Biomedical subjects
Publications and source records attributed to T Ebina.
Effect of Neocarzinostatin (NCS) on microtubules was examined both in vitro and in vivo. Although NCS had no effect on microtubule assembly in vitro nor dissociated cytoplasmic microtubular network in vivo, microtubular network appeared to be changed to coarse form in NCS-treated 3T3 and HeLa cells. Effect of NCS on microtubules was discussed in comparison with colchicine.
174 cases of middle cerebral artery aneurysm submitted to surgical operations without using microscope were reviewed. At operation, the head is set on the neutral and slightly chin up position, not turned to any directions. Small craniotomy, which is about half as much as the ordinary unifrontal craniotomy, is performed. The merit of our method is as follows; the M1 portion (Fisher) of the middle cerebral artery runs horizontally, so that we can keep the parent artery during the operation, and owing to the chin up position the strong retraction of the frontal lobe can be avoided. Of 174 cases, 9 were dead (mortality rate 5.2%) and 18 were poor (10.4%). Bad operative outcome is due to the obstruction of the middle cerebral artery around the aneurysmal neck. Therefore, we should always keep in mind to preserve the blood flow of the parent artery as well as that of its branches. Study was made mainly on this point of view such as the general technical process of the aneurysmal neck treatment, the treatment of the cases with severe arteriosclerosis and with large aneurysms having the blood coagula inside.
213 cases of so-called posterior communicating artery aneurysm submitted to surgical operation without using microscope were reviewed from the technical point of view. Aneurysm project boradly to two directions, i.e. postero-inferior and lateral directions. We have treated these anuerysms with two very distinct operative approaches in order to reach the aneurysmal neck from the right angle. Frontal approach is used for the aneurysms projecting laterally. In contrast, the aneurysms projecting postero-inferior are reached laterally by mobilizing the tip of the temporal lobe. Of 213 patients, 15 died (mortality rate 7.0%) and 19 were poor (8.9%). The operative result of the cases in which the aneurysm ruptured during the exposure of the aneurysmal neck was poor. Therefore, intensive care is emphasized to avoid the aneurysm rupture during surgery. Other important technical points which affect the operative results were discussed.
In order to examine the involvement of microtubules in the virus-induced cytopathic effect (c.p.e.), the effect of virus infection on the formation of microtubular paracrystals (PC) induced by 10 microgram/ml of vinblastine sulphate in HeLa-S3 cells was examined by phase-contrast microscopy. In poliovirus-infected cells, c.p.e. (cell rounding) and the inhibition of PC formation proceeded in parallel, starting 4 h post-infection. In Sendai virus-infected cells, however, PC formation was not inhibited even 24 h post-infection when most infected cells clearly showed c.p.e. (syncytial formation). In adenovirus-infected cells, the inhibition of PC formation was observed 9 h before the appearance of c.p.e. Cytosine arabinoside (ara C) did not block the inhibition of PC formation in infected cells, but blocked the appearance of late c.p.e. (nuclear alteration). Cycloheximide blocked both the inhibition of PC formation and the induction of late c.p.e. These results suggest that an early protein synthesized de novo by adenovirus is required for direct or indirect inhibition of the microtubular PC formation. Furthermore, on ultraviolet (u.v.) inactivation of adenovirus both activities (induction of early c.p.e. shown by shrinkage of cytoplasm, and inhibition of PC formation) followed the same inactivation curve and were inactivated at a slower rate than viral infectivity and the activity leading to late c.p.e. The u.v. light sensitive target responsible for the induction of early c.p.e. and the inhibition of PC formation is about 20% of that for infectivity and is in accord with the genome size of the early functioning virus genes. In herpes simplex virus (HSV)-infected cells, the inhibition of PC formation, the appearance of c.p.e. (cell rounding and disappearance of nucleoli) and the synthesis of V antigen proceeded in parallel. These three functions of HSV were not blocked in infected cells even when the de novo synthesis of virus DNA was inhibited by ara C or phosphonoacetic acid (PAA), whereas these three functions were blocked by cycloheximide, suggesting that a protein coded by the input virus genome early after infection inhibits the microtubular PC formation and is responsible for c.p.e. From the u.v. inactivation curve of HSV, it was confirmed that only one-tenth of virus genome was responsible for both activities (induction of c.p.e. and inhibition of PC formation).
The characteristic ultrasono-cardiographic (UCG) findings of prolapsed mitral valve were studied in 9 cases by means of ultrasonocardiotomography (UCT). The changes in degree and shape of the prolapsed valve were examined and the leaflet involved was identified. Of the 9 cases, 5 had prolapse of anterior, 3 had that of posterior leaflet and 1 had both. In all cases with midsystolic click and late systolic murmur or pansystolic murmur with late systolic accentuation, the prolapse of anterior leaflet was observed on UCT, and though UCG disclosed midsystolic buckling it was difficult to determine the exact timing of the prolapse by UCG alone. In the cases with rheumatic mitral regurgitation, the prolapse of posterior leaflet and the ballooning of anterior leaflet could easily be found on UCT, but the detection of the above-mentioned 2 findings was difficult by UCG alone. Three of the 9 cases were found to have prolapse of posterior leaflet by left ventriculography, whereas these 3 had prolapse of anterior leaflet on UCT. Hence, the diagnosis of prolapsed mitral valve based on the cineangiography may require re-evaluation.
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Two children of normal parents had "Dandy-Walker syndrome" (cystic dilatation of the 4th ventricle with incomplete development of the cerebeller vermis). Both cases were admitted to our hospital in neonatal period, because of apneic spell. Air study showed the enlargement of the 4th ventricle in both cases. One case (22 days after birth, male infant) was operated by occipital craniotomy, and cystic membrane of the roof of the 4th ventricle was removed. But his head was growing rapidly in size, which suggested hydrocephalus. He died of pneumonia at 70 days after V-P shunt operation. At autopsy, defect of the cerebellar vermis and tonsil, involving the enlargement of the 4th ventricle was found. Another case, younger sister of the previous one, was complicated by occipital meningocele, which did not communicated with ventricular system. Her occipital tumor was removed, and now, she is growing normally in body size, but does not react to the visual stimuli with considerable psychomotor retardation. In our cases, occlusion of the foramina Luschka and Magendie was not present. So, we have come to the conclusion that primary underdevelopment of the cerebellum is of major importance for understanding of the etiopathogenesis of this syndrome.
In the past 14 years, 1000 cases of aneurysms were submitted to surgical operations without using microscope. In this report 346 cases of anterior communicating artery aneurysms were studied. The operative result at discharge was as follows; 19 cases (5.5%) were dead, 27 poor, 39 fair, 64 good and 197 excellent. In the follow-up, out of 300 cases 29 were dead (16 were related to the operation), 7 were poor, 13 fair, 26 good and 226 excellent. Out of 19 dead cases during hospitalization, 14 were operated within two weeks after SAH. Ten out of 14 cases operated within two weeks died due to vasospasm and all these 10 cases were operated between five to 11 days after SAH. These results and results of ultra-early surgery on other sites of aneurysm suggested that the surgery should be avoided on the cases from third to 10th day after SAH. After the 3rd day, the operation should be decided by taking vasospasm into consideration. If the SAH attack is a mojor one accompanying loss of consciousness more than one hour, the operation should be postponed until the 14th day. If the SAH attack is a moderate one accompanying loss of consciousness within one hour, it should be postponed until the 9th or 10th day. When the SAH attack doesn't accompany loss of consciousness, the surgery can be done any time. If stiff neck is obvious, it should be performed on the 9th or 10th day. Our approach for anterior communicating artery aneurysms is a interhemispherical approach following the bifrontal craniotomy. Hypothermic anesthesia around 27 degrees C was used in order to prolong the temporary occlusion time until 1971. Since 1972, 500 approximately 800 ml of 20% mannitol was applied intravenously for preventing the infarction following the temporary occlusion under the normothermic general anesthesia. Details of the operative records of 346 cases were analyzed and our operative method, technique and technical points were discussed.
Twenty-eight cases after subarachnoid hemorrhage due to ruptured intracranial aneurysms was undergone third ventriculostomies as the reason that the development of postoperative CSF disturbances was determined to be highly probable. The indication and value of third ventriculostomy was discussed considering various clinical and operative findings. Postoperatively, six of the 28 cases required ventriculoperitoneal shunt operation. Although temporary disturbances of serum electrolytes was noted in three cases, no other side effects was attributed to third ventriculostomy. During hospitalization, no fatalities occured following third ventriculostomy. The addition of third ventriculostomy to surgery for ruptured intracranial aneurysms in highly recommended, especially in cases strongly indicating the possible occurrance of postoperative CSF flow disturbances.
A simple method for microinjecting isolated chromosomes into a single living cell under an inverted microscope has been developed. Of the 368 injected cells, 85 were able to form a colony and could be cloned. Clones of Chinese hamster V79 cells microinjected with chromosomes isolated from murine D56 cells [V79 (D56) cells] were tested for tumorigenicity in immunodeficient nude mice and for colony-forming ability in soft agar. Untreated recipient V79 cells were highly tumorigenic and had a high colony-forming ability in soft agar. In contrast, two out of the 21 microinjected clones tested were non-tumorigenic in nude mice and had only weak colony-forming ability in soft agar. The chromosome banding pattern was analyzed in microinjected clones and tumors derived from cells of these clones. In cells of the two non-tumorigenic clones, a telocentric chhromosome 1 (t1) was specifically involved in translocations with other chromosomes or chromosome fragments. In all tumor cells obtained from nude mice, a supernumerary piece or a whole biarmed chromosome 14 (b14) was specifically found. The results suggest that the t1 chromosome bears the gene which controls in vitro transformation and that the additional genetic change, i.e. the extra piece of b14 chromosome, was required for tumor formation in vivo.
A new noninvasive method of measurement of the intracardiac blood flow by means of ultrasound techniques is described. In this system the "M-sequence modulated Doppler method" and the method of ultrasonotomography are used in combination. An arbitrary space within the heart can be selected by ultrasonocardiotomography and the blood flow profiles can be observed by the "M-sequence modulated Doppler method." The new Doppler flow meter system described in this paper can be applied not only for the diagnosis of heart diseases, but also for the study of pathophysiology of the blood flow and of the factors responsible for the dilatation of the heart. Further studies are required from the viewpoints of medicine and engineering to accumulate sufficient data before routine application of the method described in this paper is fully warranted.
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The effects of an antitumor antibiotic, neocarzinostatin (NCS), on the surface immunoglobulin central capping induced by anti-immunoglobulin M antibody on Daudi cells and on the cell spreading of trypsinized HeLa-S3 cells were examined. Pretreatment of Daudi cells and HeLa-S3 cells with NCS, 5 to 30 micrograms/ml, for 4 hr inhibited cap formation and cell spreading, respectively. It was shown that there is a direct relationship between the dose and the degree of inhibition. Inhibitors of DNA synthesis such as bleomycin, mitomycin C, and 1-beta-D-arabinofuranosylcytosine showed no inhibitory effect on cap formation or cell spreading. However, known microtubule-acting agents such as colchicine and vinblastine sulfate completely inhibited both capping and cell spreading at a dose of 10 micrograms/ml. In view of the fact that 10 micorograms NCS per ml also inhibit the formation of microtubular paracrystals induced by vinblastine sulfate in HeLa-S3 cells and that other agents known to influence microtubule function such as local anesthetics and calcium ionophores also inhibit both paracrystal formation and cap formation, these new observations add further support to our hypothesis that NCS affects microtubular proteins transmembranously in vivo.
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The effect of an antitumor antibiotic, neocarzinostatin (NCS), on the formation of microtubular paracrystals (PC) induced by vinblastine sulfate, 10 mug/ml, in HeLa-S3 cells was examined by phase-contrast microscopy. The pretreatment of HeLa-S3 cells with NCS, 5 to 50 mug/ml, for 4 hr prevented the PC formation, and there was a dose response of NCS to the degree of inhibition. When the same inhibitory effect on PC formation was examined with other antitumor agents at high doses (50 mug/ml), colchicine was found to be one of the most effective agents, like NCS. Puromycin, antimycin, adriamycin, cytochalasin B, and cycloheximide revealed moderate activity, and the other antibiotics, such as mitomycin C, bleomycin, and rifampicin, did not show any effect at all. NCS was a unique antibiotic that inhibited PC formation among inhibitors of DNA synthesis. It was suggested that NCS affects the microfibrillar-microtubular proteins system in vivo, resulting in the inhibitions of organization of spindle fibers from microtubules at the G2 phase in HeLa cells.
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