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1.
Catheter Cardiovasc Interv ; 99(4): 998-1005, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35182020

RESUMO

OBJECTIVES: We aim to define whether the timing of microaxial left ventricular assist device (IMLVAD) implantation might impact on mortality in acute myocardial infarction (AMI) cardiogenic shock (CS) patients who underwent primary percutaneous coronary intervention (PPCI). BACKGROUND: Despite the widespread use of PPCI, mortality in patients with AMI and CS remains high. Mechanical circulatory support is a promising bridge to recovery strategy, but evidence on its benefit is still inconclusive and the optimal timing of its utilization remains poorly explored. METHODS: We compared clinical outcomes of upstream IMLVAD use before PPCI versus bailout use after PPCI in patients with AMI CS. A systematic review and meta-analysis of studies comparing the two strategies were performed. Effect size was reported as odds ratio (OR) using bailout as reference group and a random effect model was used. Study-level risk estimates were pooled through the generic inverse variance method (random effect model). RESULTS: A total of 11 observational studies were identified, including a pooled population of 6759 AMI-CS patients. Compared with a bailout approach, upstream IMLVAD was associated with significant reduction of 30-day (OR = 0.65; 95% confidence interval [CI] = 0.51-0.82; I2 = 43%, adjusted OR = 0.54; 95% CI = 0.37-0.59; I2 = 3%, test for subgroup difference p = 0.30), 6-month (OR = 0.51; 95% CI = 0.27-0.96; I2 = 66%), and 1-year (OR = 0.56; 95% CI = 0.39-0.79; I2 = 0%) all-cause mortality. Incidence of access-related bleeding, acute limb ischemia and transfusion outcomes were similar between the two strategies. CONCLUSION: In patients with AMI-CS undergoing PPCI, upstream IMLVAD was associated with reduced early and midterm all-cause mortality when compared with a bailout strategy.


Assuntos
Coração Auxiliar , Infarto do Miocárdio , Intervenção Coronária Percutânea , Angioplastia/efeitos adversos , Coração Auxiliar/efeitos adversos , Humanos , Balão Intra-Aórtico/efeitos adversos , Infarto do Miocárdio/complicações , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/terapia , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/métodos , Choque Cardiogênico/diagnóstico , Choque Cardiogênico/etiologia , Choque Cardiogênico/terapia , Resultado do Tratamento
2.
Am J Ind Med ; 59(7): 509-21, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27219869

RESUMO

BACKGROUND: Experimental rodent bioassays performed up to now have failed to provide conclusive confirmation of the carcinogenicity of extremely low frequency magnetic fields (ELFMF). OBJECTIVES: To evaluate the potential synergistic carcinogenic effects of concurrent exposure to ELFMF and formaldehyde in four groups of male and female Sprague-Dawley rats. METHODS: One group was exposed from prenatal life until natural death to S-50 Hz MF and to formaldehyde in drinking water from 6 weeks of age for 104 weeks, two groups were treated only with formaldehyde or only with MF and one group served as untreated control. RESULTS: Compared to untreated controls, exposure to MF and formaldehyde causes in males a statistically significant increased incidence of malignant tumors (P ≤ 0.01), thyroid C-cell carcinomas (P ≤ 0.01), and hemolymphoreticular neoplasias (P ≤ 0.05). No statistically significant differences were observed among female groups. CONCLUSIONS: Life-span exposure to MF and formaldehyde induces statistically significant carcinogenic effects in male rats. Am. J. Ind. Med. 59:509-521, 2016. © 2016 Wiley Periodicals, Inc.


Assuntos
Cocarcinogênese , Formaldeído/efeitos adversos , Neoplasias Hematológicas/etiologia , Campos Magnéticos/efeitos adversos , Neoplasias da Glândula Tireoide/etiologia , Animais , Carcinógenos , Feminino , Estimativa de Kaplan-Meier , Leucemia/etiologia , Linfoma/etiologia , Masculino , Ratos , Ratos Sprague-Dawley , Fatores Sexuais , Neoplasias da Glândula Tireoide/patologia
3.
Electromagn Biol Med ; 34(2): 147-50, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26098527

RESUMO

Several years ago just before Christmas, in a small meeting room at the Institute of Pharmacology at the University of Rome, we had the opportunity to attend a meeting on "The role of QED in medicine" by Emilio Del Giudice and Giuliano Preparata. Before that meeting, we were more oriented towards a mechanistic view of Biochemistry and Medicine, believing that chemical reactions could only take place when a random collision between molecules with a gain in energy takes place. We envisioned water as just a solvent in which was possible to dissolve a solute. After we listened to Giuliano's and Emilio's speech on the "New physics of water", and on "The possible origin of coherence in cell, tissues and the interaction of very weak and low frequency magnetic fields with the ions, systems of the cell", we realized that living organisms are complex electrochemical systems which evolved in a relatively narrow range of well-defined environmental parameters. Environmental natural electro-magnetic fields are an ubiquitous factor in nature. If nature gave certain organisms the ability to receive information about the environment via invisible electromagnetic signals, then there must also the capability to discriminate between significant and meaningless ones. Bearing in mind that electromagnetic fields can be perceived by living organisms by means a resonance effect, we should not be amazed if they can be able to induce different biological effects. The work that we will present in memory of Emilio is based on the hypotheses that an aqueous system a chemical differentiation agent such as retinoic acid (RA) were electronically captured and transferred to the culture medium of Neuroblastoma Cell Line (LAN-5) and the proliferation rate was assessed to assess cell responses to the electromagnetic information transfer through the aqueous system. Like those enfolded in living organisms could play a synergic role in modulating biological functions, generating dissipative structures under appropriate patterns of electromagnetic signals providing basis for storing and retrieving biological activities. An external electro-magnetic stimulus from a source molecule can be stored, translated, and transferred by the aqueous systems to the biological target, selectively driving their endogenous activity and mimicking the effect of a source molecule.


Assuntos
Fenômenos Eletromagnéticos , Teoria Quântica , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/efeitos da radiação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/efeitos da radiação , Humanos , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/efeitos da radiação , Tretinoína/farmacologia
4.
Electromagn Biol Med ; 34(2): 167-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26098531

RESUMO

We have performed a series of experiments applying high voltage between two electrodes, immersed in two beakers containing bidistilled water in a way similar to experiments conducted by Fuchs and collaborators, which showed that a water bridge can be formed between the two containers. We also observed the formation of water bridge. Moreover, choosing different pairs of electrodes depending on the material they are made up of, we observed that copper ions flow can pass along the bridge if the negative electrode is made up of copper. We show that the direction of the flux not only depends on the applied electrostatic field but on the relative electronegativity of the electrodes too. These results open new perspectives in understanding the properties of water. We suggest a possible explanation of the obtained results.


Assuntos
Cobre/química , Condutividade Elétrica , Água/química , Eletrodos , Hidrodinâmica
5.
Int J Cardiol ; 370: 122-128, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36328114

RESUMO

AIMS: To identify the best strategy to achieve complete revascularization (CR) in patients with ST-elevation myocardial infarction (STEMI) and multi-vessel disease (MVD). METHODS AND RESULTS: We systematically reviewed the literature for randomized controlled trials (RCTs) comparing IRA-only PCI and CR guided by angiography or fractional flow reserve (FFR) in MVD-STEMI. Both frequentist (classical) and Bayesian network meta-analysis were performed, including a comparative hierarchy estimation of the probability to reduce the primary composite endpoint of all-cause death and new myocardial infarction (MI). We identified 11 RCTs, including 8193 STEMI patients. Compared with IRA-only strategy, CR significantly reduced the primary endpoint (OR: 0.73; 95%CI0.55-0.97). We observed non-significant difference between angiography and FFR guidance in reducing the primary endpoint (OR: 0.73, 95% CI 0.35-1.57). The Bayesian probability analysis ranked angio-guided CR as the best intervention yielding lowest risk of all-cause death or new MI (SUCRA92%). CONCLUSIONS: In patients with MVD-STEMI, CR is associated with a reduction in all-cause mortality and new MI compared with IRA-only PCI. Angio-guided CR is associated with the lowest risk of all-cause death or new MI, therefore the role of FFR-guidance in this setting is questionable. CONDENSED ABSTRACT: Both frequentist and Bayesian network meta-analysis were performed to compare infarct-related artery (IRA)-only percutaneous coronary intervention (PCI) and complete revascularization (CR) guided by angiography or fractional flow reserve (FFR) in multivessel disease (MVD) and acute ST-elevation myocardial infarction (STEMI). Eleven randomized controlled trials were identified, including 8193 STEMI patients. Compared with IRA-only strategy, CR significantly reduced the incidence of the composite endpoint of all-cause death and new myocardial infarction without significant difference in angio-guided and FFR-guided CR. The Bayesian probability analysis ranked angio-guided CR as the best intervention yielding lowest risk of the composite endpoint and, therefore the role of FFR-guidance in this setting is questionable.


Assuntos
Doença da Artéria Coronariana , Reserva Fracionada de Fluxo Miocárdico , Infarto do Miocárdio , Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Humanos , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico por imagem , Infarto do Miocárdio com Supradesnível do Segmento ST/cirurgia , Infarto do Miocárdio com Supradesnível do Segmento ST/etiologia , Angiografia Coronária , Metanálise em Rede , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/cirurgia , Resultado do Tratamento , Intervenção Coronária Percutânea/métodos , Infarto do Miocárdio/etiologia
6.
G Ital Cardiol (Rome) ; 24(4 Suppl 2): 30S-38S, 2023 04.
Artigo em Italiano | MEDLINE | ID: mdl-37158031

RESUMO

BACKGROUND: Over the past decades, the improvements in the diagnostic power and availability of non-invasive cardiac imaging techniques have led to a decline of right heart catheterization (RHC) performance. However, RHC remains the gold standard for diagnosing pulmonary hypertension and an essential tool for the evaluation of patient candidacy to heart transplantation. METHODS: This survey was carried out jointly by the Young Committee of GISE, with the support of the SICI-GISE Society, and the ICOT group, with the aim of evaluating how the interventional cardiology community perform RHC. A web-based questionnaire based on 20 questions was distributed to SICI-GISE members. RESULTS: The survey was distributed to 1550 physicians with 174 (11%) responses. Most centers perform few procedures per year (<10 RHC/year) and a dedicated cardiologist is usually lacking. Patients were frequently admitted as ordinary hospitalization regimen and the most frequent indication for RHC was the hemodynamic assessment of pulmonary hypertension, followed by diagnostics of valvular diseases and advanced heart failure/heart transplantation. Indeed, the majority of participants (86%) are involved in transcatheter procedures for structural heart disease. The average time taken to perform the RHC was approximately 30-60 min. The femoral access (60%) was the most frequently used, usually by an echo-guided approach. Two-thirds of participants discontinued oral anticoagulant therapy before RHC. Only 27% of centers assess wedge position from an integrated analysis. Furthermore, the edge pressure is detected in the end-diastolic cardiac phase in half cases and in the end-expiratory phase in only 31%. The most commonly used method for cardiac output calculation was the indirect Fick method (58%). CONCLUSIONS: Guidance on the best practice for performing RHC is currently lacking. A more precise standardization of this demanding procedure is warranted.


Assuntos
Hipertensão Pulmonar , Humanos , Laboratórios , Cateterismo Cardíaco/métodos , Inquéritos e Questionários , Itália , Anticoagulantes
7.
Cells ; 11(24)2022 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-36552798

RESUMO

Exposure to artificial radio frequency electromagnetic fields (RF-EMFs) has greatly increased in recent years, thus promoting a growing scientific and social interest in deepening the biological impact of EMFs on living organisms. The current legislation governing the exposure to RF-EMFs is based exclusively on their thermal effects, without considering the possible non-thermal adverse health effects from long term exposure to EMFs. In this study we investigated the biological non-thermal effects of low-level indoor exposure to RF-EMFs produced by WiFi wireless technologies, using Drosophila melanogaster as the model system. Flies were exposed to 2.4 GHz radiofrequency in a Transverse Electromagnetic (TEM) cell device to ensure homogenous controlled fields. Signals were continuously monitored during the experiments and regulated at non thermal levels. The results of this study demonstrate that WiFi electromagnetic radiation causes extensive heterochromatin decondensation and thus a general loss of transposable elements epigenetic silencing in both germinal and neural tissues. Moreover, our findings provide evidence that WiFi related radiofrequency electromagnetic fields can induce reactive oxygen species (ROS) accumulation, genomic instability, and behavioural abnormalities. Finally, we demonstrate that WiFi radiation can synergize with RasV12 to drive tumor progression and invasion. All together, these data indicate that radiofrequency radiation emitted from WiFi devices could exert genotoxic effects in Drosophila and set the stage to further explore the biological effects of WiFi electromagnetic radiation on living organisms.


Assuntos
Drosophila melanogaster , Campos Eletromagnéticos , Animais , Campos Eletromagnéticos/efeitos adversos , Drosophila melanogaster/genética , Elementos de DNA Transponíveis/genética , Ondas de Rádio/efeitos adversos , Instabilidade Genômica
8.
Cardiol J ; 28(6): 842-848, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33942280

RESUMO

BACKGROUND: Primary percutaneous coronary intervention (pPCI) in ST-segment elevation myocardial infarction (STEMI) can be challenging for high thrombus burden and catecholamine-induced vasoconstriction. The Xposition-S stent was designed to prevent stent undersizing and minimize strut malapposition. We evaluated 1-year clinical outcomes of a nitinol, self-apposing®, sirolimus-eluting stent, pre-mounted on a novel balloon delivery system, in de novo lesions of patients presenting with STEMI undergoing pPCI. METHODS: The iPOSITION is a prospective, multicenter, post-market, observational study. The primary endpoint, target lesion failure (TLF), was defined as the composite of cardiac death, recurrent target vessel myocardial infarction (TV-MI), and clinically driven target lesion revascularization (TLR). RESULTS: The study enrolled 247 STEMI patients from 7 Italian centers. Both device and procedural success occurred in 99.2% of patients, without any death, TV-MI, TLR, or stent thrombosis during the hospital stay and at 30-day follow-up. At 1 year, TLF occurred in 2.6%, cardiac death occurred in 1.7%, TV-MI occurred in 0.4%, and TLR in 0.4% of patients. The 1-year stent thrombosis rate was 0.4%. CONCLUSIONS: The use of an X-position S self-apposing® stent is feasible in STEMI pPCI, with excellent post-procedural results and 1-year outcomes.


Assuntos
Stents Farmacológicos , Infarto do Miocárdio , Intervenção Coronária Percutânea , Infarto do Miocárdio com Supradesnível do Segmento ST , Trombose , Morte , Humanos , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/métodos , Estudos Prospectivos , Sistema de Registros , Infarto do Miocárdio com Supradesnível do Segmento ST/diagnóstico , Infarto do Miocárdio com Supradesnível do Segmento ST/cirurgia , Stents , Resultado do Tratamento
9.
J Thromb Thrombolysis ; 30(4): 426-33, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20978881

RESUMO

Even though platelet volume has been supposed to be indicator of platelet activation, contrasting results have been reported on its relationship with the extent of coronary artery disease (CAD). No data have been so far reported on Platelet-Large Cell Ratio (P-LCR). Thus, the aim of the current study was to investigate whether P-LCR is associated with CAD. We measured P-LCR in 1882 consecutive patients undergoing coronary angiography. Significant CAD was defined as stenosis >50% in at least 1 coronary vessel. We additionally measured Carotid Intima-Media Thickness (IMT) in 359 patients. The relationship between P-LCR and platelet aggregation was evaluated by PFA-100 and Multiplate. Patients with higher P-LCR were older (P = 0.038), with larger prevalence of diabetes (P < 0.0001), dilated cardiomyopathy or valvular heart disease (P = 0.004) and less often family history of CAD (P = 0.045), more often on statins (P = 0.002), and diuretics (P = 0.016). P-LCR was significantly associated with baseline glycaemia (P = 0.001) and RBC count (P < 0.001), but inversely related to platelet count (P < 0.0001). P-LCR was not associated with the prevalence of CAD (adjusted P = 0.3) or its severity. In addition, P-LCR was not related to Carotid IMT or platelet aggregation in patients with or without aspirin therapy. This study showed that P-LCR is not related to platelet aggregation, aspirin resistance, the extent of CAD and carotid IMT. Thus, P-LCR can not be considered as a marker of platelet reactivity or a risk factor for CAD.


Assuntos
Doença da Artéria Coronariana/sangue , Túnica Íntima/diagnóstico por imagem , Túnica Média/citologia , Túnica Média/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Doença da Artéria Coronariana/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Agregação Plaquetária/fisiologia , Contagem de Plaquetas , Estudos Prospectivos , Túnica Íntima/citologia , Ultrassonografia
10.
G Ital Cardiol (Rome) ; 21(6 Suppl 1): 46S-54S, 2020 06.
Artigo em Italiano | MEDLINE | ID: mdl-32469345

RESUMO

Right heart catheterization (RHC) is a key diagnostic tool in several clinical conditions. It is recognized to be a technically demanding procedure requiring accurate evaluation of results. If performed by skilled operators, RHC provides reliable and valuable measurements with low complication rates. Although increasing data from the literature have become available over time, a comprehensive review of technical details and pitfalls is rare. This article aims to provide an overview of indications and evidence-based practical issues upon RHC to guide interventional cardiologists on how to perform this procedure.


Assuntos
Cateterismo Cardíaco/métodos , Doenças Cardiovasculares/diagnóstico , Cateterismo Cardíaco/efeitos adversos , Cardiologistas , Doenças Cardiovasculares/fisiopatologia , Competência Clínica , Medicina Baseada em Evidências , Humanos
11.
Eur Heart J Case Rep ; 4(5): 1-5, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33204960

RESUMO

BACKGROUND: Selexipag is an oral selective prostacyclin IP receptor agonist approved in patients with low- and intermediate-risk pulmonary hypertension (PH); evidence in patients at high risk is lacking. CASE SUMMARY: A 42-year-old woman with worsening dyspnoea (World Health Organization functional class III-IV) and suspected PH at echocardiographic examination was evaluated in our Pulmonary Hypertension Centre. Right heart catheterization showed pre-capillary PH with reduced cardiac index and increased pulmonary vascular resistance. High-resolution computed tomography excluded parenchymal lung disease and ventilation/perfusion (V/Q) lung scan was negative for mismatched perfusion defects so the conclusive diagnosis was high-risk idiopathic pulmonary arterial hypertension (PAH). The patient refused an initial combination therapy including a parenteral prostacyclin analogue (PCA) in accordance with the ESC/ERS guidelines, so an off-label triple oral combination therapy including a phosphodiesterase-5 inhibitor, an endothelin receptor antagonist, and selexipag was started. At 3- and 6-month follow-up we found a clinical and haemodynamic improvement, so the patient was reclassified as low risk. Her clinical condition is currently stable. DISCUSSION: Despite the benefit of parenteral PCAs in high-risk PAH, low adherence to treatment may be explained by adverse side effects related to the intravenous route of administration. Given the potential effect seen in our patient, upfront triple oral combination therapy in PAH high-risk patients should be further evaluated in a controlled clinical trial.

12.
Basic Clin Pharmacol Toxicol ; 125 Suppl 3: 58-69, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30801980

RESUMO

Epidemiological studies have suggested that human exposure to extremely low-frequency electromagnetic fields from the electric power and to mobile phone radiofrequency electromagnetic fields induce an increased risk of developing malignant tumours. However, no adequate laboratory data, in particular long-term carcinogenicity bioassays to support the epidemiological evidence, have yet been available. This motivated the Ramazzini Institute to embark on a first project of four large life-span carcinogenic bioassays conducted on over 7000 Sprague Dawley rats exposed from prenatal life until natural death to S-50 Hz MF alone or combined with gamma radiation or formaldehyde or aflatoxin B1. Results now available from these studies, which started concurrently, have shown that exposure to Sinusoidal-50 Hz Magnetic Field (S-50 Hz MF) combined with acute exposure to gamma radiation or to chronic administration of formaldehyde in drinking water induces a significantly increased incidence of malignant tumours in males and females. A second project of two large life-span carcinogenic bioassays was conducted on over 3000 Sprague Dawley rats exposed from prenatal life until natural death to 1.8 GHz GSM of mobile phone radio base station, alone or combined with acute exposure to gamma radiation. Early results from the experiment on 1.8 GHz GSM alone show a statistically significant increase in the incidence of heart malignant schwannoma among males exposed at the highest dose.


Assuntos
Carcinogênese/efeitos da radiação , Campos Eletromagnéticos/efeitos adversos , Neoplasias/epidemiologia , Efeitos Tardios da Exposição Pré-Natal/epidemiologia , Radiação não Ionizante/efeitos adversos , Animais , Modelos Animais de Doenças , Exposição Ambiental/efeitos adversos , Feminino , Humanos , Incidência , Neoplasias/etiologia , Neoplasias/prevenção & controle , Gravidez , Efeitos Tardios da Exposição Pré-Natal/etiologia , Efeitos Tardios da Exposição Pré-Natal/prevenção & controle , Ratos Sprague-Dawley
13.
Cardiovasc Revasc Med ; 20(11S): 60-62, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31488363
14.
Electromagn Biol Med ; 27(3): 230-40, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18821199

RESUMO

The specific aim of the present work concerns the effectiveness of low-frequency electromagnetic fields treatment to modify biochemical properties of human keratinocytes (HaCaT). Cells exposed to a 7 Hz electromagnetic field, tuned to calcium ion cyclotron resonance (ICR), showed modifications in the cytoskeleton. These modifications were related to different actin distributions as revealed by phalloidin fluorescence analysis. Indirect immunofluorescence with fluorescent antibodies against involucrin and beta catenin, both differentiation and adhesion markers, revealed an increase in involucrin and beta-catenin expression, indicating that exposure to electromagnetic field carries keratinocytes to an upper differentiation level. This study confirms our previous observation and supports the hypothesis that a 7 Hz calcium ICR electromagnetic field may modify cell biochemistry and interfere in the differentiation and cellular adhesion of normal keratinocytes, suggesting the possibility to use ICR electromagnetic therapy for the treatment of undifferentiated diseases.


Assuntos
Cálcio/metabolismo , Diferenciação Celular/efeitos da radiação , Ciclotrons , Queratinócitos/citologia , Queratinócitos/efeitos da radiação , Actinas/metabolismo , Western Blotting , Terapia por Estimulação Elétrica , Campos Eletromagnéticos , Técnica Indireta de Fluorescência para Anticorpo , Regulação da Expressão Gênica/efeitos da radiação , Humanos , Queratinócitos/metabolismo , Precursores de Proteínas/metabolismo , Reprodutibilidade dos Testes , beta Catenina/metabolismo
15.
Electromagn Biol Med ; 27(2): 127-33, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18568930

RESUMO

The identification of suitable stem cell cultures and differentiating conditions that are free of xenogenic growth supplements is an important step in finding the clinical applicability of cell therapy in two important fields of human medicine: heart failure and bone remodeling, growth and repair. We recently demonstrated the possibility of obtaining cardiac stem cells (CSCs) from human endomyocardial biopsy specimens. CSCs self-assemble into multi-cellular clusters known as cardiospheres (CSps) that engraft and partially regenerate infarcted myocardium. CSps and cardiosphere-derived-cells (CDCs) were exposed for five days in an incubator regulated for temperature, humidity, and CO(2) inside a solenoid system. This system was placed in a magnetically shielded room. The cells were exposed simultaneously to a static magnetic field (MF) and a parallel low-alternating frequency MF, close to the cyclotron frequency corresponding to the charge/mass ratio of the Ca(++) ion. In this exposure condition, CSps and CDCs modulate their differentiation turning on cardiogenesis and turning off vasculogenesis. Cardiac markers such as troponin I (TnI) and myosin heavy chain (MHC) were up-regulated. Conversely, angiogenic markers such as vascular endothelial growth factor (VEGF) and kinase domain receptor (KDR) were down-regulated as evidenced by immunocytochemistry. Exposure to the 7 Hz calcium ion cyclotron resonance (ICR) frequency can modulate the cardiogenic vs. angiogenic differentiation process of ex vivo expanded CSCs. This may pave the way for novel approaches in tissue engineering and cell therapy. With regard to bone remodeling, it has been suggested that bone marrow-derived mesenchymal stem cells (MSC) may be considered as a potential therapeutic tool. Using the Ca(++)-dependent specific differentiation potential of the ELF-MF 7 Hz ICR, we show here that exposure of human MSC to these same MF conditions enhanced the expression of osteoblast differentiation markers such as alkaline phosphatase, osteocalcin, and osteopontin, as analyzed by real-time quantitative PCR, without affecting cell proliferation. As expected, while the differentiation marker factors were up regulated, the ICR electromagnetic field down regulated osteoprotegerin gene expression, a critical regulator of postnatal skeletal development and homeostasis in humans as well as mice.


Assuntos
Técnicas de Cultura de Células/métodos , Diferenciação Celular/efeitos da radiação , Ciclotrons , Medicina Regenerativa/métodos , Células-Tronco/fisiologia , Células-Tronco/efeitos da radiação , Engenharia Tecidual/métodos , Animais , Células Cultivadas , Humanos , Íons , Células-Tronco/citologia
16.
Int J Radiat Biol ; 92(4): 202-14, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26894944

RESUMO

Background In 2002 the International Agency for Research on Cancer classified extremely low frequency magnetic fields (ELFMF) as a possible carcinogen on the basis of epidemiological evidence. Experimental bioassays on rats and mice performed up to now on ELFMF alone or in association with known carcinogens have failed to provide conclusive confirmation. Objectives To study the carcinogenic effects of combined exposure to sinusoidal-50 Hz (S-50 Hz) magnetic fields and acute γ radiation in Sprague-Dawley rats. Methods We studied groups of male and female Sprague-Dawley rats exposed from prenatal life until natural death to 20 or 1000 µT S-50 Hz MF and also to 0.1 Gy γ radiation delivered as a single acute exposure at 6 weeks of age. Results The results of the study showed significant carcinogenic effects for the mammary gland in males and females and a significant increased incidence of malignant schwannomas of the heart as well as increased incidence of lymphomas/leukemias in males. Conclusions These results call for a re-evaluation of the safety of non-ionizing radiation.


Assuntos
Envelhecimento , Carcinogênese/efeitos da radiação , Exposição Ambiental/efeitos adversos , Raios gama/efeitos adversos , Campos Magnéticos/efeitos adversos , Neoplasias Induzidas por Radiação/fisiopatologia , Animais , Relação Dose-Resposta à Radiação , Feminino , Longevidade , Masculino , Neoplasias Induzidas por Radiação/etiologia , Doses de Radiação , Ratos , Ratos Sprague-Dawley , Medição de Risco , Fatores Sexuais , Irradiação Corporal Total/efeitos adversos
18.
Tissue Eng Part C Methods ; 21(2): 207-17, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25087470

RESUMO

In vivo control of osteoblast differentiation is an important process needed to maintain the continuous supply of mature osteoblast cells for growth, repair, and remodeling of bones. The regulation of this process has also an important and significant impact on the clinical strategies and future applications of cell therapy. In this article, we studied the effect of nonpulsed sinusoidal electromagnetic field radiation tuned at calcium-ion cyclotron frequency of 50 Hz exposure treatment for bone differentiation of human mesenchymal stem cells (hMSCs) alone or in synergy with dexamethasone, their canonical chemical differentiation agent. Five days of continuous exposure to calcium-ion cyclotron resonance affect hMSC proliferation, morphology, and cytoskeletal actin reorganization. By quantitative real-time polymerase chain reaction, we also observed an increase of osteoblast differentiation marker expression such as Runx2, alkaline phosphatase (ALP), osteocalcin (OC), and osteopontin (OPN) together with the osteoprotegerin mRNA modulation. Moreover, in these cells, the increase of the protein expression of OPN and ALP was also demonstrated. These results demonstrate bone commitment of hMSCs through a noninvasive and biocompatible differentiating physical agent treatment and highlight possible applications in new regenerative medicine protocols.


Assuntos
Osso e Ossos/patologia , Diferenciação Celular , Campos Eletromagnéticos , Células-Tronco Mesenquimais/citologia , Osteogênese , Cicatrização , Actinas/metabolismo , Fosfatase Alcalina/metabolismo , Biomarcadores/metabolismo , Osso e Ossos/efeitos dos fármacos , Bromodesoxiuridina/metabolismo , Cálcio/farmacologia , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Proliferação de Células/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Ciclotrons , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Células-Tronco Mesenquimais/enzimologia , Células-Tronco Mesenquimais/ultraestrutura , Osteogênese/efeitos dos fármacos , Osteogênese/genética , Osteopontina/metabolismo , Osteoprotegerina/genética , Osteoprotegerina/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Cicatrização/efeitos dos fármacos
19.
PLoS One ; 10(11): e0142259, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26559811

RESUMO

BACKGROUND: Few studies have investigated the toxicity and genotoxicity of extremely low frequency magnetic fields (ELF-MF) during prenatal and neonatal development. These phases of life are characterized by cell proliferation and differentiation, which might make them sensitive to environmental stressors. Although in vitro evidences suggest that ELF-MF may modify the effects of ionizing radiation, no research has been conducted so far in vivo on the genotoxic effects of ELF-MF combined with X-rays. AIM AND METHODS: Aim of this study was to investigate in somatic and germ cells the effects of chronic ELF-MF exposure from mid gestation until weaning, and any possible modulation produced by ELF-MF exposure on ionizing radiation-induced damage. Mice were exposed to 50 Hz, 65 µT magnetic field, 24 hours/day, for a total of 30 days, starting from 12 days post-conception. Another group was irradiated with 1 Gy X-rays immediately before ELF-MF exposure, other groups were only X-irradiated or sham-exposed. Micronucleus test on blood erythrocytes was performed at multiple times from 1 to 140 days after birth. Additionally, 42 days after birth, genotoxic and cytotoxic effects on male germ cells were assessed by comet assay and flow cytometric analysis. RESULTS: ELF-MF exposure had no teratogenic effect and did not affect survival, growth and development. The micronucleus test indicated that ELF-MF induced a slight genotoxic damage only after the maximum exposure time and that this effect faded away in the months following the end of exposure. ELF-MF had no effects on ionizing radiation (IR)-induced genotoxicity in erythrocytes. Differently, ELF-MF appeared to modulate the response of male germ cells to X-rays with an impact on proliferation/differentiation processes. These results point to the importance of tissue specificity and development on the impact of ELF-MF on the early stages of life and indicate the need of further research on the molecular mechanisms underlying ELF-MF biological effects.


Assuntos
Dano ao DNA/efeitos da radiação , Desenvolvimento Embrionário/efeitos da radiação , Campos Magnéticos/efeitos adversos , Efeitos Tardios da Exposição Pré-Natal , Radiação Ionizante , Animais , Diferenciação Celular/efeitos da radiação , Proliferação de Células/efeitos da radiação , Feminino , Células Germinativas/efeitos da radiação , Camundongos , Gravidez
20.
Biochem Pharmacol ; 63(3): 375-80, 2002 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-11853688

RESUMO

Lipoprotein oxidation, which is relevant to atherogenesis, can be induced by redox-active transition metals, such as copper. Vanadium is a metal usually used as vanadyl to improve metabolic control in diabetic patients; given its redox-active properties, we have investigated possible oxidative effects of the metal on lipoproteins from healthy and diabetic subjects. Beginning from 10 microM, vanadyl, but not vanadate, induced oxidation of the non-HDL fraction, which was inhibited by EDTA, butylated hydroxytoluene and Vitamins E and C, but not by mannitol, SOD and catalase. Differently from copper, vanadyl could oxidize directly lipoprotein lipids, although it showed a lower oxidant activity against critical tryptophan residues of the lipoprotein protein moiety. Moreover, the non-HDL fraction of diabetic patients was more susceptible to vanadyl-dependent oxidation than that of controls. Thus, vanadium, in its reduced form which may be used in humans, can oxidize the non-HDL fraction through oxidative effects exerted especially on lipoprotein lipids; the specific pro-oxidant activity of vanadyl is more evident with lipoproteins of diabetic patients. Given also the tissue accumulating capacity of vanadium conceivably in a reduced form, its prolonged administration to humans, especially to diabetic patients without adequate antioxidant supplementation, needs caution.


Assuntos
Apolipoproteínas B/metabolismo , Diabetes Mellitus/metabolismo , Lipoproteínas/metabolismo , Vanadatos/farmacologia , Humanos , Lipoproteínas/efeitos dos fármacos , Oxirredução
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