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1.
Redox Biol ; 67: 102909, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37801856

RESUMO

Few therapies have produced significant improvement in cardiac structure and function after ischemic cardiac injury (ICI). Our possible explanation is activation of local inflammatory responses negatively impact the cardiac repair process following ischemic injury. Factors that can alter immune response, including significantly altered cytokine levels in plasma and polarization of macrophages and T cells towards a pro-reparative phenotype in the myocardium post-MI is a valid strategy for reducing infarct size and damage after myocardial injury. Our previous studies showed that cortical bone stem cells (CBSCs) possess reparative effects after ICI. In our current study, we have identified that the beneficial effects of CBSCs appear to be mediated by miRNA in their extracellular vesicles (CBSC-EV). Our studies showed that CBSC-EV treated animals demonstrated reduced scar size, attenuated structural remodeling, and improved cardiac function versus saline treated animals. These effects were linked to the alteration of immune response, with significantly altered cytokine levels in plasma, and polarization of macrophages and T cells towards a pro-reparative phenotype in the myocardium post-MI. Our detailed in vitro studies demonstrated that CBSC-EV are enriched in miR-182/183 that mediates the pro-reparative polarization and metabolic reprogramming in macrophages, including enhanced OXPHOS rate and reduced ROS, via Ras p21 protein activator 1 (RASA1) axis under Lipopolysaccharides (LPS) stimulation. In summary, CBSC-EV deliver unique molecular cargoes, such as enriched miR-182/183, that modulate the immune response after ICI by regulating macrophage polarization and metabolic reprogramming to enhance repair.


Assuntos
Traumatismos Cardíacos , MicroRNAs , Infarto do Miocárdio , Animais , Camundongos , Miocárdio/metabolismo , Infarto do Miocárdio/genética , Macrófagos/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Citocinas/metabolismo , Proteínas Ativadoras de GTPase/metabolismo , Oxirredução , Camundongos Endogâmicos C57BL
2.
J Clin Med ; 12(5)2023 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-36902631

RESUMO

(1) Background: The treatment of proximal humeral fractures (PHFs) is debated controversially. Current clinical knowledge is mainly based on small single-center cohorts. The goal of this study was to evaluate the predictability of risk factors for complications after the treatment of a PHF in a large clinical cohort in a multicentric setting. (2) Methods: Clinical data of 4019 patients with PHFs were retrospectively collected from 9 participating hospitals. Risk factors for local complications of the affected shoulder were assessed using bi- and multivariate analyses. (3) Results: Fracture complexity with n = 3 or more fragments, cigarette smoking, age over 65 years, and female sex were identified as predictable individual risk factors for local complications after surgical therapy as well as the combination of female sex and smoking and the combination of age 65 years or older and ASA class 2 or higher. (4) Conclusion: Humeral head preserving reconstructive surgical therapy should critically be evaluated for patients with the risk factors abovementioned.

3.
Int J Mol Sci ; 22(15)2021 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-34360579

RESUMO

Ischemic heart disease can lead to myocardial infarction (MI), a major cause of morbidity and mortality worldwide. Multiple stem cell types have been safely transferred into failing human hearts, but the overall clinical cardiovascular benefits have been modest. Therefore, there is a dire need to understand the basic biology of stem cells to enhance therapeutic effects. Bmi1 is part of the polycomb repressive complex 1 (PRC1) that is involved in different processes including proliferation, survival and differentiation of stem cells. We isolated cortical bones stem cells (CBSCs) from bone stroma, and they express significantly high levels of Bmi1 compared to mesenchymal stem cells (MSCs) and cardiac-derived stem cells (CDCs). Using lentiviral transduction, Bmi1 was knocked down in the CBSCs to determine the effect of loss of Bmi1 on proliferation and survival potential with or without Bmi1 in CBSCs. Our data show that with the loss of Bmi1, there is a decrease in CBSC ability to proliferate and survive during stress. This loss of functionality is attributed to changes in histone modification, specifically histone 3 lysine 27 (H3K27). Without the proper epigenetic regulation, due to the loss of the polycomb protein in CBSCs, there is a significant decrease in cell cycle proteins, including Cyclin B, E2F, and WEE as well as an increase in DNA damage genes, including ataxia-telangiectasia mutated (ATM) and ATM and Rad3-related (ATR). In conclusion, in the absence of Bmi1, CBSCs lose their proliferative potential, have increased DNA damage and apoptosis, and more cell cycle arrest due to changes in epigenetic modifications. Consequently, Bmi1 plays a critical role in stem cell proliferation and survival through cell cycle regulation, specifically in the CBSCs. This regulation is associated with the histone modification and regulation of Bmi1, therefore indicating a novel mechanism of Bmi1 and the epigenetic regulation of stem cells.


Assuntos
Apoptose , Proliferação de Células , Osso Cortical/citologia , Epigênese Genética , Histonas/metabolismo , Complexo Repressor Polycomb 1/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Células-Tronco/citologia , Animais , Ciclo Celular , Diferenciação Celular , Células Cultivadas , Osso Cortical/lesões , Osso Cortical/metabolismo , Dano ao DNA , Histonas/genética , Camundongos , Camundongos Endogâmicos C57BL , Complexo Repressor Polycomb 1/genética , Proteínas Proto-Oncogênicas/genética , Transdução de Sinais , Células-Tronco/metabolismo
4.
Front Immunol ; 11: 639, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32328072

RESUMO

Cardiovascular Disease (CVD) is a leading cause of mortality within the United States. Current treatments being administered to patients who suffered a myocardial infarction (MI) have increased patient survival, but do not facilitate the replacement of damaged myocardium. Recent studies demonstrate that stem cell-based therapies promote myocardial repair; however, the poor engraftment of the transferred stem cell populations within the infarcted myocardium is a major limitation, regardless of the cell type. One explanation for poor cell retention is attributed to the harsh inflammatory response mounted following MI. The inflammatory response coupled to cardiac repair processes is divided into two distinct phases. The first phase is initiated during ischemic injury when necrosed myocardium releases Danger Associated Molecular Patterns (DAMPs) and chemokines/cytokines to induce the activation and recruitment of neutrophils and pro-inflammatory M1 macrophages (MΦs); in turn, facilitating necrotic tissue clearance. During the second phase, a shift from the M1 inflammatory functional phenotype to the M2 anti-inflammatory and pro-reparative functional phenotype, permits the resolution of inflammation and the establishment of tissue repair. T-regulatory cells (Tregs) are also influential in mediating the establishment of the pro-reparative phase by directly regulating M1 to M2 MΦ differentiation. Current studies suggest CD4+ T-lymphocyte populations become activated when presented with autoantigens released from the injured myocardium. The identity of the cardiac autoantigens or paracrine signaling molecules released from the ischemic tissue that directly mediate the phenotypic plasticity of T-lymphocyte populations in the post-MI heart are just beginning to be elucidated. Stem cells are enriched centers that contain a diverse paracrine secretome that can directly regulate responses within neighboring cell populations. Previous studies identify that stem cell mediated paracrine signaling can influence the phenotype and function of immune cell populations in vitro, but how stem cells directly mediate the inflammatory microenvironment of the ischemic heart is poorly characterized and is a topic of extensive investigation. In this review, we summarize the complex literature that details the inflammatory microenvironment of the ischemic heart and provide novel insights regarding how paracrine mediated signaling produced by stem cell-based therapies can regulate immune cell subsets to facilitate pro-reparative myocardial wound healing.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Doenças Cardiovasculares/terapia , Inflamação/imunologia , Macrófagos/imunologia , Transplante de Células-Tronco , Autoimunidade , Doenças Cardiovasculares/imunologia , Microambiente Celular , Imunomodulação , Equilíbrio Th1-Th2 , Cicatrização
5.
Gigascience ; 9(3)2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-32161948

RESUMO

BACKGROUND: We present an image dataset related to automated segmentation and counting of macrophages in diffuse large B-cell lymphoma (DLBCL) tissue sections. For the classification of DLBCL subtypes, as well as for providing a prognosis of the clinical outcome, the analysis of the tumor microenvironment and, particularly, of the different types and functions of tumor-associated macrophages is indispensable. Until now, however, most information about macrophages has been obtained either in a completely indirect way by gene expression profiling or by manual counts in immunohistochemically (IHC) fluorescence-stained tissue samples while automated recognition of single IHC stained macrophages remains a difficult task. In an accompanying publication, a reliable approach to this problem has been established, and a large set of related images has been generated and analyzed. RESULTS: Provided image data comprise (i) fluorescence microscopy images of 44 multiple immunohistostained DLBCL tumor subregions, captured at 4 channels corresponding to CD14, CD163, Pax5, and DAPI; (ii) "cartoon-like" total variation-filtered versions of these images, generated by Rudin-Osher-Fatemi denoising; (iii) an automatically generated mask of the evaluation subregion, based on information from the DAPI channel; and (iv) automatically generated segmentation masks for macrophages (using information from CD14 and CD163 channels), B-cells (using information from Pax5 channel), and all cell nuclei (using information from DAPI channel). CONCLUSIONS: A large set of IHC stained DLBCL specimens is provided together with segmentation masks for different cell populations generated by a reference method for automated image analysis, thus featuring considerable reuse potential.


Assuntos
Imunofluorescência/métodos , Interpretação de Imagem Assistida por Computador/métodos , Linfoma Difuso de Grandes Células B/patologia , Macrófagos/patologia , Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/metabolismo , Conjuntos de Dados como Assunto , Imunofluorescência/normas , Interpretação de Imagem Assistida por Computador/normas , Receptores de Lipopolissacarídeos/metabolismo , Linfoma Difuso de Grandes Células B/classificação , Macrófagos/metabolismo , Fator de Transcrição PAX5/metabolismo , Receptores de Superfície Celular/metabolismo
6.
Int J Numer Method Biomed Eng ; 35(11): e3249, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31400057

RESUMO

Finite element (FE)-based studies of preoperative processes such as folding, pleating, and stent crimping with a comparison with experimental inflation tests are not yet available. Therefore, a novel workflow is presented in which residual stresses of balloon folding and pleating, as well as stent crimping, and the geometries of all contact partners were ultimately implemented in an FE code to simulate stent expansion by using an implicit solver. The numerical results demonstrate that the incorporation of residual stresses and strains experienced during the production step significantly increased the accuracy of the subsequent simulations, especially of the stent expansion model. During the preoperative processes, stresses inside the membrane and the stent material also reached a rather high level. Hence, there can be no presumption that balloon catheters or stents are undamaged before the actual surgery. The implementation of the realistic geometry, in particular the balloon tapers, and the blades of the process devices improved the simulation of the expansion mechanisms, such as dogboning, concave bending, or overexpansion of stent cells. This study shows that implicit solvers are able to precisely simulate the mentioned preoperative processes and the stent expansion procedure without a preceding manipulation of the simulation time or physical mass.


Assuntos
Stents , Cateterismo/métodos , Módulo de Elasticidade , Análise de Elementos Finitos , Desenho de Prótese , Resistência à Tração , Microtomografia por Raio-X
7.
Biol Proced Online ; 21: 13, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31303867

RESUMO

BACKGROUND: For analysis of the tumor microenvironment in diffuse large B-cell lymphoma (DLBCL) tissue samples, it is desirable to obtain information about counts and distribution of different macrophage subtypes. Until now, macrophage counts are mostly inferred from gene expression analysis of whole tissue sections, providing only indirect information. Direct analysis of immunohistochemically (IHC) fluorescence stained tissue samples is confronted with several difficulties, e.g. high variability of shape and size of target macrophages and strongly inhomogeneous intensity of staining. Consequently, application of commercial software is largely restricted to very rough analysis modes, and most macrophage counts are still obtained by manual counting in microarrays or high power fields, thus failing to represent the heterogeneity of tumor microenvironment adequately. METHODS: We describe a Rudin-Osher-Fatemi (ROF) filter based segmentation approach for whole tissue samples, combining floating intensity thresholding and rule-based feature detection. Method is validated against manual counts and compared with two commercial software kits (Tissue Studio 64, Definiens AG, and Halo, Indica Labs) and a straightforward machine-learning approach in a set of 50 test images. Further, the novel method and both commercial packages are applied to a set of 44 whole tissue sections. Outputs are compared with gene expression data available for the same tissue samples. Finally, the ROF based method is applied to 44 expert-specified tumor subregions for testing selection and subsampling strategies. RESULTS: Among all tested methods, the novel approach is best correlated with manual count (0.9297). Automated detection of evaluation subregions proved to be fully reliable. Comparison with gene expression data obtained for the same tissue samples reveals only moderate to low correlation levels. Subsampling within tumor subregions is possible with results almost identical to full sampling. Mean macrophage size in tumor subregions is 152.5±111.3 µm2. CONCLUSIONS: ROF based approach is successfully applied to detection of IHC stained macrophages in DLBCL tissue samples. The method competes well with existing commercial software kits. In difference to them, it is fully automated, externally repeatable, independent on training data and completely documented. Comparison with gene expression data indicates that image morphometry constitutes an independent source of information about antibody-polarized macrophage occurence and distribution.

8.
Radiat Oncol ; 7: 219, 2012 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-23256610

RESUMO

BACKGROUND: The utility of definitive radiotherapy (RT) for locoregionally advanced squamous cell carcinoma (SCC) of the larynx or hypopharynx in the setting of thyroid or cricoid cartilage invasion (TCCI) is controversial. A retrospective review of our experience was performed. METHODS: Our institutional database of patients with SCC of the head and neck treated with radiotherapy (90% received concurrent systemic therapy) between 1995 and 2009 was queried. We identified 87 patients with T3-4 laryngeal or T4 hypopharyngeal cancer for whom initial head and neck imaging was available for review. Imaging of all patients was reviewed by a single radiologist specializing in neuroradiology. The presence and extent of TCCI was determined and used for stratification. RESULTS: Median follow-up was 34 months. TCCI was found in 25 (29%) patients, eight limited to the inner cortex and another 17 involving both cortices. Local control (LC) was not significantly affected by TCCI limited to the inner cortex. However, TCCI involving both cortices was correlated with diminished LC at 2 years compared to the group of patients with no or minor invasion (55% vs. 81%, p=0.045). However, TCCI involving both cortices was not associated with significantly reduced rates of survival with a functional larynx, or overall survival (OS). CONCLUSIONS: Our results suggest that the rate of LC of T3-4 laryngeal or T4 hypopharyngeal SCC treated with definitive RT is not affected by TCCI of the inner cortex. Although decreased LC was significantly associated with TCCI involving both cortices, this factor did not appear to result in reduced rates of survival with a functional larynx or OS. Therefore, organ preservation may remain an option in these patients.


Assuntos
Carcinoma de Células Escamosas/patologia , Cartilagem Cricoide/patologia , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias Hipofaríngeas/patologia , Neoplasias Laríngeas/patologia , Cartilagem Tireóidea/patologia , Neoplasias da Glândula Tireoide/secundário , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/radioterapia , Bases de Dados Factuais , Feminino , Neoplasias de Cabeça e Pescoço/mortalidade , Neoplasias de Cabeça e Pescoço/radioterapia , Humanos , Neoplasias Hipofaríngeas/mortalidade , Neoplasias Hipofaríngeas/radioterapia , Neoplasias Laríngeas/mortalidade , Neoplasias Laríngeas/radioterapia , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Carcinoma de Células Escamosas de Cabeça e Pescoço , Neoplasias da Glândula Tireoide/mortalidade , Tomografia Computadorizada por Raios X/métodos , Resultado do Tratamento
9.
Int J Radiat Oncol Biol Phys ; 71(5): 1322-8, 2008 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-18472365

RESUMO

PURPOSE: To determine the target coverage for proton therapy with and without image guidance and daily prebeam reorientation. METHODS AND MATERIALS: A total of 207 prostate positions were analyzed for 9 prostate cancer patients treated using our low-risk prostate proton therapy protocol (University of Florida Proton Therapy Institute 001). The planning target volume was defined as the prostate plus a 5-mm axial and 8-mm superoinferior extension. The prostate was repositioned using 5- and 10-mm shifts (anteriorly, inferiorly, posteriorly, and superiorly) and for Points A-D using a combination of 10-mm multidimensional movements (anteriorly or inferiorly; posteriorly or superiorly; and left or right). The beams were then realigned using the new prostate position. The prescription dose was 78 Gray equivalent (GE) to 95% of the planning target volume. RESULTS: For small movements in the anterior, inferior, and posterior directions within the planning target volume (< or =5 mm), treatment realignment demonstrated small, but significant, improvements in the clinical target volume (CTV) coverage to the prescribed dose (78 GE). The anterior and posterior shifts also significantly increased the minimal CTV dose (Delta +1.59 GE). For prostate 10-mm movements in the inferior, posterior, and superior directions, the beam realignment produced larger and significant improvements for both the CTV V(78) (Delta +6.4%) and the CTV minimal dose (Delta +8.22 GE). For the compounded 10-mm multidimensional shifts, realignment significantly improved the CTV V(78) (Delta +11.8%) and CTV minimal dose (Delta +23.6 GE). After realignment, the CTV minimal dose was >76.6 GE (>98%) for all points (A-D). CONCLUSION: Proton beam realignment after target shift will enhance CTV coverage for different prostate positions.


Assuntos
Movimento , Próstata , Neoplasias da Próstata/radioterapia , Terapia com Prótons , Planejamento da Radioterapia Assistida por Computador , Estudos de Viabilidade , Humanos , Masculino , Próstata/patologia , Neoplasias da Próstata/patologia , Dosagem Radioterapêutica , Carga Tumoral
10.
Int J Radiat Oncol Biol Phys ; 70(5): 1492-501, 2008 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-18374228

RESUMO

PURPOSE: To determine the impact of prostate motion on dose coverage in proton therapy. METHODS AND MATERIALS: A total of 120 prostate positions were analyzed on 10 treatment plans for 10 prostate patients treated using our low-risk proton therapy prostate protocol (University of Florida Proton Therapy Institute 001). Computed tomography and magnetic resonance imaging T(2)-weighted turbo spin-echo scans were registered for all cases. The planning target volume included the prostate with a 5-mm axial and 8-mm superoinferior expansion. The prostate was repositioned using 5- and 10-mm one-dimensional vectors and 10-mm multidimensional vectors (Points A-D). The beam was realigned for the 5- and 10-mm displacements. The prescription dose was 78 Gy equivalent (GE). RESULTS: The mean percentage of rectum receiving 70 Gy (V(70)) was 7.9%, the bladder V(70) was 14.0%, and the femoral head/neck V(50) was 0.1%, and the mean pelvic dose was 4.6 GE. The percentage of prostate receiving 78 Gy (V(78)) with the 5-mm movements changed by -0.2% (range, 0.006-0.5%, p > 0.7). However, the prostate V(78) after a 10-mm displacement changed significantly (p < 0.003) with different movements: 3.4% (superior), -5.6% (inferior), and -10.2% (posterior). The corresponding minimal doses were also reduced: 4.5 GE, -4.7 GE, and -11.7 GE (p < or = 0.003). For displacement points A-D, the clinical target volume V(78) coverage had a large and significant reduction of 17.4% (range, 13.5-17.4%, p < 0.001) in V(78) coverage of the clinical target volume. The minimal prostate dose was reduced 33% (25.8 GE), on average, for Points A-D. The prostate minimal dose improved from 69.3 GE to 78.2 GE (p < 0.001) with realignment for 10-mm movements. CONCLUSION: The good dose coverage and low normal doses achieved for the initial plan was maintained with movements of < or = 5 mm. Beam realignment improved coverage for 10-mm displacements.


Assuntos
Movimento , Próstata , Neoplasias da Próstata/radioterapia , Terapia com Prótons , Idoso , Idoso de 80 Anos ou mais , Fêmur , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Pelve , Próstata/diagnóstico por imagem , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Dosagem Radioterapêutica , Reto , Tomografia Computadorizada por Raios X , Carga Tumoral , Bexiga Urinária
11.
Am J Clin Oncol ; 31(1): 43-8, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18376227

RESUMO

OBJECTIVE: Outcomes after radiotherapy for head and neck mucosal melanoma (MMHN). METHODS: From 1974 to 2005, 17 patients with primary MMHN were treated with radiotherapy. Primary sites included nasal cavity, paranasal sinuses, and oral cavity or oropharynx. Thirteen patients received surgery and postoperative radiotherapy; 4 received definitive radiotherapy. RESULTS: Local control was 79% at 1 and 5 years for 13 of 13 patients treated with surgery and postoperative radiotherapy compared with 1 of 4 patients treated with definitive radiotherapy. Three patients recurred in the neck; 13 patients developed distant metastases. Disease-free survival was 23% at 1 year and 18% at 5 years. Absolute and cause-specific survivals were identical (53% and 28% at 1 and 5 years). CONCLUSION: Locoregional control is relatively high after surgery and adjuvant radiotherapy, but most patients recur in distant sites; approximately one fourth of patients are cured at 5 years. Patients with unresectable tumor may be controlled with definitive radiotherapy.


Assuntos
Neoplasias de Cabeça e Pescoço/radioterapia , Melanoma/radioterapia , Mucosa/efeitos da radiação , Recidiva Local de Neoplasia/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/cirurgia , Humanos , Masculino , Melanoma/patologia , Melanoma/cirurgia , Pessoa de Meia-Idade , Mucosa/patologia , Prognóstico , Dosagem Radioterapêutica , Radioterapia Adjuvante , Taxa de Sobrevida
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