Oscilometría: de la teoría a la práctica / Oscillometry: from theory to practice

La oscilometría es una herramienta que, poco a poco, se está abriendo paso en las consultas de neumología y alergología. Se trata de una técnica sencilla de realizar para el paciente, que, además, aporta información adicional a las pruebas de función respiratoria clásicas. No solamente nos indica la alteración que existe en la vía aérea, sino que localiza a qué altura se produce (central o periférica). El objetivo es acercar esta técnica al personal sanitario y hacer más sencilla su interpretación. (AU)

Oscillometry is a tool that is gradually making its way into the daily routine of pneumology and allergology. It is a simple technique for the patient, which also provides additional information to the classic respiratory function tests. It not only indicates if there is an alteration in the airway, but also locates where it occurs (central or peripheral). The aim is to bring this technique closer to healthcare professionals and facilitate its interpretation. (AU)

Current Trends of Bacterial and Fungal Optoproteins for Novel Optical Applications.

Photoproteins, luminescent proteins or optoproteins are a kind of light-response protein responsible for the conversion of light into biochemical energy that is used by some bacteria or fungi to regulate specific biological processes. Within these specific proteins, there are groups such as the photoreceptors that respond to a given light wavelength and generate reactions susceptible to being used for the development of high-novel applications, such as the optocontrol of metabolic pathways. Photoswitchable proteins play important roles during the development of new materials due to their capacity to change their conformational structure by providing/eliminating a specific light stimulus. Additionally, there are bioluminescent proteins that produce light during a heatless chemical reaction and are useful to be employed as biomarkers in several fields such as imaging, cell biology, disease tracking and pollutant detection. The classification of these optoproteins from bacteria and fungi as photoreceptors or photoresponse elements according to the excitation-emission spectrum (UV-Vis-IR), as well as their potential use in novel applications, is addressed in this article by providing a structured scheme for this broad area of knowledge.

Quantitative Analysis of Clot Deposition on Extracorporeal Life Support Membrane Oxygenators Using Digital and Scanning Electron Microscopy Imaging Techniques.

Device-induced thrombosis remains a major complication of extracorporeal life support (ECLS). To more thoroughly understand how blood components interact with the artificial surfaces of ECLS circuit components, assessment of clot deposition on these surfaces following clinical use is urgently needed. Scanning electron microscopy (SEM), which produces high-resolution images at nanoscale level, allows visualization and characterization of thrombotic deposits on ECLS circuitry. However, methodologies to increase the quantifiability of SEM analysis of ECLS circuit components have yet to be applied clinically. To address these issues, we developed a protocol to quantify clot deposition on ECLS membrane oxygenator gas transfer fiber sheets through digital and SEM imaging techniques. In this study, ECLS membrane oxygenator fiber sheets were obtained, fixed, and imaged after use. Following a standardized process, the percentage of clot deposition on both digital images and SEM images was quantified using ImageJ through blind reviews. The interrater reliability of quantitative analysis among reviewers was evaluated. Although this protocol focused on the analysis of ECLS membrane oxygenators, it is also adaptable to other components of the ECLS circuits such as catheters and tubing. Key features • Quantitative analysis of clot deposition using digital and scanning electron microscopy (SEM) techniques • High-resolution images at nanoscale level • Extracorporeal life support (ECLS) devices • Membrane oxygenators • Blood-contacting surfaces Graphical overview.

Application of the Team Emergency Assessment Measure Scale in undergraduate medical students and interprofessional clinical teams: validity evidence of a Spanish version applied in Chile.

Background: Teamwork is one of the competencies necessary for physicians to work effectively in health systems and is a competency that can be developed with simulation in professionals and medicine students. The Team Emergency Assessment Measurement (TEAM) was created to evaluate the non-technical performance of team members during resuscitation events in real teams. The TEAM scale includes items to assess leadership, teamwork, situational awareness, and task management. An objective evaluation tool in Spanish is valuable for training health professionals at all undergraduate and continuing education levels. This study aimed to generate evidence of the validity of the Team Emergency Assessment Measure (TEAM) in Spanish to measure the performance of medical students and adult, pediatric, and obstetric emergency clinical teams in simulated emergencies as a self-assessment tool. Methods: To develop the Spanish version of the instrument, a forward and backward translation process was followed by independent translators, native and fluent in English and Spanish, and a review by a panel of Chilean experts comprising three trained simulation instructors to verify semantics and cultural equivalence. High-fidelity simulations with debriefing were conducted with 5th-year medical students, in which students and instructors applied the Spanish version of the TEAM scale. In the second stage, adult, pediatric, and obstetric emergency management simulations were conducted using the TEAM scale for real clinical teams as a self-assessment tool. Findings: By applying the overall TEAM scale to medicine students and clinical teams, Cronbach's alpha was 0.921. For medical students' self-assessment, we obtained Cronbach's alpha of 0.869. No significant differences were found between the overall scores and the scores by dimensions evaluated by instructors and students (p > 0.05). In the case of clinical team training, Cronbach's alpha was 0.755 for adult emergency teams, 0.797 for pediatric emergency teams, and 0.853 for obstetric emergency teams. Conclusion: The validated instrument is adequate for evaluating teamwork in medical student simulations by instructors and peers and for self-assessment in adult, pediatric, and obstetric emergency clinical teams.

Enhanced mitochondrial biogenesis promotes neuroprotection in human pluripotent stem cell derived retinal ganglion cells.

Mitochondrial dysfunctions are widely afflicted in central nervous system (CNS) disorders with minimal understanding on how to improve mitochondrial homeostasis to promote neuroprotection. Here we have used human stem cell differentiated retinal ganglion cells (hRGCs) of the CNS, which are highly sensitive towards mitochondrial dysfunctions due to their unique structure and function, to identify mechanisms for improving mitochondrial quality control (MQC). We show that hRGCs are efficient in maintaining mitochondrial homeostasis through rapid degradation and biogenesis of mitochondria under acute damage. Using a glaucomatous Optineurin mutant (E50K) stem cell line, we show that at basal level mutant hRGCs possess less mitochondrial mass and suffer mitochondrial swelling due to excess ATP production load. Activation of mitochondrial biogenesis through pharmacological inhibition of the Tank binding kinase 1 (TBK1) restores energy homeostasis, mitigates mitochondrial swelling with neuroprotection against acute mitochondrial damage for glaucomatous E50K hRGCs, revealing a novel neuroprotection mechanism.

Potential of Salvinia biloba Raddi for removing atrazine and carbendazim from aquatic environments.

In this exploratory study, naturally occurring Salvinia biloba Raddi specimens were assessed for atrazine and carbendazim polluted water remediation. Experiments were carried out over 21 days in glass vessels containing deionized water artificially contaminated with 0, 5, 10, and 20 mg L-1 of atrazine or carbendazim. Atrazine had a pronounced detrimental impact on S. biloba, as no biomass development was observed in all macrophytes exposed to this herbicide in the entire concentration range. However, carbendazim-treated plants were able to grow and survive in the polluted medium even when subjected to the highest concentration of this fungicide (i.e., 20 mg L-1). In addition, increased chlorosis and necrosis were also detected in plants subjected to carbendazim as a result of the high phytotoxicity caused by atrazine. A maximal removal efficiency of ~ 30% was observed for both pesticides at 5 mg L-1 and decreased with increasing concentrations of the pollutants. The spectrum of the FTIR-ATR analysis revealed the existence of various functional groups (e.g., amide, carboxyl, hydroxyl, phosphate, sulfate) on the plants, which could be related to pesticide biosorption. In addition, at the end of the 21-day assay, seven carbendazim-resistant bacteria could be isolated from the roots of fungicide-treated plants. Therefore, the use of autochthonous free-floating S. biloba macrophytes for phytoremediation of aquatic environments contaminated with carbendazim shows great promise. Still, additional research is required to further elucidate the plant-mediated carbendazim elimination process and the role of the herbicide-resistant bacteria, and seek alternative species capable of mitigating atrazine contamination.

Performance evaluation of Moringa oleifera seeds aqueous extract for removing Microcystis aeruginosa and microcystins from municipal treated-water.

Introduction: Toxic microcystins (MCs) produced by cyanoprokaryotes -particularly by the cosmopolitan cyanobacterium Microcystis aeruginosa- pose adverse effects on aquatic organisms and their ecosystem and may also cause serious impacts on human health. These harmful monocyclic heptapeptides are the most prevalent cyanotoxins reported in freshwaters and must be eliminated for avoiding MCs release in receiving water bodies. Hence, this work aimed to test the efficacy of Moringa oleifera seeds water-based extract (MO) as a natural coagulant for removing cyanobacteria (especially M. aeruginosa), microalgae, and its associated MCs from pre-treated municipal wastewaters. Methodology: Four different MO coagulant doses (25, 50, 75 and 100 mg L-1) were investigated for cyanobacteria and microalgae removal by conventional coagulation assays and morphology-based taxonomy studies. Additionally, water turbidity and chlorophyll a (Chl a) content were also determined. Further, the presence and concentration of MCs soluble in water, remaining in the particulate fraction, and flocculated within the residual sludge were assessed using high-performance liquid chromatography coupled with diode array detection (HPLC-DAD). Results: The treatment with MO at 100 mg L-1 substantially reduced the number of cyanobacterial and microalgal species in the treated samples (average removal rate of 93.8% and 86.9%, respectively). These results agreed with a ∼44% concomitant reduction in Chl a and ∼97% reduction in water turbidity (a surrogate marker for suspended solids content). Notably, MCs concentrations in the treated water were significantly lowered to 0.6 ± 0.1 µg L-1 after addition of 100 mg L-1 MO. This value is below the WHO recommended limits for MCs presence in drinking water (<1.0 µg L-1). Discussion: The present study provides promising insights into the applicability of MO as a cost-effective, reliable, and sustainable natural coagulant, particularly for using in developing countries, to eliminate harmful cyanobacteria and cyanotoxins in municipal water treatment facilities.

Tratamiento endovascular con técnica de chimenea para patologías del arco aórtico / Endovascular management with chimney technique for pathologies ofthe aortic arch

Introducción. La patología del arco aórtico se ha tratado principalmente con cirugía por vía abierta, pero con una alta morbimortalidad. Las técnicas endovasculares híbridas y las reconstrucciones en "chimenea" son una técnica válida y segura para disminuir el riesgo y la mortalidad. Métodos. Se presentan dos pacientes con patología del arco aórtico y contraindicación de manejo quirúrgico abierto, atendidos en el Servicio de Cirugía Vascular, Hospital Universitario Clínica de San Rafael, Bogotá, D.C., Colombia. Resultados. Se realizaron dos procedimientos endovasculares del arco aórtico para tratar un aneurisma torácico roto y una úlcera aórtica sintomática, con cubrimiento de los troncos supra aórticos con una endoprótesis y canalización de los vasos supra aórticos con prótesis cubiertas y uso de la "técnica de chimenea", de manera exitosa. Discusión. La patología del arco aórtico es de alta complejidad y se asocia con una morbimortalidad elevada por lo que, en los últimos 20 años se han desarrollado diferentes técnicas utilizando procedimientos percutáneos. Conclusión. La "técnica de chimenea" se puede realizar de una manera mínimamente invasiva en pacientes con patología del arco aórtico, no candidatos para cirugía abierta, con resultados exitosos.

Introduction. Aortic arch pathology has been treated mainly by open surgery, but with high morbidity and mortality. Hybrid endovascular techniques and "chimney" reconstructions are a valid and safe techniques to reduce risk and mortality. Method. Two patients with pathology of the aortic arch and contraindication for open surgical management, treated at the Vascular Surgery Service, Hospital Universitario Clínica de San Rafael, Bogotá, Colombia, are presented. Results. Two endovascular aortic procedures were performed successfully to treat a ruptured thoracic aneurysm and a symptomatic aortic ulcer, with coverage of the supra-aortic trunks with an endoprosthesis and cannulation of the supra-aortic vessels with covered prostheses and use of the "chimney technique". Discussion. The pathology of the aortic arch is highly complex and is associated with high morbidity and mortality, being the reason that during the last 20 years, different techniques have been developed using percutaneous procedures. Conclusions. The "chimney technique" can be performed with successful results in a minimally invasive manner in patients with pathology of the aortic arch, who are not candidates for open surgery

Sono-Enzymatically Embedded Antibacterial Silver-Lignin Nanoparticles on Cork Filter Material for Water Disinfection.

Providing clean drinking water is a great challenge worldwide, especially for low-income countries where the access to safe water is limited. During the last decade, new biotechnological approaches have been explored to improve water management. Among them, the use of antimicrobial nanoparticles for designing innovative centralized and decentralized (point-of-use) water treatment systems for microbial decontamination has received considerable attention. Herein, antimicrobial lignin capped silver nanoparticles (AgLNP) were embedded on residual cork pieces using high-intensity ultrasound coupled with laccase-mediated grafting to obtain biofunctionalized nanomaterial. The developed AgLNP-coated cork proved to be highly efficient to drastically reduce the number of viable Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus in liquid medium. Additionally, the coated-cork was characterized using FTIR-ATR spectroscopy and SEM imaging, and further used as a filter bed in a point-of-use device for water disinfection. The constructed water filtering system significantly reduced the amount of viable E. coli and resistant Bacillus cereus spores from filtered water operating at increasing residence times of 1, 4, 6, 16, 24, and 48 h. Therefore, the presented results prove that the obtained cork-based antimicrobial nanocomposite material could be used as a filtering medium for the development of water filtration system to control pathogen dissemination.

The GPI-Anchored Protein Thy-1/CD90 Promotes Wound Healing upon Injury to the Skin by Enhancing Skin Perfusion.

Wound healing is a highly regulated multi-step process that involves a plethora of signals. Blood perfusion is crucial in wound healing and abnormalities in the formation of new blood vessels define the outcome of the wound healing process. Thy-1 has been implicated in angiogenesis and silencing of the Thy-1 gene retards the wound healing process. However, the role of Thy-1 in blood perfusion during wound closure remains unclear. We proposed that Thy-1 regulates vascular perfusion, affecting the healing rate in mouse skin. We analyzed the time of recovery, blood perfusion using Laser Speckle Contrast Imaging, and tissue morphology from images acquired with a Nanozoomer tissue scanner. The latter was assessed in a tissue sample taken with a biopsy punch on several days during the wound healing process. Results obtained with the Thy-1 knockout (Thy-1-/-) mice were compared with control mice. Thy-1-/- mice showed at day seven, a delayed re-epithelialization, increased micro- to macro-circulation ratio, and lower blood perfusion in the wound area. In addition, skin morphology displayed a flatter epidermis, fewer ridges, and almost no stratum granulosum or corneum, while the dermis was thicker, showing more fibroblasts and fewer lymphocytes. Our results suggest a critical role for Thy-1 in wound healing, particularly in vascular dynamics.

Early-stage response in anaerobic bioreactors due to high sulfate loads: Hydrogen sulfide yield and other organic volatile sulfur compounds as a sign of microbial community modifications.

In this work, the early-stage response of six lab-scale biogas bioreactors fed with different amounts of a sulfate-rich organic agro-industrial effluent was investigated. Biogas characterization, gas chromatography selective for sulfur compounds and high-throughput sequencing of 16S rRNA gene were performed. Hydrogen sulfide (H2S) yield went from transient to steady state in âˆ¼ 2 weeks for all the studied conditions. In addition, volatile sulfur compounds (VSCs), like methanethiol (MeSH) and dimethyl sulfide (DMS), were generated at high sulfate loads. Changes were evidenced in the microbial community structures, with a higher abundance of genes involved in the dissimilatory sulfate-reduction pathway in high loaded sulfate bioreactors, as determined by PICRUSt analysis. Principal component analysis (PCA) and correlation analyses evidenced strong relationships between H2S, VSCs and the microbial community. Sulfate-reducing bacteria (SRB) like Desulfocarbo, Desulfocella and Desulfobacteraceae might be possibly linked with methylation processes of H2S.

Thy-1 (CD90), Integrins and Syndecan 4 are Key Regulators of Skin Wound Healing.

Acute skin wound healing is a multistage process consisting of a plethora of tightly regulated signaling events in specialized cells. The Thy-1 (CD90) glycoprotein interacts with integrins and the heparan sulfate proteoglycan syndecan 4, generating a trimolecular complex that triggers bi-directional signaling to regulate diverse aspects of the wound healing process. These proteins can act either as ligands or receptors, and they are critical for the successful progression of wound healing. The expression of Thy-1, integrins, and syndecan 4 is controlled during the healing process, and the lack of expression of any of these proteins results in delayed wound healing. Here, we review and discuss the roles and regulatory events along the stages of wound healing that support the relevance of Thy-1, integrins, and syndecan 4 as crucial regulators of skin wound healing.

Does timing matter on tocilizumab administration? Clinical, analytical and radiological outcomes in COVID-19.

INTRODUCTION: While there are no pharmacological treatments with proven efficacy for coronavirus disease 2019 (COVID-19), tocilizumab has emerged as a candidate therapy. Some aspects of this therapy are still unknown, including the optimal timing of administration. OBJECTIVE: This observational study aimed to compare the 90-day mortality in two cohorts of patients when the drug was administered within the first 10 days from onset of symptoms or after day 11. METHODS: Patients hospitalised with severe COVID-19 pneumonia who had received tocilizumab were divided into two groups according to when the medication was administered. The primary outcome was 90-day mortality. Secondary outcomes were 30-day mortality, clinical improvement on a 6-item scale by day 6, biomarker improvement by day 6, radiological image improvement by day 10 and SaO2 quotient by day 6. The results in the two groups were compared. Additionally, adverse events relating to tocilizumab were recorded. RESULTS: A total of 112 patients were analysed. Both groups were epidemiologically comparable. The results obtained in the primary efficacy variable of the study (90-day mortality) showed a statistically significant difference in the subgroups according to the time of administration of tocilizumab (18.6% vs 5.0%, p=0.048). There was clinical improvement in 24.1% of patients at 6 days, with similar behaviour in both subgroups. No statistically significant differences were found in the percentage of patients who achieved radiological improvement at 10 days or in the other inflammatory parameters, with the exception of significant reductions in lactate dehydrogenase and C-reactive protein. Administration of tocilizumab was not associated with relevant adverse events. CONCLUSION: To our knowledge, this is the first report of data regarding the timing of administration of tocilizumab in patients with COVID-19 pneumonia. A strategy involving tocilizumab administration after 10 days from onset of symptoms may decrease mortality. Further randomised controlled trials are needed to confirm this emerging hypothesis.

Evaluation of Cadmium Bioaccumulation-Related Physiological Effects in Salvinia biloba: An Insight towards Its Use as Pollutant Bioindicator in Water Reservoirs.

Free-living macrophytes play an important role in the health of aquatic ecosystems. Therefore, the use of aquatic plants as metal biomonitors may be a suitable tool for the management of freshwater reservoirs. Hence, in this study, we assessed the effects of cadmium (Cd) in Salvinia biloba specimens collected from the Middle Paraná River during a 10-day experiment employing artificially contaminated water (100 µM Cd). S. biloba demonstrated a great ability for Cd bioaccumulation in both the root-like modified fronds (named "roots") and the aerial leaf-like fronds (named "leaves") of the plants. Additionally, Cd toxicity was determined by the quantification of photosynthetic pigments (chlorophylls a and b, and carotenoids), flavonoids, and soluble carbohydrate contents in S. biloba over time (1, 3, 5, 7, and 10 days). In general, deterioration was more pronounced in leaves than in roots, suggesting a greater implication of the former in long-term Cd sequestration in S. biloba. Deleterious effects in the appraised parameters were well correlated with the total amount of Cd accumulated in the leaves, and with the qualitative changes observed in the plants' phenotype during the 10-day metal exposure assay. The flavonoids and carotenoids in leaves were highly affected by low Cd levels followed by root carbohydrates. In contrast, chlorophylls and root flavonoids were the least impacted physiological parameters. Therefore, our results demonstrate that S. biloba displays dissimilar organ-linked physiological responses to counteract Cd phytotoxicity and that these responses are also time-dependent. Though further research is needed, our work suggests that easy-handled physiological data obtained from autochthonous free-floating S. biloba specimens may be used as a valuable tool for metal-polluted water biomonitoring.

An Outside-In Switch in Integrin Signaling Caused by Chemical and Mechanical Signals in Reactive Astrocytes.

Astrocyte reactivity is associated with poor repair capacity after injury to the brain, where chemical and physical changes occur in the damaged zone. Astrocyte surface proteins, such as integrins, are upregulated, and the release of pro-inflammatory molecules and extracellular matrix (ECM) proteins upon damage generate a stiffer matrix. Integrins play an important role in triggering a reactive phenotype in astrocytes, and we have reported that α V ß3 Integrin binds to the Thy-1 (CD90) neuronal glycoprotein, increasing astrocyte contractility and motility. Alternatively, α V ß3 Integrin senses mechanical forces generated by the increased ECM stiffness. Until now, the association between the α V ß3 Integrin mechanoreceptor response in astrocytes and changes in their reactive phenotype is unclear. To study the response to combined chemical and mechanical stress, astrocytes were stimulated with Thy-1-Protein A-coated magnetic beads and exposed to a magnetic field to generate mechanical tension. We evaluated the effect of such stimulation on cell adhesion and contraction. We also assessed traction forces and their effect on cell morphology, and integrin surface expression. Mechanical stress accelerated the response of astrocytes to Thy-1 engagement of integrin receptors, resulting in cell adhesion and contraction. Astrocyte contraction then exerted traction forces onto the ECM, inducing faster cell contractility and higher traction forces than Thy-1 alone. Therefore, cell-extrinsic chemical and mechanical signals regulate in an outside-in manner, astrocyte reactivity by inducing integrin upregulation, ligation, and signaling events that promote cell contraction. These changes in turn generate cell-intrinsic signals that increase traction forces exerted onto the ECM (inside-out). This study reveals α V ß3 Integrin mechanoreceptor as a novel target to regulate the harmful effects of reactive astrocytes in neuronal healing.

Effect of intermittent induced aeration on nitrogen removal and denitrifying-bacterial community structure in Cork and gravel vertical flow pilot-scale treatment wetlands.

In this work, we have evaluated the impact of intermittent induced aeration in total nitrogen (TN), ammonia (NH4-N) and nitrate-nitrogen (NO3-N) removal in four pilot-scale vertical flow constructed wetlands (VFCW) (two aerated two non-aerated) using cork by-product or gravel as the filter material and planted with Phragmites australis. Both aerated and non-aerated systems achieved high COD and BOD5 elimination rates (≥ 90%) at the end of the 5-month test period. However, the aerated systems presented maximal COD and BOD5 removal from the third month of operation onwards since air supply favored the oxidative bioprocesses occurring within the wetlands. Cork and gravel aerated VFCW also proved to be more efficient (p < 0.05) in NO3-N removal than the non-aerated systems and this upgraded performance was correlated with a significant higher relative abundance of the nirS gene. The aerated systems also showed a slightly improved NH4-N removal. Noticeably, cork VFCW showed higher TN removal mean values (∼35%) than gravel wetlands (27-28%) regardless aeration. Moreover, cork VFCW showed higher relative abundance of the nosZ gene. Our results demonstrated a better nitrogen elimination for the aerated cork pilot-scale VFCW, and this behavior was correlated with a higher abundance of both nirS and nosZ, two of the key functional genes involved in nitrogen metabolism.

New morphological features based on the Sholl analysis for automatic classification of traced neurons.

BACKGROUND: This article addresses the automatic classification of reconstructed neurons through their morphological features. The purpose was to extend the capabilities of the L-Measure software. METHODS: New morphological features were developed, based on modifications of the conventional Sholl analysis. The lengths of the compartments, as well as their volumes, were added to the features used in the classical analysis in order to improve the results during automatic neuron classification. FSM were used to obtain subsets of lower cardinality from the full feature sets and the usefulness of these subsets was tested through their use in supervised classification tasks. The study was based on two types of neurons belonging to mice: pyramidal and GABAergic interneurons. Furthermore, a set of pyramidal neurons belonging to Later 4 and Layer 5 was analyzed. RESULTS: RF classifier shown the best performance combined with a Wrapper method.U-WNAD set allowed to obtain higher values than WN, A and D in all cases and better results than LM for the filters and wrappers FSM. U-LM-WNAD set, led to the highest AUC values for all the FSM studied. Similar results for different regions of cortex were obtained. Comparison with Existing Methods The new features exhibited high discriminatory power with which the values of AUC and Acc obtained in the experiments exceeded those obtained using only the features provided by L-Measure. CONCLUSIONS: The highest values of AUC and Acc were obtained from the sets U-WNAD and U-LM-WNAD, evidencing the discriminatory power of the new proposed features.

Thy-1 (CD90)-Induced Metastatic Cancer Cell Migration and Invasion Are ß3 Integrin-Dependent and Involve a Ca2+/P2X7 Receptor Signaling Axis.

Cancer cell adhesion to the vascular endothelium is an important step in tumor metastasis. Thy-1 (CD90), a cell adhesion molecule expressed in activated endothelial cells, has been implicated in melanoma metastasis by binding to integrins present in cancer cells. However, the signaling pathway(s) triggered by this Thy-1-Integrin interaction in cancer cells remains to be defined. Our previously reported data indicate that Ca2+-dependent hemichannel opening, as well as the P2X7 receptor, are key players in Thy-1-αVß3 Integrin-induced migration of reactive astrocytes. Thus, we investigated whether this signaling pathway is activated in MDA-MB-231 breast cancer cells and in B16F10 melanoma cells when stimulated with Thy-1. In both cancer cell types, Thy-1 induced a rapid increase in intracellular Ca2+, ATP release, as well as cell migration and invasion. Connexin and Pannexin inhibitors decreased cell migration, implicating a requirement for hemichannel opening in Thy-1-induced cell migration. In addition, cell migration and invasion were precluded when the P2X7 receptor was pharmacologically blocked. Moreover, the ability of breast cancer and melanoma cells to transmigrate through an activated endothelial monolayer was significantly decreased when the ß3 Integrin was silenced in these cancer cells. Importantly, melanoma cells with silenced ß3 Integrin were unable to metastasize to the lung in a preclinical mouse model. Thus, our results suggest that the Ca2+/hemichannel/ATP/P2X7 receptor-signaling axis triggered by the Thy-1-αVß3 Integrin interaction is important for cancer cell migration, invasion and transvasation. These findings open up the possibility of therapeutically targeting the Thy-1-Integrin signaling pathway to prevent metastasis.