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S Wakai

Publications and source records attributed to S Wakai.

At least 145 records · Page 8Linked to original sources
PubMed1989

[On the origin of intracranial teratomas].

To investigate the origin of intracranial teratomas, the author reviewed 245 reported cases of intracranial teratoma in neonates (onset of symptoms within 2 months after birth) including his own case and compared them with those occurring in childhood registered in Brain Tumor Registry in Japan (onset of symptoms more than 2 months after birth) in terms of incidence, age distribution, locations and histological pictures. An operated case of teratoma with digit formation and well organized tissue arrangement, a presumed transitional form between teratoma and fetus-in-fetu , is presented in detail and was compared with cases of typical neonatal teratoma and a case of intracranial fetus-in-fetu documented in the literature as well. The following results were obtained: 1) There are two peaks in age distribution as to the incidence of intracranial teratomas, in the neonatal period and in childhood (10 years of age), respectively. 2) Teratomas in neonates mostly arise in the frontal lobe and/or frontal base and the lateral ventricle comprising about 29% of all cases whereas those occurring in childhood arise mostly in the pineal region (56%). 3) No germinomatous components are seen in neonatal teratomas though they are frequently observed in childhood teratomas. 4) There are some cases showing transition between teratoma and fetus-in-fetu , which is believed to originate from included twins. The results suggest that there are two pathogenetically different forms of intracranial teratomas: the one in the neonate originates from included twins and the other, which occurs in childhood originates from germ cells.

Adolescent↗
PubMed1989

[Lobar intracerebral hemorrhage secondary to cerebral amyloid angiopathy: a clinicopathologic study of three operated cases].

Three operated cases of lobar intracerebral hemorrhage (LICH) related to cerebral amyloid angiopathy (CAA) were studied clinicopathologically. They constituted about 8% of all LICH cases (n = 37) operated upon in our institute (DUSM) during the past 3 years. Case 1, 2 and 3 aged 71, 67 and 73 years, respectively. There were 2 males (Cases 1 & 2) and 1 female (Case 3). Only one case (Case 3) had both hypertension and dementia before hemorrhage. In all 3 cases, neurologic symptoms deteriorated after admission. The hematoma involved the right temporo-parietal in 1 (Case 1), the right parieto-occipital in 1 (Case 2) and the left fronto-parietal region in 1 (Case 3). Case 1 developed a new hematoma in the right occipital lobe on the day following surgery. On CT, the hematoma was multilobular in shape and located very superficially extending to the subarachnoid space in all cases. There was no abnormal enhancement in and around the hematoma upon contrast infusion. Angiography showed only an avascular mass sign in case. At surgery, the hematoma was extruded onto the cortical surface in all cases. The surgical outcome was good in 2 (Cases 1 & 2) and fair in 1 (Case 3). Removed hematomas, solid nodular tissues and adjacent brain tissues were examined histologically using hematoxylin and eosin, Azan-Mallory, elastica van Gieson, silver and Congo red stains. Arteries in the hematoma wall, the subarachnoid space and the adjacent brain parenchyma were intensely stained with Congo red and showed birefringence on polarized light.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1988

"Nidus sparing sign" on computerized tomography in intracerebral haemorrhage due to a rupture of arteriovenous malformation.

The authors investigated the validity of noncontrast computerized tomography (NCCT) to predict the presence of arteriovenous malformations (AVM) as a cause of intracerebral haemorrhage (ICH) in the acute stage. They found a small iso- or slightly hyperdense nodular or tubular defect devoid of haematoma in its periphery on NCCT in 8 of the 13 AVM cases that underwent both NCCT and contrast CT. This CT finding was named "nidus sparing sign" (NSS). This haematoma-free notch was enhanced on contrast infusion and confirmed to correspond to the AVM nidus surgically and pathologically. In one case with negative angiograms, a small AVM was verified histologically within the tissue corresponding to the NSS. The NSS noted on the NCCT could be of great value in case emergency surgery is needed for comatose patients with ICH, particularly lobar ICH, without enough time left to undergo angiography and/or magnetic resonance imaging. Neurosurgeons are able to safely perform an evacuation of the haematoma keeping in mind the possibility of a ruptured AVM and if so, the spatial relationship between the AVM nidus and the haematoma. This might also be a valuable CT sign in deciding whether or not angiography should be undertaken in ICH cases.

Adult↗
PubMed1988

Electron microscopic study of the biopsied cardiac muscle in Duchenne muscular dystrophy.

Cardiac muscular biopsies were performed on 4 patients with Duchenne muscular dystrophy (DMD). None of the patients had cardiac symptoms and all of them exhibited normal electro- and echocardiographic findings. Electron microscopic examination of cardiac muscles from 4 patients with DMD disclosed proliferation of the mitochondria, changes in the cristae, abnormalities of the Z-bands, dilatation of the sarcoplasmic reticulum, deposition of glycogen, and changes in the nuclei. The most striking finding in these patients was that the residual bodies were increased and were observed mainly in the perinuclear region. These ultrastructural features suggest that an extreme exhaustion had already been present in myocardial tissue of the patients prior to the onset of cardiac symptoms.

Adolescent↗
PubMed1988

Peripheral neuropathy in four cases of group A xeroderma pigmentosum.

We describe the clinical features and findings of biopsied sural nerves of 4 cases of xeroderma pigmentosum. Nine genetic forms of xeroderma pigmentosum have been reported by complementation studies. These four cases were diagnosed as Group A xeroderma pigmentosum by complementation studies using cultured skin fibroblasts. All cases had delayed mental and motor development in areas such as head control over 4 months of age and walking without support over 18 months of age. Three cases had the gradual onset of a gait disturbance between 6 and 9 years of age. Motor conduction velocity and sensory conduction velocity of the ulnar nerve were slightly delayed. The sural nerve of the slightly impaired patient showed a normal density of myelinated fibers, but a selective reduction of the large myelinated fibers with zebra-body-like structures in Schwann cell cytoplasm. The population density of all nerve fibers was severely diminished in the severely impaired cases. Ultrastructural observation disclosed many denervated Schwann cells and pockets of collagen isolated by loops of denervated Schwann cell cytoplasm. These findings suggest that the degenerative process in peripheral nerves of xeroderma pigmentosum is axonal. Peripheral neuropathy in Group A xeroderma pigmentosum resembles that of patients with ataxia telangiectasia who are known to have a defect in the repair mechanisms of their DNA in cultured skin fibroblasts.

Adolescent↗
PubMed1986

Focal circumvention of blood-brain barrier with grafts of muscle, skin and autonomic ganglia.

The efficacy with which circulating horseradish peroxidase (HRP) spreads from transplants into the brain's interstitial spaces (IS), was assessed by 3 factors: graft type, site and age. Pieces of skeletal muscle, skin or entire superior cervical ganglion (SCG) were inserted into the IV ventricle (ventricular) or substance of the brain (parenchymal). The age of the grafts, i.e. the intervals after transplantation, were 1, 3, 6 and 12 months. Generally, HRP spread into the IS to about the same extent from ventricular muscle and skin autografts--1 mm, but less from parenchymal SCG allografts--0.5 mm. The spread from all grafts--ventricular and parenchymal--diminished with time. Exudation distance from muscle was the same as that from skin grafts for the first 6 months, but by 1 year, the penetration was significantly greater from muscle than from skin transplants. The flow of HRP was more extensive from parenchymal SCG grafts than from parenchymal muscle and skin grafts at 6 and 12 months. In some of the 6 and 12 month old parenchymal grafts of muscle and skin, no detectable HRP was extravasated. HRP consistently penetrated the brain more deeply from ventricular skin and muscle grafts than from parenchymal ones because more tissue mass survived in ventricular than in parenchymal autografts. Though care was taken not to damage the brain surface during ventricular insertion, there was a consistent, vigorous, collateral sprouting of, as yet unidentified, cranial nerves. These sprouts innervated muscle and skin autografts which, consequently, were able to survive for at least 1 year and contained vessels permeable to HRP. Allografts of muscle between inbred strains did not become innervated, survived for only 2 months and contained the central, barrier type of vessels, but not their intrinsic, permeable type. Thus, it is the muscle cell or its basal lamina within muscle grafts that determines the type of surviving vessel. In SCG allografts, even when all their ganglion cells had disappeared, leaving only connective tissue, Schwann cells and their basal lamina, the ganglion's capillaries survived and remained permeable to HRP. Therefore, the characteristics of the SCG vessels are determined by the Schwann cell-fibroblast milieu rather than the neuronal one.

Animals↗
PubMed1986

Muscle grafts as entries for blood-borne proteins into the extracellular space of the brain.

Nuchal muscle autografts of two different sizes were transplanted into rat brain parenchyma (intraparenchymal, 1.5 X 1.5 X 1 mm) and onto the surface of the brain stem (intraventricular, 2 X 2 X 1 and 1.5 X 1.5 X 1 mm). The vasculature of the transplants retained its permeability to proteins. Exogenous, intravenously injected horseradish peroxidase (HRP) and endogenous immunoglobulins (IgG) crossed the vessels of the grafts to enter the surrounding brain tissue 1 and 3 months after transplantation. HRP infiltrated about 0.46 to 4.6 mm into the extracellular spaces around the grafts 60 minutes after its intravenous injection. The penetration of HRP depended on the size and age of the graft. Infiltration was greater in 1-month-old rats with slightly larger intraventricular grafts than in those with smaller grafts. There was a tendency for the penetration of HRP to be greater from 1-month-old grafts than from 3-month-old grafts, but the difference was not statistically significant, except for the horizontal vector of spread in the intraparenchymal group. Although endogenous IgG infiltrated the surrounding brain tissue, its penetration was very limited in comparison with that of HRP. The results suggest that muscle grafts could be used as a readily available and accessible means of circumventing the blood-brain barrier selectively and focally.

Animals↗
PubMed1985

Angiographically occult angiomas: a report of thirteen cases with analysis of the cases documented in the literature.

Thirteen cases of angiographically occult angioma (AOA) are reported. Nine of these presented with intraparenchymatous hemorrhage, and the other 4 patients had epilepsy. The pathological diagnosis was arteriovenous malformation in 12 cases and cavernous angioma in 1. All surgical specimens but 2 contained hemosiderin pigment. In addition to these 13 cases, we reviewed 159 cases of AOA reported in the literature and analyzed them in terms of age, sex, symptoms and signs at admission, computed tomographic findings, location and size of angioma, history of previous and recurrent hemorrhage, type of hemorrhage, and outcome of operation to determine the characteristics of AOAs. The results of these analyses are described in detail, and the indications for surgical treatment of suspected AOAs are discussed. Our microsurgical technique for detecting the angioma within or adjacent to the hematoma is also presented.

Adolescent↗