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Recent developments in cancer immunotherapy have highlighted the potential of harnessing natural killer (NK) cells in the treatment of neoplastic malignancies. Of these, bispecific antibodies, and NK cell engager (NKCE) protein therapeutics in particular, have been of interest. Here, we used phage display and yeast surface display to engineer RLN131, a unique cross-reactive antibody that binds to human, mouse, and cynomolgus NKp46, an activating receptor found on NK cells. RLN131 induced proliferation and activation of primary NK cells, and was used to create bispecific NCKE constructs of varying configurations and valency. All NCKEs were able to promote greater NK cell cytotoxicity against tumor cells than an unmodified anti-CD20 monoclonal antibody, and activity was observed irrespective of whether the constructs contained a functional Fc domain. Competition binding and fine epitope mapping studies were used to demonstrate that RLN131 binds to a conserved epitope on NKp46, underlying its species cross-reactivity.
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Platelet factor (F)XIII-A is a major cytoplasmic protein (~3% of total) representing ~50% of total circulating FXIII. However, mobilization of FXIII-A during platelet activation is not well defined. To determine mechanisms mediating the retention versus release of platelet FXIII-A, platelets from healthy humans and mice (F13a1-/-, Fga-/-, Plg-/-, Stim1fl/fl, Pf4-Cre and respective controls) were stimulated with thrombin, convulxin+thrombin, or calcium ionophore (A23187), in the absence or presence of inhibitors of transglutaminase activity, mRNA translation, microtubule rearrangement, calpain, and Rho GTPase. Platelet releasates and pellets were separated by (ultra)centrifugation. FXIII-A was detected by immunoblotting and immunofluorescence microscopy. Even following strong dual agonist (convulxin+thrombin) stimulation of human platelets, >80% platelet FXIII-A remained associated with the platelet pellet. In contrast, essentially all tissue factor pathway inhibitor, another cytoplasmic protein in platelets, was released to the supernatant. Pellet-associated FXIII-A was not due to de novo synthesis via platelet F13A1 mRNA. The proportion of platelet FXIII-A retained by, versus released from, activated platelets was partly dependent on STIM1 signaling, microtubule rearrangement, calpain, and RhoA activation, but did not depend on the presence of fibrinogen or plasminogen. Immunofluorescence microscopy confirmed the presence of considerable FXIII-A within the activated platelets. Whereas released FXIII-A was cleaved to FXIII-A* and could be degraded by plasmin, platelet-associated FXIII-A remained uncleaved. Retention of substantial platelet-derived FXIII-A by activated platelets, and its reduced susceptibility to thrombin- and plasmin-mediated proteolysis, suggests platelet FXIII-A is a protected pool with biological role(s) that differs from plasma FXIII.
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OBJECTIVE: To report the efficacy, safety, and feasibility of radiofrequency ablation (RFA) for T1 papillary thyroid carcinoma (PTC) in a large referral center in the United States. PATIENTS AND METHODS: We conducted a retrospective study of 8 patients who underwent RFA for T1 PTC at Mayo Clinic in Rochester Minnesota, between July 1, 2020, and February 28, 2023. The RFA technique and the type of anesthesia are described. Thyroid function, changes in ablated zone, and adverse events were analyzed for up to 24 months after the procedure. RESULTS: Of the 8 patients included in the study, 7 were female and 1 was male with a mean ± SD age of 53±16.4 years. Thyroid status was unaffected in 7 of the 8 patients. The median duration of RFA was 6 minutes (range, 2 to 14.5 minutes) with energy delivered at between 25 and 45 W. The mean ± SD volume of small PTCs was 0.3±0.2 mL, and the mean largest diameter was 9.5±3.3 mm (range, 6 to 15 mm). The mean ± SD ablated volume at 3 to 6 months was larger than the target lesion (0.8±0.7 mL), with a reduction in mean ± SD ablated volume of 0.4±0.4 mL at 7 to 12 months and 0.1±0.06 mL at 13 to 18 months. The ablated zone almost disappeared at 19 to 24 months (0.04±0.04 mL). There were no major adverse events during or after the RFA procedure. CONCLUSION: This is the first reported series of T1 PTC treated with RFA in the United States. Early postablation imaging revealed that the ablated region was larger than the target lesions, followed by a serial decrease in size. Therefore, RFA at centers with such expertise appears to be a safe and effective treatment for small PTCs. Further studies are needed to evaluate its long-term efficacy and the risk of recurrence.
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Urokinase-type plasminogen activator receptor (uPAR) is overexpressed on tumor cells in multiple types of cancer and contributes to disease progression and metastasis. In this work, we engineered a novel bi-paratopic uPAR targeting agent by fusing the binding domains of two native uPAR ligands: uPA and vitronectin, with a flexible peptide linker. The linker length was optimized to facilitate simultaneous engagement of both domains to their adjacent epitopes on uPAR, resulting in a high affinity and avid binding interaction. Furthermore, the individual domains were affinity-matured using yeast surface display and directed evolution, resulting in a bi-paratopic protein with affinity in the picomolar to femtomolar range. This engineered uPAR targeting agent demonstrated significantly enhanced tumor localization in mouse tumor models compared to the native uPAR ligand and warrants further investigation as a diagnostic and therapeutic agent for cancer.
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BACKGROUND: Worldwide, the culturally and linguistically diverse (CALD) population is increasing, and is predicted to reach 405 million by 2050. The delivery of emergency care for the CALD population can be complex due to cultural, social, and language factors. The extent to which cultural, social, and contextual factors influence care delivery to patients from CALD backgrounds throughout their emergency care journey is unclear. Using a systematic approach, this review aims to map the existing evidence regarding emergency healthcare delivery for patients from CALD backgrounds and uses a social ecological framework to provide a broader perspective on cultural, social, and contextual influence on emergency care delivery. METHODS: The Joanna Briggs Institute (JBI) scoping review methodology will be used to guide this review. The population is patients from CALD backgrounds who received care and emergency care clinicians who provided direct care. The concept is healthcare delivery to patients from CALD backgrounds. The context is emergency care. This review will include quantitative, qualitative, and mixed-methods studies published in English from January 1, 2012, onwards. Searches will be conducted in the databases of CINAHL (EBSCO), MEDLINE (Ovid), Embase (Elsevier), SocINDEX (EBSCO), Scopus (Elsevier), and a web search of Google Scholar. A PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) flow diagram will be used to present the search decision process. All included articles will be appraised using the Mixed Methods Appraisal Tool (MMAT). Data will be presented in tabular form and accompanied by a narrative synthesis of the literature. DISCUSSION: Despite the increased use of emergency care service by patients from CALD backgrounds, there has been no comprehensive review of healthcare delivery to patients from CALD backgrounds in the emergency care context (ED and prehospital settings) that includes consideration of cultural, social, and contextual influences. The results of this scoping review may be used to inform future research and strategies that aim to enhance care delivery and experiences for people from CALD backgrounds who require emergency care. SYSTEMATIC REVIEW REGISTRATION: This scoping review has been registered in the Open Science Framework https://doi.org/10.17605/OSF.IO/HTMKQ.
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Diversidade Cultural , Atenção à Saúde , Serviços Médicos de Emergência , Humanos , Idioma , Revisões Sistemáticas como AssuntoRESUMO
Nanoparticle-based systems are extensively investigated for drug delivery. Among others, with superior biocompatibility and enhanced targeting capacity, albumin appears to be a promising carrier for drug delivery. Albumin nanoparticles are highly favored in many disease therapies, as they have the proper chemical groups for modification, cell-binding sites for cell adhesion, and affinity to protein drugs for nanocomplex generation. Herein, this review summarizes the recent fabrication techniques, modification strategies, and application of albumin nanoparticles. We first discuss various albumin nanoparticle fabrication methods, from both pros and cons. Then, we provide a comprehensive introduction to the modification section, including organic albumin nanoparticles, metal albumin nanoparticles, inorganic albumin nanoparticles, and albumin nanoparticle-based hybrids. We finally bring further perspectives on albumin nanoparticles used for various critical diseases.
Albumin appears to be a promising carrier for drug delivery with superior biocompatibility and enhanced targeting capacity. This review focuses on the importance of albumin nanoparticles in drug delivery and concludes the recent fabrication techniques to prepare albumin nanoparticles, the modification strategies to require functional albumin nanoparticles, and critical applications of albumin nanoparticles in various diseases. The aim of this review is to help readers understand the significant potential of albumin nanoparticles in drug delivery.
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Albuminas , Nanopartículas , Humanos , Albuminas/química , Albuminas/administração & dosagem , Nanopartículas/química , Sistemas de Liberação de Medicamentos/métodos , Animais , Portadores de Fármacos/química , Sistemas de Liberação de Fármacos por Nanopartículas/químicaRESUMO
Head and neck squamous cell carcinomas (HNSCCs) are cancers that arise in the mucosa of the upper aerodigestive tract. The five-year patient survival rate is ~50%. Treatment includes surgery, radiation, and/or chemotherapy and is associated with lasting effects even when successful in irradicating the disease. New molecular targets and therapies must be identified to improve outcomes for HNSCC patients. We recently identified bitter taste receptors (taste family 2 receptors, or T2Rs) as a novel candidate family of receptors that activate apoptosis in HNSCC cells through mitochondrial Ca2+ overload and depolarization. We hypothesized that targeting another component of tumor cell metabolism, namely glycolysis, may increase the efficacy of T2R-directed therapies. GLUT1 (SLC2A1) is a facilitated-diffusion glucose transporter expressed by many cancer cells to fuel their increased rates of glycolysis. GLUT1 is already being investigated as a possible cancer target, but studies in HNSCCs are limited. Examination of immortalized HNSCC cells, patient samples, and The Cancer Genome Atlas revealed high expression of GLUT1 and upregulation in some patient tumor samples. HNSCC cells and tumor tissue express GLUT1 on the plasma membrane and within the cytoplasm (perinuclear, likely co-localized with the Golgi apparatus). We investigated the effects of a recently developed small molecule inhibitor of GLUT1, BAY-876. This compound decreased HNSCC glucose uptake, viability, and metabolism and induced apoptosis. Moreover, BAY-876 had enhanced effects on apoptosis when combined at low concentrations with T2R bitter taste receptor agonists. Notably, BAY-876 also decreased TNFα-induced IL-8 production, indicating an additional mechanism of possible tumor-suppressive effects. Our study demonstrates that targeting GLUT1 via BAY-876 to kill HNSCC cells, particularly in combination with T2R agonists, is a potential novel treatment strategy worth exploring further in future translational studies.
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Introduction: This study aims to answer the question of whether adding mobile cone-beam computed tomography (mCBCT) imaging to shape-sensing robotic-assisted bronchoscopy (ssRAB) translates into a quantifiable improvement in the tool-lesion relationship. Methods: Data from 102 peripheral lung lesions with ≥2 sequential mCBCT orbital spins and from 436 lesions with 0-1 spins were prospectively captured and retrospectively analysed. The primary outcome was the tool-lesion relationship status across the first and the last mCBCT spins. Secondary outcomes included 1) the change in distance between the tip of the sampling tool and the centre of the lesion between the first and the last spins and 2) the per-lesion diagnostic yield. Results: Compared to lesions requiring 0-1 spins, lesions requiring ≥2 spins were smaller and had unfavourable bronchus sign and intra-operative sonographic view. On the first spin, 54 lesions (53%) were designated as non-tool-in-lesion (non-TIL) while 48 lesions (47%) were designated as TIL. Of the 54 initially non-TIL cases, 49 (90%) were converted to TIL status by the last spin. Overall, on the last spin, 96 out of 102 lesions (94%) were defined as TIL and six out of 102 lesions (6%) were defined as non-TIL (p<0.0001). The mean distance between the tool and the centre of the lesion decreased from 10.4 to 6.6â mm between the first and last spins (p<0.0001). The overall diagnostic yield was 77%. Conclusion: Targeting traditionally challenging lung lesions, intra-operative volumetric imaging allowed for the conversion of 90% of non-TIL status to TIL. Guidance with mCBCT resulted in a significant decrease in the distance between the tip of the needle to lesion centre.
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BACKGROUND: Patients with pathogenic variants in RASGRP2 (inherited platelet disorder (IPD)-18) exhibit normal platelet counts but impaired platelet aggregation and αIIbß3 activation. Moderate-to-severe bleeding episodes require patients to be transfused with platelets and/or pro-hemostatic agents. We recently demonstrated that hemostatic efficacy of transfused platelets is limited by dysfunctional endogenous platelets in a mouse model of IPD-18 (Rasgrp2-/- mice), as dysfunctional platelets were recruited to the forming hemostatic plug but did not participate in clot contraction. Thus, higher amounts of transfused platelets were required to outcompete these dysfunctional cells and to reverse bleeding. OBJECTIVE: We here studied the usefulness of thromboelastography with platelet mapping (TEG-PM) for ex vivo monitoring of the hemostatic potential in Rasgrp2-/- mice transfused with various amounts of wild-type (WT) platelets. METHODS: Whole blood (WB) samples from WT and Rasgrp2-/- mice were tested in TEG-PM and parameters for clot formation and contraction (K time, α-angle, maximum amplitude [MA]) were measured. RESULTS: Rasgrp2-/- WB samples did not contract in TEG-PM, consistent with a critical role of this protein in αIIbß3 activation. Addition of WT platelets improved TEG parameters in a ratio-dependent manner, consistent with our recent in vivo studies showing impaired hemostasis at a 5:1, but not at a 2:1 ratio of mutant to WT platelets. K and α values were identified as better predictors of transfusion efficacy than MA, the most platelet-dependent TEG parameter. CONCLUSION: This proof-of-concept study supports the use of TEG-PM to monitor platelet transfusion ratios and hemostatic potential in IPD-18 and potentially other platelet disorders.
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Background: The concept of neurodiversity draws upon scientific research, and lessons from practice and lived experience to suggest new ways of thinking about neurodevelopmental conditions. Among the formative observations are that characteristics associated with neurodevelopmental conditions are part of a "broader phenotype" of variation across the whole population, and that there appear to be "transdiagnostic" similarities as well as differences in these characteristics. These observations raise important questions that have implications for understanding diversity in neurodevelopmental conditions and in neurocognitive phenotypes across the whole population. Method: The present work examines broader phenotypes using seven widely used self-report assessments of traits associated with autism, ADHD, dyslexia, Developmental Coordination Disorder/dyspraxia, tic disorders/Tourette's, cortical hyperexcitability associated with subclinical epilepsy, and sensory sensitivities. A representative sample of 995 adults (aged 17-77) in the UK completed self-report measures of neurodiversity, wellbeing, generalized anxiety, and depression, and cognitive abilities (nonverbal intelligence and executive functioning). Results: We used confirmatory factor analysis to test whether variation and covariation was better characterized (1) by traditional diagnostic labels, or (2) transdiagnostically according to similarities in functions, behaviours, or phenomena. Results indicated that neurodiversity characteristics were best explained using a bifactor model with one general "N" factor and four condition-specific factors. Conclusion: This was the largest examination to date of the factor structure of broader phenotypes relevant to neurodevelopmental conditions. It provides critical benchmark data, and a framework approach for asking systematic questions about the structure of neurocognitive diversities seen in the whole population and in people with one or more diagnoses.
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Importance: Weight loss (WL) during the first month of a behavioral program is associated with longer-term WL. Testing of translatable and adaptive obesity programs is needed. Objective: To compare brief, extended, and no telephone coaching for individuals with suboptimal response (ie, 1-month WL <4%) within an online WL program. Design, Setting, and Participants: This randomized clinical trial with enrollment between March 2019 and April 2022 (data collection completed May 2023) was conducted at an academic research center in the US. Eligible participants included adults aged 18 to 70 years with daily access to internet and a body mass index between 25 and 45. Interventions: All participants received an automated online WL program (4 months) and WL maintenance program (8 months), consisting of video lessons, self-monitoring, and personalized feedback. Participants were randomized, such that individuals with suboptimal response received either brief telephone coaching (3 calls during weeks 5-8), extended telephone coaching (12 calls during weeks 5-16), or no coaching (control). Coaching included education, problem solving, and goal setting, and promoted engagement with the online program. Main Outcomes and Measures: The primary outcomes were percent weight change and proportion of participants achieving 5% or greater WL at 4 and 12 months. A priori hypotheses for WL were that WL for extended coaching would be greater than for brief coaching, and both extended and brief coaching would be greater than no coaching (control). A longitudinal mixed-effects model with participant-specific intercept was used to examine intervention effects on percent WL at 4 and 12 months. Secondary analyses focused on program engagement and cost/kilogram of WL. Results: The study included a total of 437 participants who reported WL at 1 month (mean [SD] age, 50.8 [11.4] years; mean [SD] BMI, 34.6 [5.0]; 305 female [69.8%] and 132 male [30.2%]) with 148 randomized to extended coaching, 143 assigned to brief coaching, and 146 assigned to the control group. Of all participants, 346 (79.2%) were considered to have a suboptimal response. WL at 4 months was significantly greater in the extended coaching group (mean [SD] WL, -7.0% [5.1%]) and brief coaching group (mean [SD] WL, -6.2% [4.7%]) vs the control group (mean [SD] WL, -4.5% [4.7%]) (P < .001). Similarly, the proportion of participants achieving 5% or greater WL at 4 months was greater in the extended coaching group (89 participants [65.9%]) and brief coaching group (77 participants [58.5%]) vs control group (46 participants [36.5%]) (P < .001). At 12 months, a similar pattern was observed for achievement of 5% WL or greater (extended coaching, 63 participants [48.1%]; brief coaching, 58 participants [45.9%]; control, 38 participants [32.8%]; P = .03). Percent WL at 12 months was significantly higher in extended coaching vs control (mean [SD] WL for extended coaching, -5.5% [6.7%]; mean [SD] WL for control, -3.9% [7.4%]; P = .03) but not for brief coaching (mean [SD] WL, -4.9% [6.1%]).Both the brief and extended coaching groups watched more lessons and self-monitored on more days compared with the control group. The cost per additional kilogram of WL, beyond that of the control group, was $50.09 for brief coaching and $92.65 for extended coaching. Conclusions and Relevance: In this randomized clinical trial testing an adaptive intervention, the provision of coaching for individuals with suboptimal response improved WL and was cost-effective; further testing in clinical settings (eg, health care systems) is warranted. Trial Registration: ClinicalTrials.gov Identifier: NCT03867981.
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Tutoria , Obesidade , Telefone , Programas de Redução de Peso , Humanos , Feminino , Masculino , Programas de Redução de Peso/métodos , Pessoa de Meia-Idade , Adulto , Tutoria/métodos , Obesidade/terapia , Redução de Peso , IdosoRESUMO
Contemporary pose estimation methods enable precise measurements of behavior via supervised deep learning with hand-labeled video frames. Although effective in many cases, the supervised approach requires extensive labeling and often produces outputs that are unreliable for downstream analyses. Here, we introduce 'Lightning Pose', an efficient pose estimation package with three algorithmic contributions. First, in addition to training on a few labeled video frames, we use many unlabeled videos and penalize the network whenever its predictions violate motion continuity, multiple-view geometry and posture plausibility (semi-supervised learning). Second, we introduce a network architecture that resolves occlusions by predicting pose on any given frame using surrounding unlabeled frames. Third, we refine the pose predictions post hoc by combining ensembling and Kalman smoothing. Together, these components render pose trajectories more accurate and scientifically usable. We released a cloud application that allows users to label data, train networks and process new videos directly from the browser.
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Algoritmos , Teorema de Bayes , Gravação em Vídeo , Animais , Gravação em Vídeo/métodos , Aprendizado de Máquina Supervisionado , Computação em Nuvem , Software , Postura/fisiologia , Aprendizado Profundo , Processamento de Imagem Assistida por Computador/métodos , Comportamento AnimalRESUMO
Akt is an important kinase in metabolism. Akt also phosphorylates and activates endothelial and neuronal nitric oxide (NO) synthases (eNOS and nNOS, respectively) expressed in M0 (unpolarized) macrophages. We showed that e/nNOS NO production downstream of bitter taste receptors enhances macrophage phagocytosis. In airway epithelial cells, we also showed that the activation of Akt by a small molecule (SC79) enhances NO production and increases levels of nuclear Nrf2, which reduces IL-8 transcription during concomitant stimulation with Toll-like receptor (TLR) 5 agonist flagellin. We hypothesized that SC79's production of NO in macrophages might likewise enhance phagocytosis and reduce the transcription of some pro-inflammatory cytokines. Using live cell imaging of fluorescent biosensors and indicator dyes, we found that SC79 induces Akt activation, NO production, and downstream cGMP production in primary human M0 macrophages. This was accompanied by a reduction in IL-6, IL-8, and IL-12 production during concomitant stimulation with bacterial lipopolysaccharide, an agonist of pattern recognition receptors including TLR4. Pharmacological inhibitors suggested that this effect was dependent on Akt and Nrf2. Together, these data suggest that several macrophage immune pathways are regulated by SC79 via Akt. A small-molecule Akt activator may be useful in some infection settings, warranting future in vivo studies.
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Citocinas , Macrófagos , Óxido Nítrico , Fagocitose , Proteínas Proto-Oncogênicas c-akt , Humanos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fagocitose/efeitos dos fármacos , Macrófagos/metabolismo , Macrófagos/efeitos dos fármacos , Citocinas/metabolismo , Óxido Nítrico/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , GMP Cíclico/metabolismo , Lipopolissacarídeos/farmacologiaRESUMO
Pneumatosis intestinalis (PI) is a rare medical and post-surgical sequela of multiple different etiologies which can be either benign or life-threatening. Various mechanisms have been proposed to explain the occurrence of PI; however, the pathophysiology is dependent on the suspected cause. The condition is largely categorized into two broad groups: idiopathic PI, which remains relatively uncommon, and secondary PI. The latter often surfaces as a result of a wide array of both gastrointestinal and non-gastrointestinal illnesses. These encompass vascular compromise, bowel mucosal disruption, gastrointestinal dysmotility, as well as infectious and immunological etiologies. Management ranges from conservative medical strategies to emergent surgical intervention. We present the first case to our knowledge of spontaneous PI developing within five days of a surgical gastrostomy tube (SGT) placement in a 79-year-old female with glottic squamous cell carcinoma which unfortunately proved fatal. The purpose of this case report is to highlight a rare fatal complication of a common surgical procedure and the necessity of initiating interdisciplinary management quickly to determine the best treatment course.
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OBJECTIVE: Shape-sensing robotic-assisted bronchoscopy is an emerging technology for the sampling of pulmonary lesions. We seek to characterize the shape-sensing robotic-assisted bronchoscopy learning curve at an academic center. METHODS: Shape-sensing robotic-assisted bronchoscopy procedures performed by 9 proceduralists at a single institution were analyzed. Cumulative sum analyses were performed to examine diagnostic sampling and procedure time over each operator's first 50 cases, with the acceptable yield threshold set to 73%. RESULTS: During the study period, 442 patients underwent sampling of 551 lesions. Each operator sampled 61 lesions (interquartile range, 60-63 lesions). Lesion size was 1.90 cm (interquartile range, 1.33-2.80 cm). The median procedure time for single-target cases decreased from 62 minutes during the first 10 cases to 39 minutes after case 40 (P < .001). The overall diagnostic yield was 72% (range, 58%-83%). Six of 9 operators achieved proficiency over the study period. An aggregated cumulative sum analysis of those who achieved competency demonstrated a steep improvement between lesions 1 and 21 and crossing of the competency threshold by lesion 25. Temporal analysis of yield-related lesion characteristics demonstrated that at approximately lesion 20, more challenging lesions were increasingly targeted, as evidenced by smaller target size, higher rates of unfavorable radial endobronchial ultrasound views, and a negative bronchus sign. CONCLUSIONS: Skills acquisition in shape-sensing robotic-assisted bronchoscopy is variable. Approximately half of proceduralists become facile with the technology within 25 lesions. After the initial learning phase, operators increasingly target lesions with more challenging features. Overall, these findings can inform certification and competency standards and provide new users with expectations related to performance over time.
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Interplay between platelets, coagulation factors, endothelial cells (ECs) and fibrinolytic factors is necessary for effective hemostatic plug formation. This study describes a four-dimensional (4D) imaging platform to visualize and quantify hemostatic plug components in mice with high spatiotemporal resolution. Fibrin accumulation following laser-induced vascular injury was observed at the platelet plug-EC interface, controlled by the antagonistic balance between fibrin generation and breakdown. We observed less fibrin accumulation in mice expressing low levels of tissue factor (TFlow) or F12-/- mice compared to controls, whereas increased fibrin accumulation, including on the vasculature adjacent to the platelet plug, was observed in plasminogen-deficient mice or wild-type mice treated with tranexamic acid (TXA). Phosphatidylserine (PS), a membrane lipid critical for the assembly of coagulation factors, was first detected at the platelet plug-EC interface, followed by exposure across the endothelium. Impaired PS exposure resulted in a significant reduction in fibrin accumulation in cyclophilin D-/- mice. Adoptive transfer studies demonstrated a key role for PS exposure on platelets, and to a lesser degree on ECs, in fibrin accumulation during hemostatic plug formation. Together, these studies suggest that (1) platelets are the functionally dominant procoagulant cellular surface, and (2) plasmin is critical for limiting fibrin accumulation at the site of a forming hemostatic plug.
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Neuroinflammation and accumulation of Amyloid Beta (Aß) accompanied by deterioration of special memory are hallmarks of Alzheimer's disease (AD). Effective preventative and treatment options for AD are still needed. Microglia in AD brains are characterized by elevated levels of microRNA-17 (miR-17), which is accompanied by defective autophagy, Aß accumulation, and increased inflammatory cytokine production. However, the effect of targeting miR-17 on AD pathology and memory loss is not clear. To specifically inhibit miR-17 in microglia, we generated mannose-coated lipid nanoparticles (MLNPs) enclosing miR-17 antagomir (Anti-17 MLNPs), which are targeted to mannose receptors readily expressed on microglia. We used a 5XFAD mouse model (AD) that recapitulates many AD-related phenotypes observed in humans. Our results show that Anti-17 MLNPs, delivered to 5XFAD mice by intra-cisterna magna injection, specifically deliver Anti-17 to microglia. Anti-17 MLNPs downregulated miR-17 expression in microglia but not in neurons, astrocytes, and oligodendrocytes. Anti-17 MLNPs attenuated inflammation, improved autophagy, and reduced Aß burdens in the brains. Additionally, Anti-17 MLNPs reduced the deterioration in spatial memory and decreased anxiety-like behavior in 5XFAD mice. Therefore, targeting miR-17 using MLNPs is a viable strategy to prevent several AD pathologies. This selective targeting strategy delivers specific agents to microglia without the adverse off-target effects on other cell types. Additionally, this approach can be used to deliver other molecules to microglia and other immune cells in other organs.
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Doença de Alzheimer , Encéfalo , Modelos Animais de Doenças , Manose , Camundongos Transgênicos , MicroRNAs , Microglia , Nanopartículas , Animais , Doença de Alzheimer/metabolismo , Doença de Alzheimer/tratamento farmacológico , MicroRNAs/metabolismo , Nanopartículas/administração & dosagem , Camundongos , Microglia/metabolismo , Microglia/efeitos dos fármacos , Manose/farmacologia , Encéfalo/metabolismo , Encéfalo/efeitos dos fármacos , Peptídeos beta-Amiloides/metabolismo , Lipídeos , Masculino , Antagomirs/farmacologia , Antagomirs/administração & dosagemRESUMO
Neonates and young infants are known to have limited responses to pediatric vaccines due to reduced germinal center formation. Extended vaccine antigen dosing was previously shown to expand germinal center formation and improve humoral responses in adult mice. We report that sustained antigen delivery through sequential dosing overcomes neonatal limitations to form germinal center reactions and improves humoral immunity. Thus, vaccine strategies that extend the release of vaccine antigens may reduce the number of doses, and time needed, to achieve protective immunity in neonates and young infants.
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BACKGROUND AND OBJECTIVE: Robotic-assisted bronchoscopy (RAB) is an emerging modality to sample pulmonary lesions. Cone-beam computed tomography (CBCT) can be incorporated into RAB. We investigated the magnitude and predictors of patient and staff radiation exposure during mobile CBCT-guided shape-sensing RAB. METHODS: Patient radiation dose was estimated by cumulative dose area product (cDAP) and cumulative reference air kerma (cRAK). Staff equivalent dose was calculated based on isokerma maps and a phantom simulation. Patient, lesion and procedure-related factors associated with higher radiation doses were identified by logistic regression models. RESULTS: A total of 198 RAB cases were included in the analysis. The median patient cDAP and cRAK were 10.86 Gy cm2 (IQR: 4.62-20.84) and 76.20 mGy (IQR: 38.96-148.38), respectively. Among staff members, the bronchoscopist was exposed to the highest median equivalent dose of 1.48 µSv (IQR: 0.85-2.69). Both patient and staff radiation doses increased with the number of CBCT spins and targeted lesions (p < 0.001 for all comparisons). Patient obesity, negative bronchus sign, lesion size <2.0 cm and inadequate sampling by on-site evaluation were associated with a higher patient dose, while patient obesity and inadequate sampling by on-site evaluation were associated with a higher bronchoscopist equivalent dose. CONCLUSION: The magnitude of patient and staff radiation exposure during CBCT-RAB is aligned with safety thresholds recommended by regulatory authorities. Factors associated with a higher radiation exposure during CBCT-RAB can be identified pre-operatively and solicit procedural optimization by reinforcing radiation protective measures. Future studies are needed to confirm these findings across multiple institutions and practices.