Search PubMed⌕ Search

Biomedical subjects

K Niimi

Publications and source records attributed to K Niimi.

At least 73 records · Page 4Linked to original sources
PubMed1985

The organization of thalamic neurons projecting to the premotor cortex and the caudate nucleus in the cat studied by a fluorescent retrograde double labeling technique.

Thalamic neurons projecting to both the head of the caudate nucleus and the premotor cortex in the cat were studied by the retrograde fluorescent double labeling technique. After injections of Evans blue into the caudate nucleus, and diamidino-phenylindol into the premotor cortex, a small number of double labeled neurons appeared in the ventral anterior, ventral lateral, anteromedial, rhomboid, central dorsal, central lateral, central medial, paracentral and parafascicular nuclei, in addition to numerous single-labeled neurons. This indicates that some neurons in the thalamic nuclei send bifurcating axons to both the head of the caudate nucleus and the premotor cortex. The caudatal projections of these thalamic neurons are organized in a topical manner.

Animals↗
PubMed1985

Physico-chemical properties and stability of cilostazol.

The physico-chemical properties of cilostazol (6-[4-(1-cyclohexyl-1H-tetrazol-5-yl)butoxy]-3,4-dihydro-2(1H)-qui nolinone, OPC-13013), a new potential antithrombotic and vasodilating drug, were studied by clarifying its elemental composition, melting point, spectra (UV, IR, NMR and mass), X-ray diffraction pattern, thermal properties, solubilities and partition coefficient. Analytical test methods such as HPLC and TLC were established for use in stability tests, and the stability study of cilostazol in an aqueous solution (acid and base) and in a solid form was carried out. Cilostazol was shown to be stable with no changes from the initial values.

Azoles↗
PubMed1985

Thalamic projections to the posterior suprasylvian gyrus and the ventrally adjacent cortex in the cat traced with horseradish peroxidase.

The present study has been undertaken to elucidate the thalamic projections to the posterior suprasylvian gyrus (PSG) and the ventrally adjacent areas in the cat using retrograde axonal transport of horseradish peroxidase. The posterior part of the PSG, area 19 b, receives fibers mainly from the dorsolateral part of the medial pulvinar nucleus, and a lesser number from the lateral pulvinar nucleus. It receives a few fibers from the inferior pulvinar nucleus and the medial interlaminar nucleus (NIM) of the lateral geniculate. The anterior part of the PSG, area 21 b, receives a large number of fibers from the medial pulvinar nucleus, particularly its dorsolateral part, and less numerous fibers from the inferior pulvinar and lateral pulvinar nuclei. It receives only a few fibers from the lateral geniculate (NIM), suprageniculate and intralaminar nuclei, and in some cases from the ventral anterior and ventral lateral nuclei. Area 20 has thalamic connections similar to area 21 b, but it receives more fibers from the ventrolateral part of the medial pulvinar nucleus, nucleus, and receives less numerous fibers from the inferior pulvinar nucleus. It receives a few fibers from laminae C1-C2 and NIM of the lateral geniculate nucleus. Area 36 receives many fibers from the ventrolateral part of the medial pulvinar nucleus and the suprageniculate nucleus, a lesser number from the other parts of the medial pulvinar nucleus, and some fibers from the medial geniculate nucleus, particularly its dorsal principal part.

Afferent Pathways↗
PubMed1984

Projections of the medial geniculate nucleus to layer 1 of the auditory cortex in the cat traced with horseradish peroxidase.

Thalamic afferents to layer 1 of the auditory cortex in the cat have been studied using retrograde axonal transport of horseradish peroxidase. The magnocellular part of the medial geniculate nucleus sends fibers to layer 1 of the primary and secondary auditory areas and of the dorsal division of the posterior ectosylvian area. The dorsal principal part and the ventromedial portion of the ventral principal part send only a few fibers to layer 1 of these cortical areas.

Animals↗
PubMed1984

[2 cases of solitary metastasis to the large intestine from gastric carcinoma].

Localized metastatic foci of the colon from gastric cancer have been reported in only a few cases. Tow cases of gastric cancer were reported. One relapsed in the form of a localized lesion at the sigmoid colon (Case 1) and the other at the rectum and the transverse colon (Case 2) after curative resection of gastric cancer. From the results of clinical examinations obtained from these cases, it may be reasonable to postulate that peritoneal dissemination and/or lymphatic invasion of cancer was the main cause of solitary metastasis to the large intestine.

Adenocarcinoma↗
PubMed1984

Physico-chemical properties and stabilities of a new positive inotropic agent, 3,4-dihydro-6-[4-(3,4-dimethoxybenzoyl)-1-piperazinyl] -2(1H)-quinolinone (OPC-8212).

3,4-Dihydro-6-[4-(3,4- dimethoxybenzoyl )-1-piperazinyl]-2(1H)- qu inolinone ( OPC -8212), a new positive inotropic agent, was examined to clarify its physico-chemical properties, i.e. elemental analysis, melting point, spectra (UV, IR, NMR, MS), X-ray diffraction pattern, thermal analysis, solubilities, pKa, partition coefficient and chromatography (HPLC, TLC). Some degradation products of OPC -8212 were identified in acidic and basis solutions. OPC -8212 was determined by nonaqueous titration.

Cardiotonic Agents↗
PubMed1983

The laminar arrangement of limbic thalamocortical neurons in the lateropulvinar nuclei of the cat thalamus.

The topical organization of limbic cortical projections of the lateropulvinar nuclei of the thalamus in the cat was studied with the horseradish peroxidase (HRP) technique. The dorsal margins of the dorsal lateral, medial pulvinar and lateral pulvinar nuclei project to the postsubicular and presubicular areas (presubiculum in a wide sense), the most dorsal parts of these nuclei projecting to the retrosplenial area, and the dorsal parts to the cingular area. These three zones of limbic thalamocortical neurons in the lateropulvinar nuclei are arranged in lamination from the surface inward, and may be called presubicular, retrosplenial and cingular zones.

Animals↗
PubMed1983

Trinitrophenylation of spinach ferredoxin and its effect on the functions.

Spinach ferredoxin was trinitrophenylated by reaction with 2,4,6-trinitrobenzenesulfonate. Four amino groups in the ferredoxin could be modified of the total of five amino groups. The trinitrophenylated ferredoxin formed a complex with ferredoxin-NADP+ reductase just as native ferredoxin did. The modified ferredoxin also retained the activity of electron transport in the cytochrome c photoreduction system of chloroplasts, but could neither donate electrons to ferredoxin-NADP+ reductase in the NADP+ photoreduction system, nor accept electrons from the reductase in the NADPH-cytochrome c reduction system in vitro. Furthermore, it lost the inhibitory effect against the NADPH-diaphorase activity of the reductase. These results suggest that the complex formation of ferredoxin with ferredoxin-NADP+ reductase is a phenomenon essentially independent of the function of electron transport between the two proteins.

Chloroplasts↗
PubMed1983

Thalamic afferents to the anterior and middle suprasylvian gyri in the cat traced with horseradish peroxidase.

The anatomical organization of thalamic projections to the anterior and middle suprasylvian gyri in the cat has been studied by retrograde axonal transport of horseradish peroxidase. Area 5 receives a large number of fibers from the posterior lateral nucleus, and a few fibers from the dorsal lateral nucleus. It receives many fibers from the ventrolateral part of the medial pulvinar nucleus and from the suprageniculate and lateral pulvinar nuclei. Area 5 receives a considerable number of fibers from the lateral central, anterior ventral and lateral ventral nuclei, and only a few fibers from the paracentral nucleus. Area 7 receives numerous fibers from the medial pulvinar (dorsolateral and ventrolateral parts), lateral pulvinar, dorsal lateral, posterior lateral, lateral central and anterior ventral nuclei, and a lesser number from the lateral ventral nucleus. The suprageniculate and paracentral nuclei project only a few fibers to area 7. Area 21 has its main input from the medial pulvinar nucleus, mainly its dorsolateral part. It receives many fibers from the lateral pulvinar nucleus, and a few fibers from the dorsal lateral nuclei, the dorsolateral part of the posterior lateral nucleus and the lateral central and paracentral nucleus. Area 21 receives very few fibers from the dorsal lateral geniculate nucleus (NIM) and the inferior pulvinar nucleus, but receives no fibers from the anterior and lateral ventral nuclei. The thalamic afferents from the lateral bank of the lateral sulcus are similar to those from area 7 (crown). However, the lateral bank receives more fibers from the posterior lateral nucleus, and lesser fibers from the paracentral, anterior ventral and lateral ventral nuclei. It receives scarcely any fibers from the suprageniculate nucleus. The medial bank of the middle suprasylvian sulcus (Clare-Bishop area) receives cortical afferents mainly from the inferior pulvinar nucleus. It also receives fibers from the medial pulvinar nucleus, and a lesser number from the lateral pulvinar and posterior lateral nuclei. It receives a few fibers from the dorsal lateral geniculate nucleus, particularly NIM and lamina B, and very few fibers from the suprageniculate, lateral central and paracentral nuclei.

Afferent Pathways↗
PubMed1981

Thalamic afferents to the visual cortex in the cat studied by retrograde axonal transport of horseradish peroxidase.

Thalamic projections to visual areas 17, 18 and 19, neighboring suprasylvian cortex have been studied using the HRP method. Area 17 receives fibers mostly from the main laminae of the dorsal lateral geniculate nucleus (GLd). Area 18 receives inputs mainly from the central and medial interlaminar nuclei (NIC, NIM), and partly from laminae of GLd. Area 19 receives fibers principally from lamina B (C1-C2) and NIM of GLd. In addition, areas 17, 18 and 19 receive a few fibers from extrageniculate thalamic nuclei, particularly the pulvinar and intralaminar nuclei.

Afferent Pathways↗
PubMed1981

Thalamic afferents to the prefrontal cortex in the cat traced with horseradish peroxidase.

Thalamic afferents to the prefrontal cortex in the cat were traced with horseradish peroxidase (HRP). Following injections of HPR into the medial prefrontal cortex and the ventral portion of the lateral prefrontal cortex, a large number of labeled cells were found in the dorsomedial nucleus of the ipsilateral thalamus, particularly its medial and dorsal parts. Labeled cells were also detected in the submedial and ventral medial nuclei, more in the former. Very few cells were labeled in the medial part of the medial pulvinar nucleus and in the paratenial and medial central nuclei. Occasional labeled cells were seen in the paracentral, rhomboid and reuniens nuclei. Injections of HRP into the dorsal part of the lateral prefrontal cortex, including the medial bank of the presylvian sulcus, resulted in heavy labeling of cells particularly in the lateral and ventral parts of the ipsilateral dorsomedial nucleus. Some labeled cells were found in the ventral medial nucleus, and a lesser number in the submedial nucleus. Very few cells were labeled in the paratenial nucleus and in the medial part of the medial pulvinar nucleus. Occasional labeled cells were detected in the paracentral, lateral central and reuniens nuclei. The above results reveal that with regard to the thalamic afferents, appreciable differences between the dorsolateral and ventromedial prefrontal cortices were noted.

Afferent Pathways↗
PubMed1980

Ascending projections of the inferior colliculus in the cat: an autoradiographic study.

The ascending projections of the inferior colliculus (IC) in the cat were traced by the autoradiographic method, with special reference in the differenial projections of each subnucleus of IC. The laminated ventrolateral part of the central nucleus of IC (CNv) projects to the ventral and medial divisions of the ipsilateral medial geniculate body (MGB). The projections to the ventral division are topographically organized in the mediolateral direction, the terminals being arranged in the form of lamina, while those to the medial division are diffuse. The unlaminated dorsomedial part of the central nucleus of IC (CNd) sends fibers to every division of the ipsilateral MGB, particularly to the dorsal division and the ventromedial portion of the ventral division. It is noteworthy that the external nucleus of IC (EN) projects to the superior colliculus, part of the pretectum, and the anterior extremity of MGB ipsilaterally, in addition to the ventral and medial divisions of MGB. The posterior cap of IC, regarded as the pericentral nucleus of IC (PC), projects ipsilaterally to the ventral part of the caudal tip of MGB and the posterior part of the suprapeduncular nucleus. In addition of these projections, the parabrachial region and interstitial nucleus of the brachium of IC (BIC) are identified as common targets of projections of each nucleus of IC on the ipsilateral side. Contralaterally, every subnucleus of IC except for PC projects via the commissure of IC to areas corresponding to the targets of the ipsilateral projections, such as the ventral and medial divisions of MGB and the parabrachial region and the interstitial nucleus of BIC, although these contraleral projections are in general much sparser than those ipsilateral. Intrinsic and commissural connections within IC are also revealed in this study, providing characteristic configurations of each subnucleus of IC. It is concluded that the ascending projections of IC in the cat are highly differentially organized according to its subnucleus.

Animals↗
PubMed1980

Changes in cyclic nucleotide levels and dimorphic transition in Candida albicans.

The relationship between the levels of cyclic nucleotides and dimorphic transition in Candida albicans was examined. The results showed that cells of this pathogenic fungus contained both cyclic adenosine 3',5'-monophosphate (cAMP) and cyclic guanosine 3',5'-monophosphate (cGMP), the concentration of the latter being about one-tenth that of the former in stationary-phase cells of the yeast form. Our results further indicated that germ tube formation induced by incubation at 40 degrees C followed a rise in cAMP concentration in the cell with no accompanying change in cGMP content. Cysteine, which suppressed germination, also reversed the increase in intracellular cAMP concentration. Dibutyryl cAMP (1 MM) significantly promoted germination in proline medium at temperatures of 32 to 34 degrees C. These results suggested that cAMP was one of the controlling factors in the morphological transition in Candida albicans.

Bucladesine↗