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1.
Cancers (Basel) ; 16(5)2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38473343

RESUMO

INTRODUCTION: Even in times of new therapy regimes, the overall survival of patients with head and neck cancer remains low. Since the previous studies showed the beneficial effect of metformin medication on the survival of patients with cancer, our objective was to investigate if-and in which way-metformin medication affects the overall survival of patients with head and neck cancer. METHODS: Clinical data pertaining to patients diagnosed with head and neck cancer (International Classification of Diseases 10 codes C00-C14, C31, and C32) were retrospectively retrieved from the TriNetX network (TriNetX, Cambridge, MA, USA). The initial cohort extracted from the network was stratified into two groups: patients on metformin medication (cohort I), and individuals not on metformin medication (cohort II). The matching criteria included age, gender, BMI, type 2 diabetes, and risk factors, such as nicotine and alcohol abuse/dependence. Kaplan-Meier analysis, risk analysis, and the calculation of odds and hazard ratios were conducted. Additionally, the Hemoglobin A1c values were subject to analysis. RESULTS: Following matching, each cohort comprised 20,416 patients. Cohort I exhibited a higher five-year survival rate at 75.3%, in contrast to cohort II, which registered a rate of 69.8%. The odds ratio was 0.79 (95% CI = 0.75-0.83), and the hazard ratio was 0.78 (95% CI = 0.75-0.82). CONCLUSION: Metformin medication may correlate with improved five-year survival rates in patients with head and neck cancer. Since potentially influencing factors such as comorbidities and the initial tumor stage were not available, the results of our retrospectively conducted study must be interpreted with caution.

3.
Cells ; 13(4)2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38391912

RESUMO

Platelet function at vascular injury sites is tightly regulated through the actin cytoskeleton. The Wiskott-Aldrich syndrome protein-family verprolin-homologous protein (WAVE)-regulatory complex (WRC) activates lamellipodia formation via ARP2/3, initiated by GTP-bound RAC1 interacting with the WRC subunit CYFIP1. The protein FAM49b (Family of Unknown Function 49b), also known as CYRI-B (CYFIP-Related RAC Interactor B), has been found to interact with activated RAC1, leading to the negative regulation of the WRC in mammalian cells. To investigate the role of FAM49b in platelet function, we studied platelet-specific Fam49b-/--, Cyfip1-/--, and Cyfip1/Fam49b-/--mice. Platelet counts and activation of Fam49b-/- mice were comparable to those of control mice. On fully fibrinogen-coated surfaces, Fam49b-/--platelets spread faster with an increased mean projected cell area than control platelets, whereas Cyfip1/Fam49b-/--platelets did not form lamellipodia, phenocopying the Cyfip1-/--platelets. However, Fam49b-/--platelets often assumed a polarized shape and were more prone to migrate on fibrinogen-coated surfaces. On 2D structured micropatterns, however, Fam49b-/--platelets displayed reduced spreading, whereas spreading of Cyfip1-/-- and Cyfip1/Fam49b-/--platelets was enhanced. In summary, FAM49b contributes to the regulation of morphology and migration of spread platelets, but to exert its inhibitory effect on actin polymerization, the functional WAVE complex must be present.


Assuntos
Proteínas de Transporte , Proteínas rac1 de Ligação ao GTP , Animais , Camundongos , Citoesqueleto de Actina/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Plaquetas/metabolismo , Proteínas de Transporte/metabolismo , Fibrinogênio/metabolismo , Mamíferos/metabolismo , Proteínas rac1 de Ligação ao GTP/metabolismo
4.
BMC Infect Dis ; 23(1): 610, 2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37723464

RESUMO

BACKGROUND: The course of monkeypox can be severe. Our aim was to retrospectively compare the risk of hospital admission, the need for ventilation, sepsis, pneumonitis and death between the recent outbreak and historical outbreaks. MATERIALS AND METHODS: Cases of monkeypox were retrieved from the TriNetX database and assigned to either cohort I (recent outbreak between May 1st and September 16th, 2022) and cohort II (historical outbreaks before May 1st, 2022). After matching for age distribution, statistical analysis was performed. RESULTS: Of 640 patients with monkeypox 81 subjects per cohort remained after matching (mean age±standard deviation = 36.1±18.3 years). Within 56 days after diagnosis 10 patients per cohort were hospitalized (12.4%) and/or developed sepsis (12.4%). The risk of ventilation and pneumonitis were significantly lower among cohort I compared with cohort II (0 vs. 10 cases; risk difference = 12.4%; p = 0.001; Log-Rank test). No cases of death were recorded. CONCLUSION: Even though monkeypox provides a risk of severe courses, the infection is self-limiting in most cases. Unlike past outbreaks, the risk of ventilation and pneumonitis may be relatively low among recent outbreaks.


Assuntos
Mpox , Pneumonia , Sepse , Humanos , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Estudos Retrospectivos , Pneumonia/epidemiologia , Sepse/epidemiologia , Surtos de Doenças , Hospitais
5.
Res Pract Thromb Haemost ; 7(4): 100193, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37538494

RESUMO

This year's Congress of the International Society of Thrombosis and Haemostasis (ISTH) took place in person in Montréal, Canada, from June 24-28, 2023. The conference, held annually, highlighted cutting-edge advances in basic, translational, population and clinical sciences relevant to the Society. As for all ISTH congresses, we offered a special, congress-specific scientific theme; this year, the special theme was immunothrombosis. Certainly, over the last few years, COVID-19 infection and its related thrombotic and other complications have renewed interest in the concepts of thromboinflammation and immunothrombosis; namely, the relationship between inflammation, infection and clotting. Other main scientific themes of the Congress included Arterial Thromboembolism, Coagulation and Natural Anticoagulants, Diagnostics and Omics, Fibrinolysis and Proteolysis, Hemophilia and Rare Bleeding Disorders, Hemostatic System in Cancer, Inflammation and Immunity, Pediatrics, Platelet Disorders, von Willebrand Disease and Thrombotic Microangiopathies, Platelets and Megakaryocytes, Vascular Biology, Venous Thromboembolism and Women's Health. Among other sessions, the program included 28 State-of-the-Art (SOA) sessions with a total of 84 talks given by internationally recognized leaders in the field. SOA speakers were invited to prepare brief illustrated reviews of their talks that were peer reviewed and are included in this article. These illustrated capsules highlight the major scientific advances with potential to impact clinical practice. Readers are invited to take advantage of the excellent educational resource provided by these illustrated capsules. They are also encouraged to use the image in social media to draw attention to the high quality and impact of the science presented at the Congress.

6.
J Alzheimers Dis ; 95(3): 1013-1028, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37638433

RESUMO

BACKGROUND: Atrophy of cholinergic basal forebrain (BF) nuclei is a frequent finding in magnetic resonance imaging (MRI) volumetry studies that examined patients with prodromal or clinical Alzheimer's disease (AD), but less clear for individuals in earlier stages of the clinical AD continuum. OBJECTIVE: To examine BF volume reductions in subjective cognitive decline (SCD) participants with AD pathologic changes. METHODS: The present study compared MRI-based BF volume measurements in age- and sex-matched samples of N = 24 amyloid-positive and N = 24 amyloid-negative SCD individuals, based on binary visual ratings of Florbetaben positron emission tomography (PET) measurements. Additionally, we assessed associations of BF volume with cortical amyloid burden, based on semiquantitative Centiloid (CL) analyses. RESULTS: Group differences approached significance for BF total volume (p = 0.061) and the Ch4 subregion (p = 0.059) only, showing the expected relative volume reductions for the amyloid-positive subgroup. There were also significant inverse correlations between BF volumes and CL values, which again were most robust for BF total volume and the Ch4 subregion. CONCLUSIONS: The results are consistent with the hypothesis that amyloid-positive SCD individuals, which are considered to represent a transitional stage on the clinical AD continuum, already show incipient alterations of BF integrity. The negative association with a continuous measure of cortical amyloid burden also suggests that this may reflect an incremental process. Yet, further research is needed to evaluate whether BF changes already emerge at "grey zone" levels of amyloid accumulation, before amyloidosis is reliably detected by PET visual readings.


Assuntos
Doença de Alzheimer , Prosencéfalo Basal , Disfunção Cognitiva , Humanos , Prosencéfalo Basal/diagnóstico por imagem , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/patologia , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/patologia , Amiloide/metabolismo , Imageamento por Ressonância Magnética/métodos , Tomografia por Emissão de Pósitrons , Proteínas Amiloidogênicas , Peptídeos beta-Amiloides/metabolismo
7.
Blood ; 141(24): 2973-2992, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37018659

RESUMO

Platelets are not only the first responders in thrombosis and hemostasis but also central players in inflammation. Compared with platelets recruited to thrombi, immune-responsive platelets use distinct effector functions including actin-related protein complex 2/3-dependent migration along adhesive substrate gradients (haptotaxis), which prevents inflammatory bleeding and contributes to host defense. How platelet migration in this context is regulated on a cellular level is incompletely understood. Here, we use time-resolved morphodynamic profiling of individual platelets to show that migration, in contrast to clot retraction, requires anisotropic myosin IIa-activity at the platelet rear which is preceded by polarized actin polymerization at the front to initiate and maintain migration. Integrin GPIIb-dependent outside-in signaling via Gα13 coordinates polarization of migrating platelets to trigger tyrosine kinase c-Src/14-3-3ζ-dependent lamellipodium formation and functions independent of soluble agonists or chemotactic signals. Inhibitors of this signaling cascade, including the clinically used ABL/c-Src inhibitor dasatinib, interfere predominantly with the migratory capacity of platelets, without major impairment of classical platelet functions. In murine inflammation models, this translates to reduced migration of platelets visualized by 4D intravital microscopy, resulting in increased inflammation-associated hemorrhage in acute lung injury. Finally, platelets isolated from patients with leukemia treated with dasatinib who are prone to clinically relevant hemorrhage exhibit prominent migration defects, whereas other platelet functions are only partially affected. In summary, we define a distinct signaling pathway essential for migration and provide novel mechanistic insights explaining dasatinib-related platelet dysfunction and bleeding.


Assuntos
Plaquetas , Trombose , Humanos , Camundongos , Animais , Plaquetas/metabolismo , Proteínas 14-3-3/metabolismo , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/metabolismo , Glicoproteína IIb da Membrana de Plaquetas/metabolismo , Dasatinibe , Actinas/metabolismo , Trombose/metabolismo , Inflamação/metabolismo
8.
Immunity ; 55(12): 2285-2299.e7, 2022 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-36272416

RESUMO

Intravascular neutrophils and platelets collaborate in maintaining host integrity, but their interaction can also trigger thrombotic complications. We report here that cooperation between neutrophil and platelet lineages extends to the earliest stages of platelet formation by megakaryocytes in the bone marrow. Using intravital microscopy, we show that neutrophils "plucked" intravascular megakaryocyte extensions, termed proplatelets, to control platelet production. Following CXCR4-CXCL12-dependent migration towards perisinusoidal megakaryocytes, plucking neutrophils actively pulled on proplatelets and triggered myosin light chain and extracellular-signal-regulated kinase activation through reactive oxygen species. By these mechanisms, neutrophils accelerate proplatelet growth and facilitate continuous release of platelets in steady state. Following myocardial infarction, plucking neutrophils drove excessive release of young, reticulated platelets and boosted the risk of recurrent ischemia. Ablation of neutrophil plucking normalized thrombopoiesis and reduced recurrent thrombosis after myocardial infarction and thrombus burden in venous thrombosis. We establish neutrophil plucking as a target to reduce thromboischemic events.


Assuntos
Doenças Cardiovasculares , Infarto do Miocárdio , Trombose , Humanos , Megacariócitos , Trombopoese , Neutrófilos , Plaquetas/fisiologia
10.
Blood ; 140(2): 121-139, 2022 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-35472164

RESUMO

Impairment of vascular integrity is a hallmark of inflammatory diseases. We recently reported that single immune-responsive platelets migrate and reposition themselves to sites of vascular injury to prevent bleeding. However, it remains unclear how single platelets preserve vascular integrity once encountering endothelial breaches. Here we demonstrate by intravital microscopy combined with genetic mouse models that procoagulant activation (PA) of single platelets and subsequent recruitment of the coagulation cascade are crucial for the prevention of inflammatory bleeding. Using a novel lactadherin-based compound, we detect phosphatidylserine (PS)-positive procoagulant platelets in the inflamed vasculature. We identify exposed collagen as the central trigger arresting platelets and initiating subsequent PA in a CypD- and TMEM16F-dependent manner both in vivo and in vitro. Platelet PA promotes binding of the prothrombinase complex to the platelet membrane, greatly enhancing thrombin activity and resulting in fibrin formation. PA of migrating platelets is initiated by costimulation via integrin αIIbß3 (GPIIBIIIA)/Gα13-mediated outside-in signaling and glycoprotein VI signaling, leading to an above-threshold intracellular calcium release. This effectively targets the coagulation cascade to breaches of vascular integrity identified by patrolling platelets. Platelet-specific genetic loss of either CypD or TMEM16F as well as combined blockade of platelet GPIIBIIIA and glycoprotein VI reduce platelet PA in vivo and aggravate pulmonary inflammatory hemorrhage. Our findings illustrate a novel role of procoagulant platelets in the prevention of inflammatory bleeding and provide evidence that PA of patrolling platelet sentinels effectively targets and confines activation of coagulation to breaches of vascular integrity.


Assuntos
Plaquetas , Glicoproteínas da Membrana de Plaquetas , Animais , Plaquetas/metabolismo , Hemorragia/metabolismo , Camundongos , Ativação Plaquetária , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/metabolismo , Glicoproteínas da Membrana de Plaquetas/metabolismo
11.
Haematologica ; 107(7): 1669-1680, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34525794

RESUMO

Visualizing cell behavior and effector function on a single cell level has been crucial for understanding key aspects of mammalian biology. Due to their small size, large number and rapid recruitment into thrombi, there is a lack of data on fate and behavior of individual platelets in thrombosis and hemostasis. Here we report the use of platelet lineage restricted multi-color reporter mouse strains to delineate platelet function on a single cell level. We show that genetic labeling allows for single platelet and megakaryocyte (MK) tracking and morphological analysis in vivo and in vitro, while not affecting lineage functions. Using Cre-driven Confetti expression, we provide insights into temporal gene expression patterns as well as spatial clustering of MK in the bone marrow. In the vasculature, shape analysis of activated platelets recruited to thrombi identifies ubiquitous filopodia formation with no evidence of lamellipodia formation. Single cell tracking in complex thrombi reveals prominent myosin-dependent motility of platelets and highlights thrombus formation as a highly dynamic process amenable to modification and intervention of the acto-myosin cytoskeleton. Platelet function assays combining flow cytrometry, as well as in vivo, ex vivo and in vitro imaging show unaltered platelet functions of multicolor reporter mice compared to wild-type controls. In conclusion, platelet lineage multicolor reporter mice prove useful in furthering our understanding of platelet and MK biology on a single cell level.


Assuntos
Megacariócitos , Trombose , Animais , Plaquetas/metabolismo , Medula Óssea/metabolismo , Hemostasia , Mamíferos , Megacariócitos/metabolismo , Camundongos , Trombose/metabolismo
12.
Dev Cell ; 57(1): 47-62.e9, 2022 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-34919802

RESUMO

When crawling through the body, leukocytes often traverse tissues that are densely packed with extracellular matrix and other cells, and this raises the question: How do leukocytes overcome compressive mechanical loads? Here, we show that the actin cortex of leukocytes is mechanoresponsive and that this responsiveness requires neither force sensing via the nucleus nor adhesive interactions with a substrate. Upon global compression of the cell body as well as local indentation of the plasma membrane, Wiskott-Aldrich syndrome protein (WASp) assembles into dot-like structures, providing activation platforms for Arp2/3 nucleated actin patches. These patches locally push against the external load, which can be obstructing collagen fibers or other cells, and thereby create space to facilitate forward locomotion. We show in vitro and in vivo that this WASp function is rate limiting for ameboid leukocyte migration in dense but not in loose environments and is required for trafficking through diverse tissues such as skin and lymph nodes.


Assuntos
Actinas/fisiologia , Leucócitos/fisiologia , Proteína da Síndrome de Wiskott-Aldrich/metabolismo , Complexo 2-3 de Proteínas Relacionadas à Actina/metabolismo , Complexo 2-3 de Proteínas Relacionadas à Actina/fisiologia , Proteína 3 Relacionada a Actina/metabolismo , Actinas/metabolismo , Animais , Fenômenos Biomecânicos/fisiologia , Linhagem Celular , Movimento Celular/fisiologia , Proteínas do Citoesqueleto/metabolismo , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Ligação Proteica/fisiologia , Proteína da Síndrome de Wiskott-Aldrich/genética
13.
Medicine (Baltimore) ; 100(38): e27082, 2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34559100

RESUMO

RATIONALE: Recurrence of hepatocellular carcinoma (HCC) after liver transplantation (LT) remains a major therapeutic challenge. In recent years, new molecular-targeted therapies, such as cabozantinib, have been approved for the treatment of advanced HCC. However, clinical experience with these new drugs in the treatment of HCC in the LT setting is very limited. PATIENT CONCERNS: In 2003, a 36-year-old woman was referred to the hospital with right upper abdominal pain. DIAGNOSIS: An initial ultrasound of the liver demonstrated a large unclear lesion of the left lobe of the liver. The magnet resonance imaging findings confirmed a multifocal inoperable HCC in a non-cirrhotic liver. Seven years after receiving a living donor LT, pulmonary and intra-hepatic recurrence of the HCC was radiologically diagnosed and histologically confirmed. INTERVENTIONS: Following an interdisciplinary therapy concept consisting of surgical, interventional-radiological (with radiofrequency ablation [RFA]) as well as systemic treatment, the patient achieved a survival of more than 10 years after tumor recurrence. As systemic first line therapy with sorafenib was accompanied by grade 3 to 4 toxicities, such as mucositis, hand-foot skin reaction, diarrhea, liver dysfunction, and hyperthyroidism, it had to be discontinued. After switching to cabozantinib from June 2018 to April 2020, partial remission of all tumor manifestations was achieved. The treatment of the remaining liver metastasis could be completed by RFA. The therapy with cabozantinib was well tolerated, only mild arterial hypertension and grade 1 to 2 mucositis were observed. Liver transplant function was stable during the therapy, no drug interaction with immunosuppressive drugs was observed. OUTCOMES: More than 10 years survival after recurrence of HCC after living-donor LT due to intensive multimodal therapy concepts, including surgery, RFA, and systemic therapy with cabozantinib in the second line therapy. LESSONS: In conclusion, this report highlights the tolerability and effectiveness of cabozantinib for the treatment of HCC recurrence after LT. We show that our patient with a late recurrence of HCC after LT benefitted from intensive multimodal therapy concepts, including surgery, RFA, and systemic therapy.


Assuntos
Carcinoma Hepatocelular/diagnóstico , Neoplasias Hepáticas/diagnóstico , Transplante de Fígado , Dor Abdominal/etiologia , Adulto , Anilidas/administração & dosagem , Anilidas/uso terapêutico , Carcinoma Hepatocelular/secundário , Carcinoma Hepatocelular/terapia , Terapia Combinada , Diagnóstico Diferencial , Feminino , Seguimentos , Humanos , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/terapia , Terapia de Alvo Molecular , Metástase Neoplásica , Recidiva Local de Neoplasia , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/terapia , Piridinas/administração & dosagem , Piridinas/uso terapêutico , Ablação por Radiofrequência
14.
Nuklearmedizin ; 60(5): 344-354, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34256394

RESUMO

AIM: Gallium-68-labelled inhibitors of the fibroblast activation protein (FAPi) enable positron emission tomography/computed tomography (PET/CT) imaging of fibroblast activation. We evaluated if [68Ga]Ga-DATA5m.SA.FAPi PET/CT is related to Ki-67 as a marker of tumour aggressiveness in patients with liver metastases of NET. METHODS: Thirteen patients with liver metastases of a histologically confirmed NET who underwent PET/CT with [68Ga]Ga-DATA5m.SA.FAPi, [18F]FDG and [68Ga]Ga-DOTA-TOC were retrospectively analyzed. PET-positive liver tumour volumes were segmented for calculation of volume, SUVmax and PET-positive tumour fraction (TF). PET parameters were correlated with Ki-67. RESULTS: FDGSUVmax correlated positively (rho = 0.543, p < 0.05) and DOTATOCSUVmax correlated negatively (rho = -0.618, p < 0.05) with Ki-67, the correlation coefficients were in the moderate range. There was no significant correlation between FAPiSUVmax and Ki-67 (rho = 0.382, p > 0.05). FAPiTF correlated positively (rho = 0.770, p < 0.01) and DOTATOCTF correlated negatively (rho = -0.828, p < 0.01) with Ki-67, both significantly with high correlation coefficients. FDGTF also correlated significantly with Ki-67, with a moderate correlation coefficient (rho = 0.524, p < 0.05). The ratio FAPiVOL:DOTATOCVOL showed a significant and strong correlation with Ki-67 (rho = 0.808, p < 0.01). CONCLUSION: The ratio FAPiVOL:DOTATOCVOL might serve as a clinical parameter for the assessment of dedifferentiation and aggressiveness of liver metastases in patients with NET. [68Ga]Ga-DATA5m.SA.FAPi might hold potential for identification of high-risk patients. Further studies are warranted to evaluate its prognostic significance in comparison to [18F]FDG in patients with NET.


Assuntos
Neoplasias Hepáticas , Tumores Neuroendócrinos , Fibroblastos , Humanos , Antígeno Ki-67 , Neoplasias Hepáticas/diagnóstico por imagem , Tumores Neuroendócrinos/diagnóstico por imagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Estudos Retrospectivos
15.
Dev Cell ; 56(6): 723-725, 2021 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-33756118

RESUMO

In this issue of Developmental Cell, Doyle and colleagues identify periodic anterior contraction as a characteristic feature of fibroblasts and mesenchymal cancer cells embedded in 3D collagen gels. This contractile mechanism generates a matrix prestrain required for crawling in fibrous 3D environments.


Assuntos
Colágeno , Fibroblastos , Géis , Humanos
16.
Diagnostics (Basel) ; 11(2)2021 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-33525456

RESUMO

Prostate-specific membrane antigen (PSMA) positron emission tomography/computed tomography (PSMA-PET/CT) scans can facilitate diagnosis and treatment of prostate disease. Radiomics signature (RS) is widely used for the analysis of overall survival (OS) in cancer diseases. This study aims at investigating the role of radiomics features (RFs) and RS from pretherapeutic gallium-68 (68Ga)-PSMA-PET/CT findings and patient-specific clinical parameters to analyze overall survival of prostate cancer (PC) patients when treated with lutethium-177 (177Lu)-PSMA. A cohort of 83 patients with advanced PC was retrospectively analyzed. Average values of 73 RFs of 2070 malignant hotspots as well as 22 clinical parameters were analyzed for each patient. From the Cox proportional hazard model, the least absolute shrinkage and selection operator (LASSO) regularization method is used to select most relevant features (standardized uptake value (SUV)Min and kurtosis with the coefficients of 0.984 and -0.118, respectively) and to calculate the RS from the RFs. Kaplan-Meier (KM) estimator was used to analyze the potential of RFs and conventional clinical parameters, such as metabolic tumor volume (MTV) and standardized uptake value (SUV) for the prediction of survival. As a result, SUVMin, kurtosis, the calculated RS, SUVMean, as well as Hemoglobin (Hb)1, C-reactive protein (CRP)1, and ECOG1 (clinical parameters) achieved p-values less than 0.05, which suggest the potential of findings from 68Ga-PSMA-PET/CT scans as well as patient-specific clinical parameters for the prediction of OS for patients with advanced PC treated with 177Lu-PSMA therapy.

17.
J Alzheimers Dis ; 79(2): 493-509, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33337359

RESUMO

BACKGROUND: Amyloid-ß accumulation was found to alter precuneus-based functional connectivity (FC) in mild cognitive impairment (MCI) and Alzheimer's disease (AD) dementia, but its impact is less clear in subjective cognitive decline (SCD), which in combination with AD pathologic change is theorized to correspond to stage 2 of the Alzheimer's continuum in the 2018 NIA-AA research framework. OBJECTIVE: This study addresses how amyloid pathology relates to resting-state fMRI FC in SCD, especially focusing on the precuneus. METHODS: From the DELCODE cohort, two groups of 24 age- and gender-matched amyloid-positive (SCDAß+) and amyloidnegative SCD (SCDß-) patients were selected according to visual [18F]-Florbetaben (FBB) PET readings, and studied with resting-state fMRI. Local (regional homogeneity [ReHo], fractional amplitude of low-frequency fluctuations [fALFF]) and global (degree centrality [DC], precuneus seed-based FC) measures were compared between groups. Follow-up correlation analyses probed relationships of group differences with global and precuneal amyloid load, as measured by FBB standard uptake value ratios (SUVR=⫖FBB). RESULTS: ReHo was significantly higher (voxel-wise p < 0.01, cluster-level p < 0.05) in the bilateral precuneus for SCDAß+patients, whereas fALFF was not altered between groups. Relatively higher precuneus-based FC with occipital areas (but no altered DC) was observed in SCDAß+ patients. In this latter cluster, precuneus-occipital FC correlated positively with global (SCDAß+) and precuneus SUVRFBB (both groups). CONCLUSION: While partial confounding influences due to a higher APOE ε4 carrier ratio among SCDAß+ patients cannot be excluded, exploratory results indicate functional alterations in the precuneus hub region that were related to amyloid-ß load, highlighting incipient pathology in stage 2 of the AD continuum.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Disfunção Cognitiva/diagnóstico por imagem , Imageamento por Ressonância Magnética , Idoso , Compostos de Anilina , Estudos de Coortes , Feminino , Humanos , Masculino , Lobo Parietal/patologia , Estilbenos
18.
Nat Commun ; 11(1): 5778, 2020 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-33188196

RESUMO

Breakdown of vascular barriers is a major complication of inflammatory diseases. Anucleate platelets form blood-clots during thrombosis, but also play a crucial role in inflammation. While spatio-temporal dynamics of clot formation are well characterized, the cell-biological mechanisms of platelet recruitment to inflammatory micro-environments remain incompletely understood. Here we identify Arp2/3-dependent lamellipodia formation as a prominent morphological feature of immune-responsive platelets. Platelets use lamellipodia to scan for fibrin(ogen) deposited on the inflamed vasculature and to directionally spread, to polarize and to govern haptotactic migration along gradients of the adhesive ligand. Platelet-specific abrogation of Arp2/3 interferes with haptotactic repositioning of platelets to microlesions, thus impairing vascular sealing and provoking inflammatory microbleeding. During infection, haptotaxis promotes capture of bacteria and prevents hematogenic dissemination, rendering platelets gate-keepers of the inflamed microvasculature. Consequently, these findings identify haptotaxis as a key effector function of immune-responsive platelets.


Assuntos
Plaquetas/patologia , Vasos Sanguíneos/patologia , Quimiotaxia , Inflamação/patologia , Pneumonia/sangue , Complexo 2-3 de Proteínas Relacionadas à Actina/metabolismo , Adulto , Animais , Movimento Celular , Microambiente Celular , Modelos Animais de Doenças , Fibrinogênio/metabolismo , Humanos , Lipopolissacarídeos , Lesão Pulmonar/microbiologia , Lesão Pulmonar/patologia , Staphylococcus aureus Resistente à Meticilina/fisiologia , Camundongos Endogâmicos C57BL , Microvasos/patologia , Pneumonia/microbiologia , Pseudópodes/metabolismo
19.
Nature ; 582(7813): 582-585, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32581372

RESUMO

Eukaryotic cells migrate by coupling the intracellular force of the actin cytoskeleton to the environment. While force coupling is usually mediated by transmembrane adhesion receptors, especially those of the integrin family, amoeboid cells such as leukocytes can migrate extremely fast despite very low adhesive forces1. Here we show that leukocytes cannot only migrate under low adhesion but can also transmit forces in the complete absence of transmembrane force coupling. When confined within three-dimensional environments, they use the topographical features of the substrate to propel themselves. Here the retrograde flow of the actin cytoskeleton follows the texture of the substrate, creating retrograde shear forces that are sufficient to drive the cell body forwards. Notably, adhesion-dependent and adhesion-independent migration are not mutually exclusive, but rather are variants of the same principle of coupling retrograde actin flow to the environment and thus can potentially operate interchangeably and simultaneously. As adhesion-free migration is independent of the chemical composition of the environment, it renders cells completely autonomous in their locomotive behaviour.


Assuntos
Citoesqueleto de Actina/metabolismo , Movimento Celular , Microambiente Celular , Linfócitos T/citologia , Actinas/metabolismo , Animais , Adesão Celular , Linhagem Celular , Humanos , Camundongos , Linfócitos T/metabolismo , Talina/deficiência
20.
Nuklearmedizin ; 59(5): 375-380, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32422668

RESUMO

Sialoscintigraphy has been used in nuclear imaging for almost sixty years. It allows functional assessment and quantification of all large salivary glands. Physiological function of the salivary glands is essential for the preservation of the oral mucosa, the sense of taste and dental health. Impaired salivary gland function may lead to reduced or even absent salivation resulting in various complaints such as loss of taste reducing quality of life. During the recent years clinical relevance of assessment of salivary gland function has been rising. As novel radiopharmaceuticals such as 225Ac-PSMA or 177Lu-PSMA may cause damage to the salivary glands in a subset of patients, reliable methods for quantification of salivary gland function are vital for therapy planning and follow-up. Standardized protocols for the implementation and interpretation of this procedure are necessary to achieve comparable results from individual theranostic centers and to facilitate multicenter trials. Sialocintigraphy is also of clinical relevance for immunooncology. Treatments with checkpoint inhibitors such as Ipilimumab or Nivulomab frequently cause autoimmune disorders affecting the salivary glands that may lead to reduced production of saliva and finally loss of taste. Therefore, standardized procedure protocols for sialoscintigraphy are also important for general oncology.Here we suggest a protocol for sialoscintigraphy that may be used as standard in centers for theranostics or immunooncology and discuss the potential future role of this traditional procedure.


Assuntos
Neoplasias/diagnóstico por imagem , Neoplasias/imunologia , Cintilografia , Glândulas Salivares/diagnóstico por imagem , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/terapia , Qualidade de Vida
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