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1.
Nat Commun ; 14(1): 633, 2023 Feb 06.
Article in English | MEDLINE | ID: mdl-36746941

ABSTRACT

Wireless communications and sensing have notably advanced thanks to the recent developments in both software and hardware. Although various modulation schemes have been proposed to efficiently use the limited frequency resources by exploiting several degrees of freedom, antenna performance is essentially governed by frequency only. Here, we present an antenna design concept based on metasurfaces to manipulate antenna performances in response to the time width of electromagnetic pulses. We numerically and experimentally show that by using a proper set of spatially arranged metasurfaces loaded with lumped circuits, ordinary omnidirectional antennas can be reconfigured by the incident pulse width to exhibit directional characteristics varying over hundreds of milliseconds or billions of cycles, far beyond conventional performance. We demonstrate that the proposed concept can be applied for sensing, selective reception under simultaneous incidence and mutual communications as the first step to expand existing frequency resources based on pulse width.

2.
Rev Recent Clin Trials ; 16(2): 151-165, 2021.
Article in English | MEDLINE | ID: mdl-32735527

ABSTRACT

Backround: Radiation-induced oral mucositis consists of a series of relatively frequent side effects after head and neck cancer radiotherapy and has an adverse impact on both regular treatment process and the quality of life of patients. OBJECTIVE: The purpose of the present review is to optimize the current management of radiation-induced oral mucositis in head and neck cancer patients. METHODS: PubMed database research was performed on articles published since 2015 that demonstrated efficacy in the management of radiation-induced oral mucositis in head and neck cancer patients. The study selection included observational, prospective, comparative, randomized, double- blind, placebo-controlled or uncontrolled, and retrospective studies, as well as systematic reviews and metanalyses. RESULTS: From the 931 citations obtained from the search, only 94 articles met the inclusion criteria, including mucosal protectants, anti-inflammatory agents, growth factors, and various miscellaneous and natural agents. Several methods, including both pharmacological and natural agents, have been proposed for the management of oral mucositis. In addition to the already known interventions with strong evidence, according to the Multinational Association of Supportive Care in Cancer and he International Society of Oral Oncology guidelines, further agents have been used. However, a great number of them lack clear evidence, which surely requires the design of more controlled clinical trials for a better assessment of the ideal methods. CONCLUSION: The management of oral mucositis constitutes an active area of research. In light of these results, it is aimed to illustrate those treatment strategies that are most effective regarding the treatment approach of oral mucositis.


Subject(s)
Head and Neck Neoplasms , Stomatitis , Head and Neck Neoplasms/radiotherapy , Humans , Male , Prospective Studies , Quality of Life , Retrospective Studies , Stomatitis/etiology , Stomatitis/therapy
3.
Front Oncol ; 10: 575148, 2020.
Article in English | MEDLINE | ID: mdl-33330049

ABSTRACT

INTRODUCTION: Pandemic COVID-19 is an unexpected challenge for the oncological community, indicating potential detrimental effects on cancer patients. Our aim was to summarize the converging key points providing a general guidance in order to support decision making, pertaining to the oncologic care in the middle of a global outbreak. METHODS: We did an international online search in twenty five countries that have managed a surge in cancer patient numbers. We collected the recommendations from thirty one medical oncology societies. RESULTS: By synthesizing guidelines for a) oncology service delivery adjustments, b) general and specific treatment adaptations, and c) discrepancies from guidelines comparison, we present a clinical synopsis with the forty more crucial statements. A Covid-19 risk stratification base was also created in order to obtain a quick, objective patient assessment and a risk-benefit evaluation on a case-by-case basis. CONCLUSIONS: In an attempt to face these complex needs and due to limited understanding of COVID-19, a variability of recommendations based on general epidemiological and infectious disease principles rather than definite cancer-related evidence has evolved. Additionally, the absence of an effective treatment or vaccine requires the development of cancer management guidance, capitalizing on comprehensive COVID-19 oncology experience globally.

4.
Indian J Palliat Care ; 26(3): 348-351, 2020.
Article in English | MEDLINE | ID: mdl-33311878

ABSTRACT

AIM: The malignant psoas syndrome (MPS) is a rare and complex cancer-related clinical entity, with a significant impact on cancer patients' quality of life. The literature describing malignant infiltration of the psoas muscle as well as its management is limited. The primary endpoint of the study was the assessment of pain relief in symptomatic terminal-stage MPS patients. MATERIALS AND METHODS: Patients underwent hypofractionated (two- or three-dimensional conformal) radiotherapy as palliative treatment. A dose of 42.5 Gy in 17 daily fractions (2.5 Gy/fraction) was prescribed. Pain response was measured before 3 and 6 months after radiation delivery. RESULTS: Between May 1992 and April 2019, eight patients were treated. The median age was 75 years (range: 59-87 years). All patients had distant metastatic disease at the time of treatment. We found a significant pain relief (median duration of response of 105 days) and an improvement in health-related quality of life. CONCLUSIONS: Radiotherapy had a favorable outcome and can be considered an effective analgesic treatment in case of painful MPS.

5.
Rev Recent Clin Trials ; 15(4): 360-369, 2020.
Article in English | MEDLINE | ID: mdl-32646360

ABSTRACT

Backround: Oral mucositis (OM) consists of a major side effect of radiotherapy (RT) in head and neck (H-N) cancer patients and natural honey is gaining more and more scientific interest due to its beneficial effects in tissue repair. OBJECTIVE: The aim of this review is to better clarify the preventive/therapeutic role of honey in the management of OM in patients with H-N cancer undergoing RT with or without chemotherapy (CT). METHODS: We used the PubMed database to retrieve journal articles and the inclusion criteria were only reviews and meta-analyses that illustrated the effective use of honey for either the prevention or treatment of OM in H-N cancer patients receiving either RT alone or in combination with CT. RESULTS: Our search resulted in 92 citations, of which 12 eventually fulfilled the inclusion criteria of our study. Decreased incidence and severity of OM, extended time of occurrence of mucositis, less weight loss and less treatment interruptions were occasionally documented with conventional honey use in the included reviews and meta-analyses. In contrast to conventional honey, manuka honey proved to be weak in improving OM management in the small number of included reviews in our search. CONCLUSION: Conventional honey might constitute a highly promising natural product against OM attracting much scientific interest due to its easy accessibility and low financial cost. Hence, the lack of studies with high evidence requires further advanced research to enhance the existing knowledge about the potential value of honey in radiation-induced OM in H-N cancer patients.


Subject(s)
Head and Neck Neoplasms , Honey , Radiation Injuries , Stomatitis , Head and Neck Neoplasms/radiotherapy , Humans , Radiation Injuries/prevention & control , Stomatitis/etiology , Stomatitis/prevention & control , Systematic Reviews as Topic
7.
Thromb Haemost ; 117(3): 457-470, 2017 02 28.
Article in English | MEDLINE | ID: mdl-28004059

ABSTRACT

Antithrombotic medications reduce thrombosis but increase bleeding. Identification of ST-elevation myocardial infarction (STEMI) patients at risk of recurrent thrombosis could allow targeted treatment with potent antithrombotic medications, with less potent agents in others, to reduce bleeding. Conventional platelet function tests assess platelet reactivity only, yet there is increasing evidence that endogenous thrombolytic potential determines outcome following thrombus initiation. We investigated whether assessing both platelet reactivity and endogenous thrombolysis, could identify STEMI patients at high-risk of recurrent thrombotic events. Thrombotic status was assessed in STEMI patients, before and after primary percutaneous coronary intervention (PPCI), at discharge and at 30 days; with 12 months' follow-up. The time to form an occlusive thrombus under high shear (occlusion time, OT), and time to restore flow by endogenous thrombolysis (lysis time, LT) was measured using the point-of-care Global Thrombosis Test (GTT) in the cardiac catheterisation laboratory. Impaired endogenous thrombolysis (prolonged LT ≥ 3000 s), seen in 13 % patients pre-PPCI, was related to major adverse cardiac events, MACE (HR: 3.31, 95 %CI: 1.02-10.78, p = 0.045), driven by cardiovascular death (HR: 4.17, 95 %CI: 0.99-17.51, p = 0.05). Enhanced (rapid) endogenous thrombolysis (LT < 1000 s) was associated with spontaneous reperfusion, ST-segment resolution and Thrombolysis In Myocardial Infarction 3 flow pre-PPCI. Baseline OT was shorter in those with MACE (especially recurrent myocardial infarction and stroke) than those without (253 ± 150 s vs 354 ± 134 s, p=0.017). Endogenous thrombolysis, when impaired, is associated with increased cardiovascular risk, and when enhanced, with spontaneous reperfusion. Endogenous thrombolysis may be a novel target for pharmacological intervention, and allow targeting of potent antithrombotic medications to high-risk patients.


Subject(s)
Blood Coagulation , Coronary Thrombosis/therapy , Percutaneous Coronary Intervention/adverse effects , Platelet Activation , ST Elevation Myocardial Infarction/therapy , Aged , Area Under Curve , Blood Coagulation Tests , Coronary Thrombosis/blood , Coronary Thrombosis/diagnosis , Female , Humans , Male , Middle Aged , Platelet Function Tests , Point-of-Care Testing , Predictive Value of Tests , Prospective Studies , ROC Curve , Recurrence , Risk Assessment , Risk Factors , ST Elevation Myocardial Infarction/blood , ST Elevation Myocardial Infarction/diagnosis , Time Factors , Treatment Outcome
8.
Oxf Med Case Reports ; 2015(3): 232-4, 2015 Mar.
Article in English | MEDLINE | ID: mdl-27559478

ABSTRACT

Coronary embolism is a well-recognized cause of myocardial infarction. It is often under diagnosed and cardiologists need to be vigilant for this diagnosis. A 77-year-old man presented with chest pain with an ECG showing a new diagnosis of atrial fibrillation. Owing to ongoing chest pain coronary angiography was performed and revealed an acute occlusion of the left circumflex artery with coronary blood flow restored following aspiration of a large red thrombus. Following this the coronary vessel looked smooth with no residual coronary lesions requiring angioplasty or plaque rupture to justify the thrombosis. The clinical picture and angiographic data suggested the coronary embolus was secondary to the newly diagnosed atrial fibrillation.

9.
Eur Heart J ; 34(5): 354-63, 2013 Feb.
Article in English | MEDLINE | ID: mdl-23048192

ABSTRACT

AIMS: End-stage renal disease (ESRD) patients have an excess cardiovascular risk, above that predicted by traditional risk factor models. Prothrombotic status may contribute to this increased risk. Global thrombotic status assessment, including measurement of occlusion time (OT) and thrombolytic status, may identify vulnerable patients. Our aim was to assess overall thrombotic status in ESRD and relate this to cardiovascular risk. METHODS AND RESULTS: Thrombotic and thrombolytic status of ESRD patients (n = 216) on haemodialysis was assessed using the Global Thrombosis Test. This novel, near-patient test measures the time required to form (OT) and time required to lyse (lysis time, LT) an occlusive platelet thrombus. Patients were followed-up for 276 ± 166 days for major adverse cardiovascular events (MACE, composite of cardiovascular death, non-fatal MI, or stroke). Peripheral arterial or arterio-venous fistula thrombosis was a secondary endpoint. Occlusion time was reduced (491 ± 177 vs. 378 ± 96 s, P < 0.001) and endogenous thrombolysis was impaired (LT median 1820 vs.1053 s, P < 0.001) in ESRD compared with normal subjects. LT ≥ 3000 s occurred in 42% of ESRD patients, and none of the controls. Impaired endogenous thrombolysis (LT ≥ 3000 s) was strongly associated MACE (HR = 4.25, 95% CI = 1.58-11.46, P = 0.004), non-fatal MI and stroke (HR = 14.28, 95% CI = 1.86-109.90, P = 0.01), and peripheral thrombosis (HR = 9.08, 95% CI = 2.08-39.75, P = 0.003). No association was found between OT and MACE. CONCLUSION: Impaired endogenous thrombolysis is a novel risk factor in ESRD, strongly associated with cardiovascular events.


Subject(s)
Cardiovascular Diseases/etiology , Kidney Failure, Chronic/complications , Thrombosis/diagnosis , Adolescent , Adult , Aged , Aged, 80 and over , Cause of Death , Female , Fibrin Clot Lysis Time , Humans , Male , Middle Aged , Point-of-Care Systems , ROC Curve , Risk Factors , Young Adult
10.
J Neurooncol ; 106(1): 23-31, 2012 Jan.
Article in English | MEDLINE | ID: mdl-21735116

ABSTRACT

Estrogen receptors alpha (ERα) and beta (ERß) and their co-regulatory proteins are key components of complex signaling networks that specifically regulate the growth and development of various tissues and tumors. Still, their protein expression profiles and possible role in the pathogenesis of astrocytic tumors remain largely unknown. The purpose of the present study is to evaluate the differential protein expression of ΕRα, ERß, and their co-activators, AIB1, TIF2, and PELP1 in astrocytic tumors of World Health Organization (WHO) grade II-IV, using immunohistochemistry. Potential correlations with clinicopathological parameters and patient prognosis were also explored. ERα protein expression was undetectable while ERß levels were significantly decreased with progression of tumor grade (P < 0.001). High expression of ERß was an independent favorable prognostic factor on multivariate analysis (P = 0.003). Expression of AIB1, TIF2, and PELP1 was not correlated with ERß expression and followed an opposite trend, with increasing levels in high-grade relative to low-grade tumors (P < 0.001). Univariate survival analysis revealed that high AIB1, TIF2, and PELP1 expression was associated with worse prognosis (P = 0.049, P = 0.033, and P = 0.020, respectively). ERß and ER co-activators AIB1, TIF2, and PELP1 appear to play an important role in the pathogenesis and progression of astrocytic tumors and might have prognostic significance. The mechanisms underlying their involvement in astrocytic tumorigenesis, as well as their utility for prognostic and therapeutic purposes merit further investigation.


Subject(s)
Astrocytoma/metabolism , Biomarkers, Tumor/analysis , Brain Neoplasms/metabolism , Co-Repressor Proteins/analysis , Nuclear Receptor Coactivator 2/analysis , Nuclear Receptor Coactivator 3/analysis , Transcription Factors/analysis , Adult , Analysis of Variance , Astrocytoma/diagnosis , Astrocytoma/pathology , Brain Neoplasms/diagnosis , Brain Neoplasms/pathology , Estrogen Receptor beta/metabolism , Female , Humans , Immunohistochemistry , Kaplan-Meier Estimate , Male , Middle Aged , Neoplasm Proteins/biosynthesis , Neoplasm Proteins/genetics , Paraffin Embedding , Prognosis , Survival Analysis , Tissue Fixation
11.
Opt Express ; 18(21): 22187-98, 2010 Oct 11.
Article in English | MEDLINE | ID: mdl-20941120

ABSTRACT

This paper shows that customised broadband absorption of electromagnetic waves having arbitrary polarisation is possible by use of lossy cut-wire (CW) metamaterials. These useful features are confirmed by numerical simulations in which different lengths of CW pairs are combined as one periodic metamaterial unit and placed near to a perfect electric conductor (PEC). So far metamaterial absorbers have exhibited some interesting features, which are not available from conventional absorbers, e.g. straightforward adjustment of electromagnetic properties and size reduction. The paper shows how with proper design a broad range of absorber characteristics may be obtained.


Subject(s)
Optics and Photonics , Absorption , Algorithms , Computer Simulation , Electric Conductivity , Materials Testing , Metals/chemistry , Radiation
12.
J Am Coll Cardiol ; 55(19): 2107-15, 2010 May 11.
Article in English | MEDLINE | ID: mdl-20447533

ABSTRACT

OBJECTIVES: Our objective was to assess endogenous thrombolytic activity in acute coronary syndrome (ACS) patients and relate this to their likelihood of future adverse cardiovascular events. BACKGROUND: Spontaneous lysis of platelet-rich thrombi is an important defense mechanism against lasting occlusion. Despite convincing evidence for the role of endogenous fibrinolysis in ACS, the prognostic value of plasma fibrinolytic markers in assessing risk is limited. We employed a novel global test which, in addition to platelet reactivity, allows assessment of endogenous thrombolytic activity to identify ACS patients who remain at risk of cardiovascular events. METHODS: We used the global thrombosis test (GTT) to assess thrombotic and thrombolytic status in 300 ACS patients receiving dual-antiplatelet therapy. The test assesses the time required to form an occlusive thrombus, the occlusion time (OT), and the time to lyse this, the lysis time (LT). The end point of the study at 12 months' follow-up was the composite of death, nonfatal myocardial infarction, or stroke. RESULTS: The OT and LT were both prolonged in ACS patients compared with normal volunteers (p < 0.001). LT > or =3,000 s occurred in 23% of ACS patients versus none of the normal subjects and was a significant and independent predictor of cardiovascular death and nonfatal myocardial infarction in a multivariate model adjusted for cardiovascular risk factors. LT > or =3,000 s was the optimal cutoff value for predicting 12-month major adverse cardiovascular events (hazard ratio [HR]: 2.52, 95% confidence interval: 1.34 to 4.71, p = 0.004) and cardiovascular death (HR: 4.2, 95% confidence interval: 1.13 to 15.62, p = 0.033). HR increased further as LT increased. No association was found between OT and the risk of major adverse cardiovascular events. CONCLUSIONS: Assessment of endogenous thrombolytic status based on the lysis of platelet-rich thrombi from native blood using the point-of-care GTT can identify ACS patients at risk of future cardiac events.


Subject(s)
Acute Coronary Syndrome/blood , Blood Coagulation Tests/methods , Fibrinolysis/physiology , Myocardial Infarction/blood , Thrombosis/blood , Acute Coronary Syndrome/complications , Acute Coronary Syndrome/mortality , Adult , Aged , Aged, 80 and over , Biomarkers/blood , Cohort Studies , Humans , Male , Middle Aged , Myocardial Infarction/etiology , Myocardial Infarction/mortality , Platelet Aggregation Inhibitors/therapeutic use , Predictive Value of Tests , Prognosis , Thrombosis/diagnosis , Thrombosis/drug therapy
13.
Expert Rev Med Devices ; 7(3): 381-8, 2010 May.
Article in English | MEDLINE | ID: mdl-20420559

ABSTRACT

Percutaneous coronary intervention has revolutionized coronary revascularization therapy. It is increasingly becoming an attractive alternative to medical therapy and surgical revascularization in the treatment of coronary artery disease. Restenosis is a major challenge, and has been described as the Achilles heel of the procedure. It is a serious occurrence that can lead not only to recurrent angina and repeat revascularization, but also to acute coronary syndromes. Newer devices and strategies are being continuously sought to try and overcome these hurdles. Drug-eluting balloon technology is one such device that can potentially provide the solutions to these problems. This review focuses on the limitations associated with the use of drug-eluting stents in treating in-stent restenosis, and the concept and the available evidence for the use of drug-eluting balloons, particularly the paclitaxel-eluting balloons, in coronary and peripheral revascularization.


Subject(s)
Catheterization/instrumentation , Coronary Restenosis/therapy , Drug-Eluting Stents , Animals , Anti-Inflammatory Agents/therapeutic use , Clinical Trials as Topic , Coronary Restenosis/drug therapy , Humans
15.
Int J Radiat Oncol Biol Phys ; 67(1): 264-72, 2007 Jan 01.
Article in English | MEDLINE | ID: mdl-17084550

ABSTRACT

PURPOSE: Ibandronate is a single-nitrogen, noncyclic bisphosphonate with proven efficacy for reducing metastatic bone pain. In this study, we assessed the palliative effects of combined ibandronate and radiotherapy. METHODS AND MATERIALS: Forty-five patients with bone metastases from various solid tumors received external-beam radiotherapy, 30-40 Gy over 3-4.5, weeks combined with 10 cycles of monthly intravenous ibandronate, 6 mg. RESULTS: After combined therapy, mean bone pain scores (graded from 0 to 10) were reduced from 6.3 at baseline to 0.8 after 3 months, with further reductions at later time points (all p < 0.001). Opioid use decreased from 84% of patients at baseline (38/45) to 24% (11/45) at 3 months, with further subsequent reductions (all p < 0.001). Mean performance status and functioning scores also significantly improved. Bone density (assessed by computed tomography scan) increased by 20% vs. baseline at 3 months, 46% at 6 months, and 73% at 10 months (all p < 0.001). Lesion improvement was also demonstrated by magnetic resonance imaging. Treatment was well tolerated with no renal toxicity. CONCLUSIONS: In this pilot study, combined radiotherapy and ibandronate provided substantial bone pain relief and increased bone density. Computed tomography-based or magnetic resonance imaging-based evaluations offer objective methods for assessing therapeutic outcomes.


Subject(s)
Bone Density Conservation Agents/therapeutic use , Bone Neoplasms , Diphosphonates/therapeutic use , Pain/drug therapy , Pain/radiotherapy , Aged , Analgesics, Opioid/therapeutic use , Bone Density Conservation Agents/adverse effects , Bone Diseases/drug therapy , Bone Diseases/radiotherapy , Bone Neoplasms/drug therapy , Bone Neoplasms/radiotherapy , Bone Neoplasms/secondary , Combined Modality Therapy/methods , Diphosphonates/adverse effects , Female , Humans , Ibandronic Acid , Infusions, Intravenous , Magnetic Resonance Imaging , Male , Middle Aged , Pain Measurement , Pilot Projects , Prospective Studies , Statistics, Nonparametric
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