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Biomedical subjects

K Miyoshi

Publications and source records attributed to K Miyoshi.

At least 145 records · Page 8Linked to original sources
PubMed1991

An autopsy case of mitochondrial encephalomyopathy with prominent degeneration in olivo-ponto-cerebellar system.

We describe a sporadic case of adult-onset, complex I deficiency mitochondrial encephalomyopathy (MEM), the clinical and pathological features of which failed to fit any of the known subgroups of MEM, such as Kearns-Sayre syndrome, mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes or myoclonus epilepsy with ragged-red fibers. Clinically, this patient had only progressive cerebellar ataxia, generalized muscle weakness and hearing loss. The principal finding at autopsy was degeneration of the olivo-ponto-cerebellar system. This case suggests that mitochondrial disease could underlie some cases of olivo-ponto-cerebellar atrophy.

Cerebellum↗
PubMed1991

The existence of filaments connecting the granules and the cell membrane in rat peritoneal mast cells.

SEM images of rat peritoneal mast cells showed that microtubule-like filaments seemed to penetrate the granules and project several branches just beneath the granular surface. Each granule appeared to be a cluster of microgranules. TEM observations frequently revealed microtubules connecting the granule surface to the subplasmalemmal network or to the adjacent granule surface and on some occasions, microtubules also appeared to penetrate the granule membranes. Moreover, TEM revealed that individual granules seemed to consist of a mass of microgranules, each 10-15 nm in diameter; freeze-fracture images showed similar configurations. These findings suggest that the microtubule-like filamentous structures in mast cells play a role corresponding to that of the open canalicular system in platelets.

Animals↗
PubMed1991

Nonradioactive detection of nucleic acid by the universal probe system.

A convenient and nonradioactive method for DNA hybridization tests termed the "Universal probe system" has been developed. This method is based on the principle of sandwich hybridization. This system consists of two single-stranded DNA probes (a primary probe and a biotin-labeled secondary probe). The primary probe is prepared from a chimeric phage-plasmid vector containing the complementary sequence to a target gene. The secondary probe has a sequence complementary to the vector portion of the primary probe and is labeled with biotin via the transamination reaction. An advantage of this method is that the single-stranded primary probe can be prepared with ease by using the chimeric phage-plasmid vector system, thereby avoiding tedious labeling of individually different probes. As the primary probe is not modified with biotin and other labels, it conserves the sequence to be hybridized with a target. Accordingly, the primary probe containing a relatively short hybridizing region (ca. 50 bp) can efficiently hybridize with the target. In fact, the universal probe is sensitive enough to detect a single-copy human gene on Southern blots.

Biotin↗
PubMed1991

Echocardiographic evaluation of fibrous replacement in the myocardium of patients with Duchenne muscular dystrophy.

OBJECTIVES: To study myocardial echo amplitude in Duchenne muscular dystrophy and to examine the implications of increased echo amplitude. DESIGN: Regional echo amplitude, wall motion, and uptake of thallium-201 were examined in the left ventricular wall and the relation between these variables was investigated. SETTING: Hara National Sanatorium, Japan. PATIENTS: Seven healthy controls aged 10-28 years and 14 patients with Duchenne muscular dystrophy aged 12 to 30 years. INTERVENTIONS: Echocardiography with a sector scanner (Hitachi EUB-150, Japan) and a 3.5 MHz transducer (Hitachi EUP-S21, Japan); thallium-201 myocardial single photon emission computed tomography at rest with a rotating gamma camera system (Hitachi RC-135DT, Japan). MAIN OUTCOME MEASURES: Echo amplitude of the myocardium, thickness and wall motion of the posterior wall and ventricular septum, and myocardial uptake of thallium-201. RESULTS: Areas of increased echo amplitude were detected along the outer half of or throughout the posterior wall of left ventricle in nine of the 14 patients. Their posterior walls showed significantly decreased maximal systolic and diastolic endocardial velocities (mean (SE) 31.4 (16.0) and 55.6 (53.5) mm/s) compared with normal subjects (57.7(19.4) and 113.0 (27.5) mm/s), and decreased uptake of thallium-201. Their ventricular septa, however, showed normal echo amplitude and wall motion and normal uptake of thallium-201. CONCLUSION: Areas of increased echo amplitude were detected in the posterior walls of left ventricles of patients with Duchenne muscular dystrophy. These areas were suspected to be the sites of myocardial fibrosis.

Adolescent↗
PubMed1991

[Two cases of familial idiopathic basal ganglia calcifications (BCG) with non-symptomatic family members].

We reported two families each propositus of which exhibited extrapyramidal signs and dementia with bilateral basal ganglia calcifications (BGC), while some of the other non-symptomatic family members showed BCG on brain CT by further examinations. Family 1) A 49-year-old woman was normal until her mid 40s when her memory began to fail. At age 40, dementia, finger-tremor and rigidity were observed and with brain CT and Magnetic Resonance Imaging, BCG and dentate calcifications were found. Her two daughters (20 years old and 26 years old) were free of any neuropsychiatric symptoms, but with CT examinations disclosed BCG. Family 2) A 40-year-old man. His symptoms started at 33 years old. He noticed gradually increasing finger-tremor, rigidity and dysarthria. At 40 years he showed mild dementia and BCG on Brain CT. His mother (64 years old) was non-symptomatic but CT showed that she had BCG. In the two families the calcium, phosphorous and parathyroid hormone levels, and Ellsworth-Howard test were normal. Other specific etiology including infections and somatic abnormalities was not discovered. Familial idiopathic basal ganglia calcification was considered to be rare. But the main purpose of this report is to point out that we must pay attention to the possibility of BCG of non-symptomatic family members if one showed dementia and extrapyramidal signs, and BCG on Brain CT in middle age.

Adult↗
PubMed1991

[Serum monitoring of methotrexate (MTX) and 7-hydroxymethotrexate concentrations in patients treated with MTX using high-pressure liquid chromatography (HPLC) and comparison of serum MTX levels between HPLC method and fluorescence polarization immunoassay (FPIA)].

In order to measure simultaneously the serum levels of methotrexate (MTX) and its major metabolite, 7-hydroxymethotrexate (7-OH-MTX), in samples obtained from patients treated with MTX, we have investigated the reversed-phase high-pressure liquid chromatographic assay using ion-pairing reagents. The mobile phase consisted of 77.5% solution of 0.005M tetrabutylammonium and 22.5% acetonitrile. SEP-PAK C18 Cartridges were used for the precolumn. The detectable range of MTX and 7-OH-MTX were 0.02-0.03 and 1.0 mumol/l respectively. A significant positive correlation was observed (r = 0.983) between FPIA and HPLC methods. Serum MTX levels with FPIA were significantly (p less than 0.05) higher than those of HPLC method. The serum 7-OH-MTX levels at 24 hr and 48 hr were 4.857 +/- 1.383 (n = 10) and 1.835 +/- 0.286 (n = 6) mumol/l respectively with the dosage of 400 mg/m2. The serum 7-OH-MTX levels at 48 hr were 6.254 +/- 3.053 mumol/l (n = 5) with the dosage of 3,000 mg. The serum half lives of MTX and 7-OH-MTX were 8.05 +/- 1.03 (n = 4) and 14.8 +/- 1.35 (n = 6) hours respectively between 24 hr and 48 hr after administration. The T1/2 7-OH-MTX/MTX ratio was 1.8. Percent cross-reactivity of 7-OH-MTX with concentrations ranging from 1-10 mumol/l were 0.6-2.0% by FPIA. However, patients' serum levels of 7-OH-MTX were 15-85 times (n = 21) higher than those of MTX. MTX levels of containing both MTX and 7-OH-MTX (7-OH-MTX/MTX ratio was 50/1) were significantly higher than those of containing MTX alone by FPIA.

Adult↗
PubMed1990

Cerebellar degeneration induced by acetyl-ethyl-tetramethyl-tetralin(AETT).

The neurotoxicity of acetyl-ethyl-tetramethyl-tetralin (AETT) was investigated following its percutaneous administration to rats. Animals exposed to a high-dose of AETT developed a gait abnormality that progressed to severe ataxia. Microscopic examinations revealed remarkable cerebellar changes in addition to a widespread accumulation of ceroid-like pigmentation in the neuronal cytoplasm. The cerebellar changes, especially in the vermis and intermediate part, were characterized by selective degeneration and depopulation of Purkinje cells, and a spongy state of the cerebellar white matter, which was formed in splits in the intraperiod lines within the myelin sheath. In contrast, there were only negligible changes of granule cells and other neuronal elements. Accumulation of ceroid-like pigments and selective damage to the Purkinje cells seen in the present study together provide a basis for understanding the pathogenesis of AETT intoxication and distinguish it from other experimentally induced conditions. Thus, high-dosage AETT intoxicated rats may constitute a new experimental model of cerebellar degeneration.

Animals↗
PubMed1990

Structural organization of the bovine adrenodoxin gene.

The gene structure of bovine adrenodoxin (Ad), a component of the steroid hydroxylating system in adrenal cortex mitochondria, was determined. This gene seems to be a single copy, but contains a pseudo exon in addition to the genuine gene region. The gene region for the active Ad is divided into 4 exons by 3 introns, and spans at least 27 kb. All the splice donor and acceptor sites follow the GT/AG rule. The transcription initiation site was determined by primer extension analysis, and putative TATA and GC boxes are present in the 5'-flanking region. A 12 base sequence, CCAGGGCCAGGG, is present 95 bases upstream from the transcription initiation site. A similar sequence was also found in the 5'-flanking regions of all genes for the steroid hydroxylating cytochromes P-450: P-450(SCC), P-450(11 beta), P-450(17 alpha), and P-450(C21), in the adrenal cortex. The consensus sequence for these five sequences is CGCAGGGCCATGGGA. The pseudo exon, exon 1', was present about 0.5 kb upstream from exon 1. It encodes the prepeptide region of the minor type Ad mRNA, but has a stop codon (TAA) in the frame. A TATA-box-like sequence and a CAAT-box-like sequence are also present in the 5'-flanking region of exon 1'. The GC content of exon 1 was over 80%, whereas for each of the other four exons, including exon 1', it was about 40%. Our observations suggest that exon 1, which encodes the prepeptide region of the major type Ad mRNA, has intruded into the region between exon 1' and exon 2.

Adrenodoxin↗
PubMed1990

Evidence for in vivo synthesis of thiamin triphosphate by cytosolic adenylate kinase in chicken skeletal muscle.

We showed previously that cytosolic adenylate kinase (AK1) purified from pig skeletal muscle catalyzes in vitro formation of thiamin triphosphate (TTP) from thiamin diphosphate (TDP) and ADP in addition to ATP formation from ADP [Shikata, H. et al. (1989) Biochem. Int. 18, 933-942]. To obtain evidence for in vivo synthesis of TTP by AK1, changes in TTP content and AK1 activity were determined in chicken skeletal muscle during development after hatching. Thiamin phosphate metabolism in chicken skeletal muscle was also studied. i) An extremely high TTP content, 81% of total thiamin (thiamin plus thiamin phosphates), was detected in the white (fast-twitch) muscle of adult normal chicken (5th to 9th month) compared with a relatively high TTP content of 31% in the red (slow-tonic) muscle. Since approximately equivalent amounts of total thiamin were present in the two types of muscle, the ratio of TTP to TDP was high (5.0) in the white muscle and low (0.41) in the red muscle. ii) Rabbit anti-chicken AK1 antiserum against the purified chicken cytosolic AK1 preparation was obtained. Both AK1 activity and TTP-synthesizing activity in crude cytosol fraction of adult chicken white muscle were inhibited in parallel by the antiserum. iii) In the white muscle of normal chicken, the TTP content and AK1 activity responsible for forming either ATP or TTP were increased in a parallel manner up to day 16 after hatching, after which both remained constant. In the red muscle, on the other hand, both the TTP content and the AK1 activity were low in comparison with those in the white muscle, and were almost constant after hatching.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenosine Triphosphate↗
PubMed1990

Detection of varicella-zoster virus DNA by field-inversion gel electrophoresis.

A new method for detection of varicella-zoster virus (VZV) DNA using field-inversion gel electrophoresis (FIGE) was devised. VZV-genomic DNA could be differentiated from the host cell DNA of human embryonic lung (HEL) fibroblasts infected with VZV under electrophoretic conditions allowing resolution of linear and double-stranded DNAs in the 49-230 kilobase pairs (Kb) range. The detection of VZV-genomic DNA from infected HEL cells was successful regardless of whether the VZV was a laboratory strain, live vaccine strain, or fresh isolate. Under the same electrophoretic conditions, DNA of VZV-infected HEL cells could be clearly differentiated from DNA obtained from HEL cells infected with herpes simplex virus type 1 (HSV-1), type 2 (HSV-2), or human cytomegalovirus (HCMV). Furthermore, VZV genomic DNA could be detected from as small a sample as 1.9 x 10(4) VZV-infected HEL cells. Finally, we could detect VZV genomic DNA from 10 samples of vesicle tissue (blister lids, each about 1-4 mm2) and one sample of vesicle fluid (about 5 microliters) obtained from patients diagnosed as having herpes-zoster. The results of this study indicate that FIGE is a simple and promising method for the detection of VZV from clinical materials as well as infected in vitro cultured cells.

Blotting, Southern↗
PubMed1990

Collagen degradation and mucosal mast cell in endometrium of mouse uterus during early postpartum period.

On the morning of the day of parturition, several parts in the endometrium showed edema in which collagen birefringence was not observed, indicating that collagen degradation occurs firstly in the endematous area. Undegradated collagen might be redistributed wholly in the endometrium on postpartum day 1 when the area of endometrium has diminished. The number of mucosal mast cells in the endometrium did not fluctuate in parallel with the endometrial collagen-degrading process, suggesting that mucosal mast cells do not participate in the collagen degradation during the early postpartum period.

Animals↗
PubMed1990

Synthesis and biological evaluation of quinocarcin derivatives.

Cyanation of quinocarcin readily opened the oxazolidine ring to provide DX-52-1 (2), which was a key compound in the synthesis of quinocarcin derivatives. Various electrophilic reactions toward aromatic ring of DX-52-1 were examined, and 10-substituted (e.g., halogen, nitro, formyl, cyano, hydroxy, etc.) analogs were prepared. Dehydrocyanation of the derivatives could be achieved to reproduce the oxazolidine ring upon treatment with HCl or AgNO3. 10-Chloride 10 and 10-bromide 11 were the most promising among the derivatives prepared. Antitumor activity of 10 was extended to B-16 melanoma.

Animals↗
PubMed1990

CD8+ cutaneous T-cell lymphoma with pagetoid epidermotropism and angiocentric and angiodestructive infiltration.

A 68-year-old woman had a peculiar clinical course of cutaneous lymphoma. She first developed nonpuritic erythematous macules with fine scales followed by development of erythematous infiltrated plaques. The clinical course could be interpreted as that of mycosis fungoides. Histologically, the lesions showed pagetoid infiltration of atypical lymphoid cells. Suddenly, with high fever, numerous purpuric, ulcerated, or crusted plaques with underlying infiltration or nodules began to appear on most areas of the patient's body. Biopsy specimens of the lesions revealed angiocentric and angiodestructive infiltration by neoplastic T cells and marked epidermotropism of these cells. These atypical cells immunohistochemically had CD8+ surface phenotype. The patient died of respiratory insufficiency due to acute pulmonary infiltration. Autopsy demonstrated angiocentric and angiodestructive lymphomatous infiltration in the lung.

Aged↗
PubMed1990

[A new method of preparation of doxorubicin-in-oil suspension using ultrasonificator attached with Cuphorn].

The property of selective deposition of oily contrast medium, Lipiodol (LPD), in tumor tissue was utilized for targetting intraarterial infusion chemotherapy for hepatic cancers. For this therapy anti-cancer agents need to be suspended in LPD. In this report the new suspension device using ultrasonificator attached with Cuphorn was studied. Doxorubicin (Dx) was stable to ultrasonification for 1 hour. Ten mg/ml of Dx was mixed with LPD and this mixture was treated 2 times for 5 minutes with the ultrasonification method. This procedure was simple and sterile, as the commercially used Dx vials into which LPD was injected were set in the Cuphorn and ultrasonificated just as sealed. Microscopic examination of the suspension showed uniform dispersion of Dx particles without formation of aggregates. Dx particles were finely and regularly fragmented. In vitro the suspensions showed a gradual release of Dx from LPD to water phase. In one case with hepatocellular carcinoma received intraarterial infusion of this suspension, the size of the tumor and serum level of alpha-fetoprotein was prominently decreased. This ultrasonification method was simple and convenient to prepare Dx-in-oil suspension.

Carcinoma, Hepatocellular↗