Echelle Spectroscopy of gamma-ray binary 1FGL J1018.6-5856

We observed the Fermi-discovered gamma-ray binary 1FGL J1018.6-5856 at 20 epochs over 50 days using the CHIRON spectrograph, obtaining spectra at R~25,000 covering 4090-8908A. The average spectrum confirms an O6 V((f)) spectral type and extinction E(B-V) = 1.35+/-0.04. Variable absorption line equivalent widths suggest substantial contamination by wind line features. The limited S/N ratio hindered accurate continuum definition and prevented measurement of a high quality radial velocity curve. Nevertheless, the best data indicate a radial velocity amplitude <40 km/s for the He II lines and substantially lower for H I. We argue that this indicates a most likely compact object mass <2.2Msun. While black hole solutions are not excluded, a neutron star source of the gamma-ray emission seems preferred.Comment: 5 figures. To appear in the Astrophysical Journa

Unilateral congenital non-syndromic retinal vessel dilation and tortuosity

Purpose: To present a case of atypical unilateral developmental retinal vascular anomaly. Observations: A 10-year-old girl presented to her paediatrician after an absent red reflex was noted in a photograph. She had right anisometropic amblyopia and right iris heterochromia, but was otherwise healthy, with no visual complaints. Fundus examination revealed abnormal right retinal vasculature in keeping with an arteriovenous malformation (AVM). OCTA performed at age 16, showed large aberrant veins in the right eye, whereas OCTA B-Scans showed that the same eye had significantly higher retinal blood perfusion than the unaffected eye. Conclusions and Importance: OCTA is a valuable, non-invasive emerging method of evaluating patients with AVMs, with this patient having a unique unilateral presentation of a developmental anomaly, without evidence of progression or other vessel malformation. OCTA allowed assessment of flow between the affected and non-affected eye, quantifying the greater blood perfusion in the affected eye due to the AVM

The Post-Pericenter Evolution of the Galactic Center Source G2

In early 2014 the fast-moving near-infrared source G2 reached its closest approach to the supermassive black hole Sgr A* in the Galactic Center. We report on the evolution of the ionized gaseous component and the dusty component of G2 immediately after this event, revealed by new observations obtained in 2015 and 2016 with the SINFONI integral field spectrograph and the NACO imager at the ESO VLT. The spatially resolved dynamics of the Br$\gamma$ line emission can be accounted for by the ballistic motion and tidal shearing of a test-particle cloud that has followed a highly eccentric Keplerian orbit around the black hole for the last 12 years. The non-detection of a drag force or any strong hydrodynamic interaction with the hot gas in the inner accretion zone limits the ambient density to less than a few 10$^3$ cm$^{-3}$ at the distance of closest approach (1500 $R_s$), assuming G2 is a spherical cloud moving through a stationary and homogeneous atmosphere. The dust continuum emission is unresolved in L'-band, but stays consistent with the location of the Br$\gamma$ emission. The total luminosity of the Br$\gamma$ and L' emission has remained constant to within the measurement uncertainty. The nature and origin of G2 are likely related to that of the precursor source G1, since their orbital evolution is similar, though not identical. Both object are also likely related to a trailing tail structure, which is continuously connected to G2 over a large range in position and radial velocity.Comment: 17 pages, 12 figures; accepted for publication in Ap

Os créditos de titularidade de instituições financeiras nos processos de insolvência e de falência e recuperação judicial de empresas: análise dos conceitos vigentes há quinze anos nos ordenamentos jurídicos de Portugal e do Brasil

- Divulgação dos SUMÁRIOS das obras recentemente incorporadas ao acervo da Biblioteca Ministro Oscar Saraiva do STJ. Em respeito à Lei de Direitos Autorais, não disponibilizamos a obra na íntegra.- Localização na estante: 347.736(81:469) F178c- Coordenado por: Ivo Waiberg, José Horacio H. R. Ribeiro e Marcelo Barbosa Sacramone

COVID-19 in solid organ transplantation patients: A systematic review

Coronavirus disease (COVID-19) rapidly progresses to severe acute respiratory syndrome. This review aimed at collating available data on COVID-19 infection in solid organ transplantation (SOT) patients. We performed a systematic review of SOT patients infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The MEDLINE and PubMed databases were electronically searched and updated until April 20, 2020. The MeSH terms used were ‘‘COVID-19’’ AND ‘‘Transplant.’’ Thirty-nine COVID-19 cases were reported among SOT patients. The median interval for developing SARS-CoV-2 infection was 4 years since transplantation, and the fatality rate was 25.64% (10/39). Sixteen cases were described in liver transplant (LT) patients, and the median interval since transplantation was 5 years. The fatality rate among LT patients was 37.5% (6/16), with death occurring more than 3 years after LT. The youngest patient who died was 59 years old; there were no deaths among children. Twenty-three cases were described in kidney transplant (KT) patients. The median interval since transplantation was 4 years, and the fatality rate was 17.4% (4/23). The youngest patient who died was 71 years old. Among all transplant patients, COVID-19 had the highest fatality rate in patients older than 60 years : LT, 62.5% vs 12.5% (p=0.006); KT 44.44% vs 0 (p=0.039); and SOT, 52.94% vs 4.54% (p=0.001). This study presents a novel description of COVID-19 in abdominal SOT recipients. Furthermore, we alert medical professionals to the higher fatality risk in patients older than 60 years. (PROSPERO, registration number= CRD42020181299

Revealing new perspectives on the regulation of gene expression by the trans-splicing mechanism in Shistosoma mansoni.

Schistosomiasis is the second most prevalent neglected tropical disease caused by a Trematode flatworm from the genus Schistosoma. Schistosomes possess a complex life cycle requiring numerous and intricate mechanisms to rule transcriptional and post-transcriptional gene regulation. Thus, it is believed that spliced leader (SL) trans-splicing could play an important role in the parasite biology. The purpose of this study was is to shed light on the function of the trans-splicing mechanism in S. mansoni by searching gene categories that could be target of this process and attempting to silence transcripts harboring the SL sequence. Here, we analyze different life stages cDNA libraries enriched on SL-transcripts of S. mansoni. Our results show that, contrary to previous hypothesis, trans-spliced transcripts are associated to specific gene categories, such as carbohydrate metabolic process, RNA metabolism and DNA repair. Several trans-spliced transcripts were verified in at least two different stages of the S. mansoni life cycle. The marjority of the SL-transcripts are shared among males, females and mixed-sex adults, being followed by SL-transcripts shared by all adults and schistosomula. Among the analyzed life stages, the one presenting the lower number of shared genes is the egg. The results also reveal a set of SL-transcripts that are observed only in one stage of the life cycle and could represent transcripts that undergo stage-specific trans-splicing. Finally, we demonstrated that trans-splicing knockdown in sprocysts caused a reduction on the levels of all tested trans-spliced transcripts, but surprisingly the only phenotypic effect observed was a diminished larvae size. Financial support: CNPq, FAPEMIGX-MEETING 2011

Microarray analysis of gene expression induced by sexual contact in Schistosoma mansoni

<p>Abstract</p> <p>Background</p> <p>The parasitic trematode <it>Schistosoma mansoni </it>is one of the major causative agents of Schistosomiasis, a disease that affects approximately 200 million people, mostly in developing countries. Since much of the pathology is associated with eggs laid by the female worm, understanding the mechanisms involved in oogenesis and sexual maturation is an important step towards the discovery of new targets for effective drug therapy. It is known that the adult female worm only develops fully in the presence of a male worm and that the rates of oviposition and maturation of eggs are significantly increased by mating. In order to study gene transcripts associated with sexual maturation and oviposition, we compared the gene expression profiles of sexually mature and immature parasites using DNA microarrays.</p> <p>Results</p> <p>For each experiment, three amplified RNA microarray hybridizations and their dye swaps were analyzed. Our results show that 265 transcripts are differentially expressed in adult females and 53 in adult males when mature and immature worms are compared. Of the genes differentially expressed, 55% are expressed at higher levels in paired females while the remaining 45% are more expressed in unpaired ones and 56.6% are expressed at higher levels in paired male worms while the remaining 43.4% are more expressed in immature parasites. Real-time RT-PCR analysis validated the microarray results. Several new maturation associated transcripts were identified. Genes that were up-regulated in single-sex females were mostly related to energy generation (i.e. carbohydrate and protein metabolism, generation of precursor metabolites and energy, cellular catabolism, and organelle organization and biogenesis) while genes that were down-regulated related to RNA metabolism, reactive oxygen species metabolism, electron transport, organelle organization and biogenesis and protein biosynthesis.</p> <p>Conclusion</p> <p>Our results confirm previous observations related to gene expression induced by sexual maturation in female schistosome worms. They also increase the list of <it>S. mansoni </it>maturation associated transcripts considerably, therefore opening new and exciting avenues for the study of the conjugal biology and development of new drugs against schistosomes.</p

Liver transplant after SARS-CoV-2 infection: A systematic review

Background: The Coronavirus&nbsp;19 (COVID-19) pandemic has dramatically impacted liver organ transplantation. The American Society of Transplantation recommends a minimum of&nbsp;28&nbsp;days after symptom resolution for organ donation. However, the exact time for transplantation for recipients is unknown. Considering that mortality on the waiting list for patients with MELD&nbsp;&gt;25 or fulminant hepatitis is higher than that of COVID-19, the best time for surgery after SARS-CoV-2 infection remains undetermined. This study aims to expand the current knowledge regarding the Liver Transplantation (LT) time for patients after COVID-19 and to provide transplant physicians with essential decision-making tools to manage these critically ill patients during the pandemic. Methods: Systematic review of patients who underwent liver transplantation after diagnosis of COVID-19. The MEDLINE, PubMed, Cochrane, Lilacs, Embase, and Scielo databases were searched until June&nbsp;20, 2021. The MESH terms used were “COVID-19” and “Liver transplantation”. Results: 558&nbsp;articles were found; of these&nbsp;13&nbsp;articles and a total of&nbsp;18&nbsp;cases of COVID-19 prior to liver transplantation were reported. The mean age was&nbsp;38.7±14.6, with male prevalence. Most had mild symptoms of COVID. Five patients have specific treatment for COVID-19 with convalescent plasm or remdesivir/oseltamivir, just one patient received hydroxychloroquine, and 12&nbsp;patients received only symptomatic treatment. The median time between COVID-19 to LT was&nbsp;19&nbsp;days (13.5‒44.5). Deceased donor liver transplantation accounted for&nbsp;61% of cases, while living donor transplantation was&nbsp;39%. Conclusion: Despite the concerns regarding the postoperative evolution, the mortality of patients with high MELD or fulminant hepatitis transplanted shortly after COVID-19 diagnosis does not seem to be higher. (PROSPERO, registration number&nbsp;=&nbsp;CRD42021261790

Optical Distortion in the NACO Imager

In this research note, we present a set of distortion solutions that may be used to correct geometric optical distortion in images taken with the S13 camera of the NACO adaptive optics imager.Comment: published in the RNAA

Foliar lead uptake by lettuce exposed to atmospheric fallouts

Metal uptake by plants occurs by soil−root transfer but also by direct transfer of contaminants from the atmosphere to the shoots. This second pathway may be particularly important in kitchen gardens near industrial plants. The mechanisms of foliar uptake of lead by lettuce (Lactuca sativa) exposed to the atmospheric fallouts of a lead-recycling plant were studied. After 43 days of exposure, the thoroughly washed leaves contained 335 ± 50 mg Pb kg−1 (dry weight). Micro-X-ray fluorescence mappings evidenced Pb-rich spots of a few hundreds of micrometers in diameter located in necrotic zones. These spots were more abundant at the base of the central nervure. Environmental scanning electron microscopy coupled with energy dispersive X-ray microanalysis showed that smaller particles (a few micrometers in diameter) were also present in other regions of the leaves, often located beneath the leaf surface. In addition, submicrometric particles were observed inside stomatal openings. Raman microspectrometry analyses of the leaves identified smelter-originated Pb minerals but also secondary phases likely resulting from the weathering of original particles. On the basis of these observations, several pathways for foliar lead uptake are discussed. A better understanding of these mechanisms may be of interest for risk assessment of population exposure to atmospheric metal contamination