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1.
Sci Adv ; 9(44): eadh1106, 2023 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-37910606

RESUMO

Paleoclimate proxy records from the North Atlantic region reveal substantially greater multicentennial temperature variability during the Last Glacial Maximum (LGM) compared to the current interglacial. As there was no obvious change in external forcing, causes for the increased variability remain unknown. Exploiting LGM simulations with a comprehensive coupled climate model along with high-resolution proxy records, we introduce an oscillatory mode of multicentennial variability, which is associated with moderate variations in the Atlantic meridional overturning circulation and depends on the large-scale salinity distribution. This self-sustained mode is amplified by sea-ice feedbacks and induces maximum surface temperature variability in the subpolar North Atlantic region. Characterized by a distinct climatic imprint and different dynamics, the multicentennial oscillation has to be distinguished from Dansgaard-Oeschger variability and emerges only under full LGM climate forcing. The potential of multicentennial modes of variability to emerge or disappear in response to changing climate forcing may have implications for future climate change.

2.
Nat Immunol ; 24(11): 1921-1932, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37813964

RESUMO

The malate shuttle is traditionally understood to maintain NAD+/NADH balance between the cytosol and mitochondria. Whether the malate shuttle has additional functions is unclear. Here we show that chronic viral infections induce CD8+ T cell expression of GOT1, a central enzyme in the malate shuttle. Got1 deficiency decreased the NAD+/NADH ratio and limited antiviral CD8+ T cell responses to chronic infection; however, increasing the NAD+/NADH ratio did not restore T cell responses. Got1 deficiency reduced the production of the ammonia scavenger 2-ketoglutarate (2-KG) from glutaminolysis and led to a toxic accumulation of ammonia in CD8+ T cells. Supplementation with 2-KG assimilated and detoxified ammonia in Got1-deficient T cells and restored antiviral responses. These data indicate that the major function of the malate shuttle in CD8+ T cells is not to maintain the NAD+/NADH balance but rather to detoxify ammonia and enable sustainable ammonia-neutral glutamine catabolism in CD8+ T cells during chronic infection.


Assuntos
Ácidos Cetoglutáricos , NAD , Humanos , Oxirredução , NAD/metabolismo , Ácidos Cetoglutáricos/metabolismo , Amônia , Malatos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Infecção Persistente , Antivirais
3.
J Mater Chem B ; 11(35): 8449-8455, 2023 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-37580990

RESUMO

Intravenous chemotherapy (e.g., doxorubicin (DOX)) is standard treatment for many cancers but also leads to side effects due to off-target toxicity. To address this challenge, devices for removing off-target chemotherapy agents from the bloodstream have been developed, but the efficacy of such devices relies on the ability of the underlying materials to specifically sequester small-molecule drugs. Anion-exchange materials, genomic DNA, and DNA-functionalized iron oxide particles have all been explored as drug-capture materials, but cost, specificity, batch-to-batch variation, and immunogenicity concerns persist as challenges. Here, we report a new class of fully synthetic drug-capture materials. We copolymerized methacrylic acid and ethylene glycol dimethacrylate in the presence of several nucleobases and derivatives (adenine, cytosine, xanthine, and thymine) to yield a crosslinked resin with nucleobases integrated into the material. These materials demonstrated effective DOX capture: up to 27 mg of DOX per g of material over 20 minutes from a phosphate-buffered saline solution with an initial concentration of 0.05 mg mL-1 of DOX. These materials use only the individual nucleobases for DOX capture and exhibit competitive capture efficacy compared to previous materials that used genomic DNA, making this approach more cost-effective and reducing potential immunological concerns.


Assuntos
Antineoplásicos , Polímeros , Sistemas de Liberação de Medicamentos , Polietilenoglicóis/uso terapêutico , Antineoplásicos/uso terapêutico , Doxorrubicina/farmacologia , DNA
4.
Musculoskelet Sci Pract ; 66: 102812, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37414673

RESUMO

BACKGROUND: Despite neck pain being a common complaint for people with migraine, little is known about how individuals perceive the relationship between their migraine and neck pain. Exploring their beliefs and perceptions could provide valuable understanding to improve overall management and reduce the burden of migraine and neck pain. OBJECTIVES: To investigate individual perspectives on how migraine and neck pain relate. METHODS: A retrospective qualitative study was performed. Seventy participants (mean age 39.2, 60 female) were recruited via community and social media advertisements, and interviewed by an experienced physiotherapist using a semi-structured interview framework. An Inductive thematic analysis was used to analyse the responses. RESULTS: Five themes were identified from the interviews: (i) the timing of neck pain and migraine, (ii) causality beliefs, (iii) burden of neck pain and migraine, (iv) experiences with treatment and (v) mismatched perspectives. Diverse views emerged, revealing links between the first two themes of timing and causality, showing increased burden in those suffering from both neck pain and migraine, and providing insights into apparently ineffective or even aggravating treatments. CONCLUSIONS: Valuable insights for clinicians emerged. Due to the complex relationship, clinicians should discuss the aetiology of neck pain in migraine with patients. For some individuals, neck treatment may not produce long-term relief and may even aggravate migraine, but the value of short-term relief in a chronic condition must be considered individually. Clinicians are ideally placed to have discussions with patients individually to tailor individual decisions about management.


Assuntos
Transtornos de Enxaqueca , Cervicalgia , Humanos , Feminino , Estudos Retrospectivos , Transtornos de Enxaqueca/terapia , Doença Crônica , Pesquisa Qualitativa
5.
Angew Chem Int Ed Engl ; 62(22): e202302303, 2023 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-37078735

RESUMO

Inducing high levels of reactive oxygen species (ROS) inside tumor cells is a cancer therapy method termed chemodynamic therapy (CDT). Relying on delivery of Fenton reaction promoters such as Fe2+ , CDT takes advantage of overproduced ROS in the tumor microenvironment. We developed a peptide-H2 S donor conjugate, complexed with Fe2+ , termed AAN-PTC-Fe2+ . The AAN tripeptide was specifically cleaved by legumain, an enzyme overexpressed in glioma cells, to release carbonyl sulfide (COS). Hydrolysis of COS by carbonic anhydrase formed H2 S, an inhibitor of catalase, an enzyme that detoxifies H2 O2 . Fe2+ and H2 S together increased intracellular ROS levels and decreased viability in C6 glioma cells compared with controls lacking either Fe2+ , the AAN sequence, or the ability to generate H2 S. AAN-PTC-Fe2+ performed better than temezolimide while exhibiting no cytotoxicity toward H9C2 cardiomyocytes. This study provides an H2 S-amplified, enzyme-responsive platform for synergistic cancer treatment.


Assuntos
Glioma , Nanopartículas , Neoplasias , Humanos , Espécies Reativas de Oxigênio , Peptídeos/farmacologia , Linhagem Celular Tumoral , Microambiente Tumoral , Peróxido de Hidrogênio
6.
Psychiatr Prax ; 50(2): 98-102, 2023 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-36455601

RESUMO

OBJECTIVE: Evaluation of long-term effects of the implementation of the Safewards Model (SM) among staff and patients in acute psychiatry in Germany. METHOD: Assessment of ward atmosphere, job satisfaction, fidelity, and coercive interventions in 2 locked wards directly before and 15 months after implementation of the SM. RESULTS: Ward atmosphere was assessed significantly better after implementation, job satisfaction was still above-average at both times, coercive interventions declined significantly in one ward, fidelity and degree of implementation were still high. CONCLUSIONS: The implementing of the SM in locked wards in acute psychiatry can also have positive effects in long run.


Assuntos
Unidade Hospitalar de Psiquiatria , Psiquiatria , Humanos , Seguimentos , Alemanha , Coerção
7.
J Chem Inf Model ; 63(7): 2030-2036, 2023 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-36533730

RESUMO

Polymers make the basis of highly tunable materials that could be designed and optimized for metal recovery from aqueous environments. While experimental studies show that this approach has potential, it suffers from a limited knowledge of the detailed molecular interaction between polymers and target metal ions. Here, we propose to calculate intrinsic electric fields from polarizable force field molecular dynamics simulations to characterize the driving force behind Eu3+ motion in the presence of poly(ethylenimine methylenephosphonate), a specifically designed metal chelating polymer. Focusing on the metal chelation initiation step (i.e., before binding), we can rationalize the role of each molecule on ion dynamics by projecting these electric fields along the direction of ion motion. We find that the polymer functional groups act indirectly, and the polymer-metal ion interaction is actually mediated by water. This result is consistent with the experimental observation that metal sequestration by these polymers is entropically driven. This study suggests that electric field calculations can help the design of metal chelating polymers, for example, by seeking to optimize polymer-solvent interactions rather than polymer-ion interactions.


Assuntos
Polímeros , Água , Polímeros/química , Água/química , Solventes/química , Fenômenos Mecânicos , Íons/química
8.
Nat Commun ; 13(1): 6099, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-36243867

RESUMO

The electrochemical reduction of CO2 is a pivotal technology for the defossilization of the chemical industry. Although pilot-scale electrolyzers exist, water management and salt precipitation remain a major hurdle to long-term operation. In this work, we present high-resolution neutron imaging (6 µm) of a zero-gap CO2 electrolyzer to uncover water distribution and salt precipitation under application-relevant operating conditions (200 mA cm-2 at a cell voltage of 2.8 V with a Faraday efficiency for CO of 99%). Precipitated salts penetrating the cathode gas diffusion layer can be observed, which are believed to block the CO2 gas transport and are therefore the major cause for the commonly observed decay in Faraday efficiency. Neutron imaging further shows higher salt accumulation under the cathode channel of the flow field compared to the land.

9.
BMC Nephrol ; 23(1): 317, 2022 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-36131241

RESUMO

BACKGROUND: In centre haemodialysis (ICHD) patients have been identified as high risk of contracting Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection due to frequent healthcare contact and poor innate and adaptive immunity. Our ICHD patients were offered immunisation from January 2021. We aimed to assess outcomes following SARS-CoV-2 infection and report on the effect of vaccination in our ICHD patients. METHODS: Demographics, SARS-CoV-2 status, hospitalisation, mortality and vaccination status were analysed. From 11th March 2020 to 31st March 2021, 662 ICHD patients were included in the study and these patients were then followed up until 31st August 2021. RESULTS: SARS-CoV-2 infection occurred in 28.4% with 51.1% of them requiring hospitalisation in contrast to community infection rates of 13.9% and hospitalisation of 9.0%. 28-day mortality was 19.2% in comparison to 1.9% of the community. Mortality increased to 34.0% over the study period. Mortality over the study period was 1.8 times in infected patients (HR 1.81 (1.32-2.49) P < 0.001) despite adjustment for age, gender and ethnicity. 91.3% of ICHD patients have now received both doses of SARS-CoV-2 vaccinations. CONCLUSIONS: ICHD patients are at increased risk of acquiring SARS-CoV-2, with increased rates of hospitalisation and mortality. The increased mortality extends well beyond the 28 days post-infection and persists in those who have recovered. Peaks and troughs in infection rates mirrored community trends. Preliminary data indicates that the SARS-CoV-2 vaccination provides protection to ICHD patients, with ICHD case rates now comparable to that of the local population.


Assuntos
COVID-19 , SARS-CoV-2 , COVID-19/epidemiologia , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Humanos , Diálise Renal , Vacinação
10.
RSC Adv ; 12(32): 20778-20784, 2022 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-35919174

RESUMO

Dry cathode operation is a desired operation mode in anion-exchange membrane water electrolyzers to minimize contamination of the generated hydrogen. However, water management under such operation conditions makes it challenging to maintain reliable performance and durability. Here, we utilize high-resolution in situ neutron imaging (∼6 µm effective resolution) to analyze the water content inside the membrane-electrode-assembly of an anion-exchange membrane water electrolyzer. The ion-exchange capacity (IEC) and thus hydrophilicity of the polymer binder in the cathode catalyst layer is varied to study the influence on water content in the anode (mid IEC, 1.8-2.2 meq. g-1 and high IEC, 2.3-2.6 meq. g-1). The neutron radiographies show that a higher ion-exchange capacity binder allows improved water retention, which reduces the drying-out of the cathode at high current densities. Electrochemical measurements confirm a generally better efficiency for a high IEC cell above 600 mA cm-2. At 1.5 A cm-2 the high IEC has a 100 mV lower overpotential (2.1 V vs. 2.2 V) and a lower high frequency resistance (210 mΩ cm-2 vs. 255 mΩ cm-2), which is believed to be linked to the improved cathode water retention and membrane humidification. As a consequence, the performance stability of the high IEC cell at 1 A cm-2 is also significantly better than that of the mid IEC cell (45 mV h-1 vs. 75 mV h-1).

11.
PLoS One ; 17(6): e0269157, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35653415

RESUMO

Tau protein is a key target of interest in developing therapeutics for neurodegenerative diseases. Here, we sought to develop a method that quantifies extracellular tau protein concentrations in human cerebrospinal fluid (CSF) without antibody-based enrichment strategies. We demonstrate that the fit-for-purpose validated method in Alzheimer's Disease CSF is limited to quasi quantitative measures of tau surrogate peptides. We also provide evidence that CSF total Tau measures by LC-MS are feasible in the presence of monoclonal therapeutic antibodies in human CSF. Our Tau LC-MS/MS method is a translational bioanalytical tool for assaying target engagement and pharmacodynamics for anti-tau antibody drug development campaigns.


Assuntos
Doença de Alzheimer , Proteínas tau , Doença de Alzheimer/líquido cefalorraquidiano , Anticorpos Monoclonais , Cromatografia Líquida/métodos , Humanos , Espectrometria de Massas em Tandem/métodos , Proteínas tau/líquido cefalorraquidiano
12.
Eur J Pharm Biopharm ; 176: 188-198, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35598767

RESUMO

Clogging of staked-in-needle prefilled syringes (PFS) is a sporadic and scarcely predictable event, which occurs particularly in highly concentrated protein solutions and can result in the injection of incomplete doses, especially if autoinjector devices are used for administration. A systematic screening of possible causes and triggers was performed in order to find the crucial factors of influence, the underlying mechanisms and possible measures for prevention. An essential prerequisite for the formation of a solidified clog in the needle is the ingress of liquid from the barrel, which was investigated and quantified by means of neutron imaging after storage of prefilled syringes under various conditions. The needle filling ratio increases with both the storage temperature and the storage period, as a result of atmospheric gas diffusion through the needle shield. While the air pocket in the needle is reduced by this process, diffusion of water vapor does not affect the filling ratio but instead increases the protein concentration in the needle lumen, leading to an exponential rise of the viscosity and finally to the solidification of the protein solution. Maintaining the air pocket in the needle by avoiding any diffusion promoting pressure gradient is therefore the most effective protection from clogging.


Assuntos
Agulhas , Seringas , Injeções , Vapor , Viscosidade
13.
Phys Chem Chem Phys ; 24(6): 3579-3585, 2022 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-35088772

RESUMO

Metal-chelating polymers play a key role in rare-earth element (REE) extraction and separation processes. Often, these processes occur in aqueous solution, but the interactions among water, polymer, and REE are largely under-investigated in these applications. To probe these interactions, we synthesized a series of poly(amino acid acrylamide)s with systematically varied hydrophobicity around a consistent chelating group (carboxylate). We then measured the ΔH of Eu3+ chelation as a function of temperature across the polymer series using isothermal titration calorimetry (ITC) to give the change in heat capacity (ΔCP). We observed an order of magnitude variation in ΔCP (39-471 J mol1 K-1) with changes in the hydrophobicity of the polymer. Atomistic simulations of the polymer-metal-water interactions revealed greater Eu3+ and polymer desolvation when binding to the more hydrophobic polymers. These combined experimental and computational results demonstrate that metal binding in aqueous solution can be modulated not only by directly modifying the chelating groups, but also by altering the molecular environment around the chelating site, thus suggesting a new design principle for developing increasingly effective metal-chelating materials.


Assuntos
Polímeros , Calorimetria , Interações Hidrofóbicas e Hidrofílicas , Ligação Proteica , Temperatura , Termodinâmica
14.
Nervenarzt ; 93(5): 450-458, 2022 May.
Artigo em Alemão | MEDLINE | ID: mdl-34905064

RESUMO

OBJECTIVE: To investigate whether implementation recommendations derived from the German guidelines "Prevention of coercion" can be implemented on acute psychiatric wards by means of implementation consultants into ward work and if this contributes to an increased level of adherence to guideline intervention recommendations approved by the DGPPN (Deutsche Gesellschaft für Psychiatrie und Psychotherapie, Psychosomatik und Nervenheilkunde)? MATERIAL AND METHODS: Two medical or nursing experts advised ward teams on the implementation of three individually selected recommendations from the guidelines in a structured consulting process over 6 months. The degree of implementation of the recommendations was assessed before and after the intervention by the ward teams together with the implementation consultants using a tool developed for this purpose (PreVCo rating tool). RESULTS: A total of five wards responsible for compulsorily admitted patients took part in the pilot study; three of them completed the intervention. On all three wards, implementation of the guideline recommendations improved for both selected and unselected recommendations. The strategy of using implementation consultants as well as the application of the PreVCo rating tool were well accepted and considered feasible by both the treatment teams and the implementation consultants. CONCLUSION: This pilot study showed that an implementation of recommendations on psychiatric wards derived from the German guidelines "Prevention of coercion" supported by implementation consultants is feasible, well acceptable among treatment teams and can lead to positive changes. The sample of five wards with diverse patient profiles was convincing. The efficacy in terms of reduction of coercive measures is currently being investigated in a randomized controlled trial on 55 psychiatric wards in different parts of Germany, with an intervention based on this pilot study.


Assuntos
Coerção , Unidade Hospitalar de Psiquiatria , Adulto , Agressão , Alemanha , Humanos , Projetos Piloto
15.
J Imaging ; 7(10)2021 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-34677295

RESUMO

Grating-based phase-contrast and dark-field imaging systems create intensity modulations that are usually modeled with sinusoidal functions to extract transmission, differential-phase shift, and scatter information. Under certain system-related conditions, the modulations become non-sinusoidal and cause artifacts in conventional processing. To account for that, we introduce a piecewise-defined periodic polynomial function that resembles the physical signal formation process, modeling convolutions of binary periodic functions. Additionally, we extend the model with an iterative expectation-maximization algorithm that can account for imprecise grating positions during phase-stepping. We show that this approach can process a higher variety of simulated and experimentally acquired data, avoiding most artifacts.

16.
Front Immunol ; 12: 716504, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34539650

RESUMO

Macrophages not only represent an integral part of innate immunity but also critically contribute to tissue and organ homeostasis. Moreover, disease progression is accompanied by macrophage accumulation in many cancer types and is often associated with poor prognosis and therapy resistance. Given their critical role in modulating tumor immunity in primary and metastatic brain cancers, macrophages are emerging as promising therapeutic targets. Different types of macrophages infiltrate brain cancers, including (i) CNS resident macrophages that comprise microglia (TAM-MG) as well as border-associated macrophages and (ii) monocyte-derived macrophages (TAM-MDM) that are recruited from the periphery. Controversy remained about their disease-associated functions since classical approaches did not reliably distinguish between macrophage subpopulations. Recent conceptual and technological advances, such as large-scale omic approaches, provided new insight into molecular profiles of TAMs based on their cellular origin. In this review, we summarize insight from recent studies highlighting similarities and differences of TAM-MG and TAM-MDM at the molecular level. We will focus on data obtained from RNA sequencing and mass cytometry approaches. Together, this knowledge significantly contributes to our understanding of transcriptional and translational programs that define disease-associated TAM functions. Cross-species meta-analyses will further help to evaluate the translational significance of preclinical findings as part of the effort to identify candidates for macrophage-targeted therapy against brain metastasis.


Assuntos
Neoplasias Encefálicas/imunologia , Neoplasias Encefálicas/patologia , Microglia/imunologia , Microambiente Tumoral/imunologia , Macrófagos Associados a Tumor/imunologia , Animais , Biomarcadores , Neoplasias Encefálicas/secundário , Suscetibilidade a Doenças , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Microglia/metabolismo , Transcriptoma , Macrófagos Associados a Tumor/metabolismo
17.
BMC Geriatr ; 21(1): 222, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33794789

RESUMO

BACKGROUND: Most people with dementia (PwD) are cared for at home, with general practitioners (GPs) playing a key part in the treatment. However, primary dementia care suffers from a number of shortcomings: Often, diagnoses are made too late and therapies by GPs do not follow the guidelines. In cases of acute crises, PwD are too often admitted to hospital with adverse effects on the further course of the disease. The aim of this study is to implement and evaluate a new GP-based, complex dementia care model, DemStepCare. DemStepCare aims to ensure demand-oriented, stepped care for PwD and their caregivers. METHODS/DESIGN: In a cluster randomized controlled trial, the care of PwD receiving a complex intervention, where the GP is supported by a multi-professional team, is compared to (slightly expanded) usual care. GPs are clustered by GP practice, with 120 GP practices participating in total. GP practices are randomized to an intervention or a control group. 800 PwD are to be included per group. Recruitment takes place in Rhineland-Palatinate, Germany. In addition, a second control group with at least 800 PwD will be formed using aggregated routine data from German health insurance companies. The intervention comprises the training of GPs, case management including repeated risk assessment of the patients' care situation, the demand-oriented service of an outpatient clinic, an electronic case record, external medication analyses and a link to regional support services. The primary aims of the intervention are to positively influence the quality of life for PwD, to reduce the caregivers' burden, and to reduce the days spent in hospital. Secondary endpoints address medication adequacy and GPs' attitudes and sensitivity towards dementia, among others. DISCUSSION: The GP-based dementia care model DemStepCare is intended to combine a number of promising interventions to provide a complex, stepped intervention that follows the individual needs of PwD and their caregivers. Its effectiveness and feasibility will be assessed in a formative and a summative evaluation. TRIAL REGISTRATION: German Register of Clinical Trials (Deutsches Register Klinischer Studien, DRKS), DRKS00023560 . Registered 13 November 2020 - Retrospectively registered. HTML&TRIAL_ID=DRKS00023560.


Assuntos
Demência , Qualidade de Vida , Cuidadores , Demência/diagnóstico , Demência/terapia , Alemanha , Humanos , Atenção Primária à Saúde , Ensaios Clínicos Controlados Aleatórios como Assunto
18.
EMBO Mol Med ; 13(5): e13412, 2021 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-33755340

RESUMO

The tumor microenvironment in brain metastases is characterized by high myeloid cell content associated with immune suppressive and cancer-permissive functions. Moreover, brain metastases induce the recruitment of lymphocytes. Despite their presence, T-cell-directed therapies fail to elicit effective anti-tumor immune responses. Here, we seek to evaluate the applicability of radio-immunotherapy to modulate tumor immunity and overcome inhibitory effects that diminish anti-cancer activity. Radiotherapy-induced immune modulation resulted in an increase in cytotoxic T-cell numbers and prevented the induction of lymphocyte-mediated immune suppression. Radio-immunotherapy led to significantly improved tumor control with prolonged median survival in experimental breast-to-brain metastasis. However, long-term efficacy was not observed. Recurrent brain metastases showed accumulation of blood-borne PD-L1+ myeloid cells after radio-immunotherapy indicating the establishment of an immune suppressive environment to counteract re-activated T-cell responses. This finding was further supported by transcriptional analyses indicating a crucial role for monocyte-derived macrophages in mediating immune suppression and regulating T-cell function. Therefore, selective targeting of immune suppressive functions of myeloid cells is expected to be critical for improved therapeutic efficacy of radio-immunotherapy in brain metastases.


Assuntos
Neoplasias Encefálicas , Microambiente Tumoral , Neoplasias Encefálicas/radioterapia , Humanos , Imunoterapia , Macrófagos , Células Mieloides
19.
Nat Commun ; 12(1): 277, 2021 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-33436592

RESUMO

Uncertainty in the representation of biomass burning (BB) aerosol composition and optical properties in climate models contributes to a range in modeled aerosol effects on incoming solar radiation. Depending on the model, the top-of-the-atmosphere BB aerosol effect can range from cooling to warming. By relating aerosol absorption relative to extinction and carbonaceous aerosol composition from 12 observational datasets to nine state-of-the-art Earth system models/chemical transport models, we identify varying degrees of overestimation in BB aerosol absorptivity by these models. Modifications to BB aerosol refractive index, size, and mixing state improve the Community Atmosphere Model version 5 (CAM5) agreement with observations, leading to a global change in BB direct radiative effect of -0.07 W m-2, and regional changes of -2 W m-2 (Africa) and -0.5 W m-2 (South America/Temperate). Our findings suggest that current modeled BB contributes less to warming than previously thought, largely due to treatments of aerosol mixing state.

20.
Nat Cancer ; 2(10): 1086-1101, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-35121879

RESUMO

Tumor microenvironment-targeted therapies are emerging as promising treatment options for different cancer types. Tumor-associated macrophages and microglia (TAMs) represent an abundant nonmalignant cell type in brain metastases and have been proposed to modulate metastatic colonization and outgrowth. Here we demonstrate that targeting TAMs at distinct stages of the metastatic cascade using an inhibitor of colony-stimulating factor 1 receptor (CSF1R), BLZ945, in murine breast-to-brain metastasis models leads to antitumor responses in prevention and intervention preclinical trials. However, in established brain metastases, compensatory CSF2Rb-STAT5-mediated pro-inflammatory TAM activation blunted the ultimate efficacy of CSF1R inhibition by inducing neuroinflammation gene signatures in association with wound repair responses that fostered tumor recurrence. Consequently, blockade of CSF1R combined with inhibition of STAT5 signaling via AC4-130 led to sustained tumor control, a normalization of microglial activation states and amelioration of neuronal damage.


Assuntos
Neoplasias Encefálicas , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Receptores de Fator Estimulador das Colônias de Granulócitos e Macrófagos , Animais , Neoplasias Encefálicas/secundário , Genes fms , Ativação de Macrófagos , Melanoma , Camundongos , Receptores de Fator Estimulador de Colônias/metabolismo , Receptores de Fator Estimulador das Colônias de Granulócitos e Macrófagos/genética , Fator de Transcrição STAT5/genética , Neoplasias Cutâneas , Microambiente Tumoral , Melanoma Maligno Cutâneo
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