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A Hidden Complication of Pigtail Catheter Insertion
Pigtail catheters have emerged as an effective and less morbid alternative to traditional chest tubes for evacuation of pleural air. Rare complications in the literature have been reported. We report a case of a 92-year-old male who presented with dyspnea and shock, noted to have a pneumothorax requiring tube thoracostomy. Computed tomography demonstrated pigtail within the lung parenchyma. We discuss the implications of this occurrence
Topological Line Defects around Graphene Nanopores for DNA Sequencing
Topological line defects in graphene represent an ideal way to produce highly
controlled structures with reduced dimensionality that can be used in
electronic devices. In this work we propose using extended line defects in
graphene to improve nucleobase selectivity in nanopore-based DNA sequencing
devices. We use a combination of QM/MM and non-equilibrium Green's functions
methods to investigate the conductance modulation, fully accounting for solvent
effects. By sampling over a large number of different orientations generated
from molecular dynamics simulations, we theoretically demonstrate that
distinguishing between the four nucleobases using line defects in a
graphene-based electronic device appears possible. The changes in conductance
are associated with transport across specific molecular states near the Fermi
level and their coupling to the pore. Through the application of a specifically
tuned gate voltage, such a device would be able to discriminate the four types
of nucleobases more reliably than that of graphene sensors without topological
line defects.Comment: 6 figures and 6 page
Magnetic field decay in black widow pulsars
We study in this work the evolution of the magnetic field in 'redback-black widow' pulsars. Evolutionary calculations of these 'spider' systems suggest that first the accretion operates in the redback stage, and later the companion star ablates matter due to winds from the recycled pulsar. It is generally believed that mass accretion by the pulsar results in a rapid decay of the magnetic field when compared to the rate of an isolated neutron star. We study the evolution of the magnetic field in black widow pulsars by solving numerically the induction equation using the modified Crank-Nicolson method with intermittent episodes of mass accretion on to the neutron star. Our results show that the magnetic field does not fall below a minimum value ('bottom field') in spite of the long evolution time of the black widow systems, extending the previous conclusions for much younger low-mass X-ray binary systems. We find that in this scenario, the magnetic field decay is dominated by the accretion rate, and that the existence of a bottom field is likely related to the fact that the surface temperature of the pulsar does not decay as predicted by the current cooling models. We also observe that the impurity of the pulsar crust is not a dominant factor in the decay of magnetic field for the long evolution time of black widow systems.Instituto de Astrofísica de La Plat
Beyond the “resprout or not resprout” dichotomy: on the prevalence and evolutionary fingerprint of resprouting in tropical dry forest trees
A Decision Support System Based on Artificial Neural Networks for Pulmonary Tuberculosis Diagnosis
Global genetic diversity of var2csa in Plasmodium falciparum with implications for malaria in pregnancy and vaccine development
Malaria infection during pregnancy, caused by the sequestering of Plasmodium falciparum parasites in the placenta, leads to high infant mortality and maternal morbidity. The parasite-placenta adherence mechanism is mediated by the VAR2CSA protein, a target for natural occurring immunity. Currently, vaccine development is based on its ID1-DBL2Xb domain however little is known about the global genetic diversity of the encoding var2csa gene, which could influence vaccine efficacy. In a comprehensive analysis of the var2csa gene in >2,000 P. falciparum field isolates across 23 countries, we found that var2csa is duplicated in high prevalence (>25%), African and Oceanian populations harbour a much higher diversity than other regions, and that insertions/deletions are abundant leading to an underestimation of the diversity of the locus. Further, ID1-DBL2Xb haplotypes associated with adverse birth outcomes are present globally, and African-specific haplotypes exist, which should be incorporated into vaccine design
Antiprotozoal activity of the cyclopalladated complexes against leishmania amazonensis and trypanosoma cruzi
The present study describes the antiprotozoal activities of four cyclopalladated compounds, [Pd(dmba)(μ-Cl)]2, [Pd(dmba)(NCO)(isn)], [Pd(dmba)(N3)(isn)] and [Pd(dmba)(μ-NCO)]2, (dmba: N,N'-dimethylbenzylamine and isn: isonicotinamide), against the diseases leishmaniasis (Leishmania amazonensis and Leishmania infantum), Chagas disease (Trypanosoma cruzi) and human African trypanosomiasis (Trypanosoma brucei). [Pd(dmba)(μ-NCO)]2 exhibited good leishmanicidal and trypanocidal activities against L. amazonensis and T. cruzi intracellular amastigote forms, with a 50% inhibitory concentration (IC50) value of less than 9 µM and selectivity indexes of 14.47 and 28.42, respectively. Stability essays were conducted in phosphate buffer saline (PBS) pH 7.0 and showed that [Pd(dmba)(μ-NCO)]2 is the most stable molecule. These findings indicate that this compound presented higher selectivity for these parasites than the other tested compounds. The data presented here suggest that this compound should be considered in the development of new and more potent drugs for the treatment of leishmaniasis and Chagas disease27610321039COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPSem informação201308248-
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