Subject(s)
Antineoplastic Agents/pharmacology , Cell Survival/drug effects , Fungi/chemistry , Furans/pharmacology , Antineoplastic Agents/chemistry , Antineoplastic Agents/isolation & purification , Furans/chemistry , Furans/isolation & purification , HL-60 Cells , Humans , Magnetic Resonance Spectroscopy , Mass SpectrometryABSTRACT
During our screening program for natural product drugs effective against multidrug-resistant mammalian cells, we have discovered a new delta lactone FD-211 from the fermantation broth of Myceliophthora lutea TF-0409. FD-211 had a broad spectrum activity against cultured tumor cell lines, including adriamycin-resistant HL-60 cells.
Subject(s)
Antineoplastic Agents/pharmacology , Lactones/pharmacology , Animals , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/isolation & purification , Anti-Bacterial Agents/pharmacology , Antineoplastic Agents/chemistry , Antineoplastic Agents/isolation & purification , Drug Screening Assays, Antitumor , HeLa Cells , Humans , Lactones/chemistry , Lactones/isolation & purification , Leukemia P388/drug therapy , Mice , Microscopy, Electron, Scanning , Mitosporic Fungi/metabolism , Mitosporic Fungi/ultrastructure , Spectrum Analysis , Tumor Cells, CulturedABSTRACT
Hair cells and nerve fibers inside the organ of Corti of the C57BL/6J mouse, which is known as the precocious presbycusis model, were studied using the scanning electron microscope. For this study, we used thick serial sections cut from celloidin blocks. In the 5-week-old mice, hair cell loss was not seen. The upper tunnel radial fibers crossed the upper part of the tunnel of Corti and entered the Nuel's space between the outer pillar cells. The fibers varied in diameter and showed many varicosities. The basilar fibers emerged into the tunnel of Corti beneath the upper tunnel radial fibers and crossed the floor of tunnel slightly curving basalward. The outer spiral fibers ran along the lateral wall of the Nuel's spaces, sometimes buried in the cytoplasm of Deiters' cells. The nerve endings were clearly seen on the modiolar sides of the outer hair cell bases in the basal turn. In the 30-, 42- and 60-week-old mice, hair cell degeneration was seen both at the basal and apical portions, more pronounced in the former. The outer hair cells were affected more than the inner hair cells. In the basal turn where most of outer hair cells had degenerated, the upper tunnel radial fibers disappeared while the basilar fibers remained. These results suggest that degeneration of the efferent fibers occur earlier than those of the afferent to the outer hair cells.
Subject(s)
Aging , Cochlea/innervation , Hair Cells, Auditory/ultrastructure , Organ of Corti/ultrastructure , Animals , Cochlea/ultrastructure , Disease Models, Animal , Hair Cells, Auditory/physiology , Mice , Mice, Inbred C57BL , Microscopy, Electron, Scanning , PresbycusisABSTRACT
In many cases of acoustic tumor the hearing loss is gradually progressive, but some cases of acoustic tumor show a sudden onset of hearing loss. In this paper we report two interesting cases of acoustic tumors which were diagnosed as sudden deafness at the first examination. Being treated with steroid hormones, their hearing was partially recovered. But the hearing loss recurred in both cases. At the second examination, CT showed the cerebellopontine angle tumors. So it was emphasized that careful questioning as well as the caloric test and the auditory brainstem response (ABR) was important. If one of these tests shows abnormality, the patient should be examined by the CT scan. The same may be said of patients who show recovery due to steroid hormone therapy.
