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PURPOSE: The Vienna and Venezia (Elekta) are hybrid intracavitary/interstitial brachytherapy (BT) applicators for cervical cancers unsuitable for intracavitary BT alone to improve target coverage or reduce critical organ dose. There is limited outcome data with the use of these applicators outside published experience of the EMBRACE group. We report feasibility and early outcomes with the use of these hybrid applicators at our institution. METHODS AND MATERIALS: Hybrid applicators were used to treat 61 patients with cervical cancer from November 2011 to December 2019. Indications for hybrid applicator use were involvement of the vagina in 10 patients (16%), residual central or parametrial disease in 46 patients (75%), and a narrow introitus in 5 patients (9%). Toxicities were graded using the CTCAE v4.0. Outcomes were assessed with the Kaplan-Meier method. RESULTS: Median follow-up was 16 months (IQR 9-32 mos). Median HRCTV volume was 31.6 cm3 (IQR 25-48 cm3). Median HRCTV D90 was 86.1 Gy (IQR 84.3-88.0 Gy). In 54 patients with follow-up PET/CT at 3 months, complete initial imaging response locally was seen in 46 patients.Estimated 12-month Kaplan-Meier overall survival, locoregional control, distant control, and recurrence-free survival estimates were 86.9%, 80.6%, 73.8%, and 65.9%, respectively. The 12-month incidence of Grade 3+ GI/GU chronic toxicities was 5.7%, consisting of vesicovaginal fistula, rectovaginal fistula, and ureterovesical fistula. CONCLUSIONS: Our single-institution data support the use of the hybrid applicators, as an alternative to traditional BT applicators when clinically warranted. Use of hybrid applicators is feasible with adequate coverage of disease in the vagina and parametrium.
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Braquiterapia , Neoplasias do Colo do Útero , Braquiterapia/métodos , Quimiorradioterapia , Feminino , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Dosagem Radioterapêutica , Neoplasias do Colo do Útero/radioterapiaRESUMO
Nanostructured ZnO nanoarrays deposited on silicon oriented substrates is a very promising area in the study of the control of physicochemical properties, in which photoluminescence plays a crucial role. This optical property inherent to ZnO, can be favorably modified through the inclusion of doping elements, with the purpose of appropriately modifying their optical absorption and luminescence. Following this objective, in the present work we present the development of Zn(1-x-y)Ce(x)Eu(y)O nanostructured thin films. The samples were produced in two steps process by atomic layer deposition technique followed by a solvothermal synthesis. The purpose of Cerium and Europium incorporation into the ZnO compound is to enhance the photoluminescence in ZnO thin films. In a first stage textured thin films were obtained from diethylzinc at a temperature of 190 °C and a pressure of 3.29 × 10-4 atm, on silicon substrates (111). Subsequently, the perpendicular growth of nanostructures was induced under a solvothermal process, where Zn(NO3)2 was used as Zn precursor and hexamethylene-tetramine operating as a dual-ligand to promote the linking of Zn2+ ions. The growth of cerium-europium ZnO nanostructures was promoted with Ce(C2H3O2)3·H2O and Eu(NO3)3·5H2O. The obtained Zn(1-x-y)Ce(x)Eu(y)O nanostructured thin films, were examined through SEM-microscopy, x-ray diffraction, x-ray photoelectron spectroscopy and photoluminescence studies. The attained results show that it is feasible to produce Ce-Eu-doped ZnO nanostructures with tailored photoluminescence and crystal size. Interestingly the Ce-Eu doping induces a strong shift in comparison to the typical UV emission of ZnO; an effect that can be related with the increase of lattice defects in ZnO.
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The complete genome sequence of a novel comovirus identified in Guanajuato, Mexico, in a common bean plant (Phaseolus vulgaris L.) coinfected with Phaseolus vulgaris alphaendornavirus 1 (PvEV-1) and Phaseolus vulgaris alphaendornavirus 2 (PvEV-2) is presented. According to the current ICTV taxonomic criteria, this comovirus corresponds to a new species, and the name "Phaseolus vulgaris severe mosaic virus" (PvSMV) is proposed for this virus based on the observed symptoms of "severe mosaic" syndrome caused by comoviruses in common bean. PvSMV is closely related to bean pod mosaic virus (BPMV), and its genome consists of two polyadenylated RNAs. RNA-1 (GenBank accession number MN837498) is 5969 nucleotides (nt) long and encodes a single polyprotein of 1856 amino acids (aa), with an estimated molecular weight (MW) of 210 kDa, that contains putative proteins responsible for viral replication and proteolytic processing. RNA-2 (GenBank accession number MN837499) is 3762 nt long and encodes a single polyprotein of 1024 aa, with an estimated MW of 114 kDa, that contains putative movement and coat proteins. Cleavage sites were predicted based on similarities in size and homology to aa sequences of other comoviruses available in the GenBank database. Symptoms associated with PvSMV include mosaic, local necrotic lesions, and apical necrosis. This is the first report of a comovirus infecting common bean in Mexico.
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Comovirus/genética , Genoma Viral , Phaseolus/virologia , Doenças das Plantas/virologia , Sequência de Aminoácidos , Comovirus/classificação , Comovirus/isolamento & purificação , México , Filogenia , RNA Viral/genética , Proteínas Virais/genética , Sequenciamento Completo do GenomaRESUMO
Hysteresis loops exhibited by the thermal properties of undoped and 0.8 at.% W-doped nanocrystalline powders of VO2 synthesized by means of the solution combustion method and compacted in pellets, are experimentally measured by photothermal radiometry. It is shown that: (i) the W doping reduces both the hysteresis loops of VO2 and its transition temperature up to 15 °C. (ii) The thermal diffusivity decreases (increases) until (after) the metallic domains become dominant in the VO2 insulating matrix, such that its variation across the metal-insulation transition is enhanced by 23.5% with W-0.8 at.% doping. By contrast, thermal conductivity (thermal effusivity) increases up to 45% (40%) as the metallic phase emerges in the VO2 structure due to the insulator-to-metal transition, and it enhances up to 11% (25%) in the insulator state when the local rutile phase is induced by the tungsten doping. (iii) The characteristic peak of the VO2 specific heat capacity is observed in both heating and cooling processes, such that the phase transition of the 0.8 at.% W-doped sample requires about 24% less thermal energy than the undoped one. (iv) The impact of the W doping on the four above-mentioned thermal properties of VO2 mainly shows up in its insulator phase, as a result of the distortion of the local lattice induced by the electrons of tungsten. W doping at 0.8 at.% thus enhances the VO2 capability to transport heat but diminishes its thermal switching efficiency.
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Prokaryotes represent an ancestral lineage in the tree of life and constitute optimal resources for investigating the evolution of genomes in unicellular organisms. Many bacterial species possess multipartite genomes offering opportunities to study functional variations among replicons, how and where new genes integrate into a genome, and how genetic information within a lineage becomes encoded and evolves. To analyze these issues, we focused on the model soil bacterium Sinorhizobium meliloti, which harbors a chromosome, a chromid (pSymB), a megaplasmid (pSymA), and, in many strains, one or more accessory plasmids. The analysis of several genomes, together with 1.4 Mb of accessory plasmid DNA that we purified and sequenced, revealed clearly different functional profiles associated with each genomic entity. pSymA, in particular, exhibited remarkable interstrain variation and a high density of singletons (unique, exclusive genes) featuring functionalities and modal codon usages that were very similar to those of the plasmidome. All this evidence reinforces the idea of a close relationship between pSymA and the plasmidome. Correspondence analyses revealed that adaptation of codon usages to the translational machinery increased from plasmidome to pSymA to pSymB to chromosome, corresponding as such to the ancestry of each replicon in the lineage. We demonstrated that chromosomal core genes gradually adapted to the translational machinery, reminiscent of observations in several bacterial taxa for genes with high expression levels. Such findings indicate a previously undiscovered codon usage adaptation associated with the chromosomal core information that likely operates to improve bacterial fitness. We present a comprehensive model illustrating the central findings described here, discussed in the context of the changes occurring during the evolution of a multipartite prokaryote genome.IMPORTANCE Bacterial genomes usually include many thousands of genes which are expressed with diverse spatial-temporal patterns and intensities. A well-known evidence is that highly expressed genes, such as the ribosomal and other translation-related proteins (RTRPs), have accommodated their codon usage to optimize translation efficiency and accuracy. Using a bioinformatic approach, we identify core-genes sets with different ancestries, and demonstrate that selection processes that optimize codon usage are not restricted to RTRPs but extended at a genome-wide scale. Such findings highlight, for the first time, a previously undiscovered adaptation strategy associated with the chromosomal-core information. Contrasted with the translationally more adapted genes, singletons (i.e., exclusive genes, including those of the plasmidome) appear as the gene pool with the less-ameliorated codon usage in the lineage. A comprehensive summary describing the inter- and intra-replicon heterogeneity of codon usages in a complex prokaryote genome is presented.
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Cromossomos Bacterianos , Uso do Códon , Evolução Molecular , Genoma Bacteriano , Sinorhizobium meliloti/genética , Biologia Computacional , DNA Ribossômico/genética , Genes Bacterianos , Plasmídeos/genética , RepliconRESUMO
We studied the soft landing of Ni atoms on a previously damaged graphene sheet by means of molecular dynamics simulations. We found a monotonic decrease of the cluster frequency as a function of its size, but few big clusters comprise an appreciable fraction of the total number of Ni atoms. The aggregation of Ni atoms is also modeled by means of a simple phenomenological model. The results are in clear contrast with the case of hard or energetic landing of metal atoms, where there is a tendency to form mono-disperse metal clusters. This behavior is attributed to the high diffusion of unattached Ni atoms, together with vacancies acting as capture centers. The findings of this work show that a simple study of the energetics of the system is not enough in the soft landing regime, where it is unavoidable to also consider the growth process of metal clusters.
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Some pollutants can be resistant to wastewater treatment, hence becoming a risk to aquatic and terrestrial biota even at the very low concentrations (ng L-1-µg L-1) they are commonly found at. Tertiary treatments are used for micropollutant removal but little is known about the ecotoxicity of the treated effluent. In this study, a municipal secondary effluent was treated by a solar photo-Fenton reactor at initial neutral pH in a raceway pond reactor, and ecotoxicity was evaluated before and after micropollutant removal. Thirty-nine micropollutants were identified in the secondary effluent, mainly pharmaceuticals, with a total concentration of ≈80 µg L-1. After treatment, 99 % microcontaminant degradation was reached. As for ecotoxicity reduction, the assayed organisms showed the following sensitivity levels: Tetrahymena thermophila > Daphnia magna > Lactuca sativa > Spirodela polyrhiza ≈ Vibrio fischeri. The initial effluent showed an inhibitory effect of 40 % for T. thermophila and 20 % for D. magna. After 20 min of photo-Fenton treatment, no toxic effect was observed for T. thermophila and toxicity dropped to 5 % for D. magna. Graphical abstract Ecotoxicity removal by solar photo-Fenton at neutral pH. á .
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Lagoas , Luz Solar , Águas Residuárias/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Aliivibrio fischeri/efeitos dos fármacos , Animais , Daphnia/efeitos dos fármacos , Peróxido de Hidrogênio/química , Concentração de Íons de Hidrogênio , Ferro/químicaRESUMO
Abiotic stresses in general and extracellular acidity in particular disturb and limit nitrogen-fixing symbioses between rhizobia and their host legumes. Except for valuable molecular-biological studies on different rhizobia, no consolidated models have been formulated to describe the central physiologic changes that occur in acid-stressed bacteria. We present here an integrated analysis entailing the main cultural, metabolic, and molecular responses of the model bacterium Sinorhizobium meliloti growing under controlled acid stress in a chemostat. A stepwise extracellular acidification of the culture medium had indicated that S. meliloti stopped growing at ca. pH 6.0-6.1. Under such stress the rhizobia increased the O2 consumption per cell by more than 5-fold. This phenotype, together with an increase in the transcripts for several membrane cytochromes, entails a higher aerobic-respiration rate in the acid-stressed rhizobia. Multivariate analysis of global metabolome data served to unequivocally correlate specific-metabolite profiles with the extracellular pH, showing that at low pH the pentose-phosphate pathway exhibited increases in several transcripts, enzymes, and metabolites. Further analyses should be focused on the time course of the observed changes, its associated intracellular signaling, and on the comparison with the changes that operate during the sub lethal acid-adaptive response (ATR) in rhizobia.
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Citocromos/metabolismo , Fabaceae/microbiologia , Concentração de Íons de Hidrogênio , Rhizobium/fisiologia , Sinorhizobium meliloti/fisiologia , Estresse Fisiológico/fisiologia , Ácidos/metabolismo , Fixação de Nitrogênio , Consumo de Oxigênio , Via de Pentose Fosfato , Solo , SimbioseRESUMO
Radiotherapy is a mainstay of treatment for head and neck cancer. However, the morbidity of treatment remains a clinical challenge. Molecular profiling has provided further insight into tumor biology and tumor sensitivity to radiation, and this information could be used to personalize treatment. In this review, we discuss published signatures of radiosensitivity and discuss the pathways that may be important in dictating radiation sensitivity. Applications of these signatures could result in less morbidity if dose de-escalation efforts are successful.
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PURPOSE: To evaluate the treatment outcomes for T1 N0 glottic carcinoma after definitive radiotherapy. METHODS: One hundred and seventeen patients treated with radical radiotherapy from 1990 to 2006 were retrospectively reviewed. The median follow-up duration for the entire group was 92 months (range 4-227). A median dose of 70 Gy (range 63-70 Gy) was administered. We determined the rates of local control (LC), regional control, overall survival (OS) and cause-specific survival (CSS) at 5, 10 and 15 years by Kaplan-Meier product-limit method. The Cox regression analysis was performed to identify significant prognostic factors for LC and survival. The incidence of secondary malignancies is also reported. RESULTS: The 5-, 10- and 15-year LC rates for the whole group were 84, 80.2 and 80.2 %, respectively. There were 20 local recurrences, of which 19 were salvaged with laryngectomy, giving an ultimate control rate of 90.6 %. The 5-/10-/15-year OS and CSS rates were 81.2 %/66.1 %/48.3 % and 90.6 %/90.6 %/90.6 %, respectively. None of the parameters analyzed exhibited a statistically significant relationship with LC. The age ≥65 years had a statistically significant effect on OS (but not in CSS), with a hazard ratio of 2.45 (95 % confidence interval 1.29-4.66; p = 0.006). During follow-up, 26 patients (22 %) developed a secondary malignancy. Only two patients (1.7 %) presented with severe toxicity (edema and mucositis). CONCLUSIONS: Radiotherapy alone offers a high likelihood of LC and an excellent CSS rate. In addition, the surgical approach for the salvage is a successful option.