Dissection of fission yeast microtubule associating protein p93Dis1: regions implicated in regulated localization and microtubule interaction

Background : Fission yeast microtubule associating protein (MAP) p93^Dis1 functions for sister chromatid separation: dis1 mutants fail to separate chromosomes, while the spindle elongates but without cyclin destruction. p93^Dis1 localizes along microtubules in interphase cytoplasm, but shifts to the spindle pole body (SPB) and spindle microtubules upon the entry into mitosis. In this study, regions of p93^Dis1 were dissected to examine their role.
Results : Nitrocellulose filter blotting shows that recombinant Dis1 binds to bovine brain microtubules in vitro . A basic central region rich in S, T and P is essential for this association. However, the whole p93^Dis1 with N- and C-termini containing a conserved repeat motif and heptad repeats, respectively, is necessary for normal microtubule association in vivo . The N-truncated region also binds to microtubules but only to the portions near the SPBs. Overproduction phenotypes indicate that p93^Dis1 greatly affects spindle formation and cell morphogenesis. The central region is essential but, by itself, not sufficient for generating such effects.
Conclusions : We propose that p93^Dis1 consists of three regions which carry distinct properties for localization: the N-region for cell cycle dependent localization, the central region for direct microtubule association, and the C-region for SPB and nuclear localization. The essential role of p93^Dis1 is carried out in the C-region, while the N-region acts as a regulator.     

Coexistence of amyotrophic lateral sclerosis and argyrophilic grain disease: A non‐demented autopsy case showing circumscribed temporal atrophy and involvement of the amygdala

We report a case of a 68‐year‐old right‐handed man with sporadic amyotrophic lateral sclerosis (ALS) and argyrophilic grain disease (AGD) having a 22‐month duration. His initial symptoms were dysarthria and swallowing difficulty at the age of 67. Subsequently bulbar palsy and pyramidal signs developed. His cognitive functions including face recognition, personality, and behavior were not changed compared with that of before the disease onset. However, magnetic resonance imaging disclosed severe right side‐predominant temporal atrophy. The neurological diagnosis was bulbar type ALS. Pathological examination disclosed histological evidence of ALS, including loss of Betz cells and lower motor neurons, corticospinal tract degeneration, and Bunina bodies. In addition, severe neuronal loss in the bilateral temporal cortex with an anterior gradient was found. Ubiquitin‐positive inclusions were encountered in the spinal anterior horn cells and hippocampal dentate gyrus, while few ubiquitin‐positive inclusions were noted in the affected temporal cortex. The amygdala, especially the basolateral nuclear group, was severely affected by neuronal loss with tissue rarefaction. Moderate neuronal loss was encountered in the parahippocampal gyrus, and to a lesser degree, in the ambient gyrus. Unexpectedly, many argyrophilic grains, coiled bodies, tau‐positive bush‐like astrocytes, pretangles, and ballooned neurons were found in the limbic system and temporal cortex. In the hippocampus, selective tau accumulation with minor neurofibrillary changes was observed in CA2 neurons. The present case suggests that (i) ALS and AGD do rarely coexist, and (ii) when ALS patients have severe temporal atrophy, not only ALS with dementia but also concurrent AGD should be considered in the differential diagnosis.     

Attenuated sympathetic tone augments nitrous oxide-induced myocardial depression during high-dose fentanyl anaesthesia in dogs

The purpose of this study was to determine whether centrally mediated sympathetic tone exerts compensatory effects on nitrous oxide-induced myocardial depression during high-dose fentanyl anaesthesia. The cardiovascular responses to 60 minutes of nitrous oxide administration after fentanyl, 100 micrograms.kg-1, were examined in 18 dogs with or without autonomic blockade induced by hexamethonium. Decreases of cardiac output and left ventricular stroke work were significantly greater in dogs with autonomic blockade (n = 9) by about 20 per cent of baseline values than in dogs without autonomic blockade (n = 9) at 30, 45, and 60 min. Similarly, left ventricular dP/dt was reduced more in dogs with autonomic blockade than in dogs without autonomic blockade, but this difference was only significant at the 60-min period. It is concluded that the sympathetic nervous system provides partial compensation for myocardial depression induced by nitrous oxide in the presence of high-dose fentanyl, suggesting that large doses of fentanyl do not ablate the centrally mediated sympathomimetic effects of nitrous oxide.     

Case of ruptured gastroduodenal arterial pseudoaneurysm with penetration to the duodenum, successfully treated with transcatheter arterial embolization]

A 77-year-old man, who underwent segmental pancreatectomy for intraductal papillary mucinous adenoma in 2001, was referred to our hospital with complaints of hematemesis and melena on January, 2004. Emergency upper gastrointestinal endoscopy showed a pulsating submucosal protrusion in the duodenal bulb, which was identified as a gastroduodenal arterial aneurysm measuring 1.5cm on abdominal CT imaging. Transcatheter arterial embolization of the aneurysm with metallic coils was successfully performed. Periodically repeated endoscopic examination has revealed the coils protruding into the duodenal lumen without any serious complication.     

Isolation, sequence and expression of a cDNA encoding the alpha-chain of the feline CD8.

We have cloned, sequenced and expressed a cDNA encoding the alpha-chain of feline CD8. This clone, named FT8-10, has an open reading frame with 720 nucleotides in length encoding a protein with 239 amino acid residues. Sequence analysis has revealed that the feline CD8 alpha-chain (CD8 alpha) shares significant homology with human (T8/Leu-2), bovine (BoCD8), rat (MRC OX8) and mouse (Lyt-2) CD8 alpha subunits. Cysteine residues as well as the tyrosine kinase p56lck binding site are well conserved. Besides, no putative N-linked glycosylation site was found. Interestingly, immunofluorescence analysis of COS-7 cells transfected with feline CD8 alpha expression plasmid driven by SR alpha promoter showed that the expressed feline CD8 alpha cross-reacted with an anti-human CD8 alpha monoclonal antibody OKT8, but did not react with an anti-feline monoclonal antibody, FT-2, which is thought to recognize the feline analogue of the human T8/Leu-2 and murine Lyt-2 molecules expressed on cytotoxic/suppressor T cells.     

Feline CD 4 molecules expressed on feline non-lymphoid cell lines are not enough for productive infection of highly lymphotropic feline immunodeficiency virus isolates

Summary To investigate whether the feline CD 4 (fCD 4) molecules are involved in infections of highly lymphotropic feline immunodeficiency virus (FIV) isolates, we expressed fCD 4 stably on Crandell feline kidney cells andFelis catus whole foetus 4 cells by transfection of a cDNA encoding the fCD 4 glycoprotein, and then infected them with TM 1 and TM 2 strains of FIV, which are unable to infect these cells productively. In spite of fCD 4 being expressed on these cells, no virus production was observed. This result indicates that fCD 4 expression alone cannot induce a productive infection of the FIV TM 1 and TM 2 strains.     

Expression of interleukin-6 receptor, leukemia inhibitory factor receptor and glycoprotein 130 in the murine cerebellum and neuropathological effect of leukemia inhibitory factor on cerebellar Purkinje cells

Expression of glycoprotein 130 and the related receptors, including interleukin-6 receptor and leukemia inhibitory factor receptor, was examined in the murine cerebellum at the protein level. Western blot analysis revealed that interleukin-6 receptor, leukemia inhibitory factor receptor and glycoprotein 130 were expressed in the murine cerebellum. Immunoreactivities for interleukin-6 receptor, leukemia inhibitory factor receptor and glycoprotein 130 were strongly localized on the cell body of Purkinje cells, indicating that both interleukin-6 and leukemia inhibitory factor could act directly on Purkinje cells in murine adult mice. The expressions of interleukin-6 receptor, leukemia inhibitory factor receptor and glycoprotein 130 were observed on the cell membranes of Purkinje cells by immunoelectron microscopy. Immunoreactivity for the interleukin-6 receptor was also detected in the cytoplasm of Purkinje cells. Injection of a murine hemopoietic cell line, FDC-P1 cells, transfected with the complementary DNA encoding the leukemia inhibitory factor led to a reduction in calbindin-positive dendrites of the Purkinje cells.

The present results suggest that the leukemia inhibitory factor affects cerebellar functions through Purkinje cells.     

Electron microscopical and immunohistochemical studies on the induction of "Qi" employing needling manipulation.

During a sparrow-pecking and twisting-needle manipulation to the acupoints BL 23, 24 and 25 for an induction of "Qi", it was found that some transparent materials were binding to the needles after removed from the volunteer's skin. Electron-microscopical analysis of the transparent materials revealed that they corresponded to the injured fascia made up of collagen fibers, elastic fibers, fibroblasts, adipocytes and mast cells. Rarely were nerve fiber-like structures observed in the materials. Immunohistochemically, calcitonin gene-related peptide-positive nerve fibers could be demonstrated in the acupoint BL 24 associated fascia. A possible functional relationship between the needle manipulation and the induction of Qi-sensation is discussed along with the acupoint tissue constitution.