We report combined therapy using upconversion nanoparticles (UCNP) coupled to two therapeutic agents: beta-emitting radionuclide yttrium-90 (90Y) fractionally substituting yttrium in UCNP, and a ...fragment of the exotoxin A derived from Pseudomonas aeruginosa genetically fused with a targeting designed ankyrin repeat protein (DARPin) specific to HER2 receptors. The resultant hybrid complex UCNP-R-T was tested using human breast adenocarcinoma cells SK-BR-3 overexpressing HER2 receptors and immunodeficient mice, bearing HER2-positive xenograft tumors. The photophysical properties of UCNPs enabled background-free imaging of the UCNP-R-T distribution in cells and animals. Specific binding and uptake of UCNP complexes in SK-BR-3 cells was observed, with separate 90Y- and PE40-induced cytotoxic effects characterized by IC50 140 μg/mL (UCNP-R) and 5.2 μg/mL (UCNP-T), respectively. When both therapeutic agents were combined into UCNP-R-T, the synergetic effect increased markedly, ∼2200-fold, resulting in IC50 = 0.0024 μg/mL. The combined therapy with UCNP-R-T was demonstrated in vivo.
The article presents an innovative approach to enhancing cement concrete, bordering on a scientific breakthrough, and explains it in a way that is easy to understand. The core concept is the ...integration of a reactive agent with a chemical fluid to augment the material and endow it with novel characteristics. The technique, as suggested by the author, involves utilizing lyophobic sols that they have formulated as admixtures, combined with aqueous solutions of chemical additives produced by Russian companies. Due to the inclusion of these Nanostructured sols in the chemical additives, heavy cement concrete treated in this manner shows remarkable resilience. It remains unaffected by repeated freeze-thaw cycles, even when immersed in saline or mineral-rich waters. Furthermore, this advanced concrete does not demand any special measures for protection, maintenance, or repair, nor does it require additional waterproofing.
The art and science of heterostructure design has not remained still since its founding: While the theoretical principles initially advanced rapidly, experimental realization initially lagged until ...the ideal AlGaAs solid solutions were found. From this point, development into application proceeded apace. In this Review, these intial steps and the current position of heterostructure applications are surveyed. New developments, such as the inclusion of quantum dots into heterostructures—with its concomitant world‐record threshold current for laser activity—and future challenges are also elucidated.
The “magic” mixture of AlGaAs was found in researchers in St. Petersburg and gave this group, headed by Alferov, a strong position in the implementation of solid‐state optoelectronics, such as the laser shown in the picture, and its leader a share of the 2000 Nobel prize for Physics. New technological developments—single‐electron devices and ever‐lower threshold currents for example—are also described.
The range of negative characteristic temperatures in temperature dependences of threshold current density of low-threshold (In, Ga)As/(Al, Ga)As quantum dot injection lasers has been observed. A ...model describing the decrease in threshold current density with temperature at low temperatures is proposed.
Antibody-photosensitizer chemical conjugates are used successfully to kill cancer cells in photodynamic therapy. However, chemical conjugation of photosensitizers presents several limitations, such ...as poor reproducibility, aggregation, and free photosensitizer impurities. Here, we report a fully genetically encoded immunophotosensitizer, consisting of a specific anti-p185HER⁻²⁻ECD antibody fragment 4D5scFv fused with the phototoxic fluorescent protein KillerRed. Both parts of the recombinant protein preserved their functional properties: high affinity to antigen and light activation of sensitizer. 4D5scFv-KillerRed showed fine targeting properties and efficiently killed p185HER⁻²⁻ECD-expressing cancer cells upon light irradiation. It also showed a remarkable additive effect with the commonly used antitumor agent cisplatin, further demonstrating the potential of the approach.
Authors report on the fabrication of quantum dot (QDs) heterostructures for applications in optoelectronics. Different kinds of QDs are currently used: (i) 3-D quantum dots obtained by ...Stranski-Krastanow or Volmer-Weber growth in the InAs-GaAs material system, (ii) 2-D-shaped QDs formed by submonolayer insertions in the InAs-GaAs and similar systems, (iii) GaAs QDs formed on a corrugated (311)A AlAs surface, (iv) and QDs obtained by spinodal decomposition and activated spinodal decomposition in InGaAs-GaAs and InGaAsN-GaAs material systems. Formation of uniformly sized and shaped QDs is possible in all of these approaches and is mostly governed by thermodynamics. Ultrahigh modal gain and giant optical nonlinearity can be achieved in dense arrays of small QDs. Long wavelength (1.3-1.6 mu m) emission can be achieved using large InAs QDs. Recent advances in growth have made possible the realization of GaAs 1.3 mu m continuous wave (CW) vertical-cavity surface-emitting lasers with approx 0.8 mW output power and long operation lifetime. 31 refs.
Quantum dot (QD) lasers have decisive advantages compared to
quantum well lasers. Zero-dimensional charge carrier localization
and reduction of charge carrier diffusion result in reduced
...non-radiative surface recombination and thus possibly reduced facet
overheating and larger catastrophic optical damage (COD) threshold,
crucial for high power operation. The emission wavelengths of
1100 nm–1300 nm are easily realized using QDs on GaAs substrate,
not available with traditional quantum wells of the same material
system. We present results on metal-organic chemical vapor phase
deposition (MOCVD) and molecular beam epitaxy (MBE) grown high power
QD lasers (up to 4 W front facet cw) based on InGaAs QDs on GaAs
substrate
Low threshold current density (AlInGa)As/GaAs lasers based on InGaAs quantum dots (QDs) are grown by metal organic chemical vapour deposition (MOCVD). Quantum dots deposited at 490° C and covered ...with GaAs are directly revealed in the active region. On a transmission electron microscopy (TEM) image of the laser structure no large clusters or dislocations are found over a macroscopic distance. We show that the properties of QD lasers can be strongly improved if the QDs are confined by Al
0.3
Ga
0.7
As barriers and the cladding layers are grown at high temperature. Optimisation of the laser structure geometry allows extension of the range of ultrahigh temperature stability (
T
0
=385 K) of the threshold current to 50° C.
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