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Biomedical subjects

K Tashiro

Publications and source records attributed to K Tashiro.

At least 505 records · Page 28Linked to original sources

Structural analysis of ribosomal DNA homologues in nucleolus-less mutant of Xenopus laevis.

Sequences homologous to the ribosomal DNA (rDNA) in a Xenopus anucleolate (nucleolus-less) mutant were analyzed by Southern blot analysis. The mutant was found to possess a variety of sequences homologous to non-transcribed spacer (NTS) and/or coding region of rDNA. 65 rDNA-homologous clones were isolated from a genomic DNA library of the mutant. All the clones showed only partial homology to the normal rDNA unit and their restriction maps differed from that of the normal rDNA unit. Based on the hybridization patterns, the rDNA-homologous clones were divided into four groups (I-IV). Structure of group IV, which most strongly hybridized to normal rDNA probe, was analyzed by nucleotide sequencing. The group IV sequence was found to contain a part of the rDNA, including Bam island, enhancer element, promoter region, external transcribed spacer, and a portion of 18S rRNA gene. The blotting analysis suggested that the group IV sequence is specific for a particular strain of Xenopus.

Animals↗

Changes in sensorimotor function associated with the degree of bradykinesia of Parkinson's disease.

Changes in coordinated eye and hand movements associated with the progress of bradykinesia were studied in 31 parkinsonian patients and 8 age-matched healthy subjects. Among the parameters expressing the changes in motor behaviour, the interval between the onset of eye and hand movements was most sensitive. This parameter reflected the difference in the progress of the symptom in the two motor systems. An increase in the reaction time of the hand response appeared in patients of grade II bradykinesia; this was observed for eye movements only in patients with grade III (severe) bradykinesia. While the changes in ocular reaction time remained within the physiological range, a lengthening of the reaction time, a reduction in peak velocity, a decrease in the open-loop gain, a prolongation of movement duration, and a slow build-up in EMG activity, appeared from an early stage in hand movement. These signs of motor disturbance may appear eventually in every motor system at an advanced stage, but their development is not synchronous in different motor systems. An analysis of the responses recorded simultaneously from the two motor systems examined made it possible to evaluate the changes in the sensorimotor processes with different grades of bradykinesia. A comparison between reaction times for eye and hand movements may be useful for assessing the degree of bradykinesia in parkinsonian patients.

Adult↗

Purification and characterization of two components of acid alpha-glucosidase from pig liver.

Acid alpha-glucosidase [EC 3.2.1.3] was purified from pig liver by a procedure including Sephadex G-100 affinity chromatography. Electrophoresis on SDS-polyacrylamide gel of the purified enzyme indicated the presence of two components with molecular weights of 73K and 64K. The two components of the enzyme were completely separated, in reasonable yield, by chromatography on a DEAE-5PW column. Both components catalyzed the hydrolysis of the alpha-1,4 and alpha-1,6 linkages of glycogen, maltose, isomaltose, dextrin, and a synthetic glucoside at acid pH. The pH optima of both components were 4.3 for maltase and glucoamylase, and 4.8 for isomaltase and dextrinase. But as to the activity on 4MU-alpha-Glc, the pH optimum of the larger component was 4.8 and that of the smaller component 5.3. The Km values of both components for 4MU-alpha-Glc, maltose, glycogen, isomaltose, and dextrin were 1.0 X 10(-4) M, 9.1 X 10(-3) M, 16.7 mg/ml, 6.7 X 10(-2) M, and 12.5 mg/ml, respectively. Erythritol, Tris, and turanose inhibited the two components competitively. The Ki values of the larger component were 5.0 X 10(-2) M, 13.3 X 10(-3) M, and 3.2 X 10(-3) M, and those of the smaller component were 2.5 X 10(-2) M, 6.1 X 10(-3) M, and 4.7 X 10(-3) M, for erythritol, Tris, and turanose, respectively.

Amino Acids↗

Immunohistochemical localization of ornithine aminotransferase in normal rat tissues by Fab'-horseradish peroxidase conjugates.

Immunohistochemical localization of ornithine aminotransferase (L-ornithine: 2-oxo-acid aminotransferase, EC 2.6.1.13), a mitochondrial enzyme whose hereditary absence induces gyrate atrophy of the choroid and retina, was elucidated by a direct immunoperoxidase method using Fab'-horseradish peroxidase conjugates. In immunodiffusion studies, the antibodies raised with the re-crystallized enzyme were highly specific to ornithine aminotransferase. To show localization of ornithine aminotransferase in normal rat tissues, clear immunohistochemical staining of this enzyme through the inner mitochondrial membrane in paraffin sections was achieved with Fab'-horseradish peroxidase conjugates. Strong immunoreactivity was present in cerebral neurons, hepatocytes, and epithelial cells of renal tubuli, gut mucous membranes, and ocular tissues. Specific distribution of ornithine aminotransferase was found in ependymal cell groups: namely, epithelial cells of the choroid plexus, pigmented and nonpigmented epithelial cells of the ciliary body. and Müller cells and pigment epithelium of the retina.

Animals↗

Multisystem degeneration: drugs and square wave jerks.

We studied a 55-year-old woman with macrosquare wave jerks and macrosaccadic oscillations with a vertical component. The oscillations almost completely disappeared after administration of diazepam, clonazepam, thiamylal, or phenobarbital. A disorder of GABAergic tonic inhibitory system from the substantia nigra to superior colliculus probably plays an important the pathogenesis of these abnormal ocular movements. role in the pathogenesis of these abnormal ocular movements.

Clonazepam↗

Preservation of Xenopus laevis rDNA-containing plasmid, pXlr101A, injected into the fertilized egg of Xenopus laevis.

A circular rDNA-containing recombinant plasmid, pXlr101A, and its vector pBR322 were microinjected into the cytoplasm of fertilized Xenopus laevis eggs. The DNAs extracted from injected embryos at various stages of development were analyzed by hybridization with 32P-labeled pBR322 as the probe. Neither pXlr101A nor pBR322 were replicated, but they were maintained until the tailbud stage, disappearing during the muscular response stage. When pXlr101A-injected embryos were raised until the 2-week-old tadpole stage, sequences homologous to pBR322 were detectable in two Eco RI fragments of the pXlr101A-injected tadpole DNA. The sizes of the Eco RI fragments suggested that the plasmid sequences were preserved most probably in the chromosome-integrated form.

Animals↗

[Estimation of 99mTc-dimercaptosuccinic acid renal uptake using single photon emission computed tomography].

Renal function was assessed by measurement of 99mTc-dimercaptosuccinic acid (DMSA) uptake by the kidney based on the transsectional tomographic image obtained by single photon emission computed tomography (SPECT). The renal uptake was expressed as percentage of the total radioactivity detected in the kidney, the volume of which was measured by convolution method, against the amount dosed. Absorption was corrected by GE-STAR method using cut off level of 42%. In order to determine normal range, measurement was made for 40 kidneys of each of 10 male and female volunteers confirmed of having normal kidneys both morphologically and functionally. The average volume of the kidney was 220.4 ml for the right and 239.3 ml for the left for males, and 205.9 ml and 236.5 ml, respectively for females. The renal uptake of radioactivity (at 2 h after injection), was 26.8% for the right and 27.6% for the left for males, with corresponding figures for females being 26.4% and 27.9%, respectively. Distribution range of renal volume and renal uptake was obtained by bivariate analysis with 90% and 95% probability. From these results, our method of renal function determination based on renal uptake of 99mTc-DMSA obtained from renal transactional tomogram by SPECT is considered to be accurate and potentially useful for clinical purpose.

Adult↗

Demonstration of herpes simplex 1 virus antigen mouse brain after fixation.

The effects of several fixatives and fixation periods on recovery of viral antigen by indirect immunofluorescence (IF) and indirect immunoperoxidase (IP) were examined in mouse brains infected with type-1 herpes simplex virus. In 10% formalin, the sensitivity of antigen detection by IF decreased after one month fixation and viral antigen was barely detectable after fixation for three months. But in 10% buffered formalin antigenicity was not lost after six months. Similar effects were obtained by IP; however, specimens fixed in 10% formalin for three and six months showed positive reactions. Viral antigen was detectable without enzyme digestion in paraffin materials fixed in Bouin's, Carnoy's and Dubosq-Brazil solutions, but when treated with proteolytic enzyme for three hours, antigen could not be detected by either IF or IP. Ten per cent buffered formalin, Bouin's or Dubosq-Brazil solutions are recommended as fixatives for retrospective immunohistochemical and histopathological studies of viral infection in autopsy and biopsy materials.

Animals↗

[Histopathological studies of the osteophytes and ossification of the posterior longitudinal ligament (OPLL) in the cervical spine].

To obtain information on ossification around the vertebral body of the cervical spine, we carried out histopathological investigation on 30 autopsy cases. The results were as follows; Intervertebral discs were untouched, anterior osteophytes developed along the anterior longitudinal ligament and they corresponded to anterior spur in spondylosis deformans. Posterior osteophytes around the posterior edges of vertebral body resulted in intervertebral insufficiency, and corresponded to hypertrophic spur in osteochondrosis. Histopathological findings of hyperostotic anterior osteophytes were similar to anterior osteophytes, but in the former there were advanced osteophyte formations. In OPLL of the segmental type, intervertebral discs were degenerated, and ossified mass did not involve the posterior longitudinal ligament of the parts of discs. With regard to morphological appearance and the tendency of increasing ossification, OPLL of the continuous type was similar to hyperostotic anterior osteophytes, without involvement of intervertebral disc. OPLL of the distinctly continuous type was differentiated from that of the segmental type.

Adult↗

[Cooperative phase II study of epirubicin (EPI) in bladder cancer, renal pelvic and ureteral tumors--Urological Cooperative Study Group of EPI].

A phase II study of a new anthracycline anti-cancer antibiotics, epirubicin (EPI), was undertaken in 71 patients with urothelial malignancies; 40 with advanced urothelial malignancies and 31 with superficial bladder cancer. Out of them 32 patients with advanced stage of urothelial cancer were evaluated for the systemic use of EPI, while 30 patients with superficial bladder cancer for intravesical use. Intravenous administration of this new anticancer antibiotic, at a dosage of 60 mg/m2 every three weeks, showed the response rate of 20.0% for advanced bladder cancer and 14.3% for renal pelvic and ureteral tumors. In cases of superficial bladder cancer, at a dosage of 60 mg/30 ml X 3 day every week in principal, the response rate was 66.7%. Eight out of 30 patients showed complete disappearance of the tumor. Twelve patients also showed more than 50% tumor regression. As for adverse effects no serious cardiotoxicity was demonstrated. Anorexia and other gastrointestinal side effects, such as nausea and vomiting, were also seen. Alopecia and myelosuppression were the major adverse effects among patients with systemic EPI administration. With intravesical use of EPI, cystitis syndrome was the major toxicity. However, no systemic side effects were noted in these cases. In conclusion, EPI was assumed to be effective for the treatment of advanced urothelial tumors and superficial bladder cancer.

Aged↗

[The coexistence of basal epidermoid tumor and trigeminal neurinoma within the posterior fossa].

Recently we encountered one case with basal epidermoid tumor originated in the cerebellopontine angle, associated with a trigeminal neurinoma of the Gasserian ganglion and trigeminal root within both middle and posterior fossa. We wish to present the case with an analytical review of the reported cases of multiple intracranial tumors. The patient was a 49-year-old man who noted the onset of left facial nerve palsy in March, 1974, which lasted for several years. In April 1976, he developed unsteadiness of gait which was not worsening. He noted left facial pain and paresthesias of tongue in October, 1981 and was pointed out as having left hearing disturbance by a physician. He was admitted to our hospital on December 11, 1981. Neurological examination showed hypalgesia and hypesthesia on his left face, left VII cranial nerve palsy and left-sided hearing loss. The IX and X cranial nerves were also involved with absent gag reflexes on the left side and swallowing difficulty. Tongue was deviated to the right on protrusion. He had mild ataxia of the left limbs, ataxic gait and horizontal gaze nystagmus to the right. He had neither café-au-lait spot nor subcutaneous tumor suggestive of von Recklinghausen's disease. CT scan revealed water density lesion in the prepontine and cerebellopontine cisterns which seemed to distort brainstem posteriorly. Metrizamide CT cisternography showed a large fungated mass filling the basal cistern. These findings strongly suggested the presence of an epidermoid tumor. A left suboccipital craniectomy was performed on May 13, 1982. A large pearly mass filling the basal cistern was removed.(ABSTRACT TRUNCATED AT 250 WORDS)

Cerebellar Neoplasms↗