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Biomedical subjects

S Wakisaka

Publications and source records attributed to S Wakisaka.

At least 127 records · Page 7Linked to original sources
PubMed1995

[A case of posterior fossa hypertrophic pachymeningitis with hydrocephalus].

A 52-year-old woman was admitted to our hospital because of nausea, headache, ataxic gait, and memory disturbance. CT scans and MRI showed a markedly enhanced lesion in the dura mater of the posterior fossa, edema in the right cerebellar hemisphere, occlusion of the transverse sinus, and hydrocephalus, suggesting hypertrophic pachymeningitis. Chronic otitis media and mastoiditis were also noted. Subjective complaints diminished after steroid administration. The patient underwent right suboccipital craniectomy and biopsy. The dura mater was markedly thickened, and the cerebellar surface was edematous. Histological examination revealed the thickened dura mater to be infiltrated by chronic inflammatory cells of forming lymphatic follicles and accompanied by Langhans giant cells. Inflammatory cells were not found in the cerebellar parenchyma, but were present in the subarachnoid space. Acid-fast stain, PAS and Grocott stain were negative. The cause of the hypertrophic pachymeningitis in this patient, may have been related to the chronic otitis media, but the patient's clinical course suggested that it might represent so-called "idiopathic hypertrophic pachymeningitis".

Cranial Fossa, Posterior↗
PubMed1994

Effects of peripheral axotomy of the inferior alveolar nerve on the levels of neuropeptide Y in rat trigeminal primary afferent neurons.

The effects of peripheral axotomy of the inferior alveolar nerve (IAN) on the presence and distribution of neuropeptide Y (NPY)-like immunoreactivity (IR) in the trigeminal sensory nuclear complex (TSNC) and trigeminal ganglion were investigated in the rat by immunohistochemistry. In the normal trigeminal ganglion, there were no NPY-IR cells, and some perivascular nerve fibres exhibited NPY-IR. In normal TSNC, many NPY-IR axons and nerve terminals were observed in the superficial layers of the subnucleus caudalis (SpVc) and paratrigeminal nucleus (paraV), but were sparse in the other subnuclei of the TSNC. Fourteen days following peripheral axotomy of the IAN, many large- and medium-sized cells in the trigeminal ganglion displayed NPY-IR, and marked increases in the numbers and staining densities of NPY-IR were observed in deeper laminae (laminae III-V) of the dorso-medial region of the SpVc and other nuclei, in addition to the dorso-medial region of the spinal trigeminal tract. Degrees of alterations of the levels of NPY were most marked in the SpVc. The present results indicate that peripheral axotomy of the IAN evokes the appearance of NPY-IR in the trigeminal ganglion and alterations of NPY-IR in the entire IAN projection areas of the TSNC.

Animals↗
PubMed1994

Effects of sympathectomy on the cutaneous temperature abnormalities in rats with chronic constriction injury of the sciatic nerve.

Effects of surgical sympathectomy on the cutaneous temperature abnormalities of plantar surface evoked by the chronic constriction injury (CCI) of the sciatic nerve were investigated in the rat. In normal animals, there were very small temperature differences between both plantar surfaces. There were also very small temperature differences in plantar surfaces following the sympathectomy prior to CCI. In rats with CCI, the cutaneous temperature of the nerve-injured plantar surface was significantly higher (warmer) than that of the contralateral plantar surface during the first week following CCI, and then became lower (cooler). Surgical sympathectomy prior to and just after CCI significant suppressed the temperature abnormalities during the first week, but no effect was observed after 2 weeks following CCI. These observations indicate that sympathetic vasoconstriction may contribute to the cutaneous temperature abnormalities evoked by CCI during the early stage, but does not affect the abnormalities at later stages.

Animals↗
PubMed1994

Induction of Fos protein in the rat trigeminal nucleus complex during an experimental tooth movement.

The induction and temporal changes of Fos protein in the rat spinal trigeminal nucleus complex during experimental tooth movement were studied immunohistochemically. Separating elastics were unilaterally inserted between the upper molars. The animals were perfused at 0, 1, 2, 4, 8, 12 and 24 h thereafter, and the brains containing the mesencephalic trigeminal nucleus and the spinal trigeminal nucleus complex were then removed. Cells showing Fos immunoreactivity were observed in the superficial layers of the subnucleus caudalis on the ipsilateral side except at 0 and 24 h. The numbers of the immunoreactive cells peaked 2 and 4 h after the insertion. On the contralateral side, only a few immunoreactive cells were observed in the subnucleus caudalis of the 1-, 2- and 4-h groups. The subnucleus interporalis and the subnucleus oralis of the spinal trigeminal nucleus complex, the principal trigeminal nucleus and the mesencephalic trigeminal nucleus of the experimental animals and all the trigeminal nuclei of the control animals contained no immunopositive cells. Thus experimental tooth movement induced a Fos protein in the superficial layers of the subnucleus caudalis of the spinal trigeminal nucleus complex. The subnucleus caudalis may modulate pain induced by tooth movement.

Animals↗
PubMed1994

NADPH-diaphorase in the spinal trigeminal nucleus oralis and rostral solitary tract nucleus of rats.

NADPH-diaphorase histochemical staining demonstrated a distinct neural group that might synthesize nitric oxide in the lower brainstem of rats. The NADPH-diaphorase stain revealed a Golgi-like network in the dorsomedial spinal trigeminal nucleus oralis and rostrolateral solitary tract nucleus, whereas this network was more dense in the latter nucleus. The distribution of NADPH-diaphorase-positive neurons in these areas overlapped with parts of central terminations from the chorda tympani nerve, as demonstrated with transganglionic transport of wheatgerm agglutinin conjugated horseradish peroxidase. The number of NADPH-diaphorase-positive neurons changed after chorda tympani nerve lesion relative to the contralateral side. The control value (%) was 106.0 +/- 4.9 (mean +/- S.E.M.). One hour after the nerve lesion, the value increased to 115.2 +/- 9.1 (P > 0.05). It then decreased to 83.9 +/- 5.2 two days after the lesion (P < 0.05), and remained at this reduced level for one or two weeks, 83.2 +/- 3.0 (P < 0.01) and 83.7 +/- 2.3 (P < 0.01), respectively. This statistically significant reduction recovered to control level 103.4 +/- 2.9 four weeks after the lesion. These results show that NADPH-diaphorase-positive neurons in the lower brainstem could be regulated trans-synaptically by primary afferents, possibly gustatory inputs.

Animals↗
PubMed1994

Development of preparing small-amount samples for transmission electron microscopy.

The means of examination of small-amount samples by transmission electron microscopy (TEM) is described. In this study, the amount of cells necessary for TEM was examined by using a KMU-100 cultured cell line. Floating cells diluted with phosphate buffer solution (PBS) to several concentrations, were gathered in the tip of Beem capsules by means of centrifuge. After fixation, dehydration, and embedding with Epon 812, the samples were cut with a diamond knife, followed by electron staining, and examined by TEM. As a result, we learned that an amount of cells over 1 x 10(3) could be observed by TEM. In spite of cell damage through this procedure, the microscopic structures of the cells were relatively maintained compared with the original cell monolayers. In the near future, it may be possible to examine the sorted cells by flow cytometry (FCM) with TEM.

Brain Neoplasms↗
PubMed1994

Cerebral blood flow study in patients with moyamoya disease evaluated by IMP SPECT.

UNLABELLED: We studied the usefulness of IMP SPECT with acetazolamide in 16 patients with moyamoya disease. Cerebral angiography was performed for all patients who were classified in three grades according to their angiographic stages. METHODS: Techniques used included ring-type emission computed tomography with a minicomputer system. Patients received 111 MBq of 123I-IMP and SPECT images were obtained 20 min postinjection. Nine patients were studied using iodoamphetamine (IMP) SPECT with and without acetazolamide. IMP SPECT with acetazolamide was performed 20 min after each injection of 1 g of acetazolamide. RESULTS: Low perfusion areas in the upper and lower frontal, parietal and temporal regions in grades 2 and 3 using IMP SPECT were observed. The mean cerebral-to-cerebellar activity ratios (C/C ratio) of six regions (upper and lower frontal, temporal, parietal occipital and basal ganglia) in grades 1, 2 and 3 were 0.96 to 1.06, 0.91 to 0.96 and 0.76 to 0.88, respectively. CONCLUSION: Our results indicate that measurement of regional cerebral blood flow (rCBF) elucidates cerebral hemodynamic factors, including the reactivity of cerebral vessels which cannot be detected angiographically in patients with moyamoya disease, and that the acetazolamide test is useful for detecting cerebral blood flow reserve. The test can be used to detect disease progress prospectively.

Acetazolamide↗
PubMed1993

c-Fos expression in the parabrachial nucleus after ingestion of sodium chloride in the rat.

The distribution of evoked expression of the proto-oncogene c-Fos was immunohistochemically examined in the parabrachial nucleus (PBN) of the rat after free ingestion of NaCl and some other taste solutions. C-Fos-like immunoreactive neurones (c-Fos neurones) were densely observed in the external lateral subnucleus (els), central lateral subnucleus (cls), and the central part of the medial subnucleus (ms). The finding that the number of c-Fos neurones decreased dramatically in the ms after treatment of the tongue with amiloride or after dissection of the chorda tympani suggests that the taste information of NaCl projects mainly to the ms. The functional significance of the els and cls is discussed, and it is suggested that the els is a recipient zone for general visceral inputs and the cls is concerned with palatability of the liquids ingested. The present study has proved that c-Fos immunoreactivity is a useful anatomical marker for activated neurones in the PBN during ingestive behaviour.

Amiloride↗
PubMed1993

Cell size-specific appearance of neuropeptide Y in the trigeminal ganglion following peripheral axotomy of different branches of the mandibular nerve of the rat.

The effect of peripheral axotomy of the mental nerve (MN) and the cutaneous branch of the mylohyoid nerve (MhN) on the appearance of neuropeptide Y-like immunoreactivity (NPY-IR) in cells in the trigeminal ganglion of the rat was examined with combined retrograde-tracing and immunohistochemistry. Retrograde-tracing with True Blue (TB) revealed that the cell-size spectrum of the trigeminal cells sending peripheral processes to the MN (TB MN cells) ranged from 75.9 to 1560.5 microns2 (or from 9.8 to 44.6 microns in diameter); approximately 53% of TB MN cells were 300-600 microns2. TB MhN cells ranged from 47.7 to 1261.5 microns2 (or from 7.8 to 40.1 microns in diameter); 56% of TB MhN cells were < 300 microns2. In the normal trigeminal ganglion, there were no NPY-IR cells. 14 days after MN transection, approximately 35% of TB MN cells displayed NPY-IR. The distribution of the cross-sectional areas of NPY-IR cells after MN transection was very similar to that of TB MN cells. Transection of MhN also induced the appearance of NPY-IR in the trigeminal ganglion but to a lesser extent (approximately 17% of TB MhN cells). The distribution of the cross-sectional areas of NPY-IR cells after MhN transection was similar to that of NPY-IR cells after MN transection. These results indicate that injury-evoked NPY-IR is specific for the medium- and large-sized ganglion cells.

Animals↗
PubMed1993

Developmental abnormalities of corticospinal tract neurons in prenatally irradiated rats: a study using retrograde labeling with Fast blue and intracellular Lucifer yellow staining.

The effect of prenatal X-irradiation on the ontogenesis of corticospinal tract (CST) neurons was examined in rats using retrograde labeling with Fast blue and intracellular Lucifer yellow staining. In prenatally irradiated rats, the cortical laminar architecture of the CST neurons was confused and many cells demonstrated migratory disturbances. Migratory-disordered CST neurons at deeper cortical levels resembled pyramidal cells, but their apical dendrites were oriented in various directions and the development of their dendrites was poor. Migratory-disordered CST neurons near the ependymal layer demonstrated round somata and many thin dendrites with spokewise radiation, suggesting a maturation disturbance. These results suggested that prenatal X-irradiation impeded the migration and maturation of CST neurons. These findings may form the basis for analyzing the mechanisms of radiation-induced mental retardation and behavioral changes.

Abnormalities, Radiation-Induced↗
PubMed1993

Changes of lectin staining pattern of the Golgi stack during differentiation of the ameloblast in developing rat molar tooth germs.

Changes of lectin staining patterns in the Golgi stack during cell differentiation were examined in the ameloblasts of developing rat molar tooth germs, using HRP-labeled lectins: Canavalia ensiformis (Con A), Griffonia simplicifolia I (GS-I), Glycine max (SBA), Ulex europeus I (UEA-I), Triticum vulgaris (WGA), and Arachis hypogaea (PNA). The Golgi stacks of the inner enamel epithelial cells and the presecretory ameloblasts were stained with the lectins, although the staining strength and pattern varied among the stacks with each lectin. In some cases, the reaction products for the lectins were observed in most or all saccules of the Golgi stack. In the secretory ameloblasts, however, discrete staining patterns of the Golgi stack were found for each lectin. The reaction products deposited in definite saccules of the Golgi stack of the secretory ameloblast, especially for UEA-I and PNA which stained only the trans Golgi saccules of the stack. The reaction-positive saccules distributed more extensively in the Golgi stack of the inner enamel epithelial cell and the presecretory ameloblast than in the secretory ameloblast. These findings suggest that the Golgi stack is not fully compartmentalized in the inner enamel epithelial cell and the presecretory ameloblast. It is proposed that, in the differentiating ameloblast, various glycosyltransferases may coexist in most saccules of the Golgi stack.

Ameloblasts↗
PubMed1993

Time sequential single photon emission computed tomography studies in brain tumour using thallium-201.

Time sequential single photon emission computed tomography (SPECT) studies using thallium-201 were performed in 25 patients with brain tumours to evaluate the kinetics of thallium in the tumour and the biological malignancy grade preoperatively. After acquisition and reconstruction of SPECT data from 1 min post injection to 48 h (1, 2, 3, 4, 5, 6, 7, 8, 9, 10 and 15-20 min, followed by 4-6, 24 and 48 h), the thallium uptake ratio in the tumour versus the homologous contralateral area of the brain was calculated and compared with findings of X-ray CT, magnetic resonance imaging, cerebral angiography and histological investigations. Early uptake of thallium in tumours was related to tumour vascularity and the disruption of the blood-brain barrier. High and rapid uptake and slow reduction of thallium indicated a hypervascular malignant tumour; however, high and rapid uptake but rapid reduction of thallium indicated a hypervascular benign tumour, such as meningioma. Hypovascular and benign tumours tended to show low uptake and slow reduction of thallium. Long-lasting retention or uptake of thallium indicates tumour malignancy.

Brain↗
PubMed1993

Appearance of neuropeptide Y-like immunoreactive cells in the rat trigeminal ganglion following dental injuries.

The effects of these injuries on the presence and distribution of neuropeptide Y (NPY)-immunoreactive (-IR) neurones were examined immunohistochemically. In the normal trigeminal ganglion: some perivascular nerves displayed NPY-IR but there were no NPY-IR ganglionic cells. Fourteen days after extraction or pulp exposure of the upper first molar, NPY-IR cells appeared in the maxillary region of the trigeminal ganglion. About 90% of the injury-evoked NPY-IR cells had medium to large diameters (more than 300 microns2 in cross-sectional area). Shallow cavity preparation, however, did not induce the appearance of NPY-IR cells in the trigeminal ganglion. These results indicate the dental injuries alter the primary sensory neurones in the trigeminal ganglion.

Animals↗
PubMed1993

Rhinocerebral mucormycosis--case report.

A rare case of rhinocerebral mucormycosis occurred in a 74-year-old diabetic male with gradually progressive right visual loss and total ophthalmoplegia. Computed tomography and magnetic resonance imaging revealed an invasive right orbital apex mass, destroying the medial wall of the orbit and extending into the right cavernous sinus and right middle fossa. Laboratory data demonstrated no signs of inflammation. A carcinomatous lesion originating in the paranasal sinuses and extending into the intracranial space was diagnosed. The mass was totally removed through a subfrontal approach to confirm the histological diagnosis and decompress the optic nerve. The histological diagnosis was mucormycosis. Despite aggressive medical therapy, dissemination resulted in mucor pleuritis and mucor encephalitis or meningitis. He died of septic shock and acute renal failure.

Aged↗
PubMed1993

Thallium-201 SPECT for predicting histological types of meningiomas.

Early and delayed 201Tl SPECT studies were performed on 13 patients with intracranial meningiomas, which were classified in three groups according to their histological types: meningothelial (n = 7); transitional and fibroblastic (n = 3); and malignant types (n = 3). The early uptake indices (UI, ratios of average counts/pixel in the lesion to those of the contralateral area on early images) were relatively high in all types: meningothelial meningiomas, 5.75 +/- 2.16 (mean +/- s.d.); transitional and fibroblastic meningiomas, 4.69 +/- 0.54; and malignant meningiomas, 7.10 +/- 3.72. There were no statistical differences in relation to histological type. The delayed uptake indices were 2.65 +/- 0.89, 3.37 +/- 1.02, and 5.16 +/- 1.62, respectively. Statistically, the delayed UI of meningothelial meningiomas were lower than those of malignant types (p < 0.05). The retention indices (RI, ratios of delayed to early UI) were 0.48 +/- 0.08, 0.79 +/- 0.16, and 0.84 +/- 0.16, respectively. The RI of the meningothelial type were also statistically lower than those of the other two groups (p < 0.05). There were no statistically significant differences between transitional plus fibroblastic types and malignant meningiomas. We conclude that 201Tl exhibits early high accumulations in all types of meningiomas, but its retention rates probably differ according to histological types, and a high retention index is predictive of the malignant potential in a meningioma.

Adult↗
PubMed1993

[A case of intracranial malignant melanoma with increased uptake of IMP in SPECT].

A patient with intracranial malignant melanoma was assessed by 123I-IMP SPECT. Early image, performed 30 minutes after intravenous injection of 111 MBq 123I-IMP, demonstrated an accumulation similar to normal gray matter-defect. Delayed image, performed 4-hour after injection, demonstrated increased accumulation of 123I-IMP. 123I-IMP SPECT, especially delayed scan, was valuable for qualitative diagnosis of intracranial malignant melanoma.

Adult↗
PubMed1992

Effects of peripheral nerve injuries and tissue inflammation on the levels of neuropeptide Y-like immunoreactivity in rat primary afferent neurons.

Changes in neuropeptide Y-like immunoreactivity (NPYir) in the rat L4 and L5 spinal cord and dorsal root ganglia (DRG) were examined after different sciatic nerve injuries (transection, loose ligation, and crush) and a localized, painful inflammation of the hind paw. Inflammation had no effect on NPYir. All the nerve injuries produced comparable increases in NPYir in ipsilateral laminae III-V axons and varicosities, and induction of NPYir in many DRG cells. Most NPYir DRG cells were medium to large (mean diameters: 40-45 microns); less than 2% of the cells had diameters of 25 microns or less. We conclude that the nerve injury-evoked increase in NPYir occurs mostly in the somata and intraspinal arbors of low-threshold mechanoreceptors; very few, if any, C-fiber afferents are involved. Nerve injury, rather than a painful condition, appears to be the stimulus for the induction of NPYir synthesis.

Animals↗