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Glioblastoma is known as one of the most aggressive human cancers. To gain access of the brain, therapeutic agents must overcome blood-brain barrier (BBB). In this study, Cisplatin (Cispt)-loaded polybutylcyanoacrylate (PBCA) nanoparticles (NPs) were prepared through miniemulsion polymerization technique. They were coated with polysorbate 80 to cross the BBB of glioblastoma-bearing rats. Prepared NPs were characterized with respect to their size, size distribution, zeta potential, drug loading and encapsulation efficiency, cytotoxicity effects, drug release, and stability pattern. Size and zeta potential of nanodrug were found to be 489 nm and -20 mV, while drug loading and encapsulation efficiency were determined to be 5% and 25%, respectively. Release studies demonstrated high retention capability of nanodrug in that 3.18% of Cispt was released from NPs in a period of 51 h. NPs presented acceptable stability after 2 months and lyophilization. Mean survival time in nanodrug receivers was 19.6 days, while it was 17.5 days for free drug receivers. Histological studies demonstrated efficacy of PBCA NPs in reducing side effects. Finally, such preparation can be considered as a promising nanocarrier for other types of tumor.

Our study found a high prevalence of drug-resistant mutations in Iranian HIV-infected patients. Our data support the need for continued surveillance of resistance patterns to help guide therapeutic approaches and limit transmission of these variants.

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High density polyethylene/tricalcium phosphate/ultra high molecular weight polyethylene (TCP/HDPE/UHMWPE) Nanocomposite as an orthopedic biomaterial (with better properties toward TCP/HDPE composite) was obtained. To evaluate the capability of this nanocomposite as a material for bone tissue replacement, mechanical and biological assessments were performed. In this study, nanosize β‐TCP powders with average grain size of 100 nm were synthesized by chemical precipitation method and characterized by means of X‐ray diffraction (XRD), Fourier‐transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). To evaluate the mechanical properties of this biomaterial, tensile properties were obtained for the material. Results showed that by increasing the weight percentage of β‐TCP, the elastic modulus increases, elongation at yield decreases and with no significant change in tensile strength. SEM micrographs of cryogenic fracture surface of samples indicated that distribution of nano powders in matrix is homogeneous. In vitro biological evaluations on the samples were done by performing cytotoxicity (MTT assay), alkaline phosphatase enzyme, and cell attachment tests. In all of the tests, osteoblast cells were used. Results of biological tests showed that the samples are biocompatible and they have no toxicity. Also, SEM observations demonstrated that the cells can attach to surface of nanocomposite samples, which reveals osteoconductivity of the surface. POLYM. COMPOS., 31:1745–1753, 2010. © 2010 Society of Plastics Engineers.