Guillain-Barré syndrome as an atypical manifestation of an esophageal carcinoma

Guillain-Barré syndrome (GBS) is an acute demyelinating polyradiculoneuropathy normally associated with a preceding infection, but sometimes it can be linked to a subjacent malignancy. We report an unusual case of GBS occurring as the first clinical manifestation of an esophageal adenocarcinoma in a 65-year-old patient. A GBS neuropathy of undetermined origin may be associated with an underlying tumor and esophageal cancer has to be considered in the differential diagnosi

Mechanisms and Attribution of Changes in Austral Summer Precipitation related to the South Atlantic Convergence Zone

Austral summer (DJF) precipitation over tropical South America (SA) is characterized by the South American Monsoon System (SAMS) and the South Atlantic Convergence Zone (SACZ). The increase in atmospheric temperature and water vapor content over the SA during the last decades of the 20th century could affect the duration and amplitude of the SAMS and the intensity of the SACZ. This research examines the spatial variability of precipitation trends over SE Brazil, focusing on the SACZ. More specifically, this study investigates trends in precipitation over Southeastern Brazil (SE Brazil) and examines changes in the position and intensity of the SACZ. SE Brazil is the most densely populated region in the country with a large portion of this population living in urban centers. The SACZ is important for agriculture and water supply for millions of people. One of the main goals of this research is to identify mechanisms associated with the observed changes in the characteristics of the SACZ during the last three decades of the 20th century, and examine the relative contribution of natural and anthropogenic forcing to precipitation trends. The first chapter investigates the pattern of spatial variability of precipitation trends over the coastal region of SE Brazil. This study shows that over the southern portion of the study area, precipitation is increasing due to the increase in the frequency and intensity of extreme events. Over the northern portion of the area, while the intensity of extreme events is increasing, the number of precipitating days is decreasing. This spatial pattern of precipitation trends suggests a poleward shift of the SACZ, which is investigated in the second chapter. Chapter 2 focuses on the underlying mechanisms associated with changes in precipitation intensity related to the position of the SACZ. Decadal variations in the mean state of the atmosphere suggest that the observed changes in precipitation over SE Brazil are associated with a weakening of the poleward winds along the eastern Brazilian coast that reduces the dynamic support necessary for convection along the equatorward margin of the SACZ. Additionally, this analysis also identifies a decrease in low-to-mid troposphere (700hPa) moisture over the tropical Atlantic in the recent decade that further reduces the moisture transported into the convective margin of the SACZ. Both mechanisms contribute to reducing precipitation over eastern tropical Brazil and characterize the poleward shift of the SACZ. The final chapter focuses on evaluating the contribution of natural variability and anthropogenic-related forcings to the poleward shift of the SACZ and drying conditions over eastern Brazil at the end of 20th century. Simulations from different scenarios of the Coupled Model Intercomparison Project phase 5 (CMPI5) models capable of reproducing the SACZ climatology suggest significant contribution of anthropogenic forcing on the SACZ-related precipitation trends. Despite the large discrepancies in the simulated precipitation trends, similarities among the ensemble members provide compelling evidence that the poleward shift of the SACZ in the last three decades of the 20th century is largely enhanced by anthropogenic forcing. Collectively, the three chapters of this dissertation characterize the recent changes in precipitation related to a poleward shift of the SACZ and give novel insights into the influence of anthropogenic-related forcing on these changes. These findings advance the scientific understanding of the consequences of recent climate variability and change over eastern tropical South America, particularly over the SACZ

Caracterização fenotípica de bactérias diazotróficas associadas a Tripogon spicatus no Bioma Caatinga.

O objetivo deste trabalho foi caracterizar fenotipicamente bactérias diazotróficas isoladas de exemplares da gramínea tolerante à dessecação, Tripogon spicatus, oriundos da Caatinga. As bactérias foram isoladas de solo rizosférico e de raízes de T. spicatus utilizando-se o meio de cultura BMGM semissólido para a obtenção de isolados capazes de fixar o nitrogênio atmosférico em condições microaerofílicas. Os tubos inoculados, onde foi possível observar a película característica para a fixação biológica do N em meio semissólido, foram utilizados para a obtenção dos isolados que foram purificados em meio de cultura Dyg?s sólido e avaliados quanto às principais características culturais. Para cada uma das características, a diferença do número de isolados entre o solo rizosférico e a raiz foi avaliada através do teste F. Foi possível observar uma grande variabilidade fenotípica dos isolados, havendo diferença significativa para seis dentre as oito características avaliadas. Esses resultados indicam que existe grande variabilidade entre os 67 isolados avaliados e demonstram a presença de comunidades bacterianas distintas habitando o sistema radicular e o solo rizosférico de T. spicatus na Caatinga.bitstream/item/72537/1/Boleti-de-pesquisa-98.pd

The membrane depolarization and increase intracellular calcium level produced by silver nanoclusters are responsible for bacterial death

This work highlights how our silver ultra nanoclusters (ARGIRIUM-SUNc) hand-made synthesized, are very useful as a bactericide and anti-biofilm agent. The Argirium-SUNc effective antibacterial concentrations are very low (< 1 ppm) as compared to the corresponding values reported in the literature. Different bacterial defense mechanisms are observed dependent on ARGIRIUM-SUNc concentrations. Biochemical investigations (volatilome) have been performed to understand the pathways involved in cell death. By using fluorescence techniques and cell viability measurements we show, for the first time, that membrane depolarization and calcium intracellular level are both primary events in bacteria death. The ARGIRIUM-SUNc determined eradication of different biofilm at a concentration as low as 0.6 ppm. This suggests that the effect of the nanoparticles follows a common mechanism in different bacteria. It is highly probable that the chemical constitution of the crosslinks could be a key target in the disrupting mechanism of our nanoparticles. Since the biofilms and their constituents are essential for bacterial survival in contact with humans, the silver nanoparticles represent a logical target for new antibacterial treatments

Enhanced nonlinear emission from single multilayered metal–dielectric nanocavities resonating in the near-infrared

Harmonic generation mechanisms are of great interest in nanoscience and nanotechnology, since they allow generating visible light by using near-infrared radiation, which is particularly suitable for its countless applications in bionanophotonics and optoelectronics. In this context, multilayer metal–dielectric nanocavities are widely used for light confinement and waveguiding at the nanoscale. They exhibit intense and localized resonances that can be conveniently tuned in the near-infrared and are therefore ideal for enhancing nonlinear effects in this spectral range. In this work, we experimentally investigate the nonlinear emission properties of multilayer metal–dielectric nanocavities. By engineering their absorption efficiency and exploiting their intrinsic interface-induced symmetry breaking, we achieve an almost 2 orders of magnitude higher second-harmonic generation efficiency compared to gold nanostructures featuring the same geometry and optical resonant behavior. In particular, while both the third-order nonlinear susceptibility and conversion efficiency are comparable with those of the Au nanoresonators, we estimate a second-order nonlinear susceptibility of the order of 1 pm/V, which is comparable with that of typical nonlinear crystals. We envision that our system, which combines the advantages of both plasmonic and dielectric materials, might enable the realization of composite and multifunctional nanosystems for the efficient manipulation of nonlinear optical processes at the nanoscale

Resultados Projeto AgroEcoBV: tecnologias de manejo agroecológico em pequenas propriedades no entorno de Boa Vista.

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Once-a-week or every-other-day urethra-sparing prostate cancer stereotactic body radiotherapy, a randomized phase II trial: 18 months follow-up results

Background To present the 18 months results from a prospective multicenter phase II randomized trial of short vs protracted urethra-sparing stereotactic body radiotherapy (SBRT) for localized prostate cancer (PCa).Methods Between 2012 and 2015, a total of 170 PCa patients were randomized to 36.25 Gy in 5 fractions (6.5 Gy x 5 to the urethra) delivered either every other day (EOD, arm A, n = 84) or once a week (QW, arm B, n = 86). Genitourinary (GU) and gastrointestinal (GI) toxicity (CTCAE v4.0 scale), IPSS, and QoL scores were assessed at baseline, at the 5th fraction (5fx), 12th weeks (12W), and every 6 months after SBRT. The primary endpoint was biochemical control at 18 months and grade >= 3 toxicity (including grade >= 2 for urinary obstruction/retention) during the first 3 months.Results Among the 165 patients analyzed, the toxicity stopping rule was never activated during the acute phase. Maximum acute grade 2 GU toxicity rates at 5fx were 17% and 19% for arms A and B, respectively, with only 2 cases of grade 2 GI toxicity at 5fx in arm A. At month 18, grade >= 2 GU and GI toxicity decreased below 5% and 2% for both arms. No changes in EORTC QLQ-PR25 scores for GU, GI, and sexual domains were observed in both arms between baseline and month 18. Four biochemical failures were observed, 2 in each arm, rejecting the null hypothesis of an unfavorable response rate = 95% rate.Conclusions At 18 months, urethra-sparing SBRT showed a low toxicity profile, with minimal impact on QoL and favorable biochemical control rates, regardless of overall treatment time (EOD vs QW)

First in-human radiation dosimetry of the gastrin-releasing peptide (GRP) receptor antagonist (68)Ga-NODAGA-MJ9.

Gastrin-releasing peptide receptor antagonists have promise in theranostics of several highly incident tumours, including prostate and breast. This study presents the first human dosimetry of <sup>68</sup> Ga-NODAGA-MJ9 in the first five consecutive patients with recurrent prostate cancer included in a dual-tracer positron emission tomography (PET) protocol. Five male patients with biochemical relapse of prostate adenocarcinoma underwent four whole-body time-of-flight PET/CT scans within 2 h after tracer injection. To be used as input in OLINDA/EXM 2.0, time-integrated activity coefficients were derived from manually drawn regions of interest over the following body regions: brain, thyroid, lungs, heart, liver, gallbladder, spleen, stomach, kidneys, adrenals, red marrow, pancreas, intestines, urinary bladder and whole body. Organ absorbed doses and effective dose (ED) were calculated with OLINDA/EXM 2.0 using the NURBS voxelized phantoms adjusted to the ICRP-89 organ masses and ICRP103 tissue-weighting factors. Additional absorbed dose estimations were performed with OLINDA/EXM 1.1 to be comparable with similar previous publications. The body regions receiving the highest absorbed doses were the pancreas, the urinary bladder wall, the small intestine and the kidneys (260, 69.8, 38.8 and 34.8 μGy/MBq respectively). The ED considering a 30-min urinary voiding cycle was 17.6 μSv/MBq in male patients. The increment of voiding time interval produced a significant increase of absorbed doses in bladder, prostate and testes, as well as an increase of ED. ED also increased if calculated with OLINDA/EXM 1.1. These results have been discussed in view of similar publications on bombesin analogues or on other commonly used theranostic peptides. The pancreas is the most irradiated organ after the injection of <sup>68</sup> Ga-NODAGA-MJ9, followed by the urinary bladder wall, the small intestine and the kidneys. ED is in the same range of other common <sup>68</sup> Ga-labelled peptides. Differences with similarly published studies on bombesin analogues exist, and are mainly dependent on the methodology used for absorbed dose calculations. Clinicaltrial.Gov identifier: NCT02111954 , posted on 11/042014