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Biomedical subjects

H Handa

Publications and source records attributed to H Handa.

At least 433 records · Page 24Linked to original sources
PubMed1983

Characteristic immunological responses to an experimental mouse brain tumor.

Immunological responses to an experimental brain tumor of mice [the 20-methylcholanthrene-induced malignant glioma, 203-glioma)] were investigated. The killer T-cell activity of spleen cells, which was specific against 203-glioma cells, began to be severely impaired 2 weeks after intracranial inoculation; this impairment was concurrent with increased intracranial pressure, which was due to developing tumor growth. On the other hand, the killer T-cell activity continued for over 4 weeks in mice inoculated with the mitomycin C-treated tumor cells. Surface marker analysis showed that Lyt-1-2,3+ killer T-cells were predominant in intracranial tumor-bearing mice, whereas both Lyt-1-,2,3+ and Lyt-1+,2,3+ killer T-cells were equally present in s.c. tumor-bearing mice. The effects of adult thymectomy on the immune responses against 203-glioma were also investigated in intracranial and s.c. tumor-bearing mice. In both the intracranially and s.c. inoculated groups, killer T-cell activity was increased in mice thymectomized before 3 weeks and decreased in mice thymectomized before 10 weeks. In these mice, Lyt-1+,2,3+ killer T-cells were not detected, which suggests strongly that the progenitors of Lyt-1+,2,3+ killer T-cells are short-lived lymphocytes in contrast to those of Lyt-1-,2,3+ killer T-cells, which survive more than 10 weeks after adult thymectomy.

Animals↗
PubMed1983

[Meningioma of the sphenoid ridge recurring into the pterygomaxillary fossa following craniotomy. A case report and surgical approach].

Meningiomas sometimes invade into the surrounding structures, especially into the sinuses, and show remote extracranial metastasis. Meningiomas of the sphenoid ridge sometimes extend and invade into the cavernous sinus, diaphragma sellae, sphenoid and ethmoid sinuses, orbit and the pterygomaxillary fossa. A case of the tumor of the right sphenoid ridge, which recurred into the orbit and the pterygomaxillary fossa two years after the total removal, was presented. Histological examinations of both the first and second tumor showed meningotheliomatous meningioma. A 61-year-old female was admitted on January 17, 1980 with a complaint of left hemiparesis, memory disturbance, disorientation and incontinentia urinae. Right carotid angiography and CT scan showed a large high density mass in the right middle cranial fossa, which was totally removed. After the operation, the neurological status rapidly improved and she spent an uneventful life until February 1982 when she noticed right exophthalmos, ophthalmoplegia and visual loss. Right CAG and CT scan at the second admission showed a strongly enhanced mass in the right orbit and pterygomaxillary fossa. Severe destruction of the posterolateral wall of the right orbit and the floor of the right middle cranial fossa was also noticed. The tumor was totally removed, using modified Dieffenbach-Weber-Fergusson approach, which is usually used for the carcinoma of the maxillary sinus. By this approach, we could easily reach the pterygomaxillary fossa, that is, the floor of the middle cranial fossa and the posterolateral wall of the orbit. This approach seemed to be very useful for the removal of the tumors of the skull base.

Craniotomy↗
PubMed1983

[Computerized tomographic evaluation of 33 cases of craniopharyngioma, with special reference to unusual extension, iso-dense cyst and homogeneous enhancement].

Although craniopharyngiomas are widely known to exhibit three basic CT characteristics; calcification, cyst(s) and contrast enhancement (CE), several cases with atypical CT manifestations have been reported lately. These atypical manifestations can be classified into unusual extensions of the tumors, high dense cyst and marked homogeneous CE. The CT scans obtained in our recent series of 33 craniopharyngiomas were evaluated to analyze tumoral extensions, cyst density and CE. Cystic tumors were much more frequent than solid tumors (Table 1); 13 cases (39%) were exclusively cystic, 15 cases (45%) equally cystic and solid, and 5 case (15%) solid. Calcifications were present in 80% in children and 39% in adults. Unusual extensions were noted in 7 cases (Fig. 2,3,4); anteriorly to the frontal fossa (5 cases, 15%), laterally to the temporal fossa (1 case, 3%) and posteriorly to the posterior fossa (1 case, 3%). All these tumors were either pure cystic or equally cystic and solid. Cystic portions were detected in the tumors of 28 cases (Table 2). Although the majority of the cystic portions (22 cases, 79%) were low density, iso-dense cysts were observed in 6 cases (21%). Out of 20 cases exhibiting solid portions in the tumors, high density areas (calcified masses) were detected in 3 cases and mixed density areas in 17 cases (Table 3). While these 17 cases showed CE, marked homogeneous CE were noted in 5 cases (29%). Since the advent of high resolution computerized tomography, most of typical craniopharyngiomas can be differentiated from other parasellar lesions; pituitary adenoma, meningioma, optic or hypothalamic glioma, aneurysm, dermoid, epidermoid, arachnoid cyst, germinoma and so forth.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1983

[Pseudotumor cerebri].

Although pseudotumor cerebri is not the primary subject for the neurosurgical treatment, it is of clinical significance on differentiating from brain tumors and other similar lesions. The literatures concerning its clinical features and pathophysiology are reviewed with short summary of our eighteen cases. The incidence of pseudotumor cerebri, based on the clinical reports and our experience, seems to be low in Japan, which may be due to difference on races and/or diet. The visual acuity impairment is not always "benign" on its course, in contrast to other symptoms related to the increased intracranial pressure. CT scan is most useful for evaluating the ventricular size and abnormal densities. Contrast enhancement is required for detecting abnormal enhanced lesions. Angiography may disclose the dural sinus occlusion and/or dural arteriovenous malformation. Continuous measurement of intracranial pressure can show irregular change from high pressure to normal with or without episodic elevation in each case and on each day. It is reported that there is no rise of intracranial pressure in some cases. There are also some reported cases without papilledema. Various factors including increased blood volume, brain edema and impaired absorption of cerebrospinal fluid may play some role on the development of pseudotumor cerebri. The precise mechanism of small ventricle associated with impaired absorption of cerebrospinal fluid is still unclear. Further study about absorption and outflow resistance of cerebrospinal fluid, and alteration of blood volume and brain water content may resolve the pathophysiology of pseudotumor cerebri.

Adolescent↗
PubMed1983

New treatment of cerebral vasospasm with Fluosol-DA 20%: protective effect on cerebral ischemia and change of cerebral blood flow (CBF).

It was found that Fluosol-DA 20% relieves human acute cerebral ischemia resulting from vasospasm in 62% of the cases. However, several problems were encountered during the investigation. The efficacy of the solution was temporary, that is, within 24 hours. This is considered logical because perfluorochemical particles are eliminated fairly rapidly from the circulating blood. Successive administrations should be necessary until cerebral vasospasm is remitted. Another problem is that it is not clear whether the doses of the solution given in this study (10 ml/kg/day) are sufficient or not, since the depth of the cerebral ischemia is considered to vary depending on the case. It might be necessary to change the volume of the solution given in accordance with the depth of the ischemia of each patient.

Blood Substitutes↗
PubMed1982

On the mechanism of heparin-induced potentiation of platelet aggregation.

The role of antithrombin III (AT III) in heparin-induced potentiation of platelet aggregation was investigated using purified AT III and AT III depleted plasma. When ADP or epinephrine was added to citrated platelet rich plasma (PRP) one minute after addition of heparin, marked enhancement of platelet aggregation was observed, compared with the degree of platelet aggregation in the absence of heparin. However, heparin exhibited no potentiating effect on ADP- or epinephrine-induced platelet aggregation when platelets were resuspended in AT III depleted plasma prepared by immunosorption using matrix-bound antibodies to AT III. When purified AT III was added to AT III depleted plasma at a concentration of 20 microgram/ml, potentiation of platelet aggregation by heparin was clearly demonstrated. These results suggest that the effect of heparin on platelet aggregation is also mediated by AT III.

Adenosine Diphosphate↗
PubMed1982

Management of spontaneous carotid-cavernous fistulae.

Fifteen cases of spontaneous carotid-cavernous fistulae, including 4 patients with spontaneous cure and 8 treated with electrothrombosis, are reviewed. Careful angiographic observation will verify closure of the fistula. Aggravation of visual and/or ocular symptoms can also develop with spontaneous carotid-cavernous fistulae. Recurrence of symptoms and development of collaterals were noted, especially after carotid ligation or embolization of the external carotid artery. Electrothrombosis successfully closed the fistulae in 7 patients. The internal carotid artery was occluded in 1 patient who had a preoperative carotid stenosis at the cervical level. The ability to differentiate angiographically between single and multiple fistulae provides a new possibility that spontaneous carotid-cavernous fistulae can be treated with detachable balloon catheters.

Adult↗
PubMed1982

The Nd:YAG laser in neurological surgery.

The Nd:YAG laser has been applied in microneuro-surgery and has been found to be quite effective in removing had and hemorrhagic tumors such as meningiomas, tumors of the deep skull base, or tumors deep in the ventricle. Another indication for the use of the Nd:YAG laser is to open the thick sellar floor in transsphenoidal operations.

Adenoma↗