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Study question Could new molecules like Lonomia obliqua lipocalins and hemolins have cytoprotective effects on endometrial stem cells (hESC)? Summary answer Lonomia obliqua venom-induced hESC viability, proliferation and migration occurred mainly by protection against oxidative damage and ERK-dependent pathway activation What is known already Recurrent pregnancy loss (RPL) is associated with severe physical and psychological morbidity, for which there is no treatment options. The pathophysiology involves deficiency in proliferation and migration capacities of endometrial stromal cells (hESCs) impairing embryo implantation and development. Animal venoms are rich sources of bioactive molecules and despite its known toxic effects, they also have protective components such as pro-proliferative molecules, growth factor-like, anti-apoptotic and anti-oxidant. Study design, size, duration This study was an experimental in vitro with endometrial stem cells. Treatment duration was 8–72h. Every assay had control cells exposed to phosphate buffered saline (PBS). Participants/materials, setting, methods hESCs were isolated from fresh human endometrial biopsies and characterized according standard protocols. Then the effects of L. obliqua venomous secretions on cell viability, proliferation and migration were determined using MTT, wound-healing assay, sulforhodamine B (SRB) assay and measuring the immunocontent of Ki67. Venom components involved in cell enhancing effects were also identified by classical chromatographic methods and proteomic analysis. Assays were conducted in triplicate. Main results and the role of chance The hESCs in culture showed adhesiveness properties, presented a fusiform fibroblastoid morphology and ability to in vitro differentiate into adipocytes, osteocytes and chondrocytes. The expression of cell surface markers was also characterized by flow cytometry. hESCs were positive for mesenchymal markers (CD105, CD90 and CD73) and negative for hematopoietic markers (CD45 and CD11), indicating that isolated cells have potential for multilineage differentiation. L. obliqua bristle extract (LOBE) increased dose-dependently hESCs viability in a concentration range varying from 0.001 to 0.1 µg/mL, independently of the cell isolation bath. For some cell isolates (patient ID 1, 3, 4, 6 and 7) it was observed a slightly reduction in hESC viability at highest LOBE concentrations (10 µg/mL). Treatment increased hESC viability in the presence of low concentrations of fetal bovine serum (1% FBS) and even in its complete absence. This effect was long lasting, being significant up to 72 h of incubation with LOBE in serum deprivation conditions. r to identify the potential molecules involved in the cytoprotective action, a mass spectrometry-based proteomic analysis was performed. It was identified a total number of 430 proteins in LOBE and 312 proteins in L. obliqua hemolymph. Limitations, reasons for caution This study was only conducted in vitro. Wider implications of the findings: In this work we reported the identification of at least six protein classes with cytoprotective properties through proteomic analysis and isolated one fraction enriched in this cytoprotective factors. L. obliqua secretions induced increase in hESCs viability, proliferation and migration mainly by the protection against oxidative damage and ERK-dependent pathway activation. Trial registration number Not applicable

Scanning tunnelling microscopy overshadowed other microscopy techniques owing to its unprecedented spatial resolution. However, the lack of secondary electrons in the experiment always motivated the quest for a complementary technique. The topografiner technology - a precursor of the STM - could not meet this task so far. Nevertheless, it still plays an important role in the arsenal of probing techniques. In this report, we present secondary-electron distributions of low-energy primary electrons directed at a cleaved GaAs(110) surface and preliminary measurements of single-energy surface imaging in a hybrid experiment.

In Scanning Tunnelling Microscopy (STM) the electrons are confined within the tunneling region, and this limitation has redirected scientists to alternative microscopy techniques, aimed at extracting the electrons away from the tunneling region. The topografiner - strictly speaking a precursor of STM, originally developed at the National Bureau of Standards - is an example. In this paper we report on the latest improvements of the topografiner technology that allow resolving topographic contrast with a lateral resolution down to 7 A.

The paramagnetic-to-ferromagnetic phase transition is classified as a critical phenomenon due to the power-law behaviour shown by thermodynamic observables when the Curie point is approached. Here we report the observation of such a behaviour over extraordinarily many decades of suitable scaling variables in ultrathin Fe films, for certain ranges of temperature T and applied field B. This despite the fact that the underlying critical point is practically unreachable because protected by a phase with a modulated domain structure, induced by the dipole–dipole interaction. The modulated structure has a well-defined spatial period and is realized in a portion of the (T, B) plane that extends above the putative critical temperature, where thermodynamic quantities do not display any singularity. Our results imply that scaling behaviour of macroscopic observables is compatible with an avoided critical point., Nature Communications, 7, ISSN:2041-1723

Recent experiments report the current (I) versus voltage (V) characteristics of a tunnel junction consisting of a metallic tip placed at a distance d from a planar electrode, d varying over six orders of magnitude, from few nanometres to few millimetres. In the ‘electric-field-assisted’ (or ‘field emission’) regime, as opposed to the direct tunnelling regime used in conventional scanning tunnelling microscopy, all I–V curves are found to collapse onto one single graph when d is suitably rescaled, suggesting that the current I=I(V,d) is in reality a generalized homogeneous function of one single variable, i.e. 𝐼���=ℐ(𝑉���⋅𝑑���−λ), where λ being some characteristic exponent and ℐ(𝑥���) being a scaling function. In this paper, we provide a comprehensive explanation—based on analytical arguments, numerical simulations and further experimental results—for the scaling behaviour that we show to emerge for a variety of tip–plane geometries and thus seems to be a general feature of electric-field-assisted tunnelling., Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences, 470 (2167), ISSN:1364-5021, ISSN:1471-2946, ISSN:0080-4630, ISSN:0950-1207

Nature Communications 7: Article number: 13611 (2016); Published 5 December 2016; Updated 17 January 2017 The original version of this Article contained a typographical error in the spelling of the author S.A. Cannas, which was incorrectly given as S. Cannas. This has now been corrected in both the PDF and HTML versions of the Article.

We measure the current vs voltage (I-V) characteristics of a diodelike tunnel junction consisting of a sharp metallic tip placed at a variable distance d from a planar collector and emitting electrons via electric-field assisted emission. All curves collapse onto one single graph when I is plotted as a function of the single scaling variable Vd^{-\lambda}, d being varied from a few mm to a few nm, i.e., by about six orders of magnitude. We provide an argument that finds the exponent {\lambda} within the singular behavior inherent to the electrostatics of a sharp tip. A simulation of the tunneling barrier for a realistic tip reproduces both the scaling behavior and the small but significant deviations from scaling observed experimentally., Comment: 6 pages, 6 figures. Accepted for publication in Physical Review B

We have measured the voltage vs distance V - d characteristics at constant current I of a tunnel junction consisting of an electron emitting sharp tip placed at a variable distance d from a planar anode. At sufficiently large distances, i.e. in the regime of electric field assisted quantum tunneling, the V - d characteristics for different currents follow approximately a power law V ∝ dλ, the exponent λ being independent of the current. Here we compare and discuss the origin of the observed power law and the measured value of λ in terms of electrostatic properties of the tip-plane junction, taking the geometry of the tip as a hyperboloid of revolution.

The topografiner technology, developed originally at the National Bureau of Standards (now National Institute of Standards and Technology) with the aim of measuring the surface micro-topography, is less widespread than scanning tunneling microscopy but has a remarkable property: the electrons can escape the tip-surface junction. We have recently used topografiner imaging to map the surface of various metals and semiconductors with (almost) nanometer lateral spatial resolution. In this paper, we describe our attempt to endowing the NIST topografiner with an energy analysis of the electrons escaping the junction, with the aim of performing spectroscopy with nanometer spatial resolution.

We perform scanning tunnelling microscopy (STM) in a regime where primary electrons are field-emitted from the tip and excite secondary electrons out of the target—the scanning field-emission microscopy regime (SFM). In the SFM mode, a secondary-electron contrast as high as 30% is observed when imaging a monoatomic step between a clean W(110)- and an Fe-covered W(110)-terrace. This is a figure of contrast comparable to STM. The apparent width of the monoatomic step attains the 1 nm mark, i.e. it is only marginally worse than the corresponding width observed in STM. The origin of the unexpected strong contrast in SFM is the material dependence of the secondary-electron yield and not the dependence of the transported current on the tip–target distance, typical of STM: accordingly, we expect that a technology combining STM and SFM will highlight complementary aspects of a surface while simultaneously making electrons, selected with nanometre spatial precision, available to a macroscopic environment for further processing., Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences, 472 (2195), ISSN:1364-5021, ISSN:1471-2946, ISSN:0080-4630, ISSN:0950-1207

In Near Field-Emission Scanning Electron Microscopy the source of the primary beam is only few tens nm away from the target. We report the progress in primary beam generation and compare the performance of the instrument in field emission mode with respect to the well-established Scanning Tunneling Microscopy (STM).

In a previous publication (Kirk, 2010) the experimental technique of imaging near-field emission scanning electron microscopy (NFESEM) imaging was introduced. In NFESEM, a sharp tip in positioned at distances of a few 10nm from a metallic surface. Above a threshold voltage, electrons are field emitted from the tip. The field-emitted current is used, while scanning the tip across the surface at a well-defined, constant distance, to generate a topographic image of the surface with subnanometer vertical spatial resolution and a few-nanometer lateral spatial resolution. In this review, we discuss the fundamental physical processes that occur in NFESEM and provide some quantitative results. It is our goal to provide sufficient background information to allow NFESEM-based instruments to be developed in other laboratories.

This case report demonstrates the use of thallium-201 (201Tl) scans versus iodine-131- (131l) anti-CEA F(ab')2 scans in a patient with high serum CEA levels due to metastases of medullary thyroid carcinoma in the suprarenal region and sacroiliacal region. Scintigraphy using monoclonal antibodies directed against CEA showed a higher tumor uptake (0.26% dose and 0.64% dose, respectively) than a thallium scan and is believed to be promising for future radiotherapeutic applications.