LHRH-Conjugated Drugs as Targeted Therapeutic Agents for the Specific Targeting and Localized Treatment of Triple Negative Breast Cancer

Bulk chemotherapy and drug release strategies for cancer treatment have been associated with lack of specificity and high drug concentrations that often result in toxic side effects. This work presents the results of an experimental study of cancer drugs (prodigiosin or paclitaxel) conjugated to Luteinizing Hormone-Releasing Hormone (LHRH) for the specific targeting and treatment of triple negative breast cancer (TNBC). Injections of LHRH-conjugated drugs (LHRH-prodigiosin or LHRH-paclitaxel) into groups of 4-week-old athymic female nude mice (induced with subcutaneous triple negative xenograft breast tumors) were found to specifically target, eliminate or shrink tumors at early, mid and late stages without any apparent cytotoxicity, as revealed by in vivo toxicity and ex vivo histopathological tests. Our results show that overexpressed LHRH receptors serve as binding sites on the breast cancer cells/tumor and the LHRH-conjugated drugs inhibited the growth of breast cells/tumor in in vitro and in vivo experiments. The inhibitions are attributed to the respective adhesive interactions between LHRH molecular recognition units on the prodigiosin (PGS) and paclitaxel (PTX) drugs and overexpressed LHRH receptors on the breast cancer cells and tumors. The implications of the results are discussed for the development of ligand-conjugated drugs for the specific targeting and treatment of TNBC

Elasticity, strength, and refractive index of argon at high pressures

High-pressure Brillouin spectroscopy of polycrystalline argon, measured using two scattering angles (180° and 70°), determines the isotropic elastic moduli, shear strength, equation of state, and refractive index of face-centered-cubic argon from 1.3 to 30 GPa at room temperature. The index of refraction n=1.33-1.67 over this pressure range. An Eulerian finite-strain analysis (Birch-Murnaghan equation of state) yields an isothermal bulk modulus and pressure derivative KT =15.1 (±1.1) GPa and K′T =5.4 (±0.3) at 2 GPa. The resulting equation of state agrees well with previous x-ray diffraction measurements, illustrating the suitability of high-pressure Brillouin scattering for characterizing the elasticity and strength of polycrystalline materials.5 page(s

INFLUENCE OF CHEMICAL AND THERMAL TREATMENTS ON TENSILE STRENGTH OF FIBERS FROM SUGAR CANE BAGASSE AND BANANA TREE TRUNK

International audienceInterest in lignocellulosic by-products is important as they represent a cheap renewable resource with high potential for environmental friendly technologies. Regarding the applications either for bio-oil, animal feeding, paper, char or activated char production or chemicals recovering….., many treatments have been studied and optimized. These include : chemical, enzymatic, thermal, and hydrothermal treatments. Then, an important bibliography exists about the effect of the treatments on the chemical constituents of the fibers. Nevertheless, very few works relate the effect of the treatments on the mechanical properties of the fibers. Our purpose is the study of the effect of pyrolysis, alkaline and acid treatments on chemical composition, morphology and mechanical properties of the fibers. The two studied fibers, sugar cane bagasse and banana pseudo-stem fibers, present an increase of tensile strength after thermal treatment. At the contrary, the chemical attacks lead to a decrease of the strength. The preliminary results obtained for composite reinforced with the treated fibers also show best strength for composites made of pyrolyzed fibers. The mechanical results are not fully consistent with the tensile strength evolutions of fibers

An Investigation of Fatigue Crack Nucleation and Growth in a Ti–6Al–4V/TiB in Situ Composite

This paper presents the results of an experimental study of fatigue crack nucleation and growth in a Ti–6Al–4V/TiB in situ whisker-reinforced composite. The onset of crack nucleation is shown to correspond to ∼20% of the total life at a stress range of 480 MPa. This is associated with transverse cracking across TiB whiskers, and interfacial decohesion between the TiB whiskers and the Ti–6Al–4V matrix. Subsequent cracking occurs by the formation of multiple cracks across the elongated α grains. These cracks are retarded initially by the β phase. However, subsequent fatigue damage results in transgranular crack growth across α and β phases prior to the onset of catastrophic failure. The long fatigue crack growth rates in the Paris regime in the Ti–6Al–4V/TiB composite are comparable to those of Ti–6Al–4V processed under nominally identical conditions. However, the fatigue crack growth rates in the composite are faster than those in the matrix alloy at lower ΔK values. Cyclic deformation of the composite is associated with strain softening, presumably as a result of progressive interfacial decohesion around the TiB whiskers early in the fatigue deformation process. The implications of the results are assessed for potential structural applications of the Ti–6Al–4V/TiB composite

Dendrite growth in annealed polymer blends for use in bulk heterojunction solar cells

This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in Akogwu, Onobu, Wali Akande, Tiffany Tong, and Wole Soboyejo. "Dendrite growth in annealed polymer blends for use in bulk heterojunction solar cells." Journal of Applied Physics 110, no. 10 (2011): 103517. and may be found at http://dx.doi.org/10.1063/1.3652858This paper presents the evidence of growth of dendrites during the annealing of poly (3-hexylthiophene) and [6,6]-phenyl C61-butyric acid methyl ester (P3HT:PCBM) blends that are being explored for potential applications in bulk heterojunction polymer solar cells. These dendrites were observed in high resolution scanning electron microscopy to have morphologies that depend on the annealing temperature. Consistent with a recent eutectic phase diagram, the dendrites were not observed at 200 °C. The observations were explained by considering the effects of temperature on the kinetics of phase nucleation and growth in P3HT: PCBM blends. The implications of the results are also discussed for the stability of electrical properties in bulk heterojunction solar cells