Production of Aerial Conidia of Lecanicillium lecanii 41185 by Solid-State Fermentation for Use as a Mycoinsecticide

The production of aerial conidia of Lecanicillium lecanii 41185, a highly virulent fungus, by solid-state fermentation was studied for use as a biocontrol agent against aphids. Among several agro-industrial solid media, steamed polished rice was found to produce the highest amount of aerial conidia. The optimal conditions for aerial conidia production were determined to be a 28.5% moisture content in the rice, 25degrees C culture temperature, rice pH of 6.0, 75% ambient relative humidity, 4-dold seeding culture, 0.6% KNO3, and 12 d of culture time. The conidia yield increased from 5.7 x 10(9) conidia/g polished rice to 18.2 x 10(9) conidia/g polished rice following application of these optimized conditions.

The Genetic Alterations of Retinoblastoma Gene in Human Gliomas

The formation and malignant progression of gliomas are generally considered to undergo multistepped process like other tumors. Loss of 13q is implicated in the later stage of progression of gliomas. The retinoblastoma susceptibility gene(RB gene), located at the 13q14, is a prototypic tumor suppressor gene. Many kinds of tumors are noted to have mutations of the RB gene. To determine whether the loss of 13q is associated with RB gene or not, and to find the intragenic mutation of RB, we examined 28 gliomas for loss of heterozygosity(LOH) at the RB locus using a polymerase chain reaction-based restriction fragment length polymorphism(PCR-based RFLP) assay. We found LOH in 13 of 28(46%) gliomas. Eight of 12(67%) high-grade astrocytomas, 3 of 6(50%) differentiated astrocytomas showed LOH. And we also detected LOH in 1 of 2 anaplastic oligodendrogliomas and in 1 of 7(14%) differentiated oligodendrogliomas. When we classify them into low-grade and high-grade gliomas, 4 of 14(29%) low-grade gliomas, and 9 of 14(64%) high-grade gliomas showed LOH, PCR-SSCP analysis was performed on exon, 8, 14, 15, 16, 19, 20, 21, 22, 24 to find mutations in remaining allele, and one case of mobility shift was identified in glioblastoma multiforme which showed LOH in PCR-based RFLP study. Our results demonstrate that RB deletions are detected in both low-grade high-grade gliomas, and unlike the p53 gene, genetic alterations of the RB gene in gliomas are mainly deletions rather than point mutations.

Enhanced expression of the c-myc protooncogene in human intracranial meningiomas

We examined the alteration and expression of c-myc protooncogene in 11 human intracranial meningiomas using Southern blot, Northern blot and immunohistochemical techniques. Southern blot showed neither amplification nor rearrangement but Northern blot and immunohistochemical study revealed enhanced expression of the c-myc gene. Immunohistochemically, c-myc product was found in all of the 11 cases and seven of these cases showed an above moderate degree of immunoreaction in semiquantitative analysis. Loss of heterozygosity at IGLC2 locus on chromosome 22 was detected in four of the 8 informative cases. But extent and intensity of immunoreactivity did not correlated with loss of heterozygosity on chromosome 22. These genetic changes may play important roles in the pathogenesis of human intracranial meningioma.

Overcome of acquired resistance to cisplatin by buthionine sulfoximine in human stomach and lung cancer cell lines / 대한암학회지

No abstract available.