PubMed Health⌕ Search

Biomedical subjects

S Higo

Publications and source records attributed to S Higo.

At least 19 recordsLinked to original sources
PubMed2006

Different effects of high molecular weight sodium hyaluronate and NSAID on the progression of the cartilage degeneration in rabbit OA model.

OBJECTIVE: We examined the effects of nonsteroidal anti-inflammatory drug (NSAID) and intra-articular injections of sodium hyaluronate (HA) on cartilage degeneration in rabbit knee osteoarthritis (OA) model induced by partial meniscectomy. METHODS: Loxoprofen sodium (LOX) was used as the NSAID, administered p.o. once daily for 14 days at a dose of 4 mg/kg, starting from the day of meniscectomy. Suvenyl(SVE) was used as the high molecular weight HA, injected intra-articularly into injured knee every 3 days from the day of surgery. The effect on pain was assessed by an Incapacitance Tester, and the damage of cartilage was evaluated by visual assessment and histopathology at 14 days after the surgery. RESULTS: Hind paw weight bearing on the injured paw decreased time-dependently in the control group. In other three groups, the decrease of hind paw weight distribution was suppressed, demonstrating an analgesic effect. Visible damage and histopathological findings of cartilage degeneration were evident in the cartilages of the control group at day 14. In the SVE group, the damaged cartilage area decreased and cartilage degeneration was ameliorated. In contrast, in the LOX group, the cartilage degeneration was augmented compared with the control group. And, this exacerbated cartilage degeneration induced by LOX was reversed by the concomitant use of SVE. CONCLUSION: Our data show that the treatment with high molecular weight HA from earlier stage is strongly recommended to preserve the structure of cartilage.

Adjuvants, Immunologic↗
PubMed1999

Zonal organization of the ventral lateral geniculate nucleus in the cat: cholera toxin mapping.

A zonal organization of the ventral lateral geniculate nucleus (LGNv) in the cat was studied with the bidirectional tracing method by using the subunit b of cholera toxin (CTb) as the marker. The prime objectives of the present study were to examine precise distribution of terminals of the retinal afferents to the LGNv, and to correlate it with the origins and terminations of the other central connections of the nucleus. The results obtained are summarized as follows: (1) the LGNv of the cat is divided into 3 zones according to the terminations of retinal afferents: lateral, intermediate, and medial; (2) the lateral zone receives afferents from the retina in which ipsi- and contralateral fibers terminate in a complementary fashion. According to the density of labeling of retinal terminals, the lateral zone is further divided into several areas. It also receives fibers from the visual related cortex; (3) the intermediate zone, which does not receive fibers from the retina nor the visual cortex, is reciprocally connected with the midbrain, primarily with the superficial layers of the superior colliculus (SC), and gives rise to thalamic projections to the nucleus centralis lateralis bilaterally; and (4) the medial zone, from which commissural fibers arise, receives afferents bilaterally from the retina, and sends fibers to the SC bilaterally. These results suggest that the LGNv of the cat has three different zones. Functional participation of each zone has been discussed.

Animals↗
PubMed1996

Direct projections from the pedunculopontine and laterodorsal tegmental nuclei to area 17 of the visual cortex in the cat.

Direct projections from the pedunculopontine tegmental nucleus (PPT) and the laterodorsal tegmental nucleus (LDT) in the brainstem to area 17 of the visual cortex were investigated in the cat by the tract-tracing method with WGA-HRP. Neurochemical nature of neurons which were labeled retrogradely with WGA-HRP injected into area 17 was also examined immunohistochemically with antibodies against choline acetyltransferase (ChAT), tyrosine hydroxylase (TH), dopamine-beta-hydroxylase (DBH), and serotonin (5-HT). After injections of WGA-HRP into area 17, neurons in the caudal half of the PPT and the LDT were retrogradely labeled bilaterally with marked ipsilateral predominance. In the LDT, about 20% of the labeled neurons showed ChAT immunoreactivity (ChAT+); the vast majority (about 80%) of the labeled cells showed TH(+) and DBH(+). In the PPT, all retrogradely labeled cells exhibited TH(+) and DBH(+), but not ChAT(+). No retrogradely labeled cells with WGA-HRP showed 5-HT(+) in the PPT or LDT. The results indicate that the caudal part of the PPT and LDT sends projection fibers to area 17, and that PPT-neurons projecting to area 17 are noradrenergic, whereas LDT-neurons projecting to area 17 are cholinergic (20%) and noradrenergic (80%).

Adrenergic Fibers↗
PubMed1992

Differential projections to the superior collicular layers from the perihypoglossal nuclei in the cat.

The primary objective of the present study is to demonstrate the presence of a projection to the superficial layers of the superior colliculus (SC) from the perihypoglossal nuclei, specifically from the nucleus intercalatus (INT) in the cat. Iontophoretic application of WGA-HRP into the perihypoglossal complex produced orthogradely labeled terminals in the SC contralaterally forming two bands: one is in the superficial gray layer, and the other in the intermediate gray layer. The superficial band was evenly distributed in the upper portion of the superficial gray layers (layers II1-2) and the deeper band existed in the intermediate gray layer (layer IV) being arranged in a discontinuous manner. Injections of the tracer into the superficial layers of the SC yielded retrogradely labeled cells only in the rostral part of the contralateral INT; by contrast, the injection confined to the deep layers produced labeling of cells exclusively in the nucleus prepositus hypoglossi (PH). Thus, the INT and the PH each project separately to the functionally different superficial and intermediate layers of the SC, respectively. On the basis of the present anatomical findings, it is suggested that the perihypoglossal nuclei as a whole contribute not only to the oculomotor but also to the visuosensory regulatory function in the SC.

Afferent Pathways↗
PubMed1990

Anatomical interconnections of the pedunculopontine tegmental nucleus and the nucleus prepositus hypoglossi in the cat.

The Pedunculopontine tegmental nucleus (PPT) is a mesopontine structure containing predominantly cholinergic neurons, and physiological data indicate its neurons transfer eye-movement gated ponto-geniculo-occipital (PGO) waves to thalamus during the rapid eye movement phase of sleep. The present study, using anterograde and retrograde tracing of wheat germ agglutinin-conjugated horseradish peroxidase, found that the medullary nucleus Prepositus hypoglossi (PH), whose neurons are known to have eye-movement-related information, projects densely to PPT, and PPT has reciprocal projections to PH. The PH-PPT projection has some topographic organization, with rostral PH to rostral PPT and caudal PH to caudal PPT projections dominating. The PH-PPT projection may furnish the anatomical substrate for input of eye movement-related information into the rostral PGO wave system.

Animals↗
PubMed1990

[Six-month intraperitoneal toxicity study of cefpirome sulfate in rats].

A six-month intraperitoneal chronic toxicity study of cefpirome sulfate (CPR) in rats as well as a two-month recovery study were carried out at dose levels of 51.2, 128, 320 and 800 mg/kg/day. The results are as follows. 1. CPR caused no remarkable clinical signs in the general condition of the animals. 2. Body weight gain was depressed in males and females given 800 mg/kg/day. Food consumption, however, was not afected at any dose level. Water consumption increased in males and females at dose of greater than or equal to 320 mg/kg/day. 3. Except an increase in urine volume in males at 800 mg/kg/day, no abnormalities in urinary parameters were found. 4. Frequent decreases in erythrocyte count, hematocrit and hemoglobin concentration were seen in males and females of the 800 mg/kg/day group. At this dose, certain males and females also showed an increase in the reticulocyte count. 5. The serum-biochemical examinations showed a very slight or slight decrease in total cholesterol in males and females given 320 mg/kg/day or more, and increases in uric acid and inorganic phosphorus concentration in some males and females given 800 mg/kg/day. 6. Very slight or slight increases in spleen weight in males and females at a dose of greater than or equal to 320 mg/kg/day, in thyroid weight in females at a dose of greater than or equal to 320 mg/kg/day and in kidney weight in males given 320 mg/kg/day or more as well as in females at 800 mg/kg/day were measured. Further, a decrease in thymus weight was seen in females of the 800 mg/kg/day group. 7. At autopsy, very slight or slight reddish browning of the thyroid was seen in males given 320 mg/kg/day or more and in females given 800 mg/kg/day.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1989

Pulmonary clearance and toxicity of zinc oxide instilled into the rat lung.

Pulmonary toxicity of zinc oxide (ZnO) was evaluated by investigating the metabolic fate and inflammatory potency of ZnO instilled into the rat lung. Groups of three rats received single intratracheal instillations of ZnO suspension at a dose of 100 micrograms Zn/rat in the time-course experiment or received 20, 50, 100, 200, 500 and 1000 micrograms Zn/rat and were killed 2 days after treatment in the dose-response experiment. It was suggested that ZnO particles were solubilized in the bronchoalveolar milieu and cleared from the lung with a half-life of 14 h. Metallothionein (MT) was induced with a peak at 2 days. The content of MT was proportional to the dose of ZnO, but contributed little for the accumulation of Zn in the lung. A dose of 20 micrograms Zn/rat was sufficient to develop maximum responses for beta-glucuronidase activity and surfactant content in the bronchoalveolar lavage fluid. Moreover, the activity of lactate dehydrogenase and protein content in the lavage fluid increased significantly at 20 micrograms Zn/rat. These results suggest that the recommended ZnO concentration in the work-place atmosphere of 5 mg/m3 might not be adequate.

Animals↗
PubMed1989

Toxicity of cadmium oxide instilled into the rat lung. II. Inflammatory responses in broncho-alveolar lavage fluid.

Biochemical and cytological responses in the broncho-alveolar lavage fluid were investigated after instillation of cadmium oxide (CdO) or cadmium chloride (CdCl2) into the rat lung. Although biochemical responses of the lung to CdO were similar to the CdCl2-exposed lung, cytological response was more sensitive to CdO than CdCl2. Increases of lactate dehydrogenase, protein content and number of cells in the lavage fluid were proportional to the dose over the range of 0.5-10 micrograms Cd/rat. beta-Glucuronidase activity in the fluid increased with dose at low doses of Cd, but the activity did not continue to increase above 2 micrograms Cd/rat. A dose-response profile of phosphorus content in the lavage fluid, which might indicate amount of surfactant produced by Type II cells was similar to that observed for beta-glucuronidase in CdO-treated rats. Thus, tolerable level of instilled CdO for the rat lung was about 2 micrograms Cd/rat.

Animals↗
PubMed1984

Ascending projections from the nucleus of the brachium of the inferior colliculus in the cat.

Ascending projections from the nucleus of the brachium of the inferior colliculus (NBIC) in the cat were studied by the autoradiographic tracing method. Many fibers from the NBIC ascend ipsilaterally in the lateral tegmentum along the medial border of the brachium of the inferior colliculus. At midbrain levels, fibers from the NBIC end in the superior colliculus, the pretectum, the central gray and the peripeduncular tegmental region bilaterally with ipsilateral predominance. NBIC fibers to the superior colliculus are distributed densely to laminae VI and III throughout the whole rostrocaudal extent of the colliculus. In the pretectum, NBIC fibers terminate in the anterior and medial nuclei and the nucleus of the posterior commissure. NBIC fibers to the dorsal thalamus are distributed largely ipsilaterally. Many NBIC fibers end in the dorsal and medial divisions of the medial geniculate body, but few in the ventral division. The NBIC also sends fibers to the suprageniculate, limitans and lateralis posterior nuclei and the lateral portion of the posterior nuclear complex; these regions of termination of NBIC fibers constitute, as a whole, a single NBIC recipient sector. Additionally, the NBIC sends fibers to the centralis lateralis, medialis dorsalis, paraventricular and subparafascicular nuclei of the thalamus.

Afferent Pathways↗
PubMed1984

Soma size comparison of the trigeminal ganglion cells giving rise to the ascending and descending tracts: a horseradish peroxidase study in the cat.

Soma size was compared between the trigeminal ganglion cells projecting to the main sensory trigeminal nucleus (Vs) and those projecting to the nucleus caudalis (Vc) of the spinal trigeminal nucleus in the cat after injection of horseradish peroxidase (HRP) into each nucleus. The results showed that the cells projecting to the Vc (Vc cells) contained by far a greater percentage of small cells than do those projecting to the Vs (Vs cells). In the Vc case, about one-half the total number of measured labeled cells were the smallest with a diameter less than 36 microns, whereas in the Vs cases, only a small proportion of the total number of measured labeled cells were that small. In addition, the results also made it clear that the Vs cells in the ophthalmic and maxillary divisions contained a higher percentage of larger cells than those in the mandibular division.

Animals↗
PubMed1984

Topographical linkage of tecto-thalamo-anterior ectosylvian sulcal cortex in the cat: an 125I-WGA autoradiographic study.

Following injection of 125I-WGA into various parts of the caudal thalamus in the cat, the distribution of orthograde and retrograde labels in the cortex around the anterior ectosylvian sulcus (AESS) and the superior colliculus (SC) was examined autoradiographically. When 125I-WGA injections involved the medial part of nucleus lateralis posterior (Lp) of the thalamus, both orthograde and retrograde labels consistently appeared in the cortex around AESS, and retrograde labels in the SC. The topographical organization of the cortical connections with the medial part of Lp can be well correlated with that of the tecto-thalamic projections, in such a way that the dorsal portion of the medial part of Lp which receives fibers from the rostromedial part of SC is connected reciprocally with the lateral lip of AESS and the crown of the anterior sylvian gyrus; whereas, the most ventral portion of the medial part of Lp which receives tectal afferents from the caudolateral part of SC is connected with the dorsal bank and fundus of AESS. These results suggest the existence of retinotopically ordered linkage between the tecto-Lp and the Lp-AESS connections in the cat.

Afferent Pathways↗
PubMed1983

Distribution of cells of origin of the corticotrigeminal projections to the nucleus caudalis of the spinal trigeminal complex in the cat. A horseradish peroxidase (HRP) study.

The cortical distribution of cells of origin of the corticotrigeminal projections to the nucleus caudalis of the cat was examined using the method of retrograde axonal transport of horseradish peroxidase (HRP). After injections of HRP into the nucleus caudalis, labeled cells were distributed densely in the anterior suprasylvian gyrus, the coronal gyrus, and the ventral part of the anterior sigmoid gyrus, and moderately in the rostral part of the anterior ectosylvian gyrus on the contralateral side. In the anterior suprasylvian gyrus, the distribution extended rostrocaudally from the lateral ansate sulcal level to about 4.0 mm caudal to this level and mediolaterally throughout the convex of the anterior suprasylvian gyrus. All cortical labeled cells were pyramidal cells of various sizes in layer V.

Animals↗
PubMed1982

The cerebellar projections to the superior colliculus and pretectum in the cat: an autoradiographic and horseradish peroxidase study.

Efferent projections from the cerebellar nuclei to the superior colliculus and the pretectum have been studied using both retrograde and orthograde labeling techniques in the cat. In order to identify what parts of the cerebellar nuclei project to the superior colliculus and the pretectum, the retrograde horseradish labeling technique was employed. In another set of experiments, tritiated amino acids were injected into each of the cerebellar regions from which the cerebello-tectal and cerebello-pretectal projections arise, and the laminar and spatial distributions of orthograde labeling in the superior colliculus and the pretectum were compared. The results showed that the cerebello-tectal projections arise from two different regions of the cerebellar nuclei: the caudal half of the medial nucleus and the ventrolateral part of the posterior interposed nucleus. Fibers arising from the medial nucleus distribute bilaterally in the superficial zone of the intermediate gray layer in the superior colliculus, while those originating from the posterior interposed nucleus terminate contralaterally in the deeper aspect of the intermediate gray layer and in the deep gray and white layers. Although the lateral nucleus does not contribute to the cerebello-tectal projection, it projects profusely to the pretectum contralaterally. The origin of the cerebello-pretectal projection lies in the parvicellular part of the lateral nucleus. Among several pretectal nuclei, the posterior pretectal, the medial pretectal nucleus and the reticular part of the anterior pretectal nucleus receive the cerebellar afferents. The findings of the differential projections from the cerebellum to the superior colliculus and the pretectum suggest that the cerebellum exerts a regulatory influence on visuo-motor and somato-motor transfer in these midbrain structures by differential circuits.

Animals↗