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BACKGROUND: Peritoneal mesothelioma (PeM) is a rare malignancy with a poor prognosis. Currently there is a lack of effective systemic therapies. Due to the rarity of PeM, it is challenging to study new treatment options. Off-label use of targeted drugs could be an effective approach. This scoping review aims to explore the genomic landscape of PeM to identify potential therapeutic targets. MATERIALS AND METHODS: A systematic literature search of Embase, Medline, Web of Science, the Cochrane Library, and Google Scholar was carried out up to 1 November 2022. Studies that reported on molecular alterations in PeM detected by high-throughput sequencing techniques were included. Genes that were altered in ≥1% of PeMs were selected for the identification of potential targeted therapies. RESULTS: Thirteen articles were included, comprising 824 PeM patients. In total, 142 genes were altered in ≥1% of patients, of which 7 genes were altered in ≥10%. BAP1 was the most commonly altered gene (50%). Other commonly altered genes were NF2 (25%), CDKN2A (23%), CDKN2B (17%), PBRM1 (15%), TP53 (14%), and SETD2 (13%). In total, 17% of PeM patients were carriers of a germline mutation, mainly in BAP1 (7%). CONCLUSIONS: This scoping review provides an overview of the mutational landscape of PeM. Germline mutations might be a larger contributor to the incidence of PeM than previously thought. Currently available targeted therapy options are limited, but several targeted agents [such as poly (ADP-ribose) polymerase (PARP), enhancer of zeste homolog 2 (EZH2), and cyclin-dependent kinase 4/6 (CDK4/6) inhibitors] were identified that might provide new targeted therapy options in the future.
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Neoplasias Pulmonares , Mesotelioma Maligno , Mesotelioma , Neoplasias Peritoneais , Humanos , Neoplasias Pulmonares/genética , Mesotelioma Maligno/genética , Mesotelioma/genética , Mesotelioma/patologia , Mutação , Neoplasias Peritoneais/genética , Neoplasias Peritoneais/patologia , Sequenciamento de Nucleotídeos em Larga Escala/métodosRESUMO
BACKGROUND: Selecting patients with peritoneal metastases from colorectal cancer (CRCPM) who might benefit from cytoreductive surgery followed by hyperthermic intraperitoneal chemotherapy (CRS-HIPEC) is challenging. Computed tomography generally underestimates the peritoneal tumor load. Diagnostic laparoscopy is often used to determine whether patients are amenable for surgery. Magnetic resonance imaging (MRI) has shown to be accurate in predicting completeness of CRS. The aim of this study is to determine whether MRI can effectively reduce the need for surgical staging. METHODS: The study is designed as a multicenter randomized controlled trial (RCT) of colorectal cancer patients who are deemed eligible for CRS-HIPEC after conventional CT staging. Patients are randomly assigned to either MRI based staging (arm A) or to standard surgical staging with or without laparoscopy (arm B). In arm A, MRI assessment will determine whether patients are eligible for CRS-HIPEC. In borderline cases, an additional diagnostic laparoscopy is advised. The primary outcome is the number of unnecessary surgical procedures in both arms defined as: all surgeries in patients with definitely inoperable disease (PCI > 24) or explorative surgeries in patients with limited disease (PCI < 15). Secondary outcomes include correlations between surgical findings and MRI findings, cost-effectiveness, and quality of life (QOL) analysis. CONCLUSION: This randomized trial determines whether MRI can effectively replace surgical staging in patients with CRCPM considered for CRS-HIPEC. TRIAL REGISTRATION: Registered in the clinical trials registry of U.S. National Library of Medicine under NCT04231175 .
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Neoplasias Colorretais/patologia , Procedimentos Cirúrgicos de Citorredução , Imageamento por Ressonância Magnética , Neoplasias Peritoneais/diagnóstico por imagem , Terapia Combinada/métodos , Humanos , Quimioterapia Intraperitoneal Hipertérmica , Laparoscopia , Estadiamento de Neoplasias/métodos , Países Baixos , Neoplasias Peritoneais/patologia , Neoplasias Peritoneais/secundário , Neoplasias Peritoneais/terapia , Qualidade de Vida , Tamanho da Amostra , Tomografia Computadorizada por Raios X , Carga TumoralRESUMO
BACKGROUND: Total pelvic exenteration (TPE) is a radical approach for locally advanced rectal cancer (LARC) and locally recurrent rectal cancer (LRRC) in case of tumour invasion into the urogenitary tract. The aim of this study is to assess surgical and oncological outcomes of TPE for LARC and LRRC in elderly patients compared to younger patients. METHODS: All patients who underwent TPE for LARC and LRRC between January 1990 and March 2017 were retrospectively analyzed. Patients aged <70 years were classified as younger and ≥70 years as elderly patients. RESULTS: In total 126 patients underwent TPE, of whom 88 younger and 38 elderly patients. Elderly patients had a significantly higher number of ASA > II patients (p = 0.01). Indication for surgery LARC (n = 73) and LRRC (n = 53) did not differ significantly. The 30-day mortality rate was significantly higher (p = 0.01) in elderly (13%) compared to younger patients (3%). Elderly patients experienced more anastomotic leakage (p = 0.02). Median overall survival (OS) was 75 months [95%CI 37.1; 112.9] for elderly and 45 months [95%CI 22.4; 67.8] for younger patients (p = 0.77). The 5-year OS rate was 44% in both groups. Median disease specific survival (DSS) was 78 months [95%CI 69.1; 86.9] for elderly and 60 months [95%CI 36.6; 83.4] for younger patients (p = 0.34). The 5-year DSS rate was 57% and 49%, respectively. CONCLUSION: TPE is an invasive treatment for rectal cancer with high 30-day mortality in elderly patients. Oncological outcomes are similar in elderly and younger patients. Therefore, TPE should not be withheld because of high age only, but careful patient selection is needed.
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Recidiva Local de Neoplasia/cirurgia , Exenteração Pélvica/efeitos adversos , Neoplasias Retais/cirurgia , Fatores Etários , Idoso , Fístula Anastomótica/etiologia , Quimiorradioterapia Adjuvante , Humanos , Pessoa de Meia-Idade , Terapia Neoadjuvante , Invasividade Neoplásica , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/terapia , Neoplasia Residual , Exenteração Pélvica/mortalidade , Neoplasias Retais/patologia , Neoplasias Retais/terapia , Estudos Retrospectivos , Taxa de SobrevidaRESUMO
In vivo dosimetry is a greatly underutilized tool for patient safety in clinical external beam radiotherapy treatments, despite being recommended by several national and international organizations (AAPM, ICRU, IAEA, NACP). The reasons for this underutilization mostly relate to the feasibility and cost of in vivo dosimetry methods. Due to the increase in the number of beam angles and dose per fraction in modern treatments, there is a compelling need for a novel dosimeter that is robust and affordable while able to operate properly in these complex conditions. This work presents a gel patch dosimeter as a novel method of in vivo dosimetry. DEFGEL, a 6% T normoxic polyacrylamide gel, was injected into 1 cm thick acrylic molds to create 1 cm thick small cylindrical patch dosimeters. To evaluate the change in optical density due to radiation induced polymerization, dosimeters were scanned before and after irradiation using an in-house developed laser densitometer. The dose-responses of three separate batches of gel were evaluated and compared to check for linearity and repeatability. The response development time was evaluated to ensure that the patch dosimeter could be high throughput. Additionally, the potential of this system to be used as an in vivo dosimeter was tested with a clinically relevant end-to-end in vivo phantom test. All irradiations were performed with a Varian Clinac 21EX at the University of Wisconsin Medical Radiation Research Center (UWMRRC). The dose-response of all three batches of gel was found to be linear within the range of 2-20 Gy. At doses below 0.5 Gy the statistical uncertainties were prohibitively large to make quantitative assessments of the results. The three batches demonstrated good repeatability in the range of 2 Gy to up to 10 Gy, with only slight variations in response at higher doses. For low doses the dosimeter fully developed within an hour while at higher doses they fully developed within four hours. During the in vivo phantom test the predicted patch absorbed dose was 4.23 Gy while the readout dose was evaluated to be 4.37 Gy, which corresponds to a 3.2% discrepancy. The dosimeter and densitometer pairing shows promise as an in vivo dosimetry system, especially for hypofractionated or MRI-guided radiotherapy treatments where higher doses are prescribed.
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Dosimetria in Vivo/métodos , Dosímetros de Radiação , Resinas Acrílicas/efeitos da radiação , Géis/efeitos da radiação , Humanos , Imagens de Fantasmas , Dosagem RadioterapêuticaRESUMO
Fast radio bursts are millisecond-duration astronomical radio pulses of unknown physical origin that appear to come from extragalactic distances. Previous follow-up observations have failed to find additional bursts at the same dispersion measure (that is, the integrated column density of free electrons between source and telescope) and sky position as the original detections. The apparent non-repeating nature of these bursts has led to the suggestion that they originate in cataclysmic events. Here we report observations of ten additional bursts from the direction of the fast radio burst FRB 121102. These bursts have dispersion measures and sky positions consistent with the original burst. This unambiguously identifies FRB 121102 as repeating and demonstrates that its source survives the energetic events that cause the bursts. Additionally, the bursts from FRB 121102 show a wide range of spectral shapes that appear to be predominantly intrinsic to the source and which vary on timescales of minutes or less. Although there may be multiple physical origins for the population of fast radio bursts, these repeat bursts with high dispersion measure and variable spectra specifically seen from the direction of FRB 121102 support an origin in a young, highly magnetized, extragalactic neutron star.
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INTRODUCTION: The objective of this study was to conduct a multicentre data analysis to identify prognostic factors for developing an axillary recurrence (AR) after negative sentinel lymph node biopsy (SLNB) in a large cohort of breast cancer patients with long follow-up. PATIENTS AND METHODS: The prospective databases from different hospitals of clinically node negative breast cancer patients operated on between, 2000 and 2002 were analyzed. SLNB was performed and pathological analysis done by local pathologists according to national guidelines. Adjuvant treatment was given according to contemporary guidelines. Multivariate analysis was performed using all available variables, a p-value of <0,05 was considered to be significant. RESULTS: A total of 929 patients who did not undergo axillary lymph node dissection were identified. After a median follow up of 77 (range 1-106) months, fifteen patients developed an isolated AR (AR rate 1,6%). Multivariate analysis showed that young age (p = 0.007) and the absence of radiotherapy (p = 0.010) significantly increased the risk of developing an AR. Distant metastasis free survival (DMFS) was significantly worse for patients with an AR compared to all other breast cancer patients (p < 0,0001). CONCLUSION: Even after long-term follow up, the risk of developing an AR after a negative SLN in breast cancer is low. Young age and absence of radiation therapy are highly significant factors for developing an axillary recurrence. DMFS is worse for AR patients compared to patients initially diagnosed with N0 or N1 disease.
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Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Linfonodos/patologia , Recidiva Local de Neoplasia/etiologia , Recidiva Local de Neoplasia/mortalidade , Biópsia de Linfonodo Sentinela/efeitos adversos , Adulto , Idoso , Axila , Neoplasias da Mama/terapia , Estudos de Coortes , Terapia Combinada , Intervalos de Confiança , Bases de Dados Factuais , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Excisão de Linfonodo/métodos , Pessoa de Meia-Idade , Análise Multivariada , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Razão de Chances , Estudos Prospectivos , Medição de Risco , Biópsia de Linfonodo Sentinela/métodos , Biópsia de Linfonodo Sentinela/estatística & dados numéricos , Análise de Sobrevida , Resultado do TratamentoRESUMO
Agreement has recently emerged for measurement of only three parameters in routine quality assurance. These include element or channel failure (EOCF), maximum depth of penetration (MDOP) and distance measurement accuracy (DMA). The related study leading to this agreement was done at the Mayo Clinic ["Four-year experience with a clinical ultrasound quality control program," Hangiandreou et al. Ultrasound Med & Biol, vol. 37, pp. 1350-1357 (2011)]. A variety of phantoms have been proposed for performing these measurements. These include: 1) a phantom with both flat and cone-shaped scanning windows, tissue-mimicking material and parallel nylon fibers for measuring all three parameters; 2) a starch suspension in water phantom for assessing ECOF; 3) polyurethane phantom for determining ECOF and estimating MDOP; 4) a silicone phantom for determining ECOF. Determination of ECOF and MDOP requires acquisition of image cine loops including many statistically independent versions; analysis of the data requires averaging of the images in the cine loops, and software is being tested at the time of this writing for user-friendly downloading and averaging of the cine images. The phantoms will be described and examples of procedures and results for making measurements. One method for assessing imaging performance involves quantifying the detectability of small low-echo spheres as a function of depth; detectability will depend on sphere size and on depth. It can be argued that the smaller the sphere and the greater the detectability, the better the scanner can delineate the boundary of an inclusion such as a spiculated cancer. Phantoms and software will be described which allow quantitative determination of detectability of low-echo spheres ( 40 dB) as a function of depth; one phantom has a spatially random distribution of 4-mm diameter low-echo spheres for lower frequencies, and the other 2-mm diameter spheres for higher frequencies. The parameter that is quantified is the mean lesion signal-to-noise ratio (LSNR) as described for cylinders by Lopez H et al. IEEE Trans Med Imaging, 1992 and for spheres by Kofler et al. Ultrasound Med & Biol, 2005. The phantoms accommodate any size and shape transducer. Note that spheres have no preferred orientation; therefore, phased arrays and convex (curved) arrays with a broad range of radii of curvature and sector angles can be can be assessed. Phantoms for assessing other aspects of performance such as quantitative determination of the contrast of large objects in a background will also be discussed.
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BACKGROUND: In breast cancer surgery, intraoperative frozen section (FS) analysis of sentinel lymph nodes (SLNs) enables axillary lymph node dissection (ALND) during the same operative procedure. In case of discordance between a "negative" FS analysis and definitive histology, an ALND as a second operation is advocated since additional lymph node metastases may be present. The clinical implications of the subsequent ALND in these patients were evaluated. MATERIALS AND METHODS: Between November 2000 and May 2008, 879 consecutive breast cancer patients underwent surgery including sentinel lymph node biopsy (SLNB) with intraoperative FS analysis of 2 central cuts from axillary SLNs. Following fixation and serial sectioning, SLNs were further examined postoperatively with hematoxylin and eosin (H&E) and immunohistochemical techniques. For patients with a discordant FS examination, the effect of the pathology findings of the subsequent ALND specimen on subsequent nonsurgical therapy were evaluated. RESULTS: FS analysis detected axillary metastases in the SLN(s) in 200 patients (23%), while the definitive pathology examination detected metastases in SLNs in another 151 patients (17%). A complementary ALND was performed in 108 of the 151 patients with discordant FS. Additional tumor positive axillary lymph nodes were found in 17 patients (16%), leading to "upstaging" in 7 (6%). Subsequent nonsurgical treatment was adjusted in 4 patients (4%): all 4 had more extensive locoregional radiotherapy; no patient received additional hormonal and/or chemotherapy. CONCLUSION: Discordance between intraoperative FS analysis and definitive histology of SLNs is common. In this selection of patients, a substantial proportion had additional lymph node metastases, but postsurgical treatment was rarely adjusted based on the findings of the complementary ALND.
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Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Secções Congeladas/normas , Excisão de Linfonodo , Linfonodos/patologia , Biópsia de Linfonodo Sentinela , Adulto , Idoso , Idoso de 80 Anos ou mais , Axila , Carcinoma Ductal de Mama/secundário , Carcinoma Ductal de Mama/cirurgia , Carcinoma Lobular/secundário , Carcinoma Lobular/cirurgia , Feminino , Seguimentos , Humanos , Período Intraoperatório , Linfonodos/cirurgia , Metástase Linfática , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Estudos ProspectivosRESUMO
Perfluorooctanoic acid (PFOA) is an industrial chemical that has become disseminated globally in aquatic and terrestrial habitats, humans, and wildlife. Understanding PFOA's biodegradability (susceptibility to microbial metabolic attack) is a crucial element in developing an informed strategy for predicting and managing this compound's environmental fate. Reasoning that PFOA might be susceptible to reductive defluorination by anaerobic microbial communities, we embarked on a 2-phase experimental approach examining the potential of five different microbial communities (from a municipal waste-water treatment plant, industrial site sediment, an agricultural soil, and soils from two fire training areas) to alter PFOA's molecular structure. A series of primarily anaerobic incubations (up to 259d in duration) were established with acetate, lactate, ethanol, and/or hydrogen gas as electron donors and PFOA (at concentrations of 100 ppm and 100 ppb) as the electron acceptor. Cometabolism of PFOA during reductive dechlorination of trichloroethene (TCE) and during reduction of nitrate, iron, sulfate, and methanogenesis were also examined. Endpoints of potential PFOA transformation included release of fluoride and detection of potential transformation products by LC/Orbitrap MS and LC/accurate radioisotope counting in a (14)C radiotracer study. The strongest indication of PFOA transformation occurred during its potential cometabolism at the 100 ppb concentration during reductive dechlorination of TCE. Despite an extensive search for transformation products to corroborate potential cometabolism of PFOA, we were unable to document any alteration of PFOA's chemical structure. We conclude that, under conditions examined, PFOA is microbiologically inert, hence environmentally persistent.
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Caprilatos/metabolismo , Poluentes Ambientais/metabolismo , Fluorocarbonos/metabolismo , Bactérias/metabolismo , Biodegradação Ambiental , Caprilatos/análise , Caprilatos/toxicidade , Poluentes Ambientais/análise , Poluentes Ambientais/toxicidade , Fluorocarbonos/análise , Fluorocarbonos/toxicidade , Fungos/metabolismo , Fenômenos Microbiológicos/efeitos dos fármacosRESUMO
BACKGROUND: The prognostic meaning and thus indication for adjuvant therapy of lymphogenic micrometastases in breast cancer patients is still under debate. PATIENTS AND METHODS: From 1999 to 2007, 703 patients with (c)T(1-2)N(0) breast cancer underwent surgery including sentinel lymph node biopsy. Examination of sentinel lymph nodes consisted of hematoxylin and eosin and immunohistochemistry staining following serial sectioning of the sentinel node. Patients were divided into four groups: (p)N(0) (n=423), (p)N(1micro) (n=81), (p)N(1a) (n=130) and (p)N(>or=1b) (n=69). Median follow-up was 40 months. RESULTS: At the end of follow-up, 53 patients had died and 64 had recurrent disease. Compared with (p)N(0) and following adjustment for possible confounders, including adjuvant systemic treatment, overall survival was not significantly different for (p)N(1micro) while significantly worse for (p)N(1a) and (p)N(>or=1b) {hazard ratio (HR) [95% confidence interval (CI)]: 0.59 [0.14-2.58], 4.31 [1.85-10.01], 10.66 [4.04-28.14], respectively}. Likewise, disease-free survival was not significantly different for (p)N(1micro) and worse for (p)N(1a) and (p)N(>or=1b) (HR [95% CI]: 1.43 [0.67-3.02], 2.79 [1.37-5.66], 7.13 [3.27-15.54], respectively). Distant metastases were more commonly observed in the (p)N(1micro) than in the (p)N(0) group, but still not as common as in the (p)N(1a) or (p)N(>or=1b) group (HR [95% CI]: 4.85 [1.79-13.18], 10.34 [3.82-28.00], 23.25 [7.88-68.56], respectively). CONCLUSION: Although the risk of distant metastases was higher in patients in the (p)N(1micro) than in the (p)N(0) group, no statistically significant differences were observed in overall or disease-free survival between (p)N(0) and (p)N(1micro). Micrometastatic lymph node involvement in itself should not be an indication for adjuvant chemotherapy in breast cancer patients.
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Neoplasias da Mama/diagnóstico , Neoplasias da Mama/patologia , Carcinoma/diagnóstico , Carcinoma/patologia , Biópsia de Linfonodo Sentinela , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos Hormonais/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/cirurgia , Carcinoma/tratamento farmacológico , Carcinoma/cirurgia , Quimioterapia Adjuvante , Estudos de Coortes , Feminino , Seguimentos , Humanos , Metástase Linfática , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Resultado do Tratamento , Carga Tumoral/fisiologia , Adulto JovemRESUMO
Accurate determination of the complex shear modulus of soft tissues and soft-tissue-like materials in the 10-300 Hz frequency range is very important to researchers in MR elastography and acoustic radiation force impulse (ARFI) imaging. A variety of instruments for making such measurements has been reported, but none of them is easily reproduced, and none have been tested to conform to causality via the Kramers-Kronig (K-K) relations. A promising linear oscillation instrument described in a previous brief report operates between 20 and 160 Hz, but results were not tested for conformity to the K-K relations. We have produced a similar instrument with our own version of the electronic components and have also accounted for instrumental effects on the data reduction, which is not addressed in the previous report. The improved instrument has been shown to conform to an accurate approximation of the K-K relations over the 10-300 Hz range. The K-K approximation is based on the Weichert mechanical circuit model. We also found that the sample thickness must be small enough to obtain agreement with a calibrated commercial rheometer. A complete description of the improved instrument is given, facilitating replication in other labs.
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Materiais Biomiméticos/química , Técnicas de Imagem por Elasticidade/instrumentação , Resistência ao Cisalhamento , Artefatos , Calibragem , Reagentes de Ligações Cruzadas/química , Formaldeído/química , Gelatina/química , Laboratórios , Sensibilidade e EspecificidadeRESUMO
Compared to conventional piezoelectric transducers, new capacitive microfabricated ultrasonic transducer (CMUT) technology is expected to offer a broader bandwidth, higher resolution and advanced 3D/4D imaging inherent in a 2D array. For ultrasound scatterer size imaging, a broader frequency range provides more information on frequency-dependent backscatter, and therefore, generally more accurate size estimates. Elevational compounding, which can significantly reduce the large statistical fluctuations associated with parametric imaging, becomes readily available with a 2D array. In this work, we show phantom and in vivo breast tumor scatterer size image results using a prototype 2D CMUT transducer (9 MHz center frequency) attached to a clinical scanner. A uniform phantom with two 1 cm diameter spherical inclusions of slightly smaller scatterer size was submerged in oil and scanned by both the 2D CMUT and a conventional piezoelectric linear array transducer. The attenuation and scatterer sizes of the sample were estimated using a reference phantom method. RF correlation analysis was performed using the data acquired by both transducers. The 2D CMUT results indicate that at a 2 cm depth (near the transmit focus for both transducers) the correlation coefficient reduced to less than 1/e for 0.2 mm lateral or 0.25 mm elevational separation between acoustic scanlines. For the conventional array this level of decorrelation requires a 0.3 mm lateral or 0.75 mm elevational translation. Angular and/or elevational compounding is used to reduce the variance of scatterer size estimates. The 2D array transducer acquired RF signals from 140 planes over a 2.8 cm elevational direction. If no elevational compounding is used, the fractional standard deviation of the size estimates is about 12% of the mean size estimate for both the spherical inclusion and the background. Elevational compounding of 11 adjacent planes reduces it to 7% for both media. Using an experimentally estimated attenuation of 0.6 dB cm(-1) MHz(-1), scatterer size estimates for an in vivo breast tumor also demonstrate improvements using elevational compounding with data from the 2D CMUT transducer.
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Acústica , Ultrassom , Neoplasias da Mama/diagnóstico , Fibroadenoma/diagnóstico , Humanos , Imagens de Fantasmas , TransdutoresRESUMO
Laboratory incubations of coal-tar waste-contaminated sediment microbial communities under relatively controlled physiological conditions were used to interpret results of a field-based stable isotope probing (SIP) assay. Biodegradation activity of 13C-benzene was examined by GC/MS determination of net 13CO2 production and by GC headspace analysis of benzene loss. Key experimental variables were: the site of the assays (laboratory serum-bottle incubations and in situ field sediments), benzene concentration (10, 36 or 200 p.p.m. in laboratory assays), and physiological conditions (anaerobic with or without sulfate or nitrate additions versus aerobic headspace or the uncontrolled field). In anaerobic laboratory incubations of benzene at 10 p.p.m., greater than 60% of the substrate was eliminated within 15 days. During anaerobic incubations of 200 p.p.m. benzene (70 days), 0.9% benzene mineralization occurred. When benzene (36 p.p.m.) was added to sediment with air in the serum-bottle headspace, 14% of the initial 13C was mineralized to 13CO2 in 2.5 days. In the field experiment (178 microg 13C-benzene dosed to undisturbed sediments), net 13CO2 production reached 0.3% within 8.5 h. After isopycnic separation of 13C (heavy)-labelled DNA from the above biodegradation assays, sequencing of 13C-DNA clone libraries revealed a broad diversity of taxa involved in benzene metabolism and distinctive libraries for each biodegradation treatment. Perhaps most importantly, in the field SIP experiment the clone libraries produced were dominated by Pelomonas (betaproteobacteria) sequences similar to those found in the anaerobic 10 p.p.m. benzene laboratory experiment. These data indicate that the physiological conditions that prevail and govern in situ biodegradation of pollutants in the field may be interpreted by knowing the physiological preferences of potentially active populations.
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Bactérias Aeróbias/metabolismo , Bactérias Anaeróbias/metabolismo , Benzeno/metabolismo , Água Doce/microbiologia , Sedimentos Geológicos/microbiologia , Bactérias Aeróbias/isolamento & purificação , Bactérias Anaeróbias/isolamento & purificação , Biodegradação Ambiental , Reatores Biológicos , Isótopos de Carbono/metabolismo , Alcatrão , Biblioteca GênicaAssuntos
Aspirina/farmacologia , Inibidores de Ciclo-Oxigenase/farmacologia , Resistência a Medicamentos , Inibidores da Agregação Plaquetária/farmacologia , Agregação Plaquetária/efeitos dos fármacos , Testes de Função Plaquetária/instrumentação , Artefatos , Plaquetas/enzimologia , Ciclo-Oxigenase 1/sangue , Seguimentos , Humanos , Doenças Vasculares Periféricas/sangue , Reprodutibilidade dos Testes , Reologia , Estresse MecânicoRESUMO
Minimally invasive therapies (such as radiofrequency ablation) are becoming more commonly used in the United States for the treatment of hepatocellular carcinomas and liver metastases. Unfortunately, these procedures suffer from high recurrence rates of hepatocellular carcinoma ( approximately 34-55%) or metastases following ablation therapy. The ability to perform real-time temperature imaging while a patient is undergoing radiofrequency ablation could provide a significant reduction in these recurrence rates. In this paper, we demonstrate the feasibility of ultrasound-based temperature imaging on a tissue-mimicking phantom undergoing radiofrequency heating. Ultrasound echo signals undergo time shifts with increasing temperature, which are tracked using 2D correlation-based speckle tracking methods. Time shifts or displacements in the echo signal are accumulated, and the gradient of these time shifts are related to changes in the temperature of the tissue-mimicking phantom material using a calibration curve generated from experimental data. A tissue-mimicking phantom was developed that can undergo repeated radiofrequency heating procedures. Both sound speed and thermal expansion changes of the tissue-mimicking material were measured experimentally and utilized to generate the calibration curve relating temperature to the displacement gradient. Temperature maps were obtained, and specific regions-of-interest on the temperature maps were compared to invasive temperatures obtained using fiber-optic temperature probes at the same location. Temperature elevation during a radiofrequency ablation procedure on the phantom was successfully tracked to within +/-0.5 degrees C.
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Ablação por Cateter/métodos , Interpretação de Imagem Assistida por Computador/métodos , Cirurgia Assistida por Computador/métodos , Termografia/métodos , Ultrassonografia/métodos , Estudos de Viabilidade , Humanos , Imagens de Fantasmas , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Ultrassonografia/instrumentaçãoRESUMO
BACKGROUND AND OBJECTIVES: The benefit of an inferior vena cava (IVC) filter in addition to standard anticoagulation regimens is unknown. METHODS: We examined data for patients who received IVC filters with anticoagulation (AC-Filter) after an episode of venous thromboembolism (VTE) and compared them with data for those who received anticoagulation only (AC-Only). Outcome measures were new pulmonary embolism (PE), recurrent deep vein thrombosis (DVT), and mortality at 90 days and at 5 years. Demographic data included age, gender, and ethnicity/race, prior thromboembolic history, cancer, serum albumin, and time in therapeutic range. In addition, subsets matched for age, gender and race/ethnicity were examined in detail. RESULTS: AC-Filter patients (n = 251), when compared to AC-Only patients (n = 1377), did not differ significantly with regard to gender or cancer status, but white males in general had better outcomes. AC-Filter patients were more likely to have had a previous history of PE or VTE (P < 0.001). In comparison to AC-Only patients, AC-Filter patients had lower mean serum albumin levels (3.1 +/- 0.8 vs. 3.6 +/-0.8 mg dL(-1), P < 0.001) and were older (65 +/- 16.1 years vs. 60 +/- 17.5 years, P < 0.001). After stratification according to previous history of PE or VTE prior to the index VTE event, no differences in the outcome measures of new PE, recurrent DVT or mortality were identified between groups, but patients with a prior history of PE from either group were more likely to have a new PE (hazard ratio 1.9, P < 0.001). CONCLUSIONS: These data suggest that IVC filters may not provide any substantial additional benefit for patients who can tolerate anticoagulant therapy.
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Anticoagulantes/uso terapêutico , Tromboembolia/tratamento farmacológico , Filtros de Veia Cava , Estudos de Coortes , Humanos , Tromboembolia/cirurgiaRESUMO
In current ultrasound elastography, only the axial component of the displacement vector is estimated and used to produce strain images. A method was recently proposed by our group to estimate both the axial and lateral components of a displacement vector following a uniaxial compression. Previous work evaluated the technique using both simulations and a mechanically translated phased array transducer. In this paper, we present initial results using beam steering on a linear array transducer attached to a commercial scanner to acquire echo signals for estimating 2-D displacement vectors. Single-inclusion and anthropomorphic breast phantoms with different boundary properties between the inclusion and background material are imaged by acquiring echo data along beam lines ranging from -15 degrees to 15 degrees relative to the compression direction. 1-D cross-correlation is used to calculate "angular displacements" in each acquisition direction, yielding axial and lateral components of the displacement vector. Strain tensor components are estimated from these displacements. Features on shear strain images generated for the inclusion phantom agree with those predicted using FEA analysis. Experimental results demonstrate the utility of this technique on clinical scanners. Shear strain tensors obtained using this method may provide useful information for the differentiation of benign from malignant tumors. For the linear array transducer used in this study, the optimum angular increment is around 3 degrees. However, more work is required for the selection of an appropriate value for the maximum beam angle for optimal performance of this technique.
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Aumento da Imagem , Interpretação de Imagem Assistida por Computador , Transdutores , Ultrassonografia/métodos , Humanos , Modelos Teóricos , Imagens de Fantasmas , Estresse MecânicoRESUMO
The aim of the present study was to examine the patterns of complementary and alternative medicine (CAM) use in a sample of head and neck cancer patients, forming part of a larger study. A cross-sectional survey design was used collecting data through a descriptive 27-item questionnaire in nine countries in Europe. The participants were 75 patients with head and neck cancers. The prevalence rate of CAM use was 22.7%. The most common therapies used were herbal medicine (47%), medicinal teas (23.5%), use of vitamins/minerals (11.8%) and visualization (11.8%). Use of CAM dramatically increased after the diagnosis with cancer (i.e. eightfold increase in the use of herbs). A profile of CAM users was not evident in this sample. Patients used CAM for a variety of reasons together, with counteracting the ill effects from cancer and its treatment being the most common one. Information about CAM was obtained mostly from friends and family. As one in five head and neck cancer patients use CAM it is important that clinicians explore practices with their patients, improve communication about CAM with them and assist those who want to use CAM in using appropriate and safe therapies.
Assuntos
Terapias Complementares/estatística & dados numéricos , Neoplasias de Cabeça e Pescoço/terapia , Terapias Complementares/métodos , Estudos Transversais , Europa (Continente) , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , AutomedicaçãoRESUMO
BACKGROUND: The aim of this study was to explore the use of complementary and alternative medicine (CAM) in cancer patients across a number of European countries. METHODS: A descriptive survey design was developed. Fourteen countries participated in the study and data was collected through a descriptive questionnaire from 956 patients. RESULTS: Data suggest that CAM is popular among cancer patients with 35.9% using some form of CAM (range among countries 14.8% to 73.1%). A heterogeneous group of 58 therapies were identified as being used. Herbal medicines and remedies were the most commonly used CAM therapies, together with homeopathy, vitamins/minerals, medicinal teas, spiritual therapies and relaxation techniques. Herbal medicine use tripled from use before diagnosis to use since diagnosis with cancer. Multivariate analysis suggested that the profile of the CAM user was that of younger people, female and with higher educational level. The source of information was mainly from friends/family and the media, while physicians and nurses played a small part in providing CAM-related information. The majority used CAM to increase the body's ability to fight cancer or improve physical and emotional well-being, and many seemed to have benefited from using CAM (even though the benefits were not necessarily related to the initial reason for using CAM). Some 4.4% of patients, however, reported side-effects, mostly transient. CONCLUSIONS: It is imperative that health professionals explore the use of CAM with their cancer patients, educate them about potentially beneficial therapies in light of the limited available evidence of effectiveness, and work towards an integrated model of health-care provision.