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Biomedical subjects

K Shimokawa

Publications and source records attributed to K Shimokawa.

At least 163 records · Page 9Linked to original sources
PubMed1980

[Intracerebral germinoma developing in the right basal ganglia--report of a case followed up by CTscan and review of the literature (author's transl)].

Recently, a case of intracranial germinoma in the right basal ganglia was experienced in our department. He was a 14-years old boy with left motor hemiparesis. On repeated CT studies (7 times), developmental process of the tumor was observed for about 2 years. The tumor developed from the right putamen and invaded toward it's neighboring area (right basal ganglia, thalamus and hypothalamus). As the tumor grew larger, multiple cysts were formed in the tumor tissue and dislocation of ventricles occurred. On 21 December 1978, right temporal craniotomy was performed and a piece of the tumor was removed. It's tissue was diagnosed as germinoma by pathohistological examination. As the effect of postoperative 60Co irradiation and chemotherapy (Vicristine, CCNU), tumor stain (high density area) on CT scann disappeared and remained only as a well margined low density area. On CT scan in September 1979, recurrence sign was not noted. Clinical features of the germinoma located in the basal ganglia has not been well known, because of it's rarity. As a result of the survey of 7 cases reported in the Japanese literature and our case, it has been made clear that most of them are characterized by motor hemiparesis in the early stage, not accompanied by intracranial hypertension.

Adolescent↗
PubMed1980

[Trigeminal neurinoma with massive extracranial extension, report of a case (author's transl)].

It appears that more than a hundred cases of trigeminal neurinomas have hitherto been reported, but massive extracranial extension of a benign neurinoma into the sphenoid sinus and soft part tissue of the neck is unusual. A 36-year-old woman was admitted to our clinic with complaints of left blindness, vertigo and left nasal stuffiness. Neuroradiological examinations, including plain craniography, angiography and CT, showed a huge mass which destroyed the left middle fossa and extended into the left sphenoid sinus and soft part tissue of the neck. On December 14, 1978, left fronto-temporal craniotomy was carried out, and intracranial portion of the tumor was removed, leaving its extracranial portion intact. Pathological examination revealed benign neurinoma. The postoperative course was uneventful except temporary left total ophthalmoplegia. It was emphasized that, to obtain cure for trigeminal neurinoma, early diagnosis is extremely important, and, for this purpose, CT, including coronal one, was considered to be one of the most useful examinations.

Adult↗
PubMed1979

Schwannoma of the sellar region.

A 25-year-old woman who had experienced brief periods of loss of consciousness and grand mal seizures was found to have a midline mass in the sellar region as evidenced by computer tomography and angiography. Preoperatively, it was thought to be a meningioma but histologically and ultrastructurally it turned out to be a Schwannoma. Since cranial nerves were not involved, clinically or morphologically, this nerve sheath tumour could have originated from Schwann cells of sensory, possibly trigeminal, nerves, vasomotor nerves, or ectopic Schwann cells.

Adult↗
PubMed1979

[Cerebral degeneration in Down's syndrome].

Clinical and neuropathological findings of a 63-year-old male and a 25-year-old female with Down's syndrome are presented. Neuropathological examination of the older patient revealed intense features of Alzheimer's disease or senile dementia, including congophilic angiopathy and extensive mineral deposits in the globus pallidus and in the white matter of the cerebellum. In the hippocampus of the younger patient, plaque-like bodies and a few neurofibrillary tangles were found. From a survey of the cases hitherto reported in the literature it appears that among patients over 50 years of age it is common to encounter pathological features typical of Alzheimer's disease or senile dementia, that plaque-like bodies may occur in the second decade, neurofibrillary tangles in the third decade and a congophilic angiopathy in the fourth decade. The congophilic angiopathy is a frequent finding. Due to their high frequency, calcium or calciumlike deposits are regarded as important histopathological substrates of Down's syndrome. The clinical symptomatology of the long-surviving patients with Down's syndrome is that of a non-characteristic brain aging process and differs from that of the typical Alzheimer's disease. Organic dementia is not regularly found. Altogether, the anatomical findings in adult patients with Down's syndrome indicate a premature aging of the brain, which becomes more significant and widespread with increasing age.

Adult↗
PubMed1979

[Nuclear spheroids in neurons of the human hypothalamus].

Morphological structure, distribution and frequency of the so-called "nuclear spheroids" have been studied in the human hypothalamus. The following results were obtained: 1. By light microscopy, the nuclear spheroids turned out to be small or large spheroid bodies inside the nucleus. They are almost homogeneous, rarely granular, vacuolar or reticular and occasionally they are multiple. They are best stained with the cresyl-violet technique. They do not exhibit any histochemical pecularities. Aside from typical nuclear spheroids, irregularly shaped nuclei were frequently seen, associated with increased nuclear folds, transitional stages between nuclear folds and nuclear spheroids were also present. Certain microscopic features suggest invagination and displacement of nuclear membrane and cytoplasm into the karyoplasma. 2. By electron microscopy, the nuclear spheroids consist of nuclear membranes and cytoplasmic constituents. They, therefore, actually represent cytoplasm protruding into the cell nucleus. 3. The nuclear spheroids occur almost regularly and most frequently in the ventromedial field of the tuber cinereum, foremost in the infundibular (= arcuate) nucleus. They numerically increase during life. They are rarely found in the ventromedial nucleus but do occur in most of the adults. In the paraventricular nucleus, the supraoptic nucleus, the lateral nuclei tuberis, and in lateral hypothalamic nucleus, they are found by far less often. They scarcely develop in the preoptic area, in the dorsal field, in the tubero-mamillar complex, in the parafornical nuclear groups, in the premamillary nucleus and in the mamillary nuclei. 4. Within the infundibular (= arcuate) nucleus, the nuclear spheroids are particularly numerous in the basal and basolateral regions, whose neurons, under certain functional conditions--such as the Sheedan syndrome, in the menopause and in association with pituitary neoplasms-, appear hypertrophic. Within the hypertrophic neurons of this region, which we designate the subventricular part of the infundibular nucleus, nuclear spheroids are definitely more frequent, and they are of the large type. 5. A separation of the subventricular part based on the distributional pattern of the nuclear spheroids indicates a pathological karyoarchitectonics which supplements the normal karyoarchitectonics (Bachmann, 1948). 6. The nuclear spheroids seem to be associated with increased neuronal activities, for their frequently strongly correlates with the neuronal hypertrophy which expresses enhanced neuroendocrinological activity.

Adolescent↗
PubMed1978

The ultrastructure of the retina in adult metachromatic leukodystrophy.

A 46-year-old woman afflicted with biochemically proven metachromatic leukodystrophy had only mild optic atrophy shortly before her death. Repeated earlier ophthalmoscopic examinations had not revealed any retinal abnormalities. Light microscopy of the retina showed strong acid phosphatase activity in both enlarged ganglionic cells and pigment epithelial cells. Demyelination of both optic nerves was not noted. Ultrastructurally, membranous lysosomal residual bodies were confined to ganglionic cells. We found lipofuscin material in pigment epithelial cells, but also within metachromatic leukodystrophy-specific residual bodies of ganglionic cells. The presence of lipofuscin represents the "wear-and-tear" phenomenon, possibly enhanced by the metachromatic leukodystrophy.

Acid Phosphatase↗
PubMed1977

[Calcified epidural hematoma-report of a case incidentally found 16 years after head injury (author's transl)].

A calcified epidural hydroma, or old hematoma, was incidentally found in the left parietal region of a 55-year-old man presenting status epilepticus due to uremia after a lapse of 16 years following head injury. The hydroma (10x7x1.2 cm) was extirpated operatirelly. There was an extensive calcificantion in the wall, and the outer wall showed bone-like metaplasia and hemosiderin deposit. No skull fracture was discernible. The dura and the brain surface neighboring the hydroma were gloslsly normal. The patient eventually died of uremia.

Calcinosis↗
PubMed1976

Cystic goiter with squamous-cell metaplasia--case report and comment on origin of squamous-cell cyst.

A 53-year-old woman with a left unilocular cystic goiter of the size of a small orange was reported. Approximately four-tenths of the innter surface was lined with several layered squamous epithelium with few follicles remaining. A gradual metaplastic transition from the follicular epithelium to the flattened cuboidal and to the squamous epithelium was observed. The ultimobranchial body has been understood to be a possible origin of an entirely squamous cell cyst of the thyroid, three of which have been reported. The difference between the ultimo-branchial and metaplastic origins will be discussed, and a new designation-primary (ultimo-branchial) and secondary (metaplastic) squamous-cell cyst will be proposed.

Animals↗
PubMed1976

A spontaneous transplantable osteogenic sarcoma in AKR/Ms mice.

A transplantable osteogenic sarcoma originally arising in the right femur of an AKR/Ms male mouse is described. The original tumor showed a conspicuous bone and cartilage formation, but the capability of forming the bone was lost in the 4th transplant generation and that of cartilage formation was lost in the 7th generation. Alkaline phosphatase activity was histochemically demonstrated in only a few tumor cells, and the activity did not rise in the host serum. Intracisternal type-A particles of an average diameter of 70 nm were abundant in the rough endoplasmic reticulum, while type-C particles were rarely found to be budding from the cell surface or free in the extracellular spaces by electron microscopy. Three of the 27 thymectomized AKR mice that had been neonatally injected with cell-free material of the transplanted tumor developed osteomas, but no osteogenic sarcoma was found.

Alkaline Phosphatase↗
PubMed1975

Polynucleotides. XXVIII. Stimulation of the binding of aminoacyl-tRNA to ribosomes by tri- and polynucleotide analogs.

Messenger activity of synthetic tri- and polynucleotide analogs was studied by binding of 14C-labeled aminoacyl-tRNAs to ribosomes in the presence of the analogs. Synthetic messengers used were: poly(A) analogs in which adenosine was replaced by tubercidine (I), 3-deazaadenosine (II), 1-deazaadenosine (III) and 2-methyladenosine (IV); copolymers of adenosine and aristeromycin (V); cyclic triadenylate (VI); the heptanucleotide of 6,2'-O-cyclouridine (VII); the pentanucleotide of 8,2'-S-cycloadenosine (VIIIa); A-U-G analogs in which adenosine was replaced by 8,2'-O- and S-cycloadenosine (VIII), 8,5'-O- and S-cycloadenosine (IX); 8-oxyadenosine (x); 8-bromoadenosine (XI) and formycine (XII). Among these oligo- and polynucleotides, analogs which contained nucleotides of anti conformation having appropriate bases for Watson-Crick type hydrogen bonding stimulated the binding of corresponding tRNAs to ribosomes.

Adenosine↗
PubMed1975

Effects of diethylstilbestrol and testosterone propionate implanted in the hypothalamus on spermatogenesis in rats.

Small quantities of diethylstilbestrol and testosterone proprionate were implanted into the hypothalamic arcuate nucleus of male rats of the Wistar-Imamichi strain at 43 days of age. The animals were sacrificed at 64 or 76 days of age. Diethylstilbestrol suppressed the development of all genital organs and disturbed spermatogenesis. The damage was found to have recovered slightly in rats sacrificed at 76 days of age. Testosterone propionate was also effective for the atrophy of some genital organs. Its influence was not so severe as that of diethylstilbestrol. It extinguished almost completely 33 days after implantation. On the contrary, the numbers of spermatogonia and spermatocytes per cross section of the seminiferous tubule were smaller at 76 days than at 64 days of age. The diameter of the seminiferous tubule in the rat implanted with testosterone propionate was longer at 76 days than at 64 days of age. Therefore, the tubular diameter did not always represent the quantity or quality of spermatogenesis. The results also suggested that spermatogenesis might have been disturbed in some of the rats in which androgen was considered to be secreted almost normally.

Animals↗
PubMedDate not supplied

Hemodynamics of small hepatocellular carcinomas (5 cm or less in diameter): cases with discrepant findings between dynamic MR images and hepatic arteriograms.

BACKGROUND: The degrees and patterns of contrast enhancement of small hepatocellular carcinomas (HCCs) on dynamic magnetic resonance (MR) images were compared with those on hepatic arteriograms in 61 patients. METHODS: Dynamic MR imaging was performed within 1 week before hepatic angiography prior to treatment, 3-4 weeks after treatment, and then once every 1-3 months if necessary. Hepatic arteriography was carried out with a coaxial microcatheter inserted into the proper hepatic artery or its distal branches. RESULTS: In 58 of 61 cases, the degrees of contrast enhancement of the tumor in dynamic MR imaging were roughly consistent with those in hepatic arteriography before treatment. In the remaining three cases, however, the tumors were depicted as hyperintense in the arterial dominant phase of the dynamic MR imaging, whereas the tumors were not detected by hepatic arteriography. The tumor detectability is 97% by dynamic MR imaging and 92% by hepatic arteriography. Furthermore, when an HCC nodule was not clearly enhanced by hepatic arteriography after treatment, it was possible by dynamic MR imaging to obtain accurate information on whether the HCC nodule had parasitic arteries. CONCLUSIONS: Dynamic MR imaging was superior to hepatic angiography in contrast resolution. It was therefore considered to be useful in assessing the degrees and patterns of contrast enhancement of small HCCs before and after treatment.

Aged↗
PubMedDate not supplied

Lipiodol retention and massive necrosis after lipiodol-chemoembolization of hepatocellular carcinoma: correlation between computed tomography and histopathology.

This retrospective study examined the computed tomography (CT) criteria for judging the effectiveness of transcatheter arterial Lipiodol-chemoembolization (Lp-chemo-TAE) in 35 cases with hepatocellular carcinoma (HCC). Massive necrosis, defined as involving 97% or more of the HCC nodule, was observed in 15 cases after Lp-chemo-TAE, whereas nonmassive necrosis, defined as involving < or = 96% of the HCC nodule, was observed in the remaining 20 cases. In 12 of 15 cases (80%) with massive necrosis, uniform dense retention of Lipiodol (Lp) was observed throughout the HCC nodule on CT images 3-4 weeks after Lp-chemo-TAE as opposed to only one (5%) of 20 cases with nonmassive necrosis (p < 0.01). Eight of nine cases (89%) with massive necrosis had tumor attenuation values of 365 Hounsfield units (HU) or greater on CT images 3-4 weeks after embolization, as opposed to only four (27%) of 15 cases with nonmassive necrosis (p < 0.01). We conclude that the effectiveness of the Lp-chemo-TAE can be judged on CT from the degree and duration of Lp retention in the HCC nodule and the measurement of the attenuation value of the HCC nodule.

Carcinoma, Hepatocellular↗