Biomedical subjects

N Fujishiro

Publications and source records attributed to N Fujishiro.

31 records · Page 2Linked to original sources

PubMed1992

Systemic lupus erythematosus with sensorineural hearing loss and improvement after plasmapheresis using the double filtration method.

A 32-year-old female was diagnosed as having systemic lupus erythematosus based on her laboratory tests. In 1985 she began to complain of hearing difficulty. Her hearing ability deteriorated to the extent that her audiogram revealed a hearing loss of 90 db to 110 db in both ears in September 1989. She received two series of plasmapheresis treatments using the double filtration method. After two series of plasmapheresis treatments, her hearing improved dramatically. This improvement suggests that circulating immune complexes and anti-phospholipid antibodies might play a pathological role in the hearing impairment in SLE patient.

Adult↗

PubMed1990

Isolation and characterization of feeding behavior mutants in Drosophila melanogaster.

Feeding behavior mutants of the fruit fly Drosophila melanogaster having point-mutations were isolated. The defects were analyzed in order to study the mechanism of feeding behavior. Point-mutations named febB (three allele) and febA (three allele) were located between the X-chromosome markers cho and cv and between the markers cv and v, respectively. The febB mutants showed a higher acceptance threshold of the proboscis extension reflex than wild-type flies and showed a normal chemosensory response to the electrophysiological test. The mutant (febB2) showed a higher starvation tolerance than the wild-type fly, but this was not a cause of the high acceptance threshold. Mosaic analysis was applied to the mutant. Internal tissues were suspected to be the primary focus of the abnormal behavior.

Animals↗

PubMed1990

Effects of sodium depletion on the caffeine-induced contraction of frog's skeletal muscle.

Effects of depletion of Na ions from the environmental medium on the caffeine-induced contraction were investigated in both intact and skinned fibers prepared from the frog's fast twitch muscle. In intact muscle fibers, both the twitch and the contracture induced by 5 mM caffeine were enhanced by depleting the external Na at 9-10 degrees C. In contrast, in the mechanically skinned muscle fiber, which was used to examine the capability of the sarcoplasmic reticulum to take up Ca ions from the sarcoplasm and/or the superfusing medium, the contractile tension as well as its fractional area measured by applying 25 mM caffeine were markedly inhibited by Na-depletion at 5 degrees C. The apparent discrepancy between these two conditions is discussed.

Animals↗

PubMed1989

Twitch potentiation of frog (Rana japonica) skeletal muscle by antipyrine.

1. The effects of antipyrine on single muscle fibres from the frog Rana japonica were examined. Antipyrine potentiated the twitch tension, but did not affect the tetanus response or induce any contracture by itself. 2. The duration of the action potential was prolonged in a dose-dependent manner. 3. Antipyrine did not affect the mechanical threshold, the uptake of Ca2+, or the Ca2+ induced release of Ca2+ from the sarcoplasmic reticulum. 4. Ca2+-channel blockers did not affect the twitch potentiation by antipyrine.

Action Potentials↗

PubMed1989

[A case of chronic neutrophilic leukemia with abnormal karyotype].

A 75-year-old man was admitted to our hospital because of leukocytosis and thrombocytosis. The peripheral blood showed RBC 403 x 10(4)/microliters, Hb 14.1 g/dl, PLT 91 x 10(4)/microliters, and WBC 48,000/microliters with a differential count of 24% band forms, 65% segmented forms and 11% others. The bone marrow aspiration revealed myeloid hyperplasia (94.4% myeloid series, 4.8% erythroid series and 0.8% others), and NAP score was consistently high. The serum level of lysozyme and vitamin B12 were elevated. There were no signs of infection or other malignancy. Cytogenetic study of bone marrow cells showed mosaic karyotypes of 46,XY/46,XY,t(7;16) (q22;q24). The Ph1 chromosome was not found. A diagnosis of chronic neutrophilic leukemia was made. Serial chromosomal analysis showed the coexistence of a clone with 46,XY,t(7;16) (q22;q24) and that with 46, XY.

Aged↗

PubMed1988

Effects of external sodium removal on the contracture of frog skeletal muscle.

Effects of removal of the external sodium on the contractility of the frog's skeletal muscle were studied. Sodium-free solution, replaced by choline, strongly augmented the twitch tension before it abolished the action potential. A similar marked potentiation was also observed in the sustained contracture induced by a small depolarization under the current-clamped condition where generation of conductive action potential was blocked. On the other hand, the maximum contracture induced either by electrical stimulation or by high potassium solution was not modified by lowering the external sodium concentration. Furthermore, contraction threshold measured on the electrically induced contracture was shifted to more negative value of the membrane potential. Caffeine contracture, examined by a short-term application of 5 mM caffeine, was first inhibited by sodium-free solution but afterwards restored or even augmented during the sodium-free perfusion. From these observations it is concluded that a removal of external sodium lowered the mechanical threshold of the muscle by affecting some step of the coupling process at the T-SR junction without affecting the contractile machinery.

Animals↗

PubMed1985