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Biomedical subjects

K Kani

Publications and source records attributed to K Kani.

At least 19 recordsLinked to original sources
PubMed1992

Immunohistochemical localization of calretinin in the rat lateral geniculate nucleus and its retino-geniculate projection.

In the present study, we examined the distribution of calretinin-immunoreactive neuronal cell bodies and fibers in the lateral geniculate nucleus of the rat. In normal rats, clusters of immunoreactive cell bodies were found in: (i) the rostral portion of the ventral lateral geniculate nucleus pars medialis (VLGM), (ii) the intergeniculate leaflet (IGL), (iii) the intermediate region between the VLGM and the ventral lateral geniculate nucleus pars lateralis (VLGL), (iv) the caudomedial portion of the VLGM, and (v) the caudolateral portion of the VLGM. In the dorsal lateral geniculate nucleus (DLG), immunoreactive cell bodies were rarely observed. After uni- or bilateral eye enucleation, no significant alteration in the morphological features or distribution of immunoreactive cell bodies was detected in the lateral geniculate nucleus. In normal rats, immunoreactive fibers formed dense plexuses in: (i) the DLG, (ii) the external layer of the VLGL, (iii) the internal layer of the VLGL, (iv) the IGL, (v) the caudomedial portion of the VLGM, and (vi) the optic tract. After unilateral eye enucleation, immunoreactive fibers in the external layer of the VLG and in the optic tract almost totally disappeared on the contralateral side to the lesion. Unilateral eye enucleation caused a significant decrease of immunoreactive fibers in the DLG and in the internal layer of the VLGL, but a substantial number of immunoreactive fibers still remained there. In the IGL and the caudomedial portion of the VLGM, no observable alteration in the distribution of immunoreactive fibers was detected after uni- or bilateral eye enucleation.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

Transient patterns of serotonergic innervation in the rat visual cortex: normal development and effects of neonatal enucleation.

The transient aggregation of serotonin (5-HT)-containing fibers in the early development of rat visual cortex was examined immunohistochemically. The aggregation of 5-HT immunoreactive (IR) fibers consisted of three stages which were classified according to the course of time and degree of space occupied. The primary aggregation appeared in the subplate and moved upward along the development of the cortex. The aggregation proceeded to the secondary stage in presumptive layer IV. The fibers extended in a column-like structure following the secondary aggregation and formed the tertiary aggregation. The upper edge of the tertiary aggregation formed a lattice-like pattern in layer I and its structure was recognized to be similar to the structure of a 'blob' which characterizes the primary visual cortex in monkey. This transient aggregation of 5-HT-IR fibers began in the subplate of the anterior visual cortex on postnatal day 2 (PND 2) and progressed towards the posterior. On PND 11, the secondary and tertiary aggregations were completed in the entire region. No further aggregation of 5-HT-IR fibers was observed on PND 15. The anterior-to-posterior axis in the aggregation process corresponds to the direction of differentiation in the layer structure of cortex. In order to investigate the relationship between the transient aggregation of 5-HT-IR fibers and the development of the visual pathway, the secondary and tertiary aggregation on PND 11 were observed after postnatal monocular or binocular enucleation. Enucleation of eye balls did not affect either the area occupied by the 5-HT-IR fibers in the secondary aggregation or the number of column structures in the tertiary aggregation. However, the contralateral and ipsilateral cortices of monocularly enucleated cases were irregularly shaped in the secondary aggregation. The distribution of 5-HT-IR fiber terminals in the binocular area (Oc1B) increased in density on the contralateral side in the monocular enucleation, while that of both sides in the binocular enucleation was of non-homogeneous density and were shaped irregularly. The above results suggest that the transient aggregation of 5-HT-IR fibers observed in the early stage of development of visual cortex is regulated primarily by the intrinsic factors, and that extrinsic factors, such as visual pathway input, affect the aggregation within the boundary of such intrinsic factors. That is, the visual pathway input and the input balance from both eyes affect the distribution density of 5-HT-IR fibers and the shape of the visual cortex, respectively.

Animals↗
PubMed1992

[Transient patterns of serotonergic innervation in the rat visual cortex--normal development and effects of enucleation].

Serotonergic innervation formed transient dense aggregation in all rat primary sensory areas during early postnatal development. In the normal rat visual cortex, there were three stages in the transient aggregation of serotonin immunoreactive fibers from postnatal day (PND) 2 to 15. Primary aggregates appeared in the subplate prior to the differentiation of layer IV, and moved upward to the lower layer of cortical plate to form secondary aggregates. Secondary aggregation gave rise to ascending fibers on the cortical surface which were roughly grouped in columns (tertiary aggregation). The serotonin fibers of the tertiary aggregates were arranged in a lattice-like pattern in layer I, and were significantly altered either in size of distribution area or column number after monocular or binocular enucleation. These data indicate that the lattice-like pattern of serotonin innervation in neonatal rats may be an evolutionary precursor of the "blobs" seen in the higher primates.

Animals↗
PubMed1991

Investigations of origins of serotonergic projection to developing rat visual cortex: a combined retrograde tracing and immunohistochemical study.

The present study investigated whether the raphe neurons which give rise to the transient serotonergic fibers in the visual cortex of neonatal rats persist or disappear as the rats mature. Three experiments were performed employing the WGA-apoHRP-Au retrograde transport technique in conjunction with 5-HT or WGA-HRP immunohistochemical staining. WGA-apoHRP-Au was injected into the primary visual cortex of all rats 9 days postnatally. In the first experiment, the animals were examined after 2 days; retrogradely labeled cells were observed in the dorsal raphe nucleus (DR), the median raphe nucleus (MR), and in the B9 and B6 cell groups; the majority (82.5%) of the cells was serotonergic. In the second experiment, the examinations took place following a survival time of 8 weeks: virtually all of the original raphe-visual cortical serotonergic neurons were found to the present. In the third experiment, also performed after 8 weeks relabeling the raphe-visual cortical neurons by WGA-HRP, it was found that 37.2% of the raphe neurons which had projected to the neonatal visual cortex no longer possessed such projections.

Aging↗
PubMed1991

Significant non-serotonergic raphe projection to the visual cortex of the rat. An immunohistochemical study combined with retrograde tracing.

The present study investigated the distribution of serotonergic and non-serotonergic raphe neurons with direct projections to the visual cortex. The study employed the WGA-apoHRP-Au retrograde transport technique combined with 5-HT immunohistochemical staining. Retrogradely labeled cells were observed in the dorsal raphe nucleus, the median raphe nucleus, and in the B9 and B6 cell groups. One notable finding was the great number of retrogradely labeled, non-5-HT immunoreactive cells. The average percentages of such cells in the various raphe regions were as follows: DR: 52% (n = 401); MR: 35% (n = 311); B9: 24% (n = 129); B6: 95% (n = 200). The present study demonstrated the presence of a significant proportion of non-serotonergic raphe region neurons projecting to the primary visual cortex in the rat. It is suggested that these neurons may complement the aminergic neurons as part of the ascending system which controls the functions of the visual cortex.

Animals↗
PubMed1991

[A double-labeling study of serotonin neurons that project to the visual cortex of developing rat brain].

Immunohistochemical studies of developing rat brains revealed aggregation of serotonin terminal fibers in the visual cortex at from 7 to 14 postnatal days. This aggregation is transient, disappearing 2 weeks after birth. The cells of origin of these serotonin terminals were investigated using double-labeling with retrogradely transported WGA-apoHRP-Au and serotonin immunohistochemistry. WGA-apoHRP-Au was injected into the rat visual cortex on the 9th day after birth. The rats were allowed to survive for 2 days and sacrificed with perfusion. Cryostat sections of the brain were processed with silver-enhancement to develop the retrogradely transported WGA-apoHRP-Au, and then serotonin immunohistochemistry was performed. Double-labeled cells that were labeled with WGA-apoHRP-Au and serotonin-immunoreactive were found mostly in the raphe medianus and raphe dorsalis in rostral and caudal sections of the mesencephalon, respectively.

Animals↗
PubMed1990

A multipurpose dye laser photocoagulation system.

We modified a single argon/dye laser photocoagulator by adding two optical fibers so that it could be used with a slit-lamp microscope, an operating microscope, and with an endophotocoagulation probe. One fiber is attached to a nearby slit-lamp microscope; the other extends approximately 70 m and can be connected to either an operating microscope or an endophotocoagulation probe. An electrically-operated mirror inside the machine controls which of the two fibers the laser beam passes through. Separate control boxes for each fiber permit direct regulation of the photocoagulation process in all situations.

Argon↗
PubMed1990

[Computed tomography of skeletal muscles in myotonic muscular dystrophy].

The computed tomography (CT) of skeletal muscles was performed on 12 patients with myotonic muscular dystrophy (MyD). We have sliced at seven levels; those are 1. neck level-at the level of thyroid cartilage 2. shoulder girdle level-at the level of upper edge of sternum 3. upper arm level-at the level of middle of upper arm 4. abdominal level-at the level of L3 vertebra 5. pelvic girdle level-at the level of middle inguinal ligament 6. thigh level-at the level of middle of thigh 7. lower leg level-at the maximum size level of lower leg. The characteristic changes of MyD are; the sternocleidomastoid muscles are most severely affected, and the paravertebral and straight abdominal muscles also tend to be severely atrophied with lower CT density. Concerning thigh levels, the deeply located muscles and muscles for extension are predominantly affected. At the lower leg levels, the calf muscles are severely affected. The muscles of levator scapulae, trapezius, psoas major, iliopsoas, gluteus, and tibialis posterior tend to be preserved. In the tight, the compensatory hypertrophy is observed often in the rectus femoris muscles and rarely in the gracilis muscles with the involvements of the agonist muscles. It might be also important to examine the changes of muscles as a whole and to know the grade of atrophy for planning the life style. The CT examination would be recommended by this standpoint.

Adult↗
PubMed1989

Dopaminergic cells in the superior cervical ganglion of the rat: light and electron microscopic study using an antibody against dopamine.

So-called small intensely fluorescent (SIF) cells were visualized immunohistochemically using a newly developed anti-dopamine (DA) serum in the rat superior cervical ganglia (SCG), both light and electron microscopically. Specificity of the anti-DA serum was tested in a control test and enzyme-linked immunosorbent assay (ELISA). DA-immunoreactivity was found in a subpopulation of SIF cells, but not in principal neurons. Ultrastructurally, DA-immunoreactivity was noticed in the cytoplasmic matrix and vesicles of perikarya, dendritic processes and terminals of SIF cells. DA-labeled terminals made symmetrical synaptic contacts with unlabeled principal neurons. These findings provide a morphological basis for the role of dopaminergic SIF cells as interneurons.

Animals↗
PubMed1988

Carnosine-like immunoreactivity in the olfactory bulb of the rat: an electron microscopic study.

Carnosine-immunoreactive primary olfactory nerve terminals are demonstrated in the glomerular layer of the rat olfactory bulb by immunoelectron microscopy. Asymmetrical synapses between dendrites of mitral/tufted cells and that of periglomerular cells could be observed. In the accessory olfactory system, carnosine-like immunoreactivity is also detected in the vomeronasal neurons.

Animals↗
PubMed1979

Eye position and electromyographic observation of squint eyes under general anesthesia.

The position of eyes under general anesthesia was measured in different groups of nonparalytic strabismus. Almost all patients with esotropia or hyperactive inferior oblique muscle showed divergent eye positions while patients with exotropia showed no consistent trend. The eye position of patients with lid ptosis without squint, which served as a control group, were divergent in all cases. Electromyographic observation of the medial rectus muscle under the same condition of anesthesia revealed that muscle discharge disappeared almost completely at the stage at which the eyes were in a well-stabilized position.

Adolescent↗
PubMed1977

Mercury in human amniotic fluid.

The levels of inorganic and organic mercury in human amniotic fluid were examined in 57 Japanese pregnant women with a gestational age of 4 months to term. Inorganic mercury was detected in all but two samples, while organic mercury was found in only 30 women. The level of inorganic mercury was higher than organic mercury. The highest levels of both inorganic and organic mercury were observed in the seventh month of gestation.

Amniotic Fluid↗