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AIMS: The National Palliative Care and Interventional Radiotherapy Study Groups of the Italian Association of Radiotherapy and Clinical Oncology (AIRO) carried out a survey whose aim was to obtain a "snapshot" of the real-world practice of nonmelanoma skin cancer (NMSC) treatments in Italy. MATERIALS AND METHODS: The survey was conducted on SurveyMonkey's online interface and was sent via e-mail to our society Radiation Oncologists. RESULTS: Fifty-eight Italian radiation oncologists (ROs), representing 54 centers, answered the survey. Thirteen percent of the ROs declared they treat fewer than 10 NMSC lesions annually, 36% treat between 11 and 20, and 51% treat more than 20 lesions annually. Interventional radiotherapy (IRT) was offered by 25% of the ROs, and every case was reportedly discussed by a multidisciplinary team (71%). Electrons (74%), volumetric modulated arc therapy (V-MAT) (57%), three-dimensional conformal radiotherapy (3D-CRT) (43%), and IRT (26%) were the main treatment options. With external beam radiotherapy (EBRT), 46 and 53 different RT schedules were treated for curative and palliative intent, respectively; whereas for IRT, there were 21 and 7 for curative and palliative intent, respectively. The most popular EBRT curative options were 50-70.95/22-35 fractions (fx) and 50-70 Gy/16-20fx and for EBRT palliative settings, 30Gy/10fx, and 20-35Gy/5fx. For IRT, the most popular curative options were 32-50Gy/8-10fx and 30-54Gy/3-5fx, whereas 30Gy/6fz was the palliative option. Less than 10 re-RT cases were reported in one year in 42.5%, 11-20 cases in 42.5%, and >20 cases annually in 15%. Electrons (61%), VMAT (49%), and BRT (25%) were the most widely used approaches: 20-40Gy in 10fx and 20-25Gy in 5fx were the recommended fractionations. CONCLUSION: The survey shows a variegated reality. A national registry with more detailed data could help in undercover its causes.
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BACKGROUND: Oligometastases in mediastinal nodes are increasingly prevalent, posing challenges for treatment with stereotactic body radiotherapy (SBRT) due to proximity to organs at risk (OARs). We report the results of a single prospective observational phase II trial on ablative SBRT for medically inoperable thoracic nodes metastases (NCT02970955). MATERIAL AND METHODS: Since 2017, patients with < 3 nodal metastases were evaluated by the tumor board and included if deemed inoperable. SBRT was delivered using risk adaptive approach based on number, site and size of metastatic nodes (50 Gy/5fractions, 60 Gy/8fractions, 70 Gy/10 fractions). Planning target volume (PTV) partial underdosage was allowed. The primary end point was local control (LC) at 12 months. Secondary end points were: acute and late toxicities, overall survival (OS), progression free survival (PFS), and time to next systemic therapy (TTNS). RESULTS: Between 03/2017-11/2021, 32 patients (41 nodal metastases) were included. NSCLC (13pts), breast (5pts) and colorectal cancer (4pts) were the most represented primary tumour. In 66 % cases, partial PTV undercoverage was necessary. LC at 1 and 2 years was 93.5 % and 82.3 %, respectively. Treatment was well-tolerated with no acute or late toxicity ≥ G3. Median OS was 59.7 months. OS at 1 and 2 years was 96.9 % and 83.8 % respectively. Median PFS was 12.2 months. PFS at 1 and 2 years was 53.1 % and 31.3 %, respectively. CONCLUSION: This trial supported the feasibility and safety of ablative SBRT for thoracic nodes metastases thanks to risk adaptive approach allowing to delay of new systemic therapies. Larger studies are needed to confirm these observations.
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Metástasis Linfática , Radiocirugia , Humanos , Radiocirugia/métodos , Radiocirugia/efectos adversos , Femenino , Estudios Prospectivos , Masculino , Anciano , Persona de Mediana Edad , Anciano de 80 o más Años , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/mortalidad , Adulto , Carcinoma de Pulmón de Células no Pequeñas/radioterapia , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Neoplasias de la Mama/patología , Neoplasias de la Mama/radioterapia , Neoplasias de la Mama/mortalidad , Neoplasias Colorrectales/patologíaRESUMEN
BACKGROUND AND PURPOSE: To report mature results for local control and survival in oligometastatic (OM) breast cancer patients treated with stereotactic body radiotherapy (SBRT) on lung and/or liver lesions in a phase II trial. METHODS: This is a prospective non-randomized phase II trial (NCT02581670) which enrolled patients from 2015 to 2021. Eligibility criteria included: age > 18 years, ECOG 0-2, diagnosis of breast cancer, maximum of 4 lung/liver lesions (with a maximum diameter < 5 cm), metastatic disease confined to the lungs and liver or extrapulmonary or extrahepatic disease stable or responding to systemic therapy. The primary end-points were local control (LC) and treatment-related toxicities. The secondary end-points included overall survival (OS), distant metastasis-free survival (DMFS), time to next systemic therapy (TTNS), poly-progression free survival (PPFS). RESULTS: The study included 64 patients with a total of 90 lesions treated with SBRT. LC at 1 and 2 years was 94.9 %, 91 % at 3 years. Median local control was not reached. Median OS was 16.5 months, OS at 1, 2 and 3 years was 87.5 %, 60.9 % and 51.9 %, respectively. Median DMFS was 8.3 months, DMFS at 1, 2 and 3 years was 38.1 %, 20.6 % and 16 % respectively. At univariate analysis, local response to SBRT was found to be statistically linked with better OS, DMFS and STFS. CONCLUSION: SBRT is a safe and valid option in oligometastatic breast cancer patients, with very high rates of local control. An optimal selection of patients is likely needed to improve survival outcomes and reduce the rate of distant progression.
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Neoplasias de la Mama , Neoplasias Hepáticas , Neoplasias Pulmonares , Radiocirugia , Humanos , Femenino , Neoplasias de la Mama/patología , Neoplasias de la Mama/radioterapia , Neoplasias de la Mama/mortalidad , Radiocirugia/métodos , Neoplasias Hepáticas/secundario , Neoplasias Hepáticas/radioterapia , Neoplasias Hepáticas/mortalidad , Neoplasias Hepáticas/cirugía , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/mortalidad , Persona de Mediana Edad , Estudios Prospectivos , Anciano , Adulto , Anciano de 80 o más AñosRESUMEN
Therapeutical strategies in breast cancer are continuously updating. Recent researches assessed the possibility of irradiating only the surgical bed in selected patients (Partial Breast Irradiation, PBI). In 2014 we designed a study to evaluate toxicity and cosmesis of APBI using Volumetric Modulated Arc Therapy-Rapid Arc compared with hypofractionated whole breast irradiation (WBI). We present here the 5-years updated data. HYPAB was a single-institution randomized trial that recruited 172 patients from 2015 to 2018. Patients underwent conserving surgery and were randomized to either adjuvant WBI (40.5Gy/15 fractions with simultaneous boost to 48 Gy to tumoral bed) or APBI (30Gy/5 fractions), both delivered with VMAT-RA technique. Clinical evaluation was performed during the first visit, once a week during radiotherapy and during follow up. Cosmesis was assessed using the Harvard Scale for Breast Cosmesis. At the time of the analysis 161 patients were eligible, 53% in the WBI and 47% in the APBI group, with a median follow-up of 67 months. Most common late skin toxicities were G1 fibrosis (32%) and oedema (28%) and were higher in the WBI group; no G3 toxicities were observed. Cosmesis was rated poor in only 6 cases. 147 patients had no evidence of disease at the last follow-up, and no patients died of the disease. Mature results confirm the safety and efficacy of APBI in selected early stage breast cancer patients. Late toxicity is improved in the APBI arm at the cost of a slight increase in local relapse. Further studies are ongoing to better elucidate the use of APBI as a de-escalation approach.
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Neoplasias de la Mama , Femenino , Humanos , Neoplasias de la Mama/radioterapia , Neoplasias de la Mama/cirugía , Posmenopausia , Mastectomía Segmentaria , Recurrencia Local de Neoplasia/epidemiología , Recurrencia Local de Neoplasia/prevención & control , Recurrencia Local de Neoplasia/cirugía , Mama/efectos de la radiaciónRESUMEN
A Correction to this paper has been published: https://doi.org/10.1007/s00248-021-01811-x.
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PURPOSE: to report toxicity and cosmetic outcome with a median follow-up of 6 years of a phase II trial of hypofractionated radiotherapy with volumetric modulated arc therapy (VMAT) and simultaneous integrated boost (SIB) for early-stage breast cancer after conservative surgery. MATERIALS AND METHODS: From August 2010 to September 2014, patients requiring adjuvant radiotherapy for early-stage breast cancer were treated according to a phase I-II protocol with SIB to 40.5 and 48 Gy to the breast and the boost region, respectively, with VMAT technique. The primary endpoint evaluated the treatment feasibility regarding adherence to required dose constraints for target, heart and lungs. Acute and late toxicity, local and distant control were secondary endpoints. RESULTS: 450 patients were included in the trial and analysed after a median follow-up of 6 years. Acute toxicity was already presented in a previous paper. Regarding late toxicity, 93% of patients had no skin alteration at five years, while 5.3% and 1.3% did record G1 and G2 residual toxicity, respectively. Cosmetic outcome was scored good or excellent in almost all cases (97.2%), fair only in 2.3% of patients. Residual tenderness in the irradiated breast was reported by 10% of patients. Cosmesis and breast pain improved during follow-up. Two cases of G2 pneumonitis and two cases of ischemic cardiopathy were registered during follow-up. Five cases presented local recurrence in the homolateral breast, four patients had a new primary cancer in the contralateral breast, while distant metastasis developed in 7 patients. CONCLUSION: After more than six years, hypofractionated VMAT with SIB for adjuvant radiotherapy in early-stage breast cancer patients remains a safe and effective approach. Mature data on skin toxicity and cosmetic outcome are encouraging. However, longer follow-up is required to evaluate local control, cardiac toxicity and secondary carcinogenesis.
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Neoplasias de la Mama , Radioterapia de Intensidad Modulada , Mama , Neoplasias de la Mama/radioterapia , Neoplasias de la Mama/cirugía , Femenino , Humanos , Mastectomía Segmentaria , Hipofraccionamiento de la Dosis de Radiación , Radioterapia Adyuvante/efectos adversos , Radioterapia de Intensidad Modulada/efectos adversosRESUMEN
Exciton-polaritons are hybrid light-matter excitations arising from the nonperturbative coupling of a photonic mode and an excitonic resonance. Behaving as interacting photons, they show optical third-order nonlinearities providing effects such as optical parametric oscillation or amplification. It has been suggested that polariton-polariton interactions can be greatly enhanced by inducing aligned electric dipoles in their excitonic part. However, direct evidence of a true particle-particle interaction, such as superfluidity or parametric scattering, is still missing. In this Letter, we demonstrate that dipolar interactions can be used to enhance parametric effects such as self-phase modulation in waveguide polaritons. By quantifying these optical nonlinearities, we provide a reliable experimental measurement of the direct dipolar enhancement of polariton-polariton interactions.
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OBJECTIVE: Since the beginning of the COVID-19 pandemic it has been recommended that chemical disinfectants are used to protect surfaces. This study aimed to determine whether the number of exposure calls related to household disinfectants (HD) received between January 30, 2020 to May 18, 2020 varied from the same time period in the previous year. MATERIALS AND METHODS: A retrospective review of the poison control center database from the Fondazione Universitario Policlinico Agostino Gemelli IRCCS, Rome, Italy, was conducted. Calls from Italian citizens, hospitals, and general practitioners received during the same time period in 2019 and 2020 were compared. RESULTS: The center received 1972 exposure calls during the study period. A 5% increase in calls regarding exposure to HDs was noted from 2019 to 2020 (9.8% to 15.2%, p<0.001). The majority of enquiries regarded bleach-containing products, hand sanitizers, ethanol, and hydrogen peroxide. Most calls were received from patients in their homes (n, 259; prevalence, 86%; increase, 107%) and concerned accidental exposure (n, 280; prevalence, 93%; increase, 76%), while cases of intentional exposure decreased (n, 14; prevalence, 5%; decrease, 33%). The main route of exposure was ingestion (n, 170; prevalence, 57%; increase, 45%), but the highest increase was observed in inhalation cases (n, 82; prevalence, 27%; increase, 122%). CONCLUSIONS: As the incidence of enquiries regarding products that can represent an important health hazard, when improperly used, increased in 2020 suggests that the COVID-19 public health messaging on the proper use of HDs should be improved.
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COVID-19/prevención & control , Desinfectantes/envenenamiento , Desinfección , Vivienda/normas , Centros de Control de Intoxicaciones/estadística & datos numéricos , SARS-CoV-2 , COVID-19/transmisión , Humanos , Italia , Estudios Retrospectivos , SARS-CoV-2/efectos de los fármacosRESUMEN
Results: Road tunnel construction workers revealed higher frequencies of cells with genotoxic damage (i.e., MN and NBUD). MN and NBUD resulted to be Poisson distributed and counts of these genotoxicity biomarkers were then analysed by Poisson regression. The frequency ratio (FR) for MN was 1.31 (95% CI: 0.84-2.04), with an increase in the exposed subjects; this finding, though indicating a higher genotoxic risk in the exposed subjects, did not reach statistical significance. On the other hand, the FR for NBUD was 3.49 (95% CI: 1.86-6.56), with a statistically significant increased risk of chromosomal damage. Even the frequencies of binucleated cells (a marker of cell proliferation) and pyknotic cells (a cell death biomarker) were significantly higher in tunnel workers. Introduction: Tunnel construction workers are exposed to complex mixtures of toxic agents, some of which are known to be genotoxic. The aim of this study was to evaluate the genotoxic risk in this occupational setting by comparing tunnel workers with a control group for frequencies of nuclear aberrations in oral exfoliated cells. Methods: To evaluate the genotoxic effects of tunnel air pollutants, we conducted a cross-sectional, molecular epidemiological study (35 tunnel workers and 35 healthy controls) using the buccal micronucleus cytome assay. A questionnaire was administered to obtain information about demographic variables, lifestyle, dietary habits, anthropometric data, and occupational history. Buccal mucosa cells were collected by scraping the buccal mucosa with a small-headed toothbrush. Coded slides were examined blind by trained scorers for micronuclei (MN), nuclear buds (NBUD), and other nuclear abnormalities. Conclusions: Our observations provide further knowledge and understanding of the occupational hazards of tunnel workers and confirm the complexity of effects (cytotoxic and genotoxic) probably induced by fumes and dust produced in underground operations.
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Monitoreo Biológico , Exposición Profesional , Estudios Transversales , Análisis Citogenético , Daño del ADN , Humanos , Pruebas de Micronúcleos , Exposición Profesional/efectos adversosRESUMEN
Topological physics relies on the structure of the eigenstates of the Hamiltonians. The geometry of the eigenstates is encoded in the quantum geometric tensor1-comprising the Berry curvature2 (crucial for topological matter)3 and the quantum metric4, which defines the distance between the eigenstates. Knowledge of the quantum metric is essential for understanding many phenomena, such as superfluidity in flat bands5, orbital magnetic susceptibility6,7, the exciton Lamb shift8 and the non-adiabatic anomalous Hall effect6,9. However, the quantum geometry of energy bands has not been measured. Here we report the direct measurement of both the Berry curvature and the quantum metric in a two-dimensional continuous medium-a high-finesse planar microcavity10-together with the related anomalous Hall drift. The microcavity hosts strongly coupled exciton-photon modes (exciton polaritons) that are subject to photonic spin-orbit coupling11 from which Dirac cones emerge12, and to exciton Zeeman splitting, breaking time-reversal symmetry. The monopolar and half-skyrmion pseudospin textures are measured using polarization-resolved photoluminescence. The associated quantum geometry of the bands is extracted, enabling prediction of the anomalous Hall drift, which we measure independently using high-resolution spatially resolved epifluorescence. Our results unveil the intrinsic chirality of photonic modes, the cornerstone of topological photonics13-15. These results also experimentally validate the semiclassical description of wavepacket motion in geometrically non-trivial bands9,16. The use of exciton polaritons (interacting photons) opens up possibilities for future studies of quantum fluid physics in topological systems.
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Polaritonic devices exploit the coherent coupling between excitonic and photonic degrees of freedom to perform highly nonlinear operations with low input powers. Most of the current results exploit excitons in epitaxially grown quantum wells and require low-temperature operation, while viable alternatives have yet to be found at room temperature. We show that large single-crystal flakes of two-dimensional layered perovskite are able to sustain strong polariton nonlinearities at room temperature without the need to be embedded in an optical cavity formed by highly reflecting mirrors. In particular, exciton-exciton interaction energies are shown to be spin dependent, remarkably similar to the ones known for inorganic quantum wells at cryogenic temperatures, and more than one order of magnitude larger than alternative room temperature polariton devices reported so far. Because of their easy fabrication, large dipolar oscillator strengths, and strong nonlinearities, these materials pave the way for realization of polariton devices at room temperature.
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BACKGROUND: Stereotactic body radiotherapy (SBRT) is characterized by the delivery of high doses of ionizing radiation in few fractions. It is highly effective in achieving local control, and, due to the high biological effective dose administered, it seems to overcome the radioresistance of renal cell carcinoma (RCC). Thus, SBRT could constitute a treatment option for the management of localized RCC in patients who are not surgical candidates. In this paper, we report an overview about data from the current evidence about SBRT in patients affected by localized RCC. MATERIALS AND METHODS: A non-systematic review was performed, including data from both retrospective and prospective studies focusing on the use of SBRT for localized RCC and its biological rationale. Furthermore, ongoing trials on this issue are reported. CONCLUSION: Currently, SBRT might be considered a treatment alternative in inoperable patients affected by primary RCC. Currently, dose-escalation to 48 Gy in 3-4 fractions are effective and well tolerated. Emerging role of immune therapies in RCC patients warrant further studies to explore interactions between SBRT and immune response.
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Carcinoma de Células Renales/cirugía , Neoplasias Renales/cirugía , Radiocirugia/instrumentación , Radiocirugia/métodos , Carcinoma de Células Renales/patología , Humanos , Neoplasias Renales/patología , PronósticoRESUMEN
Microcavity polaritons are two-dimensional bosonic fluids with strong nonlinearities, composed of coupled photonic and electronic excitations. In their condensed form, they display quantum hydrodynamic features similar to atomic Bose-Einstein condensates, such as long-range coherence, superfluidity and quantized vorticity. Here we report the unique phenomenology that is observed when a pulse of light impacts the polariton vacuum: the fluid which is suddenly created does not splash but instead coheres into a very bright spot. The real-space collapse into a sharp peak is at odd with the repulsive interactions of polaritons and their positive mass, suggesting that an unconventional mechanism is at play. Our modelling devises a possible explanation in the self-trapping due to a local heating of the crystal lattice, that can be described as a collective polaron formed by a polariton condensate. These observations hint at the polariton fluid dynamics in conditions of extreme intensities and ultrafast times.
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Urban air contains many mutagenic pollutants. This research aimed to investigate the presence of mutagens in the air by short-term mutagenicity tests using bacteria, human cells and plants. Inflorescences of Tradescantia were exposed to air in situ for 6h, once a month from January to May, to monitor volatile compounds and micronuclei frequency was computed. On the same days PM10 was collected continuously for 24h. Half of each filter was extracted with organic solvents and studied by means of the Ames test, using Salmonella typhimurium TA98 and TA100 strains, and the comet assay on human leukocytes. A quarter of each filter was extracted with distilled water in which Tradescantia was exposed. PM10 concentration was particularly high in the winter season (> 50 µg/m(3)). In situ exposure of inflorescences to urban air induced a significant increase in micronuclei frequency at all the sites considered, but only in January (p < 0.01). Aqueous extracts collected in January and February induced genotoxic effects in Tradescantia exposed in the laboratory (p < 0.01). Ames test showed that organic extracts of winter urban air were able to induce genetic mutations in S. typhimurium TA98 strain (± S9), but not in TA100 strain, with a revertants/plate number nine times higher than the negative control. Comet assay showed that winter extracts were more toxic and genotoxic than spring extracts. All the mutagenicity tests performed confirmed that urban air in North Italy in winter contains both volatile and non-volatile genotoxic substances able to induce genetic damage in bacteria, human cells and plants.
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Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente/métodos , Mutágenos/análisis , Contaminantes Atmosféricos/toxicidad , Ensayo Cometa , Humanos , Italia , Leucocitos/química , Leucocitos/efectos de los fármacos , Pruebas de Micronúcleos , Pruebas de Mutagenicidad , Mutágenos/toxicidad , Mutación Puntual/efectos de los fármacos , Polen/química , Polen/efectos de los fármacos , Salmonella typhimurium/química , Salmonella typhimurium/efectos de los fármacos , Salmonella typhimurium/genética , Tradescantia/química , Tradescantia/efectos de los fármacosRESUMEN
We report the experimental observation and control of space and time-resolved light-matter Rabi oscillations in a microcavity. Our setup precision and the system coherence are so high that coherent control can be implemented with amplification or switching off of the oscillations and even erasing of the polariton density by optical pulses. The data are reproduced by a quantum optical model with excellent accuracy, providing new insights on the key components that rule the polariton dynamics.
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Sentinel lymph node biopsy has evolved as the surgical procedure of choice for women with clinically negative axillae, as part of an effort to move toward the less invasive surgical management of breast cancer. Axillary lymph node dissection remains the standard of care for patients with a positive axillary node and was previously performed on all patients with breast cancer prior to the implementation of the sentinel lymph node biopsy. There is, however, controversy regarding whether or not all patients with a positive sentinel lymph node need to undergo completion axillary dissection for either prognostic or therapeutic purposes. This article reviews the literature related to this controversial and evolving topic.
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Neoplasias de la Mama/patología , Neoplasias de la Mama/cirugía , Axila , Femenino , Humanos , Escisión del Ganglio Linfático , Metástasis Linfática , Biopsia del Ganglio Linfático CentinelaRESUMEN
Genotoxicity of urban air has been analysed almost exclusively in airborne particulates. We monitored the genotoxic effects of airborne pollutants in the urban air of Perugia (Central Italy). Two plant bioindicators with different genetic endpoints were used: micronuclei in meiotic pollen mother cells using Tradescantia-micronucleus bioassay (Trad-MCN) and DNA damage in nuclei of Nicotiana tabacum leaves using comet assay (Nicotiana-comet). Buds of Tradescantia clone # 4430 and young N. tabacum cv. Xanthi plants were exposed for 24 h at three sites with different pollution levels. One control site (indoor control) was also used. The two bioassays showed different sensitivities toward urban pollutants: Trad-MCN assay was the most sensitive, but DNA damage in N. tabacum showed a better correlation with the pollutant concentrations. In situ biomonitoring of airborne genotoxins using higher plants combined with chemical analysis is thus recommended for characterizing genotoxicity of urban air.
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Contaminantes Atmosféricos/toxicidad , Bioensayo/métodos , Monitoreo del Ambiente/métodos , Nicotiana/efectos de los fármacos , Tradescantia/efectos de los fármacos , Daño del ADN/efectos de los fármacos , Pruebas de Micronúcleos , Pruebas de Mutagenicidad , Nicotiana/genética , Tradescantia/genética , Salud UrbanaRESUMEN
The biomonitoring of genotoxic effects in environmental complex mixtures using higher plants is very useful for hazard evaluation. In this study we evaluated the potential application of plant genotoxicity tests in monitoring mutagens in landfill environment. The clastogenic effects of gaseous emissions (biogas)from three municipal landfills were evaluated by in situ monitoring using the Tradescantia micronucleus assay. The cytotoxicity and genotoxicity of leachates were studied using the Allium cepa test. We found no significant differences in micronuclei frequency in pollen cells of Tradescantia. Leachate samples showed elevated toxicity that inhibited root tip development in Allium cepa. Genotoxicity of the leachates was evaluated in diluted samples only. We found a significant increase in chromosomal metaphase aberrations only in one of the samples analyzed. In conclusion, biogas was not shown to be a real hazard, whereas leachates were found to display elevated toxicity. It would be advisable to treat leachates before releasing them into the environment as they can cause ecological damages. Since plant bioassays are very useful for the in situ monitoring of environmental genotoxins they are important for the prevention of environmental pollution resulting from the disposal of solid waste.
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Bioensayo/métodos , Aberraciones Cromosómicas/inducido químicamente , Cromosomas de las Plantas/efectos de los fármacos , Ciudades , Monitoreo del Ambiente/métodos , Contaminantes Ambientales/toxicidad , Mutágenos/toxicidad , Contaminantes Atmosféricos/toxicidad , Monitoreo del Ambiente/normas , Humanos , Italia , Meristema/genética , Pruebas de Mutagenicidad/métodos , Mutágenos/análisis , Cebollas/efectos de los fármacos , Cebollas/genética , Eliminación de Residuos/normas , Contaminantes del Suelo/toxicidad , Tradescantia/efectos de los fármacos , Tradescantia/genéticaRESUMEN
We experimentally demonstrate propagation of surface plasmon polaritons in the near-IR window lambda (1.45 microm,1.59 microm) at the interface of indium-tin-oxide films with different thicknesses deposited on glass. Dispersion of such polaritons is strongly dependent on the film thickness, putting into evidence a regime in which polaritons at both films's interfaces are coupled in surface supermodes. The experimental data are shown to be in good agreement with the analytical model for thin and absorbing conducting films. Measurements on aluminum-doped zinc oxide, characterized by a redshifted plasma resonance, do not show any surface plasmon polariton excitation in the same wavelength window.
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In tunnel construction workers, occupational exposure to dust (alpha-quartz and other particles from blasting), gases (nitrogen dioxide, NO(2)), diesel exhausts, and oil mist has been associated with lung function decline, induction of inflammatory reactions in the lungs with release of mediators that may influence blood coagulation, and increased risk of chronic obstructive pulmonary disease. The present molecular epidemiology study was designed to evaluate whether occupational exposure to indoor pollutants during road tunnel construction might result in genotoxic effects. A study group of 39 underground workers and a reference group of 34 unexposed subjects were examined. Primary and oxidative DNA damage, sister-chromatid exchanges (SCE), and micronuclei (MN) were measured in peripheral blood cells. The possible influences of polymorphisms in gene encoding for CYP1A1 and GSTM1 xenobiotic-metabolizing enzymes were also investigated. Exposure assessment was performed with detailed interviews and questionnaires. There were no significant differences in the level of primary and oxidative DNA damage and frequency of SCE between the tunnel workers and controls, whereas the frequency of MN showed a significant increase in exposed subjects compared to controls. No effects of CYP1A1 or GSTM1 variants were observed for the analyzed biomarkers. Since MN in peripheral blood lymphocytes are recognized as a predictive biomarker of cancer risk within a population of healthy subjects, the genotoxic risk of occupational exposure to various indoor environmental pollutants during road tunnel construction cannot be excluded by this biomonitoring study.