[Intra-extra biosynthesis of gold nanoparticles by fungus rhizopus oryza]

Gold nanoparticles have found many applications in cancer diagnosis and therapy, drug and gene delivery and DNA and protein characterizations. Fungi are extremely good candidates in the synthesis of metal nanoparticles because of their ability to secrete large amounts of enzymes. The aim of this study was biosynthesis of gold nanoparticles by a fungus. The sampling was performed from the Ahar copper mine. The biomasses of isolated fungi were incubated with HAuCl[4] solution in a shaker-incubator for 72 hr, and the strains that were able to produce gold nanoparticles were identified. The production of gold nanoparticles was studied with UV-vis spectroscopy, X-ray diffraction [XRD] and transmission electron microscopy [TEM]. Among the eight types of fungi that were isolated from the Ahar copper mine, only Rhizopus oryza was able to synthesize gold nanoparticles. The synthesis of gold nanoparticles was confirmed by observing the characteristic peak at 540 nm using UV-vis spectroscopy. The XRD analysis confirmed that the produced gold nanoparticles are in the form of nanocrystaline. Transmission electron microscopy images showed that Rhizopus oryza produces gold nanoparticles with good monodispersity in spherical and trigonal shapes both intra- and extracellularly. Fungus Rhizopus oryza is able to produce gold nanoparticles in the size range of 10-70 nm. This biologic method has the potential to replace chemical and physical methods currently used for gold nanoparticles production

[Genetics of testicular germ cell tumors]

Testicular germ cell tumor [TGCT] is the most solid tumor in 20 - 40 years old man. TGCT account for 95% of testicular tumors and represent a unique type of human cancer from several different perspectives. TGCT arise by transformation of germ cells. The Transformed germ cells exhibit ploripotentially to differentiate into embryonic. Extra-embryonic, and somatic tissue types, and are highly sensitive to cisplatin-based chemotherapy. Investigation into the genetics of TGCT can provide methods of molecular diagnosis and help to the understanding of molecular basis of transformation, differentiation and sensitivity/resistance. The molecular basis for the chemosensitivity of these tumors is poorly understood, although initial studies suggest that wild-type p53 might play a central role, further studies will provide insights into why other solid tumors remain far from curable. The following review will provide information about genetic altration and chromosomal aberration occur in TGCT. These studies have identified multiplication of 12p, manifested in I [12p] or tandem duplication of 12p. As a unique change in TGCT which serves as a diagnostic marker. These data also indicate that multiple genetic events play a role in distinct pathways in the development of TGCT, and further elucidation of the underlying genetic and biochemical mechanisms is central to unraveling biology and improving treatment of TGCT