RESUMO
BACKGROUND: Dkk3 (Dickkopf-3) is a secreted glycoprotein known for its proapoptotic and angiogenic activity. The role of Dkk3 in cardiovascular homeostasis is largely unknown. Remarkably, the Dkk3 gene maps within a chromosome segment linked to the hypertensive phenotype in spontaneously hypertensive rats (SHR). METHODS: We used Dkk3-/- mice or stroke-resistant (sr) and stroke-prone (sp) SHR to examine the role of Dkk3 in the central and peripheral regulation of blood pressure (BP). We used lentiviral expression vector to rescue Dkk3 in knockout mice or to induce Dkk3 overexpression or silencing in SHR. RESULTS: Genetic deletion of Dkk3 in mice enhanced BP and impaired endothelium-dependent acetylcholine-induced relaxation of resistance arteries. These alterations were rescued by restoring Dkk3 expression either in the periphery or in the central nervous system (CNS). Dkk3 was required for the constitutive expression of VEGF (vascular endothelium growth factor), and the action of Dkk3 on BP and endothelium-dependent vasorelaxation was mediated by VEGF-stimulated phosphatidylinositol-3-kinase pathway, leading to eNOS (endothelial NO synthase) activation both in resistance arteries and the CNS. The regulatory function of Dkk3 on BP was confirmed in SHR stroke-resistant and SHR stroke-prone in which was blunted in both resistance arteries and brainstem. In SHR stroke-resistant, lentiviral expression vector-induced Dkk3 expression in the CNS largely reduced BP, whereas Dkk3 knock-down further enhanced BP. In SHR stroke-prone challenged with a hypersodic diet, lentiviral expression vector-induced Dkk3 expression in the CNS displayed a substantial antihypertensive effect and delayed the occurrence of stroke. CONCLUSIONS: These findings demonstrate that Dkk3 acts as peripheral and central regulator of BP by promoting VEGF expression and activating a VEGF/Akt (protein kinase B)/eNOS hypotensive axis.
Assuntos
Hipertensão , Acidente Vascular Cerebral , Animais , Camundongos , Ratos , Pressão Sanguínea , Endotélio Vascular/metabolismo , Hipertensão/genética , Óxido Nítrico Sintase Tipo III/metabolismo , Ratos Endogâmicos SHR , Acidente Vascular Cerebral/genética , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular , VasodilataçãoRESUMO
Beyond well-assessed risk factors, cardiovascular events could be also associated with the presence of epigenetic and genetic alterations, such as the methylenetetrahydrofolate-reductase (MTHFR) C677T polymorphism. This gene variant is related to increased circulating levels of homocysteine (Hcy) and cardiovascular risk. However, heterozygous carriers have an augmented risk of cardiovascular accidents independently from normal Hcy levels, suggesting the presence of additional deregulated processes in MTHFR C677T carriers. Here, we hypothesize that targeting Sirtuin 1 (SIRT1) could be an alternative mechanism to control the cardiovascular risk associated to MTHFR deficiency condition. Flow Mediated Dilatation (FMD) and light transmission aggregometry assay were performed in subjects carrying MTHFR C677T allele after administration of resveratrol, the most powerful natural clinical usable compound that owns SIRT1 activating properties. MTHFR C677T carriers with normal Hcy levels revealed endothelial dysfunction and enhanced platelet aggregation associated with SIRT1 downregulation. SIRT1 activity stimulation by resveratrol intake was able to override these abnormalities without affecting Hcy levels. Impaired endothelial function, bleeding time, and wire-induced thrombus formation were rescued in a heterozygous Mthfr-deficient (Mthfr+/-) mouse model after resveratrol treatment. Using a cell-based high-throughput multiplexed screening (HTS) assay, a novel selective synthetic SIRT1 activator, namely ISIDE11, was identified. Ex vivo and in vivo treatment of Mthfr+/- mice with ISIDE11 rescues endothelial vasorelaxation and reduces wire-induced thrombus formation, effects that were abolished by SIRT1 inhibitor. Moreover, platelets from MTHFR C677T allele carriers treated with ISIDE11 showed normalization of their typical hyper-reactivity. These results candidate SIRT1 activation as a new therapeutic strategy to contain cardio and cerebrovascular events in MTHFR carriers.
Assuntos
Homocistinúria , Metilenotetra-Hidrofolato Redutase (NADPH2) , Sirtuína 1 , Trombose , Animais , Genótipo , Homocistinúria/tratamento farmacológico , Homocistinúria/metabolismo , Humanos , Metilenotetra-Hidrofolato Redutase (NADPH2)/deficiência , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Camundongos , Espasticidade Muscular , Transtornos Psicóticos/metabolismo , Resveratrol/farmacologia , Sirtuína 1/genética , Sirtuína 1/metabolismo , Trombose/tratamento farmacológico , Trombose/genética , Trombose/metabolismo , Trombose/prevenção & controleRESUMO
OBJECTIVE: To determine the influence of rectal hydrogel spacer placement (HSP) on late rectal toxicity outcomes in prostate cancer patients treated with low-dose-rate (LDR) brachytherapy, with or without supplemental external beam radiotherapy (EBRT). PATIENTS AND METHODS: A total of 224 patients underwent LDR brachytherapy with HSP, as monotherapy or combined with EBRT, between January 2016 and December 2019. Dosimetric variables reflecting the extent of rectal sparing and late rectal toxicity outcomes were evaluated. This spacer cohort was retrospectively compared to a similar patient group (n = 139) in whom HSP was not used. RESULTS: Hydrogel spacer placement was associated with significantly reduced rectal doses for all dosimetric variables; the median percentage rectal dose to 1 cc of rectum and rectal dose to 2 cc of rectum of the spacer cohort were all significantly lower compared to the non-spacer cohort. The incidence rates of overall (any grade) and grade ≥2 rectal toxicity were lower in patients with HSP compared to patients who did not undergo HSP: 12% and 1.8% vs 31% and 5.8%, respectively. The 3-year cumulative incidence of overall rectal toxicity was significantly lower with HSP than without (15% vs 33%; P < 0.001), corresponding to an overall rectal toxicity reduction on univariable analysis (hazard ratio 0.45, 95% confidence interval 0.28-0.73; P = 0.001). In this patient cohort treated with prostate brachytherapy, none of the urethral dosimetric variables or the presence or absence of HSP was associated with late urinary toxicity. CONCLUSION: Hydrogel rectal spacer placement is a safe procedure, associated with significantly reduced rectal dose. HSP translates to a decrease in overall late rectal toxicity in patients receiving dose-escalated brachytherapy-based procedures.
Assuntos
Braquiterapia , Neoplasias da Próstata , Braquiterapia/efeitos adversos , Braquiterapia/métodos , Humanos , Hidrogéis/efeitos adversos , Masculino , Próstata , Neoplasias da Próstata/etiologia , Neoplasias da Próstata/radioterapia , Dosagem Radioterapêutica , Reto , Estudos RetrospectivosRESUMO
BACKGROUND: Coronavirus disease 2019 (COVID-19) is a recently recognized viral infective disease which can be complicated by acute respiratory stress syndrome (ARDS) and cardiovascular complications including severe arrhythmias, acute coronary syndromes, myocarditis and pulmonary embolism. The aim of the present study was to identify the clinical conditions and echocardiographic parameters associated with in-hospital mortality in COVID-19. METHODS: This is a multicentre retrospective observational study including seven Italian centres. Patients hospitalized with COVID-19 from 1 March to 22 April 2020 were included into study population. The association between baseline variables and risk of in-hospital mortality was assessed through multivariable logistic regression and competing risk analyses. RESULTS: Out of 1401 patients admitted at the participating centres with confirmed diagnosis of COVID-19, 226 (16.1%) underwent transthoracic echocardiography (TTE) and were included in the present analysis. In-hospital death occurred in 68 patients (30.1%). At multivariable analysis, left ventricular ejection fraction (LVEF, P < .001), tricuspid annular plane systolic excursion (TAPSE, P < .001) and ARDS (P < .001) were independently associated with in-hospital mortality. At competing risk analysis, we found a significantly higher risk of mortality in patients with ARDS vs those without ARDS (HR: 7.66; CI: 3.95-14.8), in patients with TAPSE ≤17 mm vs those with TAPSE >17 mm (HR: 5.08; CI: 3.15-8.19) and in patients with LVEF ≤50% vs those with LVEF >50% (HR: 4.06; CI: 2.50-6.59). CONCLUSIONS: TTE might be a useful tool in risk stratification of patients with COVID-19. In particular, reduced LVEF and reduced TAPSE may help to identify patients at higher risk of death during hospitalization.
Assuntos
COVID-19/mortalidade , Mortalidade Hospitalar , Síndrome do Desconforto Respiratório/epidemiologia , Disfunção Ventricular Esquerda/epidemiologia , Disfunção Ventricular Direita/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Ecocardiografia , Feminino , Humanos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , SARS-CoV-2 , Volume Sistólico , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Direita/diagnóstico por imagemRESUMO
AIMS: Here, we aimed to determine the therapeutic effect of longevity-associated variant (LAV)-BPIFB4 gene therapy on atherosclerosis. METHODS AND RESULTS: ApoE knockout mice (ApoE-/-) fed a high-fat diet were randomly allocated to receive LAV-BPIFB4, wild-type (WT)-BPIFB4, or empty vector via adeno-associated viral vector injection. The primary endpoints of the study were to assess (i) vascular reactivity and (ii) atherosclerotic disease severity, by Echo-Doppler imaging, histology and ultrastructural analysis. Moreover, we assessed the capacity of the LAV-BPIFB4 protein to shift monocyte-derived macrophages of atherosclerotic mice and patients towards an anti-inflammatory phenotype. LAV-BPIFB4 gene therapy rescued endothelial function of mesenteric and femoral arteries from ApoE-/- mice; this effect was blunted by AMD3100, a CXC chemokine receptor type 4 (CXCR4) inhibitor. LAV-BPIFB4-treated mice showed a CXCR4-mediated shift in the balance between Ly6Chigh/Ly6Clow monocytes and M2/M1 macrophages, along with decreased T cell proliferation and elevated circulating levels of interleukins IL-23 and IL-27. In vitro conditioning with LAV-BPIFB4 protein of macrophages from atherosclerotic patients resulted in a CXCR4-dependent M2 polarization phenotype. Furthermore, LAV-BPIFB4 treatment of arteries explanted from atherosclerotic patients increased the release of atheroprotective IL-33, while inhibiting the release of pro-inflammatory IL-1ß, inducing endothelial nitric oxide synthase phosphorylation and restoring endothelial function. Finally, significantly lower plasma BPIFB4 was detected in patients with pathological carotid stenosis (>25%) and intima media thickness >2 mm. CONCLUSION: Transfer of the LAV of BPIFB4 reduces the atherogenic process and skews macrophages towards an M2-resolving phenotype through modulation of CXCR4, thus opening up novel therapeutic possibilities in cardiovascular disease.
Assuntos
Aterosclerose , Placa Aterosclerótica , Idoso , Animais , Apolipoproteínas E , Aterosclerose/genética , Espessura Intima-Media Carotídea , Feminino , Humanos , Inflamação , Peptídeos e Proteínas de Sinalização Intercelular , Longevidade , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Knockout para ApoE , Pessoa de Meia-Idade , Fosfoproteínas , Receptores CXCR4RESUMO
PURPOSE/OBJECTIVES: Three-dimensional (3D) printing is recognized as an effective clinical and educational tool in procedurally intensive specialties. However, it has a nascent role in radiation oncology. The goal of this investigation is to clarify the extent to which 3D printing applications are currently being used in radiation oncology through a systematic review of the literature. MATERIALS/METHODS: A search protocol was defined according to preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. Included articles were evaluated using parameters of interest including: year and country of publication, experimental design, sample size for clinical studies, radiation oncology topic, reported outcomes, and implementation barriers or safety concerns. RESULTS: One hundred and three publications from 2012 to 2019 met inclusion criteria. The most commonly described 3D printing applications included quality assurance phantoms (26%), brachytherapy applicators (20%), bolus (17%), preclinical animal irradiation (10%), compensators (7%), and immobilization devices (5%). Most studies were preclinical feasibility studies (63%), with few clinical investigations such as case reports or series (13%) or cohort studies (11%). The most common applications evaluated within clinical settings included brachytherapy applicators (44%) and bolus (28%). Sample sizes for clinical investigations were small (median 10, range 1-42). A minority of articles described basic or translational research (11%) and workflow or cost evaluation studies (3%). The number of articles increased over time (P < 0.0001). While outcomes were heterogeneous, most studies reported successful implementation of accurate and cost-effective 3D printing methods. CONCLUSIONS: Three-dimensional printing is rapidly growing in radiation oncology and has been implemented effectively in a diverse array of applications. Although the number of 3D printing publications has steadily risen, the majority of current reports are preclinical in nature and the few clinical studies that do exist report on small sample sizes. Further dissemination of ongoing investigations describing the clinical application of developed 3D printing technologies in larger cohorts is warranted.
Assuntos
Braquiterapia , Radioterapia (Especialidade) , Animais , Imagens de Fantasmas , Impressão TridimensionalRESUMO
PURPOSE: To develop an Eclipse plug-in (MLC_MODIFIER) that automatically modifies control points to expose fiducials obscured by MLC during VMAT, thereby facilitating tracking using periodic MV/kV imaging. METHOD: Three-dimensional fiducial tracking was performed during VMAT by pairing short-arc (3°) MV digital tomosynthesis (DTS) images to triggered kV images. To evaluate MLC_MODIFIER efficacy, two cohorts of patients were considered. For first 12 patients, plans were manually edited to expose one fiducial marker. Next for 15 patients, plans were modified using MLC_MODIFIER script. MLC_MODIFIER evaluated MLC apertures at appropriate angles for marker visibility. Angles subtended by control points were compressed and low-dose "imaging" control points were inserted and exposed one marker with 1 cm margin. Patient's images were retrospectively reviewed to determine rate of MV registration failures. Failure categories were poor DTS image quality, MLC blockage of fiducials, or unknown reasons. Dosimetric differences in rectum, bladder, and urethra D1 cc, PTV maximum dose, and PTV dose homogeneity (PTV HI) were evaluated. Statistical significance was evaluated using Fisher's exact and Student's t test. RESULT: Overall MV registration failures, failures due to poor image quality, MLC blockage, and unknown reasons were 33% versus 8.9% (P < 0.0001), 8% versus 6.4% (P < 0.05), 13.6% versus 0.1% (P < 0.0001), and 7.6% versus 2.4% (P < 0.0001) for manually edited and MLC_MODIFIER plans, respectively. PTV maximum and HI increased on average from unmodified plans by 2.1% and 0.3% (P < 0.004) and 22.0% and 3.3% (P < 0.004) for manually edited and MLC_MODIFIED plans, respectively. Changes in bladder, rectum, and urethra D1CC were similar for each method and less than 0.7%. CONCLUSION: Increasing fiducial visibility via an automated process comprised of angular compression of control points and insertion of additional "imaging" control points is feasible. Degradation of plan quality is minimal. Fiducial detection and registration success rates are significantly improved compared to manually edited apertures.
Assuntos
Marcadores Fiduciais , Imagem Molecular/normas , Neoplasias da Próstata/radioterapia , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Guiada por Imagem/instrumentação , Radioterapia de Intensidade Modulada/métodos , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional , Masculino , Movimento , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Dosagem Radioterapêutica , Radioterapia Guiada por Imagem/métodos , Estudos RetrospectivosRESUMO
Evolutionary forces select genetic variants that allow adaptation to environmental stresses. The genomes of centenarian populations could recapitulate the evolutionary adaptation model and reveal the secrets of disease resistance shown by these individuals. Indeed, longevity phenotype is supposed to have a genetic background able to survive or escape to age-related diseases. Among these, cardiovascular diseases (CVDs) are the most lethal and their major risk factor is aging and the associated frailty status. One example of genetic evolution revealed by the study of centenarians genome is the four missense Single Nucleotide Polymorphisms (SNPs) haplotype in bactericidal/permeability-increasing fold-containing family B, member 4 (BPIFB4) locus that is enriched in long living individuals: the longevity associated variant (LAV). Indeed, LAV-BPIFB4 is able to improve endothelial function and revascularization through the increase of endothelial nitric oxide synthase (eNOS) dependent nitric oxide production. This review recapitulates the beneficial effects of LAV-BPIFB4 and its therapeutic potential for the treatment of CVDs.
Assuntos
Doenças Cardiovasculares/genética , Longevidade/genética , Fosfoproteínas/genética , Polimorfismo de Nucleotídeo Único , Seleção Genética , Evolução Molecular , Humanos , Peptídeos e Proteínas de Sinalização IntercelularRESUMO
Diabetes mellitus is a common disease that affects 3â»5% of the general population in Italy. In some countries of northern Europe or in North America, it can even affect 6â»8% of the population. Of great concern is that the number of cases of diabetes is constantly increasing, probably due to the increase in obesity and the sedentary nature of the population. According to the World Health Organization, in the year 2030 there will be 360 million people with diabetes, compared to 170 million in 2000. This has important repercussions on the lives of patients and their families, and on health systems that offer assistance to patients. In this review, we try to describe in an organized way the pathophysiological continuity between diabetes mellitus, endothelial dysfunction, and platelet hyperaggregation, highlighting the main molecular mechanisms involved and the interconnections.
Assuntos
Diabetes Mellitus/fisiopatologia , Endotélio Vascular/fisiopatologia , Doenças Vasculares/fisiopatologia , Animais , Humanos , Modelos Biológicos , Agregação PlaquetáriaRESUMO
A growing number of evidences report that aging represents the major risk factor for the development of cardio and cerebrovascular diseases. Understanding Aging from a genetic, biochemical and physiological point of view could be helpful to design a better medical approach and to elaborate the best therapeutic strategy to adopt, without neglecting all the risk factors associated with advanced age. Of course, the better way should always be understanding risk-to-benefit ratio, maintenance of independence and reduction of symptoms. Although improvements in treatment of cardiovascular diseases in the elderly population have increased the survival rate, several studies are needed to understand the best management option to improve therapeutic outcomes. The aim of this review is to give a 360° panorama on what goes on in the fragile ecosystem of elderly, why it happens and what we can do, right now, with the tools at our disposal to slow down aging, until new discoveries on aging, cardio and cerebrovascular diseases are at hand.
Assuntos
Envelhecimento , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Transtornos Cerebrovasculares/epidemiologia , Transtornos Cerebrovasculares/etiologia , Fatores Etários , Animais , Vasos Sanguíneos/fisiologia , Vasos Sanguíneos/fisiopatologia , Suscetibilidade a Doenças , Endotélio/metabolismo , Endotélio/fisiopatologia , Predisposição Genética para Doença , Coração/fisiologia , Coração/fisiopatologia , Humanos , Estresse Oxidativo , Risco , VasodilataçãoRESUMO
OBJECTIVE: The purpose was to compare local control (LC), overall survival (OS) and dose to the organs at risk (OAR) in women with locally advanced cervical cancer treated with MR-guided versus CT-guided interstitial brachytherapy (BT). METHODS: 56 patients (29 MR, 27 CT) were treated with high-dose-rate (HDR) interstitial BT between 2005-2015. The MR patients had been prospectively enrolled on a Phase II clinical trial. Data were analyzed using Kaplan-Meier (K-M) and Cox proportional hazards statistical modeling in JMP® & R®. RESULTS: Median follow-up time was 19.7months (MR group) and 18.4months (CT group). There were no statistically significant differences in patient age at diagnosis, histology, percent with tumor size >4cm, grade, FIGO stage or lymph node involvement between the groups. Patients in the MR group had more lymphovascular involvement compared to patients in the CT group (p<0.01). When evaluating plans generated, there were no statistically significant differences in median cumulative dose to the high-risk clinical target volume or the OAR. 2-year K-M LC rates for MR-based and CT-based treatments were 96% and 87%, respectively (log-rank p=0.65). At 2years, OS was significantly better in the MR-guided cohort (84% vs. 56%, p=0.036). On multivariate analysis, squamous histology was associated with longer OS (HR 0.23, 95% CI 0.07-0.72) in a model with MR BT (HR 0.35, 95% CI 0.08-1.18). There was no difference in toxicities between CT and MR BT. CONCLUSION: In this population of locally advanced cervical-cancer patients, MR-guided HDR BT resulted in estimated 96% 2-year local control and excellent survival and toxicity rates.
Assuntos
Braquiterapia/métodos , Imageamento por Ressonância Magnética/métodos , Tomografia Computadorizada por Raios X/métodos , Neoplasias do Colo do Útero/diagnóstico por imagem , Neoplasias do Colo do Útero/radioterapia , Adulto , Idoso , Relação Dose-Resposta à Radiação , Feminino , Humanos , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Estudos Prospectivos , Resultado do Tratamento , Neoplasias do Colo do Útero/patologiaRESUMO
RATIONALE: Long living individuals show delay of aging, which is characterized by the progressive loss of cardiovascular homeostasis, along with reduced endothelial nitric oxide synthase activity, endothelial dysfunction, and impairment of tissue repair after ischemic injury. OBJECTIVE: Exploit genetic analysis of long living individuals to reveal master molecular regulators of physiological aging and new targets for treatment of cardiovascular disease. METHODS AND RESULTS: We show that the polymorphic variant rs2070325 (Ile229Val) in bactericidal/permeability-increasing fold-containing-family-B-member-4 (BPIFB4) associates with exceptional longevity, under a recessive genetic model, in 3 independent populations. Moreover, the expression of BPIFB4 is instrumental to maintenance of cellular and vascular homeostasis through regulation of protein synthesis. BPIFB4 phosphorylation/activation by protein-kinase-R-like endoplasmic reticulum kinase induces its complexing with 14-3-3 and heat shock protein 90, which is facilitated by the longevity-associated variant. In isolated vessels, BPIFB4 is upregulated by mechanical stress, and its knock-down inhibits endothelium-dependent vasorelaxation. In hypertensive rats and old mice, gene transfer of longevity-associated variant-BPIFB4 restores endothelial nitric oxide synthase signaling, rescues endothelial dysfunction, and reduces blood pressure levels. Furthermore, BPIFB4 is implicated in vascular repair. BPIFB4 is abundantly expressed in circulating CD34(+) cells of long living individuals, and its knock-down in endothelial progenitor cells precludes their capacity to migrate toward the chemoattractant SDF-1. In a murine model of peripheral ischemia, systemic gene therapy with longevity-associated variant-BPIFB4 promotes the recruitment of hematopoietic stem cells, reparative vascularization, and reperfusion of the ischemic muscle. CONCLUSIONS: Longevity-associated variant-BPIFB4 may represent a novel therapeutic tool to fight endothelial dysfunction and promote vascular reparative processes.
Assuntos
Células Progenitoras Endoteliais/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Longevidade/genética , Músculo Esquelético/irrigação sanguínea , Neovascularização Fisiológica , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Proteínas 14-3-3/metabolismo , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Animais , Pressão Sanguínea , Movimento Celular , Modelos Animais de Doenças , Europa (Continente) , Feminino , Estudos de Associação Genética , Terapia Genética , Genótipo , Células HEK293 , Proteínas de Choque Térmico HSP90/metabolismo , Membro Posterior , Humanos , Hipertensão/genética , Hipertensão/metabolismo , Hipertensão/fisiopatologia , Hipertensão/terapia , Peptídeos e Proteínas de Sinalização Intercelular , Isquemia/genética , Isquemia/metabolismo , Isquemia/fisiopatologia , Isquemia/terapia , Masculino , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Óxido Nítrico Sintase Tipo III/metabolismo , Fenótipo , Fosforilação , Interferência de RNA , Ratos Endogâmicos SHR , Transdução de Sinais , Estresse Mecânico , Transfecção , Estados Unidos , Vasodilatação , eIF-2 Quinase/metabolismoRESUMO
After publication of the original article [1], it was noticed that one of the affiliations of author Carmine Vecchione was missing.
RESUMO
BACKGROUND: NAFLD is associated to Insulin Resistance (IR). IR is responsible for Endothelial Dysfunction (ED) through the impairment of eNOS function. Although eNOS derangement has been demonstrated in experimental models, no studies have directly shown that eNOS dysfunction is associated with NAFLD in humans. The aim of this study is to investigate eNOS function in NAFLD patients. METHODS: Fifty-four NAFLD patients were consecutively enrolled. All patients underwent clinical and laboratory evaluation and liver biopsy. Patients were divided into two groups by the presence of NAFL or NASH. We measured vascular reactivity induced by patients' platelets on isolated mice aorta rings. Immunoblot assays for platelet-derived phosphorylated-eNOS (p-eNOS) and immunohistochemistry for hepatic p-eNOS have been performed to evaluate eNOS function in platelets and liver specimens. Flow-mediated-dilation (FMD) was also performed. Data were compared with healthy controls. RESULTS: Twenty-one (38, 8%) patients had NAFL and 33 (61, 7%) NASH. No differences were found between groups and controls except for HOMA and insulin (p < 0.0001). Vascular reactivity demonstrated a reduced function induced from NAFLD platelets as compared with controls (p < 0.001), associated with an impaired p-eNOS in both platelets and liver (p < 0.001). NAFL showed a higher impairment of eNOS phosphorylation in comparison to NASH (p < 0.01). In contrast with what observed in vitro, the vascular response by FMD was worse in NASH as compared with NAFL. CONCLUSIONS: Our data showed, for the first time in humans, that NAFLD patients show a marked eNOS dysfunction, which may contribute to a higher CV risk. eNOS dysfunction observed in platelets and liver tissue didn't match with FMD.
Assuntos
Fígado/irrigação sanguínea , Óxido Nítrico Sintase Tipo III/metabolismo , Hepatopatia Gordurosa não Alcoólica/enzimologia , Hepatopatia Gordurosa não Alcoólica/fisiopatologia , Vasodilatação , Adulto , Animais , Aorta/metabolismo , Biópsia , Plaquetas/metabolismo , Estudos de Casos e Controles , Fígado Gorduroso/patologia , Fígado Gorduroso/fisiopatologia , Feminino , Humanos , Resistência à Insulina , Fígado/patologia , Masculino , Camundongos , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/patologia , Fosforilação , Estudos ProspectivosRESUMO
BACKGROUND: Pentraxin 3 (PTX3), the prototype of long pentraxins, has been described to be associated with endothelial dysfunction in different cardiovascular disorders. No study has yet evaluated the possible direct effect of PTX3 on vascular function. METHODS AND RESULTS: Through in vitro experiments of vascular reactivity and ultrastructural analyses, we demonstrate that PTX3 induces dysfunction and morphological changes in the endothelial layer through a P-selectin/matrix metalloproteinase-1 pathway. The latter hampered the detachment of endothelial nitric oxide synthase from caveolin-1, leading to an impairment of nitric oxide signaling. In vivo studies showed that administering PTX3 to wild-type mice induced endothelial dysfunction and increased blood pressure, an effect absent in P-selectin-deficient mice. In isolated human umbilical vein endothelial cells, PTX3 significantly blunted nitric oxide production through the matrix metalloproteinase-1 pathway. Finally, using ELISA, we found that hypertensive patients (n=31) have higher plasma levels of PTX3 and its mediators P-selectin and matrix metalloproteinase-1 than normotensive subjects (n=21). CONCLUSIONS: Our data show for the first time a direct role of PTX3 on vascular function and blood pressure homeostasis, identifying the molecular mechanisms involved. The findings in humans suggest that PTX3, P-selectin, and matrix metalloproteinase-1 may be novel biomarkers that predict the onset of vascular dysfunction in hypertensive patients.
Assuntos
Proteína C-Reativa/fisiologia , Endotélio Vascular/fisiopatologia , Hipertensão/fisiopatologia , Metaloproteinase 1 da Matriz/fisiologia , Selectina-P/fisiologia , Componente Amiloide P Sérico/fisiologia , Animais , Pressão Sanguínea , Caveolina 1/metabolismo , Membrana Celular/metabolismo , Células Cultivadas , Células Endoteliais da Veia Umbilical Humana , Humanos , Metaloproteinase 1 da Matriz/deficiência , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas do Tecido Nervoso/fisiologia , Óxido Nítrico/metabolismo , Receptores de IgG/deficiência , Transdução de Sinais/fisiologia , VasodilataçãoRESUMO
PURPOSE: To assess whether R2* mapping with a standard Monoexponential (ME) or a Gaussian Augmentation of the Monoexponential (GAME) decay model better characterizes gradient-echo signal decays in gynecological cancers after external beam radiation therapy at 3T, and evaluate implications of modeling for noninvasive identification of intratumoral hypoxia. MATERIALS AND METHODS: Multi-gradient-echo signals were acquired on 25 consecutive patients with gynecologic cancers and three healthy participants during inhalation of different oxygen concentrations at 3T. Data were fitted with both ME and GAME models. Models were compared using F-tests in tumors and muscles in patients, muscles, cervix, and uterus in healthy participants, and across oxygenation levels. RESULTS: GAME significantly improved fitting over ME (P < 0.05): Improvements with GAME covered 34% of tumor regions-of-interest on average, ranging from 6% (of a vaginal tumor) to 68% (of a cervical tumor) in individual tumors. Improvements with GAME were more prominent in areas that would be assumed hypoxic based on ME alone, reaching 90% as ME R2* approached 100 Hz. Gradient echo decay parameters at different oxygenation levels were not significantly different (P = 0.81). CONCLUSION: R2* may prove sensitive to hypoxia; however, inaccurate representations of underlying data may limit the success of quantitative assessments. Although the degree to which R2 or σ values correlate with hypoxia remains unknown, improved characterization with GAME increases the potential for determining any correlates of fit parameters with biomarkers, such as oxygenation status. J. MAGN. RESON. IMAGING 2016;44:1020-1030.
Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias dos Genitais Femininos/diagnóstico por imagem , Neoplasias dos Genitais Femininos/metabolismo , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Modelos Estatísticos , Oxigênio/metabolismo , Adulto , Idoso , Simulação por Computador , Feminino , Humanos , Aumento da Imagem/métodos , Pessoa de Meia-Idade , Distribuição Normal , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Hipóxia TumoralRESUMO
OBJECTIVE: To determine prognostic factors for progression-free survival (PFS) and overall survival (OS) for stage I-II cervical-cancer patients treated using computed-tomography (CT)-planned high-dose-rate (HDR) intracavitary brachytherapy (BT). METHODS: A total of 150 patients were treated for Stage I-II cervical cancer using CT-planned BT between 4/2004 and 10/2014. Of these, 128 were eligible for inclusion. Kaplan-Meier local control (LC), pelvic control (PC), overall survival (OS), and PFS estimates were calculated. RESULTS: After a median follow-up of 30months, the 2-year LC rate was 96%, PFS was 88%, and OS was 88%. Overall, 18 patients (14%) experienced any recurrence (AR), 8 had distant recurrence only and 10 had a combination of local, pelvic, regional, and distant recurrence. No patients had LR only. A prognostic factor for AR was tumor size >4cm (p=0.01). Patients with tumors >4cm were 3.3 times more likely to have AR than those with tumors ≤4cm (hazard ratio [HR]=3.3; 95% confidence interval [CI] 1.28-9.47). Point A was 85% of prescription for tumors < 4 cm and decreased approximately 3% over 5 fractions compared to 90% of prescription for tumors > 4 cm that decreased approximately 4% over 5 fractions. Two patients (2%) experienced grade≥2 late toxicity. There were no acute or late grade≥3 toxicities. CONCLUSION: CT-planned BT resulted in excellent local control and survival. Large tumor size was associated with an increased risk of recurrence outside the radiation field and worse PFS and OS. A volume-optimized plan treated a smaller area than a point A standard plan for patients with Stage I-II cervical cancer that have received chemoradiation. Given the outstanding LC achieved with modern therapy including chemoradiation, HDR, and image-based BT, further efforts to combat spread outside the radiation field with novel therapies are warranted.
Assuntos
Adenocarcinoma/radioterapia , Braquiterapia/métodos , Carcinoma Adenoescamoso/radioterapia , Carcinoma de Células Escamosas/radioterapia , Recidiva Local de Neoplasia/epidemiologia , Planejamento da Radioterapia Assistida por Computador/métodos , Neoplasias do Colo do Útero/radioterapia , Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Adenoescamoso/diagnóstico por imagem , Carcinoma Adenoescamoso/patologia , Carcinoma de Células Escamosas/diagnóstico por imagem , Carcinoma de Células Escamosas/patologia , Quimiorradioterapia , Intervalo Livre de Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Fatores de Tempo , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Carga Tumoral , Neoplasias do Colo do Útero/diagnóstico por imagem , Neoplasias do Colo do Útero/patologia , Adulto JovemRESUMO
The acute phase protein Pentraxin 3 (PTX3) plays a non-redundant role as a soluble pattern recognition receptor for selected pathogens and it represents a rapid biomarker for primary local activation of innate immunity and inflammation. Recent evidence indicates that PTX3 exerts an important role in modulating the cardiovascular system in humans and experimental models. In particular, there are conflicting points concerning the effects of PTX3 in cardiovascular diseases (CVD) since several observations indicate a cardiovascular protective effect of PTX3 while others speculate that the increased plasma levels of PTX3 in subjects with CVD correlate with disease severity and with poor prognosis in elderly patients. In the present review, we discuss the multifaceted effects of PTX3 on the cardiovascular system focusing on its involvement in atherosclerosis, endothelial function, hypertension, myocardial infarction and angiogenesis. This may help to explain how the specific modulation of PTX3 such as the use of different dosing, time, and target organs could help to contain different vascular diseases. These opposite actions of PTX3 will be emphasized concerning the modulation of cardiovascular system where potential therapeutic implications of PTX3 in humans are discussed.
RESUMO
PURPOSE: To develop an active MR-tracking system to guide placement of metallic devices for radiation therapy. METHODS: An actively tracked metallic stylet for brachytherapy was constructed by adding printed-circuit micro-coils to a commercial stylet. The coil design was optimized by electromagnetic simulation, and has a radio-frequency lobe pattern extending â¼5 mm beyond the strong B0 inhomogeneity region near the metal surface. An MR-tracking sequence with phase-field dithering was used to overcome residual effects of B0 and B1 inhomogeneities caused by the metal, as well as from inductive coupling to surrounding metallic stylets. The tracking system was integrated with a graphical workstation for real-time visualization. The 3 Tesla MRI catheter-insertion procedures were tested in phantoms and ex vivo animal tissue, and then performed in three patients during interstitial brachytherapy. RESULTS: The tracking system provided high-resolution (0.6 × 0.6 × 0.6 mm(3) ) and rapid (16 to 40 frames per second, with three to one phase-field dithering directions) catheter localization in phantoms, animals, and three gynecologic cancer patients. CONCLUSION: This is the first demonstration of active tracking of the shaft of metallic stylet in MR-guided brachytherapy. It holds the promise of assisting physicians to achieve better targeting and improving outcomes in interstitial brachytherapy.
Assuntos
Artefatos , Braquiterapia/instrumentação , Braquiterapia/métodos , Marcadores Fiduciais , Neoplasias dos Genitais Femininos/radioterapia , Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/instrumentação , Imageamento Tridimensional/métodos , Imageamento por Ressonância Magnética/instrumentação , Imageamento por Ressonância Magnética/métodos , Metais , Radioterapia Assistida por Computador/instrumentação , Radioterapia Assistida por Computador/métodos , Radioterapia Guiada por Imagem/instrumentação , Radioterapia Guiada por Imagem/métodos , Animais , Galinhas , Gráficos por Computador , Simulação por Computador , Campos Eletromagnéticos , Desenho de Equipamento , Feminino , Aumento da Imagem/instrumentação , Aumento da Imagem/métodos , Imagens de Fantasmas , SoftwareRESUMO
BACKGROUND: Diffusing alpha-emitters Radiation Therapy ("DaRT") is a promising new modality for the treatment of solid tumors. Interstitial sources containing 224 Ra are inserted into the tumor, producing alpha particles via the decay of 224 Ra and its daughters. The alpha particles are able to produce a "kill region" of several mm due to the diffusion of the alpha-emitting atoms. The Diffusion-Leakage (D-L) model has been proposed to describe the movement of the alpha-emitters used in DaRT in tumor tissue. PURPOSE: To date, estimating the dose delivered under the D-L model has been accomplished with numerical solutions based on finite difference methods, namely DART1D and DART2D, as well as with asymptotic expressions for the long time limit. The aim of this work is to develop a flexible method of finite elements for solving the D-L model and to validate prior solutions of the D-L model. METHODS: We develop a two-dimensional finite element solution to the D-L model implemented using the FEniCS software library. Our approach solves the variational formulation of the D-L equations on an unstructured mesh of triangular Lagrangian elements. We calculate the local dose in the mid- and axial planes of the source and validate our results against the one- and two-dimensional solutions obtained using the previously proposed numerical scheme, DART1D and DART2D. We use our model to estimate the change in dose in the source midplane as a function of the physical parameters used in the D-L model. RESULTS: The local dose at the end of a 30 day treatment period estimated by our numerical method differs from DART1D and DART2D by less than 1% in the source midplane and less than 3% along the source axis over clinically relevant distances, with the largest discrepancies in high gradient areas where the Finite Element Method (FEM) mesh has a higher element density. We find that within current experimentally estimated ranges for D-L model parameters, the dose in the source midplane at a distance of 2 mm can vary by over a factor of 3. CONCLUSIONS: The 2D finite element model reproduces the calculated dose obtained with DART1D and DART2D under the assumptions D-L model. The variation in predicted dose within current experimental ranges for model parameters suggests the necessity of further studies to better determine their statistical distributions. Finally, the FEM model can be used to calculate dose from DaRT in a variety of realistic 2D geometries beyond the D-L model.