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1.
Blood ; 143(26): 2735-2748, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38518105

RESUMO

ABSTRACT: Acute lymphoblastic leukemia (ALL) arises from the uncontrolled proliferation of B-cell precursors (BCP-ALL) or T cells (T-ALL). Current treatment protocols obtain high cure rates in children but are based on toxic polychemotherapy. Novel therapies are urgently needed, especially in relapsed/refractory (R/R) disease, high-risk (HR) leukemias and T-ALL, in which immunotherapy approaches remain scarce. Although the interleukin-7 receptor (IL-7R) plays a pivotal role in ALL development, no IL-7R-targeting immunotherapy has yet reached clinical application in ALL. The IL-7Rα chain (CD127)-targeting IgG4 antibody lusvertikimab (LUSV; formerly OSE-127) is a full antagonist of the IL-7R pathway, showing a good safety profile in healthy volunteers. Here, we show that ∼85% of ALL cases express surface CD127. We demonstrate significant in vivo efficacy of LUSV immunotherapy in a heterogeneous cohort of BCP- and T-ALL patient-derived xenografts (PDX) in minimal residual disease (MRD) and overt leukemia models, including R/R and HR leukemias. Importantly, LUSV was particularly effective when combined with polychemotherapy in a phase 2-like PDX study with CD127high samples leading to MRD-negativity in >50% of mice treated with combination therapy. Mechanistically, LUSV targeted ALL cells via a dual mode of action comprising direct IL-7R antagonistic activity and induction of macrophage-mediated antibody-dependent cellular phagocytosis (ADCP). LUSV-mediated in vitro ADCP levels significantly correlated with CD127 expression levels and the reduction of leukemia burden upon treatment of PDX animals in vivo. Altogether, through its dual mode of action and good safety profile, LUSV may represent a novel immunotherapy option for any CD127+ ALL, particularly in combination with standard-of-care polychemotherapy.


Assuntos
Ensaios Antitumorais Modelo de Xenoenxerto , Animais , Humanos , Camundongos , Receptores de Interleucina-7/antagonistas & inibidores , Camundongos SCID , Fagocitose/efeitos dos fármacos , Subunidade alfa de Receptor de Interleucina-7 , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/imunologia , Feminino , Camundongos Endogâmicos NOD , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais Humanizados/farmacologia , Linhagem Celular Tumoral , Antineoplásicos Imunológicos/farmacologia , Antineoplásicos Imunológicos/uso terapêutico
2.
Nat Immunol ; 14(2): 127-35, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23263556

RESUMO

Interleukin 7 (IL-7) has a critical role in the development of early CD4(-)CD8(-) double-negative (DN) thymocytes. Although the transcription factor STAT5 is an important component of IL-7 signaling, differences in the phenotypes of mice deficient in STAT5, IL-7, IL-7 receptor alpha (IL-7rα) or the kinase Jak3 suggest the existence of STAT5-independent IL-7 signaling. Here we found that IL-7-Jak3 signals activated the transcription factor NFATc1 in DN thymocytes by phosphorylating Tyr371 in the regulatory region of NFATc1. This NFAT-activation pathway was critical for the survival and development of DN thymocytes, as deficiency in NFATc1 blocked thymocyte development at the DN1 stage, leading to T cell lymphopenia. In addition, our results demonstrated a cooperative function for NFATc1 and STAT5 in guiding thymocyte development in response to IL-7 signals.


Assuntos
Interleucina-7/genética , Fatores de Transcrição NFATC/genética , Fator de Transcrição STAT5/genética , Transdução de Sinais/imunologia , Timócitos/citologia , Animais , Antígenos CD4/genética , Antígenos CD4/imunologia , Antígenos CD8/genética , Antígenos CD8/imunologia , Diferenciação Celular , Regulação da Expressão Gênica , Interleucina-7/imunologia , Janus Quinase 3/genética , Janus Quinase 3/imunologia , Linfopenia/imunologia , Linfopenia/patologia , Camundongos , Camundongos Transgênicos , Fatores de Transcrição NFATC/deficiência , Fosforilação , Regiões Promotoras Genéticas , Receptores de Interleucina-7/genética , Receptores de Interleucina-7/imunologia , Fator de Transcrição STAT5/imunologia , Timócitos/imunologia , Transcrição Gênica
3.
Eur J Neurosci ; 57(9): 1546-1560, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36918400

RESUMO

Visual attention is mainly goal directed and allocated based on the upcoming action. However, it is unclear how far this feature of gaze behaviour generalizes in more naturalistic settings. The present study investigates the influence of action affordances on active inference processes revealed by eye movements during interaction with familiar and novel tools. In a between-subject design, a cohort of participants interacted with a virtual reality controller in a low-realism environment; another performed the task with an interaction setup that allowed differentiated hand and finger movements in a high-realism environment. We investigated the differences in odds of fixations and their eccentricity towards the tool parts before action initiation. The results show that participants fixate more on the tool's effector part before action initiation when asked to produce tool-specific movements, especially with unfamiliar tools. These findings suggest that fixations are made in a task-oriented way to plan the distal goals of producing the task- and tool-specific actions well before action initiation. Moreover, with more realistic action affordance, fixations were biased towards the tool handle when it was oriented incongruent with the subjects' handedness. We hypothesize that these fixations are made towards the proximal goal of planning the grasp even though the perceived action on the tools is identical for both experimental setups. Taken together, proximal and distal goal-oriented planning is contextualized to the realism of action/interaction afforded by an environment.


Assuntos
Objetivos , Desempenho Psicomotor , Humanos , Movimentos Oculares , Movimento , Cognição
4.
Eur J Immunol ; 52(6): 895-906, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35365883

RESUMO

CD8+ memory T cells (TM ) are crucial for long-term protection from infections and cancer. Multiple cell types and cytokines are involved in the regulation of CD8+ T cell responses and subsequent TM formation. Besides their direct antiviral effects, type I interferons (IFN-I) modulate CD8+ T cell immunity via their action on several immune cell subsets. However, it is largely unclear how nonimmune cells are involved in this multicellular network modulating CD8+ TM formation. Fibroblastic reticular cells (FRCs) form the 3D scaffold of secondary lymphoid organs, express the IFN-I receptor (IFNAR), and modulate adaptive immune responses. However, it is unclear whether and how early IFNAR signals in lymph node (LN) FRCs affect CD8+ TM differentiation. Using peptide vaccination and viral infection, we studied CD8+ TM differentiation in mice with an FRC-specific IFNAR deletion (FRCΔIFNAR ). We show here that the differentiation of CD8+ TCR-transgenic T cells into central memory cells (TCM ) is enhanced in peptide-vaccinated FRCΔIFNAR mice. Conversely, vesicular stomatitis virus infection of FRCΔIFNAR mice is associated with impaired TCM formation and the accumulation of vesicular stomatitis virus specific double-positive CD127hi KLRG-1hi effector memory T cells. In summary, we provide evidence for a context-dependent contribution of FRC-specific IFNAR signaling to CD8+ TM differentiation.


Assuntos
Vacinas Anticâncer , Estomatite Vesicular , Animais , Linfócitos T CD8-Positivos , Fibroblastos , Camundongos , Camundongos Endogâmicos C57BL , Vacinas de Subunidades Antigênicas , Estomatite Vesicular/metabolismo , Estomatite Vesicular/patologia
5.
Phys Chem Chem Phys ; 25(34): 23069-23080, 2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37605928

RESUMO

Chemical disorder has a major impact on the characterization of the atomic-scale properties of highly complex chemical compounds, such as the properties of point defects. Due to the vast amount of possible atomic configurations, the study of such properties becomes intractable if treated with direct sampling. In this work, we propose an alternative approach, in which samples are selected based on the local atomic composition around the defect, and the defect formation energy is obtained as a function of this local composition with a reduced computational cost. We apply this approach to (U, Pu)O2 nuclear fuels. The formation-energy distribution is computed using machine-learning generative methods, and used to investigate the impact of chemical disorder and the range of influence of local composition on the defect properties. The predicted distributions are then used to calculate the concentration of thermal defects. This approach allows for the first time for the computation of the latter property with a physically meaningful exploration of the configuration space, and opens the way to a more efficient determination of physico-chemical properties in other chemically-disordered compounds such as high-entropy alloys.

6.
J Neuroinflammation ; 19(1): 17, 2022 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-35027063

RESUMO

BACKGROUND: Toxoplasma gondii (T. gondii) is a highly successful parasite being able to cross all biological barriers of the body, finally reaching the central nervous system (CNS). Previous studies have highlighted the critical involvement of the blood-brain barrier (BBB) during T. gondii invasion and development of subsequent neuroinflammation. Still, the potential contribution of the choroid plexus (CP), the main structure forming the blood-cerebrospinal fluid (CSF) barrier (BCSFB) have not been addressed. METHODS: To investigate T. gondii invasion at the onset of neuroinflammation, the CP and brain microvessels (BMV) were isolated and analyzed for parasite burden. Additionally, immuno-stained brain sections and three-dimensional whole mount preparations were evaluated for parasite localization and morphological alterations. Activation of choroidal and brain endothelial cells were characterized by flow cytometry. To evaluate the impact of early immune responses on CP and BMV, expression levels of inflammatory mediators, tight junctions (TJ) and matrix metalloproteinases (MMPs) were quantified. Additionally, FITC-dextran was applied to determine infection-related changes in BCSFB permeability. Finally, the response of primary CP epithelial cells to T. gondii parasites was tested in vitro. RESULTS: Here we revealed that endothelial cells in the CP are initially infected by T. gondii, and become activated prior to BBB endothelial cells indicated by MHCII upregulation. Additionally, CP elicited early local immune response with upregulation of IFN-γ, TNF, IL-6, host-defence factors as well as swift expression of CXCL9 chemokine, when compared to the BMV. Consequently, we uncovered distinct TJ disturbances of claudins, associated with upregulation of MMP-8 and MMP-13 expression in infected CP in vivo, which was confirmed by in vitro infection of primary CP epithelial cells. Notably, we detected early barrier damage and functional loss by increased BCSFB permeability to FITC-dextran in vivo, which was extended over the infection course. CONCLUSIONS: Altogether, our data reveal a close interaction between T. gondii infection at the CP and the impairment of the BCSFB function indicating that infection-related neuroinflammation is initiated in the CP.


Assuntos
Plexo Corióideo , Toxoplasmose Cerebral , Barreira Hematoencefálica/metabolismo , Plexo Corióideo/metabolismo , Células Endoteliais , Humanos , Imunidade , Toxoplasmose Cerebral/metabolismo
7.
Geophys Res Lett ; 49(13): e2021GL097507, 2022 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-36245953

RESUMO

Below hard-bedded glaciers, both basal friction and distributed subglacial drainage are thought to be controlled by a network of cavities. Previous coupled hydro-mechanical models, however, describe cavity-driven friction and hydraulic transmissivity independently, resulting in a physically inconsistent cavity evolution between the two components of the models. Here, we overcome this issue by describing the hydro-mechanical system using a common cavity-evolution description, that governs both transient friction and hydraulic transmissivity. We show that our coupling approach is superior to previous formulations in explaining a unique observation record of glacier sliding speed from the French Alps. We find that, at multi-day to multi-decadal timescales, sliding speed can be expressed as a direct function of basal shear stress and water discharge, without accounting for water pressure, which simply adjusts to maintain the cavitation ratio needed to accommodate the water supply.

8.
Eur J Immunol ; 50(6): 846-857, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32043573

RESUMO

The survival of peripheral T cells is dependent on their access to peripheral LNs (pLNs) and stimulation by IL-7. In pLNs fibroblastic reticular cells (FRCs) and lymphatic endothelial cells (LECs) produce IL-7 suggesting their contribution to the IL-7-dependent survival of T cells. However, IL-7 production is detectable in multiple organs and is not restricted to pLNs. This raises the question whether pLN-derived IL-7 is required for the maintenance of peripheral T cell homeostasis. Here, we show that numbers of naive T cells (TN ) remain unaffected in pLNs and spleen of mice lacking Il7 gene activity in pLN FRCs, LECs, or both. In contrast, frequencies of central memory T cells (TCM ) are reduced in FRC-specific IL-7 KO mice. Thus, steady state IL-7 production by pLN FRCs is critical for the maintenance of TCM , but not TN , indicating that both T cell subsets colonize different ecological niches in vivo.


Assuntos
Sobrevivência Celular , Fibroblastos/imunologia , Memória Imunológica , Interleucina-7/imunologia , Linfonodos/imunologia , Linfócitos T/imunologia , Animais , Fibroblastos/citologia , Interleucina-7/genética , Linfonodos/citologia , Camundongos , Camundongos Knockout , Linfócitos T/citologia
9.
Nucleic Acids Res ; 47(11): 5867-5879, 2019 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-30949712

RESUMO

In the yeast U1 snRNP the Prp39/Prp42 heterodimer is essential for early steps of spliceosome assembly. In metazoans no Prp42 ortholog exists, raising the question how the heterodimer is functionally substituted. Here we present the crystal structure of murine PRPF39, which forms a homodimer. Structure-guided point mutations disrupt dimer formation and inhibit splicing, manifesting the homodimer as functional unit. PRPF39 expression is controlled by NMD-inducing alternative splicing in mice and human, suggesting a role in adapting splicing efficiency to cell type specific requirements. A phylogenetic analysis reveals coevolution of shortened U1 snRNA and the absence of Prp42, which correlates with overall splicing complexity in different fungi. While current models correlate the diversity of spliceosomal proteins with splicing complexity, our study highlights a contrary case. We find that organisms with higher splicing complexity have substituted the Prp39/Prp42 heterodimer with a PRPF39 homodimer.


Assuntos
Proteínas Nucleares/fisiologia , Proteínas de Ligação a RNA/fisiologia , Ribonucleoproteína Nuclear Pequena U1/química , Proteínas de Saccharomyces cerevisiae/química , Processamento Alternativo , Animais , Linfócitos T CD8-Positivos/citologia , Dimerização , Células HEK293 , Humanos , Camundongos , Proteínas Nucleares/química , Proteínas Nucleares/metabolismo , Fases de Leitura Aberta , Filogenia , Mutação Puntual , Precursores de RNA/metabolismo , Splicing de RNA , Fatores de Processamento de RNA/genética , RNA Nuclear Pequeno/metabolismo , Proteínas de Ligação a RNA/química , Ribonucleoproteína Nuclear Pequena U1/metabolismo , Saccharomyces cerevisiae/genética , Spliceossomos/metabolismo
10.
Sensors (Basel) ; 21(9)2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-34062827

RESUMO

The reproduction and simulation of workplaces, and the analysis of body postures during work processes, are parts of ergonomic risk assessments. A commercial virtual reality (VR) system offers the possibility to model complex work scenarios as virtual mock-ups and to evaluate their ergonomic designs by analyzing motion behavior while performing work processes. In this study a VR tracking sensor system (HTC Vive tracker) combined with an inverse kinematic model (Final IK) was compared with a marker-based optical motion capture system (Qualisys). Marker-based optical motion capture systems are considered the gold standard for motion analysis. Therefore, Qualisys was used as the ground truth in this study. The research question to be answered was how accurately the HTC Vive System combined with Final IK can measure joint angles used for ergonomic evaluation. Twenty-six subjects were observed simultaneously with both tracking systems while performing 20 defined movements. Sixteen joint angles were analyzed. Joint angle deviations between ±6∘ and ±42∘ were identified. These high deviations must be considered in ergonomic risk assessments when using a VR system. The results show that commercial low-budget tracking systems have the potential to map joint angles. Nevertheless, substantial weaknesses and inaccuracies in some body regions must be taken into account. Recommendations are provided to improve tracking accuracy and avoid systematic errors.


Assuntos
Realidade Virtual , Ergonomia , Humanos , Movimento (Física) , Medição de Risco , Tecnologia
11.
J Neuroinflammation ; 16(1): 159, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31352901

RESUMO

BACKGROUND: It has become increasingly evident that the immune and nervous systems are closely intertwined, relying on one another during regular homeostatic conditions. Prolonged states of imbalance between neural and immune homeostasis, such as chronic neuroinflammation, are associated with a higher risk for neural damage. Toxoplasma gondii is a highly successful neurotropic parasite causing persistent subclinical neuroinflammation, which is associated with psychiatric and neurodegenerative disorders. Little is known, however, by what means neuroinflammation and the associated neural impairment can be modulated by peripheral inflammatory processes. METHODS: Expression of immune and synapse-associated genes was assessed via quantitative real-time PCR to investigate how T. gondii infection-induced chronic neuroinflammation and associated neuronal alterations can be reshaped by a subsequent acute intestinal nematode co-infection. Immune cell subsets were characterized via flow cytometry in the brain of infected mice. Sulfadiazine and interferon-γ-neutralizing antibody were applied to subdue neuroinflammation. RESULTS: Neuroinflammation induced by T. gondii infection of mice was associated with increased microglia activation, recruitment of immune cells into the brain exhibiting Th1 effector functions, and enhanced production of Th1 and pro-inflammatory molecules (IFN-γ, iNOS, IL-12, TNF, IL-6, and IL-1ß) following co-infection with Heligmosomoides polygyrus. The accelerated cerebral Th1 immune response resulted in enhanced T. gondii removal but exacerbated the inflammation-related decrease of synapse-associated gene expression. Synaptic proteins EAAT2 and GABAAα1, which are involved in the excitation/inhibition balance in the CNS, were affected in particular. These synaptic alterations were partially recovered by reducing neuroinflammation indirectly via antiparasitic treatment and especially by application of IFN-γ-neutralizing antibody. Impaired iNOS expression following IFN-γ neutralization directly affected EAAT2 and GABAAα1 signaling, thus contributing to the microglial regulation of neurons. Besides, reduced CD36, TREM2, and C1qa gene expression points toward inflammation induced synaptic pruning as a fundamental mechanism. CONCLUSION: Our results suggest that neuroimmune responses following chronic T. gondii infection can be modulated by acute enteric nematode co-infection. While consecutive co-infection promotes parasite elimination in the CNS, it also adversely affects gene expression of synaptic proteins, via an IFN-γ-dependent manner.


Assuntos
Encéfalo/metabolismo , Interferon gama/metabolismo , Microglia/metabolismo , Neurônios/metabolismo , Infecções por Strongylida/metabolismo , Toxoplasmose/metabolismo , Animais , Encéfalo/parasitologia , Coinfecção , Ativação de Macrófagos/fisiologia , Camundongos , Microglia/parasitologia , Nematospiroides dubius , Neurônios/parasitologia , Sinapses/metabolismo , Sinapses/parasitologia , Toxoplasma
12.
J Immunol ; 196(9): 3532-6, 2016 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-26983785

RESUMO

In adult mice, lymphopenia-induced proliferation (LIP) leads to T cell activation, memory differentiation, tissue destruction, and a loss of TCR diversity. Neonatal mice are lymphopenic within the first week of life. This enables some recent thymic emigrants to undergo LIP and convert into long-lived memory T cells. Surprisingly, however, most neonatal T cells do not undergo LIP. We therefore asked whether neonate-specific mechanisms prevent lymphopenia-driven T cell activation. In this study, we show that IL-7R-dependent innate lymphoid cells (ILCs) block LIP of CD8(+) T cells in neonatal but not adult mice. Importantly, CD8(+) T cell responses against a foreign Ag are not inhibited by neonatal ILCs. This ILC-based inhibition of LIP ensures the generation of a diverse naive T cell pool in lymphopenic neonates that is mandatory for the maintenance of T cell homeostasis and immunological self-tolerance later in life.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Tolerância Imunológica , Memória Imunológica , Ativação Linfocitária , Linfopenia/imunologia , Transferência Adotiva , Animais , Animais Recém-Nascidos , Linfócitos T CD4-Positivos/imunologia , Diferenciação Celular , Proliferação de Células , Homeostase , Imunidade Inata , Camundongos , Camundongos Endogâmicos C57BL , Receptores de Interleucina-7/imunologia , Transdução de Sinais
13.
Environ Manage ; 62(5): 845-857, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30046845

RESUMO

Natural resources across the United States are increasingly managed at the landscape scale through cooperation among multiple organizations and landowners. United States Department of Agriculture Forest Service (USFS) agency leaders have widely promoted this approach since 2009 when Secretary of Agriculture Vilsack called for "all lands" management. Landscape scale projects have been undertaken to address multiple goals such as single species conservation, resilience to fire, invasive species eradication, and others. The West Virginia Restoration Venture (WVRV)-one of five landscape scale conservation projects funded 2014-2016 across the Northeast and Midwest and known as "Joint Chiefs'" projects-was evaluated by an interdisciplinary team of USFS employees to gain insight into how cross-boundary landscape scale conservation projects are implemented in the region. In this paper, the team used qualitative interview data from project participants to explore processes related to developing a shared vision for the landscape, implementation priorities, and methods to work across institutional and property ownership boundaries. Grounded in the landscape and collaborative resource management literatures, the report shows how established inter-organizational networks, flexible approaches to management, and a "shelf-stock" of ready-to-implement projects led to on-the-ground success. The authors provide insight about factors that constrain and facilitate the implementation of landscape scale conservation projects that have multiple goals, landowners, and organizational partners.


Assuntos
Conservação dos Recursos Naturais/métodos , Agricultura Florestal/organização & administração , Recursos Naturais , Região dos Apalaches , Conservação dos Recursos Naturais/legislação & jurisprudência , Comportamento Cooperativo , Incêndios/prevenção & controle , Agricultura Florestal/legislação & jurisprudência , Órgãos Governamentais , Propriedade , Resolução de Problemas , Estados Unidos , West Virginia
14.
J Immunol ; 194(2): 553-9, 2015 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-25480562

RESUMO

In response to primary Ag contact, naive mouse CD8(+) T cells undergo clonal expansion and differentiate into effector T cells. After pathogen clearance, most effector T cells die, and only a small number of memory T cell precursors (TMPs) survive to form a pool of long-lived memory T cells (TMs). Although high- and low-affinity CD8(+) T cell clones are recruited into the primary response, the TM pool consists mainly of high-affinity clones. It remains unclear whether the more efficient expansion of high-affinity clones and/or cell-intrinsic processes exclude low-affinity T cells from the TM pool. In this article, we show that the lack of IFN-γR signaling in CD8(+) T cells promotes TM formation in response to weak, but not strong, TCR agonists. The IFN-γ-sensitive accumulation of TMs correlates with reduced mammalian target of rapamycin activation and the accumulation of long-lived CD62L(hi)Bcl-2(hi)Eomes(hi) TMPs. Reconstitution of mammalian target of rapamycin or IFN-γR signaling is sufficient to block this process. Hence, our data suggest that IFN-γR signaling actively blocks the formation of TMPs responding to weak TCR agonists, thereby promoting the accumulation of high-affinity T cells finally dominating the TM pool.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Diferenciação Celular/imunologia , Memória Imunológica/fisiologia , Interferon gama/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Transdução de Sinais/imunologia , Animais , Diferenciação Celular/genética , Sobrevivência Celular/genética , Sobrevivência Celular/imunologia , Interferon gama/genética , Selectina L/genética , Selectina L/imunologia , Camundongos , Camundongos Knockout , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/imunologia , Receptores de Antígenos de Linfócitos T/genética , Receptores de Interferon/genética , Receptores de Interferon/imunologia , Transdução de Sinais/genética , Proteínas com Domínio T/genética , Proteínas com Domínio T/imunologia , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Receptor de Interferon gama
15.
Phys Rev Lett ; 115(1): 015501, 2015 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-26182104

RESUMO

By means of ab initio calculations combined to statistical mechanics, we provide new evidence that an experimentally undetectable tiny amount of impurities can be responsible for drastic changes in vacancy concentrations ([V]), inducing large deviations from an Arrhenius law even at low temperature. It is the case of O and N in α-Fe. The present finding is fully compatible with existing experiments, and changes the previous common vision that C has the dominant effect. This study provides a route for bridging the longstanding theoretical-experimental gap on the prediction of [V] in metals.

16.
Cell Commun Signal ; 12: 75, 2014 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-25477292

RESUMO

BACKGROUND: B cells are important effectors and regulators of adaptive and innate immune responses, inflammation and autoimmunity, for instance in anti-NMDA-receptor (NMDAR) encephalitis. Thus, pharmacological modulation of B-cell function could be an effective regimen in therapeutic strategies. Since the non-competitive NMDAR antagonist memantine is clinically applied to treat advanced Alzheimer`s disease and ketamine is supposed to improve the course of resistant depression, it is important to know how these drugs affect B-cell function. RESULTS: Non-competitive NMDAR antagonists impaired B-cell receptor (BCR)- and lipopolysaccharide (LPS)-induced B-cell proliferation, reduced B-cell migration towards the chemokines SDF-1α and CCL21 and downregulated IgM and IgG secretion. Mechanistically, these effects were mediated through a blockade of Kv1.3 and KCa3.1 potassium channels and resulted in an attenuated Ca(2+)-flux and activation of Erk1/2, Akt and NFATc1. Interestingly, NMDAR antagonist treatment increased the frequency of IL-10 producing B cells after BCR/CD40 stimulation. CONCLUSIONS: Non-competitive NMDAR antagonists attenuate BCR and Toll-like receptor 4 (TLR4) B-cell signaling and effector function and can foster IL-10 production. Consequently, NMDAR antagonists may be useful to target B cells in autoimmune diseases or pathological systemic inflammation. The drugs' additional side effects on B cells should be considered in treatments of neuronal disorders with NMDAR antagonists.


Assuntos
Linfócitos B/efeitos dos fármacos , Interleucina-10/metabolismo , Piperidinas/farmacologia , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Animais , Apoptose/efeitos dos fármacos , Linfócitos B/metabolismo , Antígenos CD40/metabolismo , Proliferação de Células/efeitos dos fármacos , Imunoglobulina G/metabolismo , Imunoglobulina M/metabolismo , Interferon gama/metabolismo , Interleucina-10/genética , Canais de Potássio Ativados por Cálcio de Condutância Intermediária/metabolismo , Canal de Potássio Kv1.3/metabolismo , Lipopolissacarídeos/farmacologia , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Receptores de Antígenos de Linfócitos B/metabolismo , Receptor 4 Toll-Like/metabolismo
17.
J Spine Surg ; 10(2): 165-176, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38974499

RESUMO

Background: Traditional surgical treatment for symptomatic cervical degenerative disc disease is anterior cervical discectomy and fusion (ACDF), yet the increased risk of adjacent segment degeneration (ASD) requiring additional surgery exists and may result in limiting long-term surgical success when it occurs. Disc arthroplasty can preserve or restore physiologic range of motion (ROM), decreasing adjacent level stress and subsequent surgery. For patients with multilevel pathology requiring at least a 1-level fusion, interest is growing in anterior cervical hybrid (ACH) surgery as a partial motion-preserving procedure to decrease the adjacent level burden. This radiographic study compares postoperative superior adjacent segment motion between ACH and ACDF. Secondarily, total global motion, construct motion, inferior adjacent segment motion, and sagittal alignment parameters were compared. Methods: This is a single-center, multi-surgeon, retrospective cohort study of 2- and 3-level ACH and ACDF cases between 2013 and 2021. Degrees of motion were analyzed on flexion/extension views using Cobb angles to measure global (C2-C7) construct and adjacent segment lordosis. Neutral lateral X-rays were analyzed for alignment parameters, including global lordosis, cervical sagittal vertical axis (cSVA), and T1 slope (T1S). Differences were determined by independent t-test and Fisher's exact test. Results: Of 100 patients, 38% were 2-level cases (47% ACH, 53% ACDF) and 62% were 3-level cases: (52% ACH, 48% ACDF). Postoperatively, superior adjacent segment motion increased with ACDF and decreased with ACH (-1.3°±5.3° ACH, 1.6°±4.6° ACDF, P=0.005). Postoperatively, the ACH group had greater ROM across the construct (16.3°±8.7° ACH, 4.7°±3.3° ACDF, P<0.001) and total global ROM (38.0°±12.8° ACH, 28.0°±11.1° ACDF, P<0.001). ACH resulted in a significant reduction of motion loss across the construct (-10.0°±11.7° ACH, -18.1°±10.8° ACDF, P<0.001). Postoperative alignment restoration was similar between both cohorts (-2.61°±8.36° ACH, 0.04°±12.24° ACDF, P=0.21). Conclusions: Compared to ACDF, hybrid constructs partially preserved motion across operative levels and had greater postoperative global ROM without increasing superior adjacent segment mobility or sacrificing alignment restoration. This supports the consideration of ACH in patients with multilevel degenerative cervical pathology requiring at least a 1-level fusion and suggests a propensity for long-term success by reducing the superior adjacent segment burden.

18.
Global Spine J ; 13(7): 2047-2052, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35000409

RESUMO

STUDY DESIGN: Prospective cohort study. OBJECTIVES: In spine surgery, accurate screw guidance is critical to achieving satisfactory fixation. Augmented reality (AR) is a novel technology to assist in screw placement and has shown promising results in early studies. This study aims to provide our early experience evaluating safety and efficacy with an Food and Drug Administration-approved head-mounted (head-mounted device augmented reality (HMD-AR)) device. METHODS: Consecutive adult patients undergoing AR-assisted thoracolumbar fusion between October 2020 and August 2021 with 2 -week follow-up were included. Preoperative, intraoperative, and postoperative data were collected to include demographics, complications, revision surgeries, and AR performance. Intraoperative 3D imaging was used to assess screw accuracy using the Gertzbein-Robbins (G-R) grading scale. RESULTS: Thirty-two patients (40.6% male) were included with a total of 222 screws executed using HMD-AR. Intraoperatively, 4 (1.8%) were deemed misplaced and revised using AR or freehand. The remaining 218 (98.2%) screws were placed accurately. There were no intraoperative adverse events or complications, and AR was not abandoned in any case. Of the 208 AR-placed screws with 3D imaging confirmation, 97.1% were considered clinically accurate (91.8% Grade A, 5.3% Grade B). There were no early postoperative surgical complications or revision surgeries during the 2 -week follow-up. CONCLUSIONS: This early experience study reports an overall G-R accuracy of 97.1% across 218 AR-guided screws with no intra or early postoperative complications. This shows that HMD-AR-assisted spine surgery is a safe and accurate tool for pedicle, cortical, and pelvic fixation. Larger studies are needed to continue to support this compelling evolution in spine surgery.

19.
Global Spine J ; 13(4): 1030-1035, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-34018420

RESUMO

STUDY DESIGN: Retrospective observational cohort. OBJECTIVES: We sought to evaluate the impact of ESR on in-hospital and 90-day postoperative opioid consumption, length of stay, urinary catheter removal and postoperative ambulation after lumbar fusion for degenerative conditions. METHODS: We evaluated patients undergoing lumbar fusion surgery at a single, multi-surgeon center in the transition period prior to (N = 174) and after (N = 116) adoption of ESR, comparing in-hospital and 90-day postoperative opioid consumption. Regression analysis was used to control for confounders. Secondary analysis was preformed to evaluate the association between ESR and length of stay, urinary catheter removal and ambulation after surgery. RESULTS: Mean age study participants was 52.6 years with 62 (47%) females. Demographic characteristics were similar between the Pre-ESR and ESR groups. ESR patients had better 3-month pain scores, ambulated earlier, had urinary catheters removed earlier and decreased in-hospital opioid consumption compared to Pre-ESR patients. There was no difference in 90-day opioid consumption between the 2 groups. Regression analysis showed that ESR was strongly associated with in-hospital opioid consumption, accounting for 30% of the variability in Morphine Milligram Equivalents (MME). In-hospital opioid consumption was also associated with preoperative pain scores, number of surgical levels, and insurance type (private vs government). Pre-op pain sores were associated with 90-day opioid consumption. Secondary analysis showed that ESR was associated with a shorter length of stay and earlier ambulation. CONCLUSIONS: This study showed ESR has the potential to improve recovery after lumbar fusion for degenerative conditions with reduced in-hospital opioid consumption and improved postoperative pain scores.

20.
Blood ; 115(11): 2196-202, 2010 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-20075162

RESUMO

Functional inactivation of self-reactive T lymphocytes contributes to the maintenance of immunologic self-tolerance. At the same time, tolerance induction limits immune responses against tumors expressing tolerizing self-antigens. Some cancer therapies include the adoptive transfer of tumor-reactive T lymphocytes into lymphopenic patients. Lymphopenia provides an activation signal to T lymphocytes, which undergo lymphopenia-induced proliferation (LIP), acquire effector functions, and reject tumors. However, it is so far unknown to which extent LIP may result in reversal of established antigen-specific CD8 T-cell tolerance. Here, we report that neonatally induced dominant CD8 T-cell tolerance remained stable under lymphopenic conditions also in the presence of systemic inflammation induced by Toll-like receptor ligands. However, when lymphopenic recipients were irradiated, the tolerant status was lost, because CD8 T cells acquired effector functions in an interleukin-15-dependent fashion and efficiently rejected tumors. In conclusion, we show that lymphopenia is not sufficient to break CD8 T-cell tolerance. Furthermore, we demonstrate that pretreatment regimens are crucial to circumvent this problem and to optimize adoptive T-cell therapy.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/efeitos da radiação , Tolerância Imunológica/imunologia , Tolerância Imunológica/efeitos da radiação , Interleucina-15/imunologia , Linfopenia/imunologia , Irradiação Corporal Total , Transferência Adotiva , Animais , Antígenos/imunologia , Divisão Celular/efeitos da radiação , Proliferação de Células/efeitos da radiação , Homeostase/imunologia , Homeostase/efeitos da radiação , Receptores de Hialuronatos/metabolismo , Inflamação/imunologia , Camundongos , Timectomia
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