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Biomedical subjects

Y Morikawa

Publications and source records attributed to Y Morikawa.

At least 289 records · Page 16Linked to original sources
PubMed1984

Morphology and function of human neuroblastoma xenotransplanted in nude mice.

Nine human neuroblastomas were serially transplanted in nude mice. All transplanted tumors were taken from patients older than the age of 1 year 10 months. In contrast, the authors were unable to transplant tumors from patients younger than 1 year 7 months of age, in spite of many attempts. All transplanted tumors produced varying amounts of cathecolamines as revealed by the liquid chromatography and formalin-induced fluorescence techniques. The content of the cathecolamines was closely correlated with the number and size of secretory granules. In high cathecolamine-producing tumors, cell clusters showing strong yellow-orange fluorescence plus a positive argyrophil reaction suggesting pheochromoblastic differentiation were demonstrated by our combined cathecolamine fluorescence and argyrophil reaction method. One of the transplantable tumor lines was demonstrated by unique host responses and biochemical data, to produce adrenocorticotropic hormone and increased cathecolamines. Our observations indicate that neuroblastoma derived from neural crest cells seem to have a nearly complete hormone production function as compared with their normal counterparts.

Adrenal Gland Neoplasms↗
PubMed1984

Developmental changes in the effects of lidocaine on the electrophysiological properties of canine Purkinje fibers.

Developmental changes in the cardiac effects of antiarrhythmic drugs have been noted in the clinical setting. To study whether these might in part be based on developmental differences in drug effects on the transmembrane potential, we used standard microelectrode techniques to study the effects of lidocaine on the transmembrane potentials of Purkinje fibers from adult and young dogs. Control studies of membrane responsiveness and steady state recovery kinetics of Vmax showed no age-related differences in these variables. Lidocaine reduced Vmax of adult fibers to a greater extent than that of young fibers at basic drive cycle lengths of 1000 and 400 msec. The number of beats to reach steady state Vmax at basic drive cycle length of 400 msec was smaller in adult than in young fibers. Both tonic and use-dependent block appeared to be greater and to develop more rapidly in the adult than the young fibers. Moreover, fibers from young dogs recovered more rapidly from the effects of lidocaine than did adult fibers. These data suggest there are developmental changes in the tonic and use-dependent effects of lidocaine that may contribute to age-related differences in drug effect.

Action Potentials↗
PubMed1984

Immunoperoxidase demonstration of a new muscle protein (Z-protein) in myogenic tumors as a diagnostic aid.

Z-protein, a new muscle protein with a molecular weight of 55,000 daltons recently discovered in Japan, is an excellent marker for muscle differentiation in paraffin sections. Positive staining by a peroxidase-antiperoxidase technique for detection of intracellular Z-protein was observed in 2 of 2 cardiac rhabdomyomas, 5 of 5 leiomyomas, 9 of 10 leiomyosarcomas, and in 15 of 18 rhabdomyosarcomas including 5 of 5 of the pleomorphic type, 7 of 9 of the embryonal type, and 3 of 4 of the alveolar type. Other types of tumors (77 cases) that sometimes mimic myogenic tumors on histologic examination gave negative results. The immunoperoxidase method for detection of intracellular Z-protein is of use in distinguishing myogenic tumors from other types of tumors.

Adolescent↗
PubMed1984

A clinicopathological study of histiocytosis X.

Thirty-five cases of histiocytosis X in the National Children's Hospital were clinicopathologically studied. Fourteen cases were categorized in diffuse histiocytosis X, Letterer-Siwe type (DHX), 19 cases in multifocal eosinophilic granuloma (MEG) and 2 cases in unifocal eosinophilic granuloma (UEG). Nine of 14 DHX died, of which 6 died of opportunistic infection due to hypoproteinemia and pancytopenia, and 3 died of pulmonary fibrosis probably due to histiocytic infiltration and resultant lymphedema. Infiltration of histiocytes in the bone marrow, thymus and lungs, in addition to the lymphoreticular organs, was conspicuous in autopsy cases of DHX. Skin biopsy was valuable for diagnosis and the immunostaining with anti-S100 antibody was a good marker to characterize infiltrating histiocytes. Prognostic factors and effects of treatments were also evaluated. Only one of 19 MEG died of opportunistic viral infection, but a longer duration for treatment was usually necessary compared to that for DHX. Pathogenesis of histiocytosis X was discussed in relation to T-zone histiocytes.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1983

Extended dissection of the portahepatis and creation of an intussuscepted ileocolic conduit for biliary atresia.

This paper introduces a new operation for biliary atresia that establishes successful biliary drainage by extending the portahepatic dissection, and decreases ascending cholangitis by incorporating a nonrefluxing intussuscepted draining conduit. An analysis of the postoperative results is presented. The usual dissection of the portahepatis is extended to include the area between and beneath the branches of the right portal vein to incorporate all potentially usable remnants of the intrahepatic ducts. Ascending cholangitis is decreased by interposing an intussuscepted ileocolic segment between the portahepatis and the abdominal wall. This extended dissection of the portahepatis was performed since 1978 in 15 infants with noncorrectable biliary atresia, and bile drainage was achieved in all. In ten infants an intussuscepted ileocolic conduit was constructed. Ascending cholangitis in these ten infants has been either completely absent or easily controlled by antibiotics. The draining bile was highly concentrated due to the water-absorbing capacity of the interposed colonic segment; therefore, fluid and electrolyte disturbances, which develop frequently in patients having jejunal conduits, have never been encountered.

Bile↗
PubMed1983

Development of responses by facial expressions and eye movements in neonates and young infants.

Eye movements and facial expressions were assessed in 177 normal neonates and infants under 150 days of age after the examiner gazed into their eyes for 20 seconds. Blinking to a threatening stimulus and turning of the eyes towards a red object near the examiner's face were tested. The eye movements abruptly changed from fine nystagmoid movements to distinct rolling movements suggesting observation of the examiner's face after 70-80 days of age. Rapid turning of the eyes towards the red object also appeared from the same age, while blinking developed gradually after 40 days of age. Most infants under 80-90 days of age knitted their brows and showed esophoria in response to the examiner's face or facial movements, but such responses gradually disappeared after 90 days of age when social smiles developed. Eye movements and facial expressions during early infancy are very informative in developmental evaluations.

Blinking↗
PubMed1983

Characterization of canine distemper viruses adapted to neural cells and their neurovirulence in mice.

Interaction of the Onderstepoort strain of canine distemper virus (CDV) with three established human neural cells, i.e. IMR-32 neuroblastoma, 118-MGC glioma and KG-1 oligodendroglioma, was examined, and adaptation of CDV to these cells was also attempted. The unadapted virus was found to grow at relatively low titers in the three neural cells inducing moderate to minimal cytopathic effects (CPE). The virus was successfully grown at high titers in these cells after 8 to 10 passages. Biological characteristics such as growth rate, morphology of CPE and plaque size changed after adaptation. Analysis by SDS-polyacrylamide gel electrophoresis, however, failed to show any difference in the molecular weight of component proteins among the unadapted and three adapted viruses. Inbred DDD strain of mice developed clinical signs after intracerebral inoculation with the unadapted virus but most of them survived with histological lesions of encephalitis. Neuroblastoma-adapted virus induced only transient clinical signs in some animals with mild encephalitic lesions in the gray matter. Increases in neurovirulence were found for viruses adapted to glioma and oligodendroglioma cells. Almost all mice inoculated with these two viruses at 3 weeks of age died within 8 days with histological lesions consisting of hyperemia, edema, severe degeneration of nerve cells and a few giant cells. Demyelinating lesions in the absence of inflammatory changes were observed in the cerebellum, pons and medulla oblongata of animals inoculated with oligodendroglioma-adapted virus.

Animals↗
PubMed1981

Reappraisal of endorectal pull-through procedure. II. Animal experiment.

Anorectal manometry and pelvic histology following endorectal pull-through and simple abdominoperineal pull-through procedures were studied experimentally in dogs. dogs that had undergone endorectal pull-through preserved normal resting pressure of the anal canal, rectoanal reflex response, and intact perirectal anatomy. Dogs that had simple abdominoperineal pull-through, on the other hand, showed low anal canal pressure, loss of rectoanal reflex, and damage of the pelvic muscles. good continence following endorectal pull-through operation was supported by these physiologic and anatomic studies.

Anal Canal↗
PubMed1981

Role of alpha-adrenergic receptors in denervation supersensitivity of rat vas deferens.

Contractile responses of rat vas deferens were studied with particular attention directed to the role of receptors and neuronal control. Marked contraction of the vas deferens was observed with alpha-adrenergic agonists, depending on their concentrations. This tissue had a low sensitivity to ACh. Four days after denervation, this tissue showed a supersensitivity to alpha-adrenergic agonists and a high K+ concentration, but not to ACh. The increase in sensitivity to alpha-agonists resulted in an enhancement of the maximal response and a shift of the concentration response curve to lower concentrations of these reagents. Alterations were seen in the alpha-adrenergic receptors in the rat vas deferens, assayed by measuring the binding of [3H]WB4101. The maximal binding sites decreased significantly to 86 from 142 fmoles per mg protein. The affinity of the receptors for alpha-agonist, determined by measuring the ability of agonists to displace bound [3H] WB4101, increased significantly, while the affinity to alpha-antagonists remained unchanged. Studies on [3H]QNB binding indicated no significant change in muscarinic ACh receptors after denervation. Thus, supersensitivity of the alpha-adrenergic mechanism mediated by a specific change in affinity of alpha-receptors occurs after denervation of rat vas deferens. These changes in sensitivity and in receptors are discussed in relation to the characteristics and roles of alpha-receptors in the rat vas deferens.

Acetylcholine↗
PubMed1981

Stroop phenomena in the Japanese language: the case of ideographic characters (kanji) and syllabic characters (kana).

Utilizing a unique feature of the Japanese languages--that besides two syllabic orthographies, which have identical pronunciations, words with the same pronunciation may also be written in an orthography composed of ideographic characters--we have conducted an investigation of Stroop phenomena. The fact that pronunciations of the three Japanese orthographies are identical means that, if there are any differences between them in the Stroop phenomena observed, we can place the locus of this interference effect in the perceptual process. Five color names were written in the ideographic characters (kanji) and the two syllabic orthographies (hiragana and katakana). Color-congruent cards and incongruent cards were utilized in a color-naming task and a word-reading task. Mean required times for the color-naming condition and the word-reading conditions were compared with those for control conditions. Stroop phenomena were observed in both ideographic and syllabic orthographies. Significant differences in mean required times were observed between the ideographic and syllabic orthographies but not between the two syllabic orthographies. Interferences in comparisons of Japanese orthographies and color patch control conditions were much smaller than in the case of Stroop's (1935) experiment. A "Reverse Stroop Phenomenon" was observed only in the case of kanji on incongruent cards in the word-reading condition. The results support the hypothesis that both ideographic characters (in this case, kanji) and colors are processed in a parallel fashion in the non-dominant right cerebral hemisphere, while syllabic or phonetic characters are processed in the dominant left cerebral hemisphere.

Color Perception↗
PubMed1981

[Transfer of cefotaxime to the pelvic organs (author's transl)].

The new antibiotic cefotaxime (HR 756, CTX) has been proved to be clinically effective against infections observed in the field of obstetrics and gynecology. The present study was intended to investigate the transfer of CTX to the internal genital organs and the dead pelvic space. The results were obtained as follows: 1. The concentrations of CTX transferred to the uteri and its appendages after CTX 1 g intravenous injection were sufficiently effective against the major pathogens (Gram-negative and anaerobic bacteria) demonstrated in the field of obstetrics and gynecology. 2. The concentrations of CTX transferred to the dead space of the pelvis were effective against almost all of the Gram-negative bacteria for 6 to 12 hours after CTX 1 g or 2 g intravenous injection. CTX was thus proved to be very effective for the prevention and treatment of infections of the dead pelvic space.

Cefotaxime↗