas red-dextran was established to confirm the optimal observation time of microvessels. OECs-DBM complex under static and dynamic perfusion culture was implanted into the model to analyze vascularization. OECs-DBM complex was harvested on 12th day for HE staining and fluorescent imaging. The model was successfully constructed, and the most appropriate time to observe microvessels was 15 min after injection. The ingrowth of recipient microvessels arcoss the border of OECs-DBM complex increased with time in both groups, and more microvessels across the border were observed in dynamic perfusion group on 3rd, 5th, 7th day. Fluorescent integrated density of border in dynamic perfusion group was higher at all-time points, and the difference was more significant in central area. Fluorescent imaging of OECs-DBM complex exhibited that no enhanced green fluorescent protein-positive cells were found beyond the verge of DBM scaffold in both groups. In vitro prevascularization by dynamic perfusion culture can increase and accelerate the blood perfusion of OECs-DBM complex obtained from recipient microvasculature by internal inosculation. Accordingly, this approach may markedly contribute to the future success of tissue engineering applications in clinical practice.The current research on seed cells and scaffold materials of bone tissue engineering has achieved milestones. Nevertheless, necrosis of seed cells in center of bone scaffold is a bottleneck in tissue engineering. Therefore, this study aimed to investigate the   Successful construction of the dorsal skinfold window-chamber model.The number of inosculation vessels increases faster in dynamic perfusion group.Prevascularized OECS-DBM fuses with recipient vessels via internal inosculation.in vivo prevascularization [in vitro prevascularization [At present, large segmental bone defects are still a major clinical challenge in orthopedics. Bone tissue engineering is one of the ways to solve this dilemma. There are many strategies to promote vascularization of tissue-engineered bone, including the slow release of pro-vascular growth-related factors such as vascular endothelial growth factor (VEGF) , in vivorization  and in vrization . The crirization . With thrization ,4. Howevrization ,13. It cIn vitro prevascularization can be achieved by growing endothelial cells (ECs) on a scaffold. ECs have the potential to spontaneously form blood vessels [in vitro amplification capacity. Allogeneic-derived vascular ECs are more difficult to apply due to their immunogenicity, and the density of cells is not easily regulated when seeded into the scaffold. Peripheral blood-derived outgrowth endothelial cells (OECs), as cells with proliferative and differentiation potential toward mature ECs, are an important source of autologous vascular ECs, and widely available and easy to obtain. As precursors of mature ECs, OECs have cell morphology similar to mature ECs, express partially similar cell surface markers, and more importantly, have superior proliferative potential and angiogenic capacity [For this reason, the field of tissue engineering has gradually developed prevascularization techniques. The basic concept of prevascularization technology is to pre-build a microvascular network on a tissue-engineered product before it is implanted into the body. Its advantage is that the tissue-engineered product does not have to wait for the recipient vessels to grow in slowly after implantation, but only needs the microvascular network on the scaffolds to inosculation with the recipient vessels ,15, so t vessels ,16. The capacity ,18. OECscapacity . Periphecapacity .in vitro prevascularization of DBM [Our previous studies have demonstrated that a dynamic perfusion system administering continuous fluid shear stress to OECs on demineralized bone matrix (DBM) enhances spreading adhesion, proliferation, differentiation to mature ECs, and three-dimensional tube formation in matrix pores, contributing to n of DBM . Based oIsolation and identification of OECs, preparation of OECs-DBM scaffolds and static and dynamic perfusion cultures of OECs-DBM scaffolds were performed as previously described . BALB/C As shown in Nude mice were immobilized on homemade observation stands on days 1, 3, 5, 7, 9, and 12 after scaffold implantation. Texas red-dextran liquid was injected approximately 15 min prior to performing the observation. The observation stand was moved to the fluorescence microscope and imaged and taken pictures.The number of ingrowth vessels at OECs-DBM scaffold border was detected. In a nutshell, the enhanced green fluorescent protein-labeled green fluorescent cells were first observed under a fluorescent microscope  to determine the extent of the OECs-DBM scaffold edge, and then the vessels were searched and counted along the border of the OECs-DBM scaffolds . The criteria for new growth into the vessel at the edge of the scaffolds were that it did not appear on first observation but presented on later observation and extended into the scaffold area. The above process was operated by two investigators to minimize manual counting errors, and the results were incorporated into the data records after both parties agreed.Blood perfusion of OECs-DBM scaffolds was detected. Under fluorescence microscopy , four randomly selected fields of view were photographed at the center and border of the scaffolds, respectively. The red fluorescence cumulative fluorescence density values were calculated using Image J software  to reflect the blood perfusion of the OECs-DBM scaffolds.On day 12 of OECs-DBM scaffold implantation, the scaffolds and its surrounding full-thickness skin within a range of about 0.5 cm were excised, and hard tissue sections were stained with HE staining and fluorescence observation to investigate the fusion mechanism. Briefly, the vascularized observation window was removed from the dorsal surface. The scaffold was removed to an extent of approximately 0.5 cm around the OECs-DBM scaffold, and then the scaffold was cut along with the full skin layer at its base. Paraformaldehyde (4%) was fixed for 2–3 days, and specimens requiring fluorescence observation were fixed in 70% alcohol. Subsequently, the samples were permeabilized, embedded, blocked, sectioned, and mounted. Finally, HE staining of the sections was performed by referring to the kit instructions . The distribution of cells in the scaffolds was observed under an optical microscope . Fluorescence microscopy  to observe the distribution of fluorescent cells in the sections.t-test was used for comparison between two groups, and measurements of the same subject at different observation time points were analyzed using ANOVA with repeated measurement data. Differences were considered statistically significant at P < 0.05.SPSS 20.0 statistical software was used for the analysis, and the data were expressed as mean ± standard deviation. After the data were tested for normal distribution and chi-square, in vitro dynamic perfusion systems promote the ability of OECs to spread adhesion, proliferation, and three-dimensional tube formation on the DBM. Nevertheless, under this condition, the vascularization process of OECs-DBM scaffolds and the mechanism of their fusion with the vessels in the recipient area are not clear in vivo. Accordingly, we intend to observe the role of in vitro dynamically perfused OECs-DBM scaffolds by constructing a dorsal skinfold window-chamber model.Our previous studies have shown that All nude mice survived the modeling process and passed the shock period smoothly. The pressure of the vascular observation window was moderate, and the surrounding skin was free of infection and compression necrosis.After tail vein injection of Texas red dextran, the fluorescence microscopy showed that the microvessels were visible after about 5 min, and the vascular paths were basically the same as those under the light microscope . After tBefore and after injection of Texas red-dextran, the image was blurred in the light microscopic field of view, smudges were visible, the image background lacked contrast with the vessels, and the vessels were poorly displayed . The fluFurther, we counted new growth into the vessel at the edge of the OECs-DBM scaffold. The result exhibited that the OECs-DBM scaffold gradually grew into microvessels around the recipient area after implantation . With thThe OECs-DBM scaffold was seen to be white when it was first implanted and then gradually turned yellow. The skin and subcutaneous tissue around the window regenerated and approached the scaffold within the observation window, and the surrounding vessels regenerated and gradually grew into the scaffold. At the end of the observation, the scaffold turned red, and new vessels grew into the scaffold border and central area surface . StatistIn the static culture group, HE results displayed that the cells on the OECs-DBM scaffold were unevenly distributed and formed cell clumps. There was no or occasional ring-shaped tubular structure of intact cells in the pores of the scaffold, and inflammatory cell infiltration was seen . Under tin vivo specimens and in vivo observations. The in vivo method is only applicable to the observation of microvasculature in dead or isolated specimens, neither of which reflects the microvascular condition in the normal physiological state. Notably, Sandison et al. first applied the animal dorsal skinfold window-chamber model to observe living tissues [in vivo continuously and dynamically for up to several weeks. In addition, at the end of the experiment, tissue samples can be easily excised for many tests such as histology, immunohistochemistry, and molecular biology.One of the current areas of research focus in bone tissue engineering is vascularization techniques. The key to survival and function of tissue-engineered bone after implantation in the body is whether it can quickly obtain sufficient blood perfusion. To carry out research on provascularization of tissue-engineered bone, it is necessary to establish objective methods for the detection and observation of vascularization. Currently, the two main types of observation methods for microvessels are  tissues . Tissue  tissues . BecauseBased on this, we constructed a dorsal skinfold window-chamber model in nude mice. Moreover, for the requirement of accuracy in vessel counts and the need to calculate blood perfusion in OECs-DBM scaffolds, we gave tail vein injections of Texas Red-Dextran for labeling plasma in nude mice. Our results indicate that the method is more accurate and clear for counting plasma microvessels and calculating scaffold blood perfusion. Since dextran prevents erythrocyte and platelet aggregation, reduces blood viscosity, and improves microcirculation, it may have an effect on microvascular counts. We observed and compared microvascular images in the same field of view before and after the injection, and found that this dose of dextran did not affect microvascular counts. After injections of Texas Red-Dextran, microvessels not observed under the light microscope could be seen under the fluorescence microscope, presumably because the microvessels were too fine in diameter and could not be easily distinguished from the background. It is obvious that the model injected with Texas Red-Dextran observes the fluorescent blood vessels clearly, with a strong contrast with the background, and the blood vessels are counted accurately, which reduces the error of the researchers’ manual counting, and has more advantages than simply observing under a light microscope.in vitro dynamically perfusion-treated prevascularized OECs-DBM scaffold, and its pro-vascularization ability after implantation was compared with that of a statically perfused OECs-DBM scaffold. We have previously shown that a dynamic perfusion system that imparts continuous fluid shear stress to OECs on DBM scaffolds can promote spreading adhesion, proliferation, differentiation to mature endothelial cells, and three-dimensional tube formation in stromal pores via the PI3K/Akt/mTOR signaling pathway, promoting in vitro prevascularization of DBM scaffolds [in vivo dynamically perfusion-treated prevascularized OECs-DBM scaffold were able to inosculation with the recipient vessels in a certain way to rapidly establish a blood supply connection, allowing tissue-engineered bone to obtain a faster and better blood supply to the recipient region in vivo and improving the survival rate of the cells on the scaffold.In this study, the tissue-engineered product used was an caffolds . The resin vivo prevascularization methods to construct tissue-engineered scaffolds or simply tissue or cell masses of newborn animals enriched with various pro-vascular growth-related factors and active substances. For example, nano-hydroxyapatite/polyether polyurethane scaffolds were prevascularized in vivo and cultured with VEGF-rich Matrigel gel [In vivo prevascularized PLGA scaffold [in vivo prevascularized polyether polyurethane scaffolds into nude mice after 3 days of in vitro incubation in DMEM medium, which was found to increase the expression of VEGF on the scaffolds, accelerating the process of vascular fusion and the coexistence of both fusion modalities [in vitro dynamically perfused OECs-DBM scaffold preconfigured vessels are fused to the recipient vessels in an internal inosculation to obtain blood supply. Because, no green fluorescent cells of OECs were seen outside the scaffold, and the complete luminal structure of the vessel composed of OECs was visible inside the scaffold, and receptor erythrocytes were visible in it.There are few studies on the mechanism of vascular inosculation. In contrast, the study of the mechanism of inosculation of tissue-engineered products with recipient vessels has not been reported, which is one of the innovations of this study. It is generally accepted that there are two types of inosculations between the recipient vessel and the graft vessel: internal inosculation and external inosculation. Some studies suggest that vascular inosculation occurs within the graft and that the mechanism is intra-graft vascular regression, with the recipient vascular network growing in along the graft and fusing with it ,29. In cigel gel . In vivoscaffold . VEGF- ascaffold . Cellulascaffold . The grascaffold ,29. The dalities . CombineThe results of this experimental study were positive. Nevertheless, we believe that further optimization is needed. On the one hand, the rate of vascular inosculation also depends on the angiogenic process, such as the angiogenic activity of the preconstituted and recipient vessels. Therefore, vascular inosculation can be optimized by further improving the angiogenic activity of the preconstituted vessels or the recipient tissue, such as VEGF gene transfection of OECs. On the other hand, it has been demonstrated that the inosculation of preconfigured vessels with vascular buds at both ends of the recipient tissue is mainly dependent on the balance between Notch and Wnt signaling pathways, which control the stability of the neovascular network . Therefoin vitro dynamic perfusion culture of prevascularized OECs-DBM scaffolds resulted in faster and more adequate fusion with the recipient vessels in an internal inosculation to obtain blood perfusion to the recipient area.In summary, this study successfully constructed a dorsal skinfold window-chamber model and established its method for counting microvessels and calculating scaffold blood perfusion volume in combination with Texas-red dextran-labeled plasma. In addition, we demonstrated that


In the last two decades, an increasing number of so-called molecular-targeted therapies have become available for the treatment of patients with advanced malignancies. These drugs have included inhibitors of proteins in the MAPK pathway, such as BRAF and MEK inhibitors, which are characterized by a distinct toxicity profile. The eye is particularly susceptible to adverse effects due to MEK inhibitors, and the term MEKAR (MEK-inhibitor-associated retinopathy) indicates the presence of subretinal fluid, mimicking central serous chorioretinopathy (CSC). The pathogenesis of the retinal alterations related to MAPK pathway inhibitors is still unclear, and questions are still open. The present study aims to assess the presence of retinal pigment epithelium alterations as predictive parameters for retinal toxicity, analyzing, at the same time, the chorioretinal vascular network in patients undergoing BRAF/MEK inhibitor treatment for different malignancies. V600), while others have more pleiotropic activity  in), which in turn activates a basolateral ionic Cl- channel, depolarizing the basal membrane and producing the EOG’s recognizable light rise. The light peak:dark trough ratio is the common way to express this as a ratio of “light peak to dark trough.” The standing potential of the entire RPE is altered by an aberrant EOG, and the RPE’s ability to pump fluid out of the sub-retinal region is disrupted, leading to the buildup of serous SRF ,25,26,27Previous studies have described the retinal lesions associated with MEK inhibition treatment as central serous-like chorioretinopathy (CSCR) ,29. It hOtherwise, we observed a low incidence (one eye) of MEKAR in our patient group, as compared to other cohorts, and no other types of ocular adverse events, as reported in the literature . As descAnother explanation for the failure of the retinal cells is that an autoantibody attack against certain RPE epitopes may compromise the RPE pumping function, with a consequent alteration of the EOG. Paraneoplastic retinopathies (PRs), such as cancer-associated retinopathy (CAR) or melanoma-associated retinopathy (MAR), represent retinal disorders mediated by autoimmune mechanisms and are associated with serum anti-retinal autoantibodies .Sawyer was the first to describe CAR . The etiMAR was described for the first time by Berson and Lessell . This isFurthermore, the presence of anti-RPE antibodies against the RPE protein, bestrophin, was described in a patient with metastatic choroidal melanoma and vitelliform paraneoplastic retinopathy, characterized by an abnormal EOG .There are few data on the potential prevalence of these autoantibodies in individuals, and there is currently no gold standard for the diagnosis.In patients with presumed PR, the presence of autoantibodies can predict the presence of an underlying neoplasm , but their diagnostic value is not fully understood ,43,44.Considering the rapid onset of the profoundly abnormal EOG and the dramatic decrease in the light peak:dark trough ratio in all populations, we hypothesize that panretinal dysfunction of the RPE can be related to the direct toxicity of the oncological treatment (by the blockade of the MAPK pathway) and, consequently, represents an important predictive parameter for retinal alteration. The low incidence of serous retinopathy observed in our population compared with other studies could be related to the phenomenon of paradoxical MAPK pathway activation caused by BRAF inhibitors. The unremarkable OCT-A analysis suggests no role for the retinal and choriocapillaris vasculature.


Deep brain stimulation (DBS) has emerged as an invasive neuromodulation technique for the treatment of several neurological disorders, but the mechanisms underlying its effects remain partially elusive. In this context, the application of Transcranial Magnetic Stimulation (TMS) in patients treated with DBS represents an intriguing approach to investigate the neurophysiology of cortico-basal networks. Experimental studies combining TMS and DBS that have been performed so far have mainly aimed to evaluate the effects of DBS on the cerebral cortex and thus to provide insights into DBS’s mechanisms of action. The modulation of cortical excitability and plasticity by DBS is emerging as a potential contributor to its therapeutic effects. Moreover, pairing DBS and TMS stimuli could represent a method to induce cortical synaptic plasticity, the therapeutic potential of which is still unexplored. Furthermore, the advent of new DBS technologies and novel treatment targets will present new research opportunities and prospects to investigate brain networks. However, the application of the combined TMS-DBS approach is currently limited by safety concerns. In this review, we sought to present an overview of studies performed by combining TMS and DBS in neurological disorders, as well as available evidence and recommendations on the safety of their combination. Additionally, we outline perspectives for future research by highlighting knowledge gaps and possible novel applications of this approach. Transcranial Magnetic Stimulation (TMS) is a non-invasive neurophysiological technique that enables the investigation of the functional state of the cerebral cortex ,2,3,4. TIn addition to stimulating superficial cortical layers, TMS has been shown to determine a more widespread modulation of cortico–subcortical networks ,13,14. TIn this context, the combination of TMS and DBS may be a useful approach to simultaneously investigate cerebral cortex and deep brain structures, as well as their mutual cortico–subcortical connections . SeveralIn the present review, we first outline the results of previous studies reporting the combination of TMS and DBS in different neurological disorders. Then, following a brief report about evidence and recommendations on safety issues, we examine and discuss the potential benefits of this combined approach. Finally, we mention the current knowledge gaps in the field, highlighting some possible perspectives for future research.To date, most of the experimental studies applying TMS in patients treated with DBS aimed to provide insights into the mechanisms underlying DBS, improving the understanding of its effects ,30,31. FIn these studies, the stimulation itself was not associated with changes in motor thresholds ,40,41,42Moreover, some studies in PD patients investigated the effects of DBS on SICI, a paired-pulse TMS measure reflecting the activity of GABA-A-ergic intracortical circuits ,60, whicThe effects of DBS on SAI and LAI in PD patients were investigated in a single study, where modulation of both measures with STN-DBS was reported . In moreMoreover, multimodal approaches combining TMS-DBS with neurophysiological techniques for the study of cortical activity, such as electroencephalography (EEG) and magnetoencephalography, represent a promising tool to investigate the effect of DBS stimulation on cortical areas. To date, only one study has evaluated the effects of STN-DBS in PD patients using a TMS–EEG approach , showingHence, based on the available evidence, DBS targeting STN and GPi can modulate different inhibitory intracortical circuits in M1, as well as sensorimotor integration at the cortical level in PD patients, as measured by different TMS protocols. The observed differences in SICI and SP between patients treated with STN-DBS and GPi-DBS have mainly been related to the different therapeutic effects of the stimulation ,38. HoweStudies in patients with dystonia treated with GPi-DBS showed a DBS-induced modulation of M1 excitability and intracortical inhibitory circuits. A first study by Kühn et. al. , reporteIn patients with dystonia, a decreased SICI has been described by several studies, reflecting reduced inhibition within the motor cortex ,66,67. TThe major findings of studies applying TMS and DBS alone, as well as their combined application in patients with dystonia, have been discussed in detail in a recent review by Udupa et al. .To date, only two studies have been performed to explore the effect of DBS of the Ventral Intermediate nucleus (VIM) of the thalamus in patients with essential tremor (ET) using a combined TMS-DBS approach . By applIn a previous study by the same group , patientTo date, only one TMS study was performed in a small group of patients with drug-resistant epilepsy treated with bilateral DBS implantation in anterior nuclei of the thalamus (ANT) . In thesOverall, these studies provide relevant information on abnormalities in cortical excitability, connectivity, and plasticity in several neurological conditions, expanding our knowledge of their pathophysiology. More research should be conducted on additional neuropsychiatric conditions where DBS is emerging as a therapeutic opportunity, such as Alzheimer’s disease and other dementias.Another potential experimental approach is the application of patterned TMS protocols to assess if DBS stimulation can modulate cortical synaptic plasticity. This could be particularly important in the study of neurological disorders with well-described abnormalities in several types of experimentally induced cortical plasticity, such as PD and dystonia ,68,69. IThe induced plasticity shares several features with associative long-term potentiation and long-term depression described in the hippocampus, such as its associativity, long duration, and interaction with motor learning ,74,75.RTMS consists of the delivery of repetitive magnetic stimuli that induce persistent inhibitory or facilitatory changes in cortical excitability depending on the frequency and the pattern of the stimuli .PAS consists of the pairing of peripheral electrical stimuli of the median nerve with single TMS pulses applied over the contralateral M1 at specific time intervals and induces spike-timing-dependent plasticity in the motor cortex ,74,76. PAlthough the mechanisms underlying DBS’s effects are still unclear, the modulation of cortical and subcortical synaptic plasticity could be responsible for the clinical benefits of the stimulation. Evidence from animal models and imaging studies in humans suggest the existence of long-lasting effects on brain activity, thus supporting a DBS-induced modulation of brain plasticity ,78. MoreIn a study performed on PD patients treated with STN-DBS, the PAS protocol was applied with the stimulator switched on and off and with and without the acute administration of levodopa . PAS indConversely, in a group of patients with primary generalized dystonia, the PAS protocol was applied when DBS was switched on and induced a decrease in motor cortical excitability with respect to both the switched-off condition and the healthy controls , thus suIn another study, with the aim of evaluating changes in cortical plasticity over time, PAS was applied in dystonic patients before and 1, 3, and 6 months after GPi-DBS surgery , with thThe pairing of TMS and DBS stimuli may represent a novel and intriguing method to induce cortical synaptic plasticity. In order to produce spike-timing-dependent plasticity in the cortex, the coupling of magnetic and electrical stimuli should be performed at ISIs close to, or corresponding to, the time needed for neural signals to travel between the stimulated structures . TransmiIn a first study in patients with PD, an increase in MEP amplitude was described at ISIs of 3 and 23 ms between conditioning STN-DBS stimuli and an M1 single-pulse TMS . Based oIn another study in PD patients, DBS stimuli delivered in the STN were repeatedly coupled with single TMS pulses applied over M1 at different ISIs . In lineSimilarly, in patients with cervical dystonia treated with bilateral DBS of the Gpi, DBS pulses were paired with single-pulse TMS at different ISIs . The tesDBS–TMS coupling could represent an experimental approach to assess TMS-induced effects on the activity of basal ganglia and thalamus by recording LFPs with DBS leads. Magnetic stimuli delivered with single-pulse TMS are thought to affect the most superficial layers of the cerebral cortex . Direct The recording of LFPs for deep brain structures with DBS electrodes may thus provide insights on cortico–basal connections and their contribution to DBS’s effects .The application of TMS in patients treated with DBS raises several safety issues regarding the potential of magnetic field pulses to induce electrical voltages and currents in DBS electrical components, such as intracranial leads, subcutaneous wires, and implantable pulse generators. In turn, this might lead to DBS system malfunctions and to potentially harmful brain damage. This topic was addressed by a first Expert Consensus in 2009 , promoteTo further address this issue, Magsood et al.  measuredAccordingly, although the application of TMS in DBS patients is overall considered a safe approach, several factors should be considered, including: (i) the position of the TMS coil with respect to the DBS leads and subcutaneous extension wires; (ii) the distance between the TMS coil and the implantable pulse generator; (iii) the presence, number, and direction of loops in extension wires. The higher risk of inducing high voltages in the DBS system is associated with TMS coil placed directly over DBS leads and the TMS-induced current (which is perpendicular to the coil itself) aligned with the DBS lead or centered over extension wire loops ,91,92. CAlthough the use of E-Field estimation and imaging techniques for guiding the delivery of TMS is considered a safer approach with respect to non-navigated TMS, there is currently no evidence suggesting its benefits in terms of safety in patients with DBS . Moreover, as new DBS systems will become available, the aforementioned issues should be evaluated according to the characteristics of the stimulating device . To date, the safety of the application of rTMS was assessed only in one patient with OCD treated with bilateral DBS of the nucleus accumbens and anterior arm of the internal capsule . In theiOnly a few studies were performed combining rTMS with other implanted electrical devices. Phielipp et al. , reporteHowever, despite the lack of major adverse effects, the results of these studies cannot be generalized to the application of rTMS in patients with DBS, and more evidence assessing the safety of this procedure is required.Recent advances in DBS technology are offering new perspectives for the study of abnormal neural activity of deep brain structures in several neurological disorders and for the understanding of mechanisms underlying DBS effects . ImportaAs discussed above, these recordings potentially allow for the evaluation of TMS-induced effects on deep brain structures and a better characterization of connections between DBS targets and cortical areas. Furthermore, DBS is currently under investigation as a treatment for other neuropsychiatric disorders , and several deep brain structures, as well as cortical areas, are emerging as new potential targets . As moreMoreover, an important issue that should be addressed concerns the reproducibility and clinical effect of TMS and DBS stimuli coupling as a plasticity-inducing method.As discussed above, several safety concerns are currently limiting the combined TMS–DBS application . ImportaAlthough OCD is an approved indication for DBS therapy , to dateConcerning movement disorders, although DBS targeting the VIM of the thalamus is an approved treatment for PD patients with severe tremor, studies combining TMS with DBS have never been performed in these patients. A further potential development of the TMS–DBS combined application could be represented by multimodal approaches combining other neurophysiological techniques, such as EEG , magnetoExperimental studies combining TMS and DBS have provided insights into the modulation of cortical excitability and plasticity induced by DBS, particularly in movement disorders. These effects have emerged as putative mechanisms underlying DBS effects and have provided important clues on DBS’s mechanisms of action. However, combining TMS and DBS is currently limited by several safety concerns, and the application of this experimental approach is below its true potential. With the advances in DBS technology and with the identification of new targets, a deeper understanding of DBS effects will become crucial for its clinical application. Moreover, the combined neuromodulation offered by the repetitive pairing of TMS and DBS stimuli could represent a novel therapeutic approach whose clinical relevance needs to be clarified.


In the last two decades, considerable interest has been shown in understanding the development of the gut microbiota and its internal and external effects on the intestine, as well as the risk factors for cardiovascular diseases (CVDs) such as metabolic syndrome. The intestinal microbiota plays a pivotal role in human health and disease. Recent studies revealed that the gut microbiota can affect the host body. CVDs are a leading cause of morbidity and mortality, and patients favor death over chronic kidney disease. For the function of gut microbiota in the host, molecules have to penetrate the intestinal epithelium or the surface cells of the host. Gut microbiota can utilize trimethylamine, N-oxide, short-chain fatty acids, and primary and secondary bile acid pathways. By affecting these living cells, the gut microbiota can cause heart failure, atherosclerosis, hypertension, myocardial fibrosis, myocardial infarction, and coronary artery disease. Previous studies of the gut microbiota and its relation to stroke pathogenesis and its consequences can provide new therapeutic prospects. This review highlights the interplay between the microbiota and its metabolites and addresses related interventions for the treatment of CVDs. According to the World Health Organization (WHO), cardiovascular diseases (CVDs) cause the deaths of 17.9 million people per year, corresponding to 31% of all deaths. Of these, 85% are directly associated with stroke and heart attack. Arterial hypertension, coronary artery disease (CAD), and cardiomyopathies that reinforce heart failure and cerebrovascular diseases at the end phase are typically categorized as CVDs under non-communicable conditions . DyslipiThe human intestinal microbiota comprises more than 10 trillion microorganisms, including bacteria, archaea, viruses, protozoa, and fungi. A healthy microbiota consists primarily of four groups of bacteria, namely Actinobacteria, Firmicutes, Proteobacteria, and Bacteroides, and they continuously adapt these to lifestyle changes . The humThe gut microbiota interacts with the host through the intestinal mucosal surface, and the function of the intestinal epithelial barrier is maintained through several functions of a well-balanced gut microbiota, such as the restoration of tight junction protein structure, mucin gene upregulation, and inhibition of epithelial cell binding with pathogenic bacteria. Intestinal wall edema may decrease intestinal blood flow in the context of compromised cardiac and/or renal function, which may occur due to the structural disruption of the mucosal epithelial barrier and increased permeability . DisruptThe synthesis of trimethylamine N-oxide (TMAO) and the development of cardiovascular risk exhibit another dimension to this dynamic activity, i.e., the interplay between the intestinal microbiome and the human host that occurs through the interaction of dietary intake  with the intestinal microbiota, leading to the production of metabolites that may serve as cardiac disease boosters . Given tThis review highlights several recent advances in our understanding of the gut microbiota’s role in the development of atherosclerosis and associated severe CVD complications. It also addresses strategies for targeting the gut microbiota that contribute to the generation of TMAO for the potential prevention and treatment of CVD as well as the role of gut microbiota in CVD and potential corresponding interventions.The gut microbiota has several effects on the host Table 1.via the bile acid route and trimethylamine  ratio remains the same in subjects with CVD  and choline in foods into TMA. L-carnitine is thought to be converted to γ-butyrobetaine in a second step. TMA is oxidized into TMAO in the liver. According to new data, high circulating levels of TMAO are linked to an increased risk of CVD and mortality.Many variables contribute to this elevated risk, including changes in cholesterol and bile acid metabolism and the activation of inflammatory pathways. Higher levels of TMAO in the arteries increases cholesterol deposition from the circulation, contributing to atherosclerosis. The inflammatory reaction is a key contributor to the progression of renal disease and/or the development of metabolic syndrome and/or type 2 diabetes .via coexistence with the host, collectively forming the microbiota. Several microorganisms colonize host organisms to survive. Generally, the microbiota that colonizes the gastrointestinal tract (GIT), specifically the colon, is termed the primary anaerobic microbiota. Nutrients are digested by colonies of microbes in the intestine by proteolytic and saccharolytic pathways , which is an anti-diabetic, antiatherogenic, anti-obesogenic, hypolipidemic, and immunomodulatory fatty acid . AccordiA healthy gut microbiota as required for optimal homeostasis places the gut mucosal immune system in a difficult position as it must tolerate beneficial commensals while preventing pathogen overgrowth. A two-tiered mucus layer, which keeps luminal microorganisms away from epithelial contact, is a fundamental mechanism of antimicrobial defense, especially in the large intestine. Mucus comprises a variety of mucin glycoproteins released by goblet cells in the intestine and can extend up to 150 meters from the colonic epithelium .The gut microbiota has been shown to promote the formation of antimicrobial proteins (AMP) such as cathelicidins, C-type lectins, and (pro)defensins by host Paneth cells through a PRR-based pathway involving its structural components and metabolites . The PRRThe gut microbiota has also evolved a strategy to prevent the overgrowth of pathogenic strains through the generation of local immunoglobulins. The gut microbiota, particularly Gram-negative bacteria such as Bacteroides, has been found to stimulate intestinal dendritic cells (DCs), causing plasma cells in the intestinal mucosa to secrete IgA , effector and regulatory T cells, IgA-producing B (plasma) cells, Group 3 innate lymphoid cells, and resident macrophages and DCs in the lamina propria are all immune system components and cell types that participate in immunomodulatory the process .Many studies have found that dietary therapies can significantly lower cardiovascular risk . A MeditRoseburia and E. rectale were found to be associated with differences in the proportion of dietary carbohydrate content. The growth of beneficial commensal bacteria is promoted by fiber-rich diets and prevents the development of known opportunistic pathogens  in carotid atherosclerosis patients  and healthy participants, with some consistent findings but significant variance between investigations Table 3.Current data on the gut microbiota and its connection to disease pathogenesis show potential for its therapeutic targeting. Drugs targeting the microbiome are still far from being manufactured but newly developed drugs provide opportunities for the treatment of stroke. Previous publications reported that TMAO was inhibited by antibiotic use, whose administration over an extended period has negative effects such as the development of clostridium colitis . However;Although therapeutic alterations in gut microbiota composition can improve host well-being, significant abrupt changes within the gut milieu through the use of antibiotics in humans during the first 6 months of life is associated with childhood obesity . SimilarBy modifying the SCFAs of diastolic and systolic BP, CVD risk can be reduced and BP controlled. Testing in humans revealed that butyrate works as a helper in lowering diastolic BP DPB; . During A place for SCFA where it has more effect on the metabolic system. The relationship between strong animal and epidemiological shows opposite when compared to weight and dietary fiber. Recent studies have provided more knowledge about the role of SCFAs and found that acetate accelerates the production rate and regulates central appetite . This prSoluble gut fiber decreases the rates of TMAO and TMA metabolism to 40.6% (TMA) and 62.6% (TMAO); it is significantly related to SCFA production and decreased serum lipids . On the via the coordinated modulation of tight junction proteins that govern the intracellular molecular pathways between the lumen and the hepatic portal system. The movement of bacteria and/or their cell wall components is linked to hyperglycemia and increased gut permeability, which triggers an inflammatory process linked to obesity and insulin resistance  and expression of proinflammatory genes in the liver were linked to these benefits. Given the growing importance of maintaining a functional physical barrier between luminal bacteria and the host immune system in the gut, well-designed studies in humans are needed to better understand SCFA’s involvement in gut barrier function.SCFAs have been linked to a reduction in appetite and calorie intake, which may protect against diet-induced obesity. Incorporating SCFAs into the diet of rats, on the other hand, has been shown in many experiments to have no influence on food consumption . Similarin vitro models of enteroendocrine cell lines  and peptide YY (PYY), SCFAs may lower energy intake by promoting the production of these anorectic hormones . This imll lines .via FFAR2 according to these studies. High levels of SCFAs in the lower intestine have also been hypothesized to control energy intake via gut-brain neuronal pathways. For example, via FFAR3  in urine, which was secreted for 24 hours. This component is responsible for the high levels of protein fermentation found in CKD . Uremic Collinsella in a large number of patients with symptoms of atherosclerosis. On the other hand, Eubacterium and Roseburia were abundant in healthy individuals  in the primary stages of CKD, one quantitative and the other qualitative. Thus, its formation and metabolic activities alter the microflora in CKD, making this a topic of interest in the field of nephrology. These changes include intestinal conduction and consumed protein absorption, reduced dietary fiber intake, oral iron treatment, and heavy use of antibiotics .Combustibility and uremic toxins play a leading role in the pathophysiology of atherosclerosis and other complications involved in CKD . The invEnterobacteria, Clostridiaceae, Pseudomonadaceae, and Bacteroides increase in number, while beneficial species such as Lactobacillus, Bifidobacteria, and privateness decreased  is the primary cause of lipid buildup in atherosclerotic lesions. Consequently, a change in lipid metabolism favoring increased LDL and decreased high-density lipoprotein (HDL) levels, which aids cholesterol efflux and prevents its buildup, is an essential pathophysiological component of atherosclerosis progression. Additionally, chronic inflammation is a factor that has an equal, if not greater, role in the development of this disease .;A wealth of information suggests that mitochondrial damage, which causes oxidative stress and local inflammatory responses, plays a role in the initiation and development of atherosclerosis . DespiteRemarkably, information has been gained that relates the dysbiosis of the gut microbiota to the pathways behind insulin resistance, lipogenesis, fat accumulation, mitochondrial dysfunction, and systemic or local inflammation . Interac)SCFAs can also cross the gut barrier and attach to receptors on other cell types, such as hepatocytes, adipocytes, and muscle cells, activating the AMPK pathway and improving glucose and lipid metabolism. Such metabolic outcomes of the interactions between the gut microbiota and the host appear to be significant not only in the pathogenesis of CVD but also in cancer biology. In fact, the metabolic condition of the tumor microenvironment can influence the anti-cancer immunity of tumor-infiltrating lymphocytes TILs; . For exaAkkermansiamuciniphila in their stomach, according to studies  and a decrease in Bacteroidetes. Patients with type 2 diabetes had a lower number of Firmicutes and a non-significant rise in Bacteroidetes and Proteobacteria , CKD-specific treatment interventions such as iron supplementation and phosphate binders , and dievia G protein-coupled receptors (GPCRs)  are one prospective factor contributing, as they have the ability to regulate blood pressure  (GPCRs) . Propion (GPCRs) . However (GPCRs) . To bett (GPCRs) . The hyp (GPCRs) .Firmicutes and Bacteroides in the intestinal microflora, the two most prevalent groups in the normal flora. Dysbiosis in IBD, particularly Crohn’s disease (CD), has been linked to an increase in the Enterobacteriaceae family, according to some research findings  patients is associated with decreases in commensal bacteria variety, with the preponderance of the reduction appearing in findings . Five bater XIVa . Unaffecter XIVa . Becauseter XIVa . In thesbacteria . This prbacteria . Malfuncbacteria .Bacteroidetes and Firmicutes in the majority of research in both humans and animal models, with a reduction in Bacteroidetes and an elevation in Firmicutes. This ratio has been linked to body weight and fat deposition, indicating that obese people have a higher disproportionate ratio of these bacteria -related dysbiosis is marked by an increase in evotella . In non–eability . Elevateeability . It is ueability . The miceability .Proteobacteria, Bifidobacteria, Prevotella, and SCFA production rates have decreased, whilst Firmicutes, Bacteroidetes, Enterobacteriaceae, and Fusobacteria have increased (Akkermansia muciniphila and Fusobacterium nucleatum, in CRC tissues (F. nucleatum is also linked to an increase in CRC tumors and lymph node cancer. The structure and luminal numbers of dominant microbial species seen in CRC-associated dysbiosis largely depend on pathogenicity and tumor stage/status, according to the findings. Between patient populations with polyps and those with tumors, substantial variations in mucosal and fecal microbial configurations were found, with the most major changes being Enterobacteriaceae, which was elevated in the mucosa of patients with tumors compared to those with polyps, and Bacteroidetes, which was expanded in CRC tissues with tumor cells compared to those without tumors (Patients with CRC have a general dysbiosis pattern, which includes a decrease in butyrate-producing bacteria and a rise in the number of multiple potentially dangerous microorganisms. According to many studies, ncreased . Various tissues . Both oft tumors .The gut microbiota is a novel topic of research interest with significant applications in human health with respect to the development of innovative diagnostic and therapeutic tools for preventive and curative outcomes. Few studies in humans have investigated the intestinal microbiota’s causative relationships, putative pathways, and metabolites in the context of host disease. Recent molecular and biochemical studies have allowed diverse microorganisms to be detected and categorized and facilitated the analysis of their genomes and metabolites. In particular, genome-scale metabolic models can guide our understanding of the function of individual organisms within the gut microbiota and the role of the microbiota overall since the inter-individual variability of the gut microbiota contributes to different treatment responses and perspectives.Our mechanistic understanding of how the gut microbiota transforms dietary and endogenous molecules into metabolites shared with peripheral organs and tissues in the host needs substantial expansion. Although the emergence of high-throughput sequencing technologies and bioinformatics over the next decade will inevitably aid in exploring the applicable biological mechanisms, the end of the metabolic pathways sector of the system and the host targets that identify them make up the fascinating puzzle pieces required for the next step in this growing field. Further mechanistic experiments may result in the development of TMAO as a novel biomarker for the primary prevention of CVD. This could lead to a change in the conventional risk factors for CVD and modulation therapies directly targeted at the intestinal microbiota. Metabolic models at the genome scale are statistical descriptions of the metabolic ability of the microbiota that can simulate differences in metabolic system function among different organisms by incorporating knowledge of the gut microbiota’s metabolism.It is expected that these technological advances will promote the transition from correlation experiments to mechanistic insights, resulting in the development of novel diagnostic tests and therapeutics in the near future. Further research is needed to fully explore the processes underlying host-microbiota interactions to shed light on the biological effects of direct or indirect manipulation of the gut microbiota.MMR, FI, and AAM: Wrote the manuscript; MHR, MSR, MI, and AK: Searched literatures; PS, SM, TE, and MA: Illustrated figures and tables; FW, RI, and TT; Edited the manuscript; AAM and SC: Designed and supervised the review. All authors finally revised and approved for submission of the final version of the manuscript.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.


The necessity to include plants as a component of a Bioregenerative Life Support System leads to investigations to optimize plant growth facilities as well as a better understanding of the plant cell membrane and its numerous activities in the signaling, transport, and sensing of gravity, drought, and other stressors. The cell membrane participates in numerous processes, including endo- and exocytosis and cell division, and is involved in the response to external stimuli. Variable but stabilized microdomains form in membranes that include specific lipids and proteins that became known as (detergent-resistant) membrane microdomains, or lipid rafts with various subclassifications. The composition, especially the sterol-dependent recruitment of specific proteins affects endo- and exo-membrane domains as well as plasmodesmata. The enhanced saturated fatty acid content in lipid rafts after clinorotation suggests increased rigidity and reduced membrane permeability as a primary response to abiotic and mechanical stress. These results can also be obtained with lipid-sensitive stains. The linkage of the CM to the cytoskeleton via rafts is part of the complex interactions between lipid microdomains, mechanosensitive ion channels, and the organization of the cytoskeleton. These intricately linked structures and functions provide multiple future research directions to elucidate the role of lipid rafts in physiological processes. However, the provision of edible biomass is certainly the most sought-after benefit of plant growth in space ..47].The level of membrane cholesterol is important for the structure and stability of dense microdomains. A significant increase in the cholesterol content is a marker of the increased rigidity of lipid rafts that reduces membrane permeability. The regulatory role of sterols in membrane structure and fluidity and the assembly of specific proteins will affect cell responses to abiotic stress and microgravity ,54,77. TStreptomyces filipinensis)—is an antibiotic that is strongly fluorescent with a maximum emission at 482 nm (λex = 340 nm) upon binding to sterol-containing areas of cell membranes. Filipin fluorescence is the established tool for sterol visualization in biological membranes [Fluorescent marker of sterols—filipin naphthalene), is a fluorescent, lipophilic probe and is widely used to study the structure of biological membranes  in additThe dynamics of the Lo and Ld phases of the CM under clinorotation were examined using laurdan as an imaging probe ,96, deveThe expansion of the Lo areas  indicateThe significantly increased cholesterol content in lipid rafts and their increased density under clinorotation suggest changes in the associated proteins. Altered CM permeability is likely to affect cell metabolism as a response to mechanostimulation. These data suggest that clinorotation does not serve as a substitute for microgravity but that plants respond to enhanced mechanostimulation. This notion supports the observed effect of hypergravity on membrane lipid composition and the conclusion that gravity resistance depends on lipid rafts  as well A. thaliana [Plant lipid rafts have been defined as the sterol-dependent ordered assemblies of specific lipids and proteins in the plant CM. The dependence of membrane function on their lipid composition and associated proteins can affect the activity of integral membrane proteins, including ion channels . Accordithaliana ,105,106.A. thaliana hypocotyls in space flight and Beta vulgaris roots under clinorotation than in the controls [Cortical microtubules, which regulate the movement of the cellulose-synthesizing complexes and control cellulose deposition in the cell wall ,108,109 controls ,111. Redcontrols ,113,114.controls . Cell grcontrols .Funaria hygrometrica grown under long-term slow clinorotation and in wheat plants grown in space [Oryza sativa and A. thaliana hypocotyls in spaceflight compared with ground controls [The sensitivity of the plant cell wall structure, composition, and function is well-established. ,13,117. controls ,119. Thecontrols .Chlorella vulgaris, the protonemata of Funaria hydrometrica, the statocytes of Pisum sativum, Melilotus album, and Glycine max, the microcalluses of Daucus carota and Brassica napus, as well as in the cytosol of the root hairs in Lepidium sativum and Beta vulgaris, and in the callus cell cultures of A. thaliana [2+-permeable ion channels, the efflux by Ca2+-ATPases, and Ca2+/H+ exchangers [2+-ATPase activity associated with lipid rafts [Modifications of the intracellular calcium concentration and localization were shown in microgravity and under clinorotation similar to the fluorescent calcium indicators chlorotetracycline and indo-1. Changes in the relative calcium ion content have been demonstrated in the cells of the green algae thaliana ,123,124.thaliana ,126,127.changers ,129,130.changers . An incrchangers ,133, as id rafts . The comThese prospects for further studies of membrane lipid microdomains include their participation in cell signaling and cell membrane activities as part of experiments that seek to understand the effect of gravity and mechanostimulation on basic cellular processes in biological systems. There is an additional temporal element in this notion as the lipid profile of membranes changes depending on the type of tissue, cell, and organelle ,67,135. The data and inferences described so far clearly indicate that the functional domains of membranes are critically important for signal integration and responses. We hope that this review will prompt future research on the effect of lipid rafts and membrane functions on general and gravitational physiology.


Mitochondria are eukaryotic organelles responsible for generating the main bulk of ATP, the cellular energy currency, via the process of oxidative phosphorylation (OXPHOS). The OXPHOS system is unique because it comprises subunits of dual genetic origin, encoded in the mitochondrial and the nuclear genomes. Therefore, to form the multimeric membrane-bound complexes responsible for this energy production process, proteins translated inside the organelle must be assembled in coordination with those expressed in the cytosol and imported into mitochondria by using a sophisticated import and translocation machinery. The idea that the OXPHOS system plays a role not only in ATP production but also in regulating many physiological and pathological processes has been emerging for more than 10 years. Recent evidence points to the existence of intricate quality control systems that guarantee the functionality of mitochondria, as well as the interactions of intramitochondrial and extramitochondrial factors that ultimately influence mitochondrial bioenergetics. For these reasons this Research Topic is a timely release, covering emerging concepts relating to the structure, function, and regulation of the OXPHOS system. In addition, the Research Topic also presents novel technological approaches to unravel the yet unknown intricacies involving this group of protein complexes as well as new mechanisms or pathways linking OXPHOS dysfunction and pathological states.Guitart-Mampel et al. analyze the role of inorganic polyphosphate (polyP) in bioenergetics by using wild-type and MitoPPX SH-SY5Y  via a thorough analysis of the changes in cell physiology, proteome and metabolome. Two key metabolic mitochondrial pathways (OXPHOS and TCA cycle) were affected by deficiency in polyP. This observation could be linked to a regulatory role of polyP in processes altered in neurodegenerative disorders, such as reactive oxygen species (ROS) production, apoptosis, inflammation, or energy metabolism. Illescas et al. explore mitochondrial function within a broader cellular context, depicting how cytoskeleton dynamics is related not only to mitochondrial trafficking, dynamics, and apoptosis but also to biogenesis and metabolism. Interestingly, they report novel findings of actin filaments located outside and inside mitochondria and the relevance of gelsolin (one of the most abundant actin-binding proteins) to mitochondrial function. Other articles in the Research Topic offer an updated view of key molecular pathways inside mitochondria. Padavannil et al. explore the intriguing question of why accessory subunits of Complex I (CI) have been added during evolution to the fourteen conserved core subunits. To explain the evolutionary and functional reasons for these additions, they used a combination of available structural information from CI assembly, subunit knockout, knockdown, and mutagenesis, and clinical studies. As a result of this analysis, they propose more sophisticated molecular functions for each of the accessory subunits, including, for example, assembly coordination, scaffold for protein localization to the cristae, response to ROS generation and sensors for energy supply/output. Eaglesfield and Tokatlidis provide an updated overview concerning the structure and mechanisms of protein insertion into mitochondria, highlighting the most exciting features of the various molecular machineries conducting protein translocation and insertion . Den Brave et al. summarized the most recent and compelling insights on protein quality control mechanisms at the mitochondrial surface. They describe the current molecular pathways by which cells can survey and cleanup the mislocalization of mitochondrial proteins and protein blockages of the mitochondrial import channel in order to ensure optimal mitochondrial function.This Research Topic comprises thirteen contributions, including nine reviews, one perspective and three original research articles that highlight relevant new aspects influencing mitochondrial OXPHOS fitness. Pavez-Giani and Cyganek present the latest advances in the use of human induced pluripotent stem cells to study mitochondrial cardiomyopathies. They analyzed different reported iPSC-CM models used to study a range of mitochondrial genetic mutations and their characteristics. They additionally describe the general limitations of this approach and different strategies to overcome them. Cabrera-Orefice et al. summarize the most relevant aspects of Complexome Profiling. This resolutive approach combines the separation of membrane complexes by native electrophoresis, size exclusion chromatography, or density gradient centrifugation with proteomic mass spectrometry analysis. This technique has proven its usefulness in evaluating the inventory, abundance, and arrangement of OXPHOS Complexes and related factors in health and disease. The authors give examples of different uses for this technical approach and discuss the limitations, improvements, and the use of Complexome Profiling to complement, for example, structural methods. Finally, Robinson et al. present an elegant original research article illustrating the application of carbonate extraction of mitochondrial membrane proteins, coupled to mass spectrometry, to investigate OXPHOS structural defects. In this way, they generated membrane association profiles for >800 mitochondrial proteins and clustered them into 6 different groups based on resistance to carbonate extraction at different pH Using Complex III (CIII) knockout cell lines as an example, they used this technique to assess the destabilization of protein associations within the mitochondrial membranes induced by CIII assembly defects.An important focus of this Research Topic has been to highlight new experimental approaches that can be implemented to uncover different aspects of mitochondrial biology. Mitochondrial disorders affect various tissues and organs, and developing physiologically relevant cellular models is critical to understanding the basis of their pathology. Zhang et al. link mitochondrial dysfunction and severe liver disease. Their review discusses how liver dysfunction impacts mitochondrial fitness and consequently which mitochondrial parameters could be used as a hallmark of liver disease. They further define novel methodologies for assessing mitochondrial function in this context and propose strategies to reverse the metabolic reprogramming observed in advanced liver disease. In their perspective article, Flønes and Tzoulis evaluate the role and influence of OXPHOS in idiopathic Parkinson’s disease (PD) neurodegeneration. They consider different aspects of OXPHOS dysfunction in PD patients to enlighten the nature of this defect in the brain. More specifically, they explore the discrepancies found in the OXPHOS phenotypes of PD patients, possible molecular causes for the defects, links to other known hallmarks of PD, such as alpha-synuclein, and the potential downstream impact of OXPHOS dysfunction in PD pathology. Chowdhury et al. summarize the most recent insights into the role of released mitochondrial nucleic acids and immune system activation. They provide a comprehensive review of the main pathways involved in nucleic acid release from mitochondria, sensing mechanisms, and the consequences of these molecular processes on human health. They point out how mitochondrial RNA and DNA release may play an essential role in critical diseases such as autoimmune disorders and neuroinflammatory diseases. Interestingly, mitochondrial gene expression requires approximately 25% of the mitochondrial proteome, highlighting the complexity and relevance of this process for mitochondrial physiology. Wang et al. present a thorough review analyzing the connection between mitochondrial translation and disease. They review the different molecular steps in the process and the known mutations that affect these steps. Furthermore, they discuss the possibility of different regulatory mechanisms mediated by microRNAs, as well as the coordination between cytosolic and mitochondrial translation. Finally, Jennings et al. contributed an original research article describing the molecular consequences of DNAJC3 mutations associated with a multisystemic neurological disorder and diabetes. Disruption of this Endoplasmic Reticulum (ER) BiP co-chaperone leads to alteration of lipid and cholesterol metabolism, resulting in ER stress, activation of the unfolded protein response (UPR), β-amyloid accumulation, and ultimately an alteration of the OXPHOS system. Interestingly, the abundance of OXPHOS subunits and, concomitantly, mitochondrial respiration rates were increased in these mutants, indicating a possible pro-survival mechanism triggered by ER-stress.The last group of articles uncovers new concepts related to mitochondrial dysfunction and disease. In conclusion, this Research Topic of articles summarizes and describes novel molecular aspects of mitochondrial fitness, state-of-the-art technologies to study mitochondrial organization, and novel associations of mitochondrial dysfunction to diseases. It provides an update on the most relevant insights into mitochondrial pathophysiology, setting the path to bringing discoveries into current experimental and clinical practices.


Tendinopathy has a high incidence in athletes and the aging population. It can cause pain and movement disorders, and is one of the most difficult problems in orthopedics. Animal models of tendinopathy provide potentially efficient and effective means to develop understanding of human tendinopathy and its underlying pathological mechanisms and treatments. The selection of preclinical models is essential to ensure the successful translation of effective and innovative treatments into clinical practice. Large animals can be used in both micro- and macro-level research owing to their similarity to humans in size, structure, and function. This article reviews the application of large animal models in tendinopathy regarding injuries to four tendons: rotator cuff, patellar ligament, Achilles tendon, and flexor tendon. The advantages and disadvantages of studying tendinopathy with large animal models are summarized. It is hoped that, with further development of animal models of tendinopathy, new strategies for the prevention and treatment of tendinopathy in humans will be developed. Tendons are dense connective tissues that connect muscle to bone and transmit the forces created by muscles to the bones, which causes movement. Trauma, strenuous exercise, or overuse can lead to acute tendon rupture or chronic degenerative disease, resulting in pain, movement disorders and other clinical symptoms . Tendon Tendon biology is poorly understood compared to other components of the musculoskeletal system . DevelopThe pathology and pathophysiology of tendinopathy in humans is currently poorly understood, meaning that the validation of animal models is difficult. Two common and established features associated with tendinopathy in humans are histopathological changes and mechanical weakening of the tendon . The proetc.; verified small animal models can usually meet the needs of such research. The second is at the macro level, such as biomechanical modeling, optimization of surgical techniques, evaluation of new instruments or devices, etc. This type of research requires animal models to be highly similar to humans in structure and function, so large animal models, especially non-human primate models, are usually more suitable. In most cases, these two goals are not separate; both micro and macro levels need to be considered. Large animals have more prospects for application because they can be used for both microscopic and macroscopic research.The principal animals used in the study of tendinopathy include rats, mice, chickens, rabbits, sheep, horses, dogs, pigs, and so on. The research objectives of tendinopathy are stratified by two main concerns . One is This article reviews and analyzes the large animal models used in the study of tendinopathy in recent years with respect to four aspects: rotator cuff injury, patellar ligament injury, Achilles tendon injury and flexor tendon injury. The article aims to provide reference for further research.Rotator cuff injury is the most common shoulder injury. After injury, the tissue often presents with irreversible muscle atrophy, stiffness and fatty infiltration . The ideRabbits are one of the commonly used animal models in orthopedic studies. Hyman et al. presented a detailed architectural and physiological analysis of chronic tear and repair compared with age-matched control rabbit supraspinatus muscles . Previouin vitro biomechanical studies  peri-tendon fixation technique for minimally invasive surgery and then compared the biomechanics of LBMK with Kessler and percutaneous Achilles repair system techniques with a simulated early rehabilitation program .Tian et There are few studies on pigs as animal models for Achilles tendon injury. Previous studies used pigs to study the biological characteristics of Achilles tendons or collected the Achilles tendons of pigs as materials for tendon injury repair. Zhang et al. characterized the structural components, vascularity, and resident tendon cells of the porcine Achilles tendon . Lohan eAnimal models involving flexor tendons include the superficial flexor digitorum and flexor digitorum profunda tendons. The tendon healing process here is very slow due to the presence of ischemic and cell deficiency, which is consistent with the healing characteristics of tendinopathy . Flexor To understand the repair process of flexor tendon injuries, studies have used the rabbit flexor tendon injury model to detect the expression of mast cells, fibroblasts, neuropeptides  and growSheep flexor tendon injury models include flexor tendon transection, collagenase induction, and partial tendon resection to create defects. To explore the mechanism of flexor tendon injury, Biasutti et al. recorded the gene expression, and histopathology and biomechanical changes that occur throughout the superficial digital flexor tendon up to 16 weeks post-injury in a sheep surgical model . Previouversus sharp transection with a tenotomy knife (The flexor digitorum superficialis tendon of horses is a frequently injured structure that is functionally equivalent to the human Achilles tendon. Both play a key role in energy storage systems during high-speed exercise and can accumulate microdamage related to exercise and age, and are prone to rupture during strenuous activities . To studmy knife . With inThe selection of preclinical models is essential to ensure that the efficacy and safety of studied treatments is successfully translated into clinical practice. The selection of animal models requires consideration of scientific criteria, economics, and ethical issues. Indeed, the costs associated with animal rearing and management significantly influence the selection of animal species because an adequate sample size is necessary to obtain reliable results. Therefore, the selection of animal models for proof-of-concept studies needs to balance the ethical justification, cost-effectiveness, and appropriateness of the model itself, such as anatomical location, size, surgical approach, and biomechanical properties. When considering the efficacy of a new therapy, for the validity of preclinical models, the identification of appropriate controls, optimal study duration and intermediate time points, and the provision of the most in-depth analysis must be considered .Rodents are the most used animal model for the study of the genetic and molecular mechanisms of tendinopathy due to their minimal cost and ethical compliance. Rats are often used to explore the factors affecting tendon-bone healing , the molin vivo imaging analysis. The docility of rabbits allows evaluation of postoperative rehabilitation effects by immobilization or active loading. Rabbit models can also be used to evaluate the role of autologous cell therapy and regenerative medicine (Compared with small animals, large animals share many similar characteristics with humans in genetics, anatomy, physiology, pathology, and so on. Therefore, large animals are more suitable for macroscopic research on topics such as tendon biomechanics, scaffold repair technology, and surgical method optimization. The advantages and disadvantages of large animal models in tendinopathy research are summarized in medicine . Sheep aThe application of animal models has promoted the progress of tendinopathy research but, given the complexity of human tendinopathy, there are still significant differences between animal experimental models and clinical human tendon injuries. In addition, more validated animal models are needed, as no single model can answer all the questions . It is h


In our specialty, steroids are commonly used to treat laryngeal disorders, by different routes of administration; however, in many clinical conditions we still lack scientific evidence enough to prove the benefits of such treatment, as well as the most adequate doses and the best routes for administration. For some laryngeal diseases - such as the supraglottitis, the use of steroids is undisputed - precluding tracheal intubation in adults and children alike. There are some systematic reviews in the literature proving the efficacy of oral dexamethasone and inhaled budesonide or fluticasone propionate in the treatment of supraglottitisAnother precise clinical indication for steroids is in laryngotracheobronchitis, which involves subglottic edema which often times extends to the tracheobronchial tree. Symptoms of cough, stridor and dyspnea may be minimized with the use of inhaled steroids (budesonide) - considered an efficient and safe treatment.Steroid indication to prevent post-intubation stridor has also been approached by some systematic review papers and, in such clinical conditions, the intravenous route is the most utilized one. These studies show a trend towards a reduction in the number of re-intubations of newborns, proven reduction in older children, and the lack of evidence that these drugs benefit adult patientsAnother very frequent use of steroids is in the course of acute viral laryngitis, especially in people who make professional use of their voices  - singers and actors, who require a quick recovery from their symptoms to return to their professional activities as soon as possible. The steroids used in these cases are usually administered via intramuscular injection (betamethasone) or inhaledDespite better patient compliance concerning inhaled treatment, one must stress that it is not free from side effects. Inhaled steroids are commonly used in asthmatic patients, and many of them use the medication day-in day-out for many months. Drug particles, as dry powder, settle along the airway mucosae, and this may cause local irritation, characterizing a form of chemical laryngitis, peaking as inflammation of the airway mucosae. We also notice erythema, mucosal edema, thickening, leukoplasia, granulation tissue and candidiasisInhaled or intra-lesion steroids have been also used in the remission of some benign lesions of the vocal folds, such as granulomas, nodules and polyps


The development of new technologies strongly depends on the design of new materials. The combination of dissimilar materials opens a wide variety of opportunities to create composites with novel functions, properties, and applications . PolymerRheology provides crucial knowledge regarding the interaction between the different phases added to polymeric matrices and the processing of composites. Thus, the rheological characterization and computational modeling of composites provide critical information about the compatibility of the different phases and the processing of the final material. Moreover, these novel materials demand the development of innovative processing methods and technologies that can result in novel applications.One of the main challenges in the preparation of reinforced composites is obtaining uniformly dispersed fillers in the polymeric matrix. Fillers, especially in the case of nanomaterials, tend to agglomerate with a non-homogeneous distribution, which can act as defects . This scIn the case of nano-composites, the most popular techniques of fabrication include solvent processing, in situ polymerization, and melt blending , among oRheology is a powerful tool to develop new materials since it responds to the different conditions that occur in most of the above-mentioned manufacturing processes; for example, the flowing conditions during extrusion  or the vThe addition of wood particles in recycled polyethylene increases the viscoelastic moduli due to poor compatibility and weak interfacial adhesion between the two phases, which is a promising result regarding common processing technologies such as extrusion or injection molding .It was found that designing filaments of graphene-polyamide nanocomposites with steady shear viscosities of approximately 15% of the maximum printable viscosity for the desired printing conditions will be advantageous for easy material extrusion processing . Carbon Self-healing composites exhibit interesting properties such as protection against corrosion. For example, the incorporation of an aminosilane into organic polymers using sol–gel chemistry has been evaluated through thermal, mechanical, and rheological properties . ModifieBionanocomposites are an emerging field of study. PLA is one of the most promising bioplastics to replace regular plastics. However, its mechanical, thermal, and barrier properties, among others, should be improved. The addition of nanoparticles by melt compounding is a widely used technique . The rheThis Special Issue is intended to give an overview of the recent research dealing with the formulation of polymer-based nano- and micro-composites. These emerging materials have shown special properties and a wide range of applications. However, current manufacturing techniques face challenging difficulties to process these materials. The rheological characterization of composites gives critical information for their design, modeling, and fabrication.