The ability of Salmonella to drill holes in the aorta.

A 56-year-old male with fever and enlarged mediastinum underwent examinations for lymphoma. He had back pain and hypotension. Computed tomography showed a false aneurysm of the aortic arch (Fig. 1a). Pathological aorta was excised. Reconstruction of the large hole on the aortic arch (Fig. 1b) with oval patch tailored from cryopreserved thoracic aorta was performed under hypothermic circulatory arrest. Blood and aortic cultures grew Salmonella. The patient had uneventful recovery. One year later is free from infection

Video-assisted cardioscopy for removal of primary left ventricular myxoma.

Left ventricular myxoma is a rare benign cardiac tumor. Surgical excision is the treatment of choice and completeness of removal is mandatory to avoid late recurrence. A case is presented in which aortic transvalvular video-assisted cardioscopy was used to facilitate removal

Port-Access cardiac surgery: from a learning process to the standard.

Background: Port-Access™ surgery has been one of the most innovative and controversial methods in the spectrum of minimally invasive techniques for cardiac operations and has been widely used for the treatment of several cardiac diseases. The technique was introduced in our center to evaluate its efficacy in reproducing standardized results without an additional risk. Methods: Endovascular cardiopulmonary bypass (CPB) through femoral access and endoluminal aortic occlusion were used in 129 patients for a variety of surgical procedures, all of which were video-assisted. A minimal (4-6 cm) anterior thoracotomy through the fourth intercostal space was used in all cases as the surgical approach. Results: More than 96% of the planned cases concluded as true Port-Access™ procedures. Mean CBP and crossclamp times were 87.2 min. ± 51.2 (range of 10-457) and 54.9 min. ± 30.6 (range of 10-190), respectively. Hospital mortality for the overall group was 1.5%, and mitral valve surgery had a 2.2% hospital death rate. The incidence of early neurological events was 0.7%. Mean extubation time, ICU stay, and total length of hospital stay were 5 hours ± 6 hrs. (range of 2-32), 12 hours ± 11.8 hrs. (range of 5-78), and 7 days ± 7.03 days (range of 1-72), respectively. Conclusions: Our experience indicates that the Port- Access™ technique is safe and permits reproduction of standardized results with the use of a very limited surgical approach. We are convinced that this is a superior procedure for certain types of surgery, including isolated primary or redo mitral surgery, repair of a variety of atrial septal defects (ASDs), and atrial tumors. It is especially useful in high-risk patients, such as elderly patients or those requiring reoperation. Simplification of the procedure is nevertheless desirable in order to further reduce the time of operation and to address other drawbacks

Quantum interference and Klein tunneling in graphene heterojunctions

The observation of quantum conductance oscillations in mesoscopic systems has traditionally required the confinement of the carriers to a phase space of reduced dimensionality. While electron optics such as lensing and focusing have been demonstrated experimentally, building a collimated electron interferometer in two unconfined dimensions has remained a challenge due to the difficulty of creating electrostatic barriers that are sharp on the order of the electron wavelength. Here, we report the observation of conductance oscillations in extremely narrow graphene heterostructures where a resonant cavity is formed between two electrostatically created bipolar junctions. Analysis of the oscillations confirms that p-n junctions have a collimating effect on ballistically transmitted carriers. The phase shift observed in the conductance fringes at low magnetic fields is a signature of the perfect transmission of carriers normally incident on the junctions and thus constitutes a direct experimental observation of ``Klein Tunneling.''Comment: 13 pages and 6 figures including supplementary information. The paper has been modified in light of new theoretical results available at arXiv:0808.048

Quantum and classical confinement of resonant states in a trilayer graphene Fabry-Pérot interferometer

The advent of few-layer graphene has given rise to a new family of two-dimensional systems with emergent electronic properties governed by relativistic quantum mechanics. The multiple carbon sublattices endow the electronic wavefunctions with pseudospin, a lattice analogue of the relativistic electron spin, whereas the multilayer structure leads to electric-field-effect tunable electronic bands. Here we use these properties to realize giant conductance oscillations in ballistic trilayer graphene Fabry-Pérot interferometers, which result from phase coherent transport through resonant bound states beneath an electrostatic barrier. We confine these states by selectively decoupling them from the leads, resulting in transport via non-resonant states and suppression of the giant oscillations. The confinement is achieved both classically, by manipulating quasiparticle momenta with a magnetic field, and quantum mechanically, by locally varying the pseudospin character of the carrier wavefunctions. Our results illustrate the unique potential of trilayer graphene as a versatile platform for electron optics and pseudospintronics.United States. Office of Naval Research (GATE MURI)National Science Foundation (U.S.) (Career Award DMR-0845287)Conselho Nacional de Pesquisas (Brazil

Quantum and classical confinement of resonant states in a trilayer graphene Fabry-Pérot interferometer

The advent of few-layer graphene has given rise to a new family of two-dimensional systems with emergent electronic properties governed by relativistic quantum mechanics. The multiple carbon sublattices endow the electronic wavefunctions with pseudospin, a lattice analogue of the relativistic electron spin, whereas the multilayer structure leads to electric-field-effect tunable electronic bands. Here we use these properties to realize giant conductance oscillations in ballistic trilayer graphene Fabry-Pérot interferometers, which result from phase coherent transport through resonant bound states beneath an electrostatic barrier. We confine these states by selectively decoupling them from the leads, resulting in transport via non-resonant states and suppression of the giant oscillations. The confinement is achieved both classically, by manipulating quasiparticle momenta with a magnetic field, and quantum mechanically, by locally varying the pseudospin character of the carrier wavefunctions. Our results illustrate the unique potential of trilayer graphene as a versatile platform for electron optics and pseudospintronics.United States. Office of Naval Research (GATE MURI)National Science Foundation (U.S.) (Career Award DMR-0845287)Conselho Nacional de Pesquisas (Brazil

Drosophila TIEG Is a Modulator of Different Signalling Pathways Involved in Wing Patterning and Cell Proliferation

Acquisition of a final shape and size during organ development requires a regulated program of growth and patterning controlled by a complex genetic network of signalling molecules that must be coordinated to provide positional information to each cell within the corresponding organ or tissue. The mechanism by which all these signals are coordinated to yield a final response is not well understood. Here, I have characterized the Drosophila ortholog of the human TGF-β Inducible Early Gene 1 (dTIEG). TIEG are zinc-finger proteins that belong to the Krüppel-like factor (KLF) family and were initially identified in human osteoblasts and pancreatic tumor cells for the ability to enhance TGF-β response. Using the developing wing of Drosophila as “in vivo” model, the dTIEG function has been studied in the control of cell proliferation and patterning. These results show that dTIEG can modulate Dpp signalling. Furthermore, dTIEG also regulates the activity of JAK/STAT pathway suggesting a conserved role of TIEG proteins as positive regulators of TGF-β signalling and as mediators of the crosstalk between signalling pathways acting in a same cellular context

Comparison of salivary proteome of children with different sensitivities for bitter and sweet tastes: association with body mass index

Background/objectives: Oral sensorial perception is a key aspect in food choices and knowing the mechanisms modulating such perception is of major importance in the context of child obesity, which is reaching high rates in Mediterranean countries. Salivary proteome has been linked to taste sensitivity in adults. The aim of this study was to search for differences in salivary proteomes of children with different bitter or sweet taste sensitivities and to assess if these potential differences are associated with their body mass index percentile (BMI percentile). Subjects/methods: 387 children aged 8-9 years old were assessed for BMI percentile and classified according to their sensitivity to bitter and sweet tastes, according to their caffeine and sucrose detection thresholds, respectively. Saliva protein composition was compared among taste sensitivity groups, taking into account BMI percentile and gender, using gel-based proteomics approaches, coupled to mass spectrometry for protein identification. Results: Among the salivary proteins related to bitter taste sensitivity, higher levels of cystatins were observed in bitter-sensitive children, in the case of those of normal weight, and in bitter low-sensitive, in the case of overweight children. For sweetness, the relationship between saliva and taste perception was also dependent on BMI percentile, with several proteins (including salivary cystatins) differing between taste sensitivity groups, with disparities arising between normal-weight and overweight children. Cystatin isoforms A, B and SA were observed to be considerably increased in saliva from obese children. Conclusions: Salivary proteome is related with sensitivities to bitter and sweet tastes in children, but the association is dependent on BMI percentile and gender