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Biomedical subjects

M Yamane

Publications and source records attributed to M Yamane.

At least 109 records · Page 6Linked to original sources
PubMed1989

[A case of spinocerebellar degeneration with bilateral MLF syndrome and dystonia].

The patient, a 31-year-old married woman, noticed spasticity on walking at the age of 19 accompanied by ataxia, dysarthria and dysphagia. Facial twitching and dystonic movement of extremities have been observed since age 27. A sister of her father showed the similar ataxia and dysarthria, and expired of pneumonia at the age of 45. On admission at the age of 29, neurological examinations revealed nystagmus, marked spasticity with pathological reflexes and clonus, cerebellar ataxia, dysarthria and dysphagia, diffuse muscle wasting, fasciculation in facial musculature, and generalized slow dystonic movement. By neuro-otological studies bilateral MLF syndrome with upward gaze limitation and decreased velocity of saccadic eye movement were detected. Surface EMG at rest showed a dystonic discharges on the extremities. Needle EMG disclosed a systemic neurogenic change with reduced interference and high amplitude potentials. Atrophy of the brainstem was remarkable on the cranial CT and MRI. These abnormal eye movements, especially bilateral MLF syndrome and generalized dystonia seem to be quite unusual in the variety of spinocerebellar degenerations. On reviewing detected clinical descriptions on Joseph disease this case can be probably included.

Adult↗
PubMed1988

A DNA-binding factor specific for xenobiotic responsive elements of P-450c gene exists as a cryptic form in cytoplasm: its possible translocation to nucleus.

Transcription of the drug-metabolizing cytochrome P-450c gene is induced by 3-methylcholanthrene or 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Previously, we defined two xenobiotic responsive elements (XREs) of approximately equal to 15 base pairs, both of which activate transcription in cis in response to these xenobiotics. Using a gel mobility shift assay, we have identified a factor that specifically binds to the XREs. This factor appears in nuclei of mouse hepatoma cell line Hepa-1 only when the cells are treated with the xenobiotics, while the factor is undetectable in the nuclei of a 3-methylcholanthrene-treated mutant of Hepa-1 with defective function of a xenobiotic receptor. In addition, the nuclear factor bound to the XRE in the gel was found to be associated with [3H]TCDD when the cells were treated with it, suggesting that the xenobiotic receptor is at least a component of the DNA-binding factor. The cytoplasmic fraction from nontreated Hepa-1 cells also contains the factor as a cryptic form and prominently reveals its DNA-binding activity by incubation with 3-methylcholanthrene in vitro. These results not only suggest the involvement of the XRE-binding factor in transcriptional activation via XREs but also provide evidence that the binding of ligands to the preexisting factor in a cryptic form induces its XRE-binding activity, which is probably followed by its translocation from cytoplasm to nucleus.

Base Sequence↗
PubMed1987

Characterization of xenobiotic responsive elements upstream from the drug-metabolizing cytochrome P-450c gene: a similarity to glucocorticoid regulatory elements.

The DNA element governing the inducible expression of drug-metabolizing P-450c gene by xenobiotic treatments was investigated by gene transfer methods. A variety of dissected fragments from -844 to -1140bp region which was essential for the inducibility of P-450c gene were placed on the heterologous SV40 promoter for testing the inducibility. Mapping studies in combination with gel retardation assay defined the presence of the two xenobiotic responsive elements (XRE, XRE1, -1007 - -1021bp; XRE2, -1088 - -1092bp) composed of about 15 nucleotides which expressed the enhancer activity in response to xenobiotic inducers. The two XREs share 10 nucleotides in common out of 15 as expressed in the sequence CG/CTG/CC/TTG/CTCACGCT/AA and are arranged in the inverse orientation. They are different from DREs (drug responsive element) proposed previously (Sogawa, K. et al. Proc. Natl. Acad. Sci. 83, 8044-8048 (1986] and expressed a strong enhancer activity in response to 3-methylcholanthrene. The XRE shows a significant homology with glucocorticoid regulatory elements and apparently needs normal functions of a putative xenobiotic receptor for the inducible enhancer activity.

Animals↗
PubMed1987

The experience of otolaryngological practice on neurological patients.

This paper summarizes the experiences of three years of otolaryngological practice at the Tokyo Metropolitan Neurological Hospital. Almost 30% of the patients treated were bedridden, necessitating otolaryngologists' ward visits. Neuro-otological examinations, other otolaryngological examinations and surgical treatments were accomplished. Neurology, neurosurgery and pediatric neurology have different purposes with regard to otolaryngological consultations. This study indicates that those varied demands are a problem in conducting effective otolaryngological practice. The study concluded that otolaryngologists could play a more important role in the diagnosis and treatment of patients with diseases of the central nervous system.

Female↗
PubMed1987

Serous otitis media in amyotrophic lateral sclerosis.

Serous otitis media (SOM) is a common disease, the cause of which is not always clear. In this paper authors report the high incidence of SOM among the patients with amyotrophic lateral sclerosis (ALS). Furthermore, a comparative study about ALS and other diseases shows higher incidence of SOM in ALS. Our study indicates that SOM in ALS seems to be mainly due to muscular disturbance of eustachian tube caused by ALS, although the influence of long term supine position and nasopharyngeal irritation by nasogastric feeding tube cannot be denied in the development of SOM.

Amyotrophic Lateral Sclerosis↗
PubMed1987

Mechanism for erosion of glass-ionomer cements in an acidic buffer solution.

In order to clarify the mechanism for erosion of glass-ionomer cements, we immersed two commercial luting cements in an acidic buffer solution under various conditions. The amounts of F, Al, Si, and Ca eluted from the cement were (1) in proportion to the square root of immersion time, (2) unrelated to shape or volume of the sample, (3) dependent on its surface area, and (4) not affected by shaking of the solution. It was concluded that the dissolution was controlled by the diffusion of those species in the cement matrix, which was influenced by the structure of the matrix and the concentration of H+ ion at the cement surface. The unreacted glass particles near the cement surface were dissolved by the long immersion, and many pores were left in the surface region.

Acids↗
PubMed1986

Structural analysis of cloned cDNA for mRNA of microsomal cytochrome P-450(C21) which catalyzes steroid 21-hydroxylation in bovine adrenal cortex.

We have isolated cDNA clones of the mRNA for cytochrome P-450 that catalyzes the steroid C-21 hydroxylation (P-450(C21)), which specifically catalyzes 21-hydroxylation of steroids in the microsomes of bovine adrenal cortex by using synthetic oligonucleotides as probes. Sequence determination of the cloned cDNA showed that it contains 2157 nucleotides and a poly(A) chain and that a single open reading frame of 1488 nucleotides codes for a polypeptide of 496 amino acids with a molecular weight of 56,113. The deduced amino acid composition is in agreement with that determined by direct amino acid analysis of purified P-450(C21) and the predicted primary structure contained amino acid sequences of N-terminal region and two internal tryptic fragments of the protein so far analyzed. Comparing the amino acid sequence with those of other forms of P-450 reveals that a conserved amino acid sequence containing a putative heme-binding cysteine is present in the equivalent position, proximate to the COOH terminus of the molecules and that P-450(C21) is phylogenically situated in an intermediate position between steroidogenic mitochondrial cytochrome P-450 which catalyzes the side-chain cleavage of cholesterol (P-450(SCC)) and drug-metabolizing microsomal P-450s. However, the amino acid sequence of P-450(C21) is much closer to that of drug-metabolizing P-450s than to that of P-450(SCC).

Adrenal Cortex↗
PubMed1986

Breast cancer in a man treated effectively with a large dose of tamoxifen citrate.

Breast cancer in males is comparatively rare. A 41-year-old man visited our hospital with a complaint of left breast tumor. Initial examination showed remarkably diffuse metastatic lesions in the lung field and small metastatic lesions in the surrounding skin. Modified radical mastectomy, including the surrounding metastatic skin lesions, and incisional biopsy of the lung were performed. Estrogen receptor was positive in both the primary breast cancer and metastatic cancer lesions in the lung. Postoperative medication of tamoxifen citrate, an estrogen receptor blocking agent, in a dose of 30 mg/day, was given together with fluorouracil, BCG, cyclophosphamide, and methotrexate. No evident change could be seen in the lung field six months after the operation. The metastatic lesions in the lung disappeared two years after the operation when the dose of tamoxifen citrate was increased to 60 mg/day. At this writing, thirty months after the operation, the patient is in good health.

Adenocarcinoma↗
PubMed1986

Personal computer-controlled microsurgery of fertilized eggs and early embryos.

The microsurgery of mouse and rat eggs and early embryos was attempted using a micromanipulator driven by three pulse motors. The pulse signals that regulate the three pulse motors for the X, Y, and Z axes were controlled according to the personal computer programs produced on the basis of the displayed data. As a result, the following was found. 1) The computer-controlled operation was possible in the X and Y plane on a specimen previously suctioned and retained by a holding pipet. A microinjection pipet was inserted into the male pronucleus of a fertilized egg and the morula was bisected using a microblade; these microtools were moved horizontally. 2) A more complicated micromanipulation in two dimensions (X and Z axes), which is very difficult manually, was possible by using this system. 3) microsurgery (microinjection of a fluorescent material (FITC) into the male pronucleus, enucleation of a fertilized egg, and vertical or horizontal bisection of morulae) was carried out successfully by a student who had no practical experience in this field. These facts suggest that the system markedly facilitates microsurgery, without need for full training in the manual procedures.

Journal Article↗
PubMed1986

Location of regulatory elements responsible for drug induction in the rat cytochrome P-450c gene.

The synthesis of cytochrome P-450c is induced remarkably in cultured cells as well as animal tissues in response to added chemicals such as 3-methylcholanthrene and 2,3,7,8-tetrachlorodibenzodioxin. To study this mechanism, we joined the sequence of 5'-flanking and upstream regions of the P-450c gene to the structural gene for chloramphenicol acetyltransferase. The fusion gene was introduced into Hepa-1 cells for the assay of the expressed acetyltransferase activity. At least three cis-acting regulatory regions that are responsible for the inductive expression were determined in the sequences from nucleotide -3674 to -3067, from -1682 to -1429, and from -1139 to -1029, relative to the transcription start site, by external deletion analysis. Further detailed analysis of the region (nucleotides -1139 to -1029) most influential on the inducibility revealed that a regulatory element consisting of 10 base pairs termed a drug regulatory element (DRE) and its homologues were tandemly arranged in this region. The consensus sequence deduced from DREs is 5'-GCNTGAGGCTGGG-3'. The regulatory sequence from nucleotide -1140 to -844 is capable of conferring inducibility on a heterologous promoter in a manner independent of its orientation and distance from the subordinate promoter.

Acetyltransferases↗
PubMed1986

Complete nucleotide sequence of two steroid 21-hydroxylase genes tandemly arranged in human chromosome: a pseudogene and a genuine gene.

Two 21-hydroxylase [P-450(C21)] genes have been isolated from a human genomic library using a bovine P-450(C21) cDNA. The insert DNAs containing the P-450(C21) genes were also hybridized with the sequences of the 5' or 3' end regions of human C4 cDNA, indicating a close linkage of the P-450(C21) gene to the C4 gene. Sequence analysis has revealed that the two P-450(C21) genes are both approximately equal to 3.4 kilobases long and split into 10 exons. Comparing the two sequences, we found that the two genes are highly homologous including their introns and flanking sequences, but that three mutations render one of the two P-450(C21) genes nonfunctional--1 base insertion, an 8-base deletion, and a transition mutation--all of which may cause premature termination of the translation. Tandem arrangement of the highly homologous pseudo- and genuine genes in close proximity could account for the high incidence of P-450(C21) gene deficiency by homologous gene recombination.

Base Sequence↗