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Biomedical subjects

K Takakura

Publications and source records attributed to K Takakura.

At least 397 records · Page 22Linked to original sources
PubMed1985

[Identification of 11-HETE in the rat brain and its relevancy to ischemic cerebral edema].

Eicosanoids are thought to be important in the pathogenetic mechanism of ischemic brain damage. But little is known about lipoxygenase products and their roles in brain. In the present study, lipoxygenase metabolism in the brain and its relevancy to ischemic brain edema were studied using high performance liquid chromatography (HPLC) and gas chromatography-mass spectrometry (GC-MS). The rat middle cerebral artery (MCA) occlusion model was used because the time course of ischemic edema formation has been well known. The rat brain was fixed by in situ freezing 24 and 72 hours after MCA occlusion, and removed. Identification and quantitative analysis of hydroxyeicosatetraenoic acids (HETEs) in normal and ischemic brain homogenates was performed by HPLC and GC-MS. The rat brain was divided into the microvessel (MV) fraction and the rest. Then the same analysis was carried out in the both fractions obtained from the normal rat brain. Only 11-HETE was detected in the normal and ischemic brain. Quantitatively, normal brains contained 1288 +/- 66 (mean +/- SE) of 11-HETE ng/g wet weight, while the hemispheres rendered ischemic for 24 and 72 hours after MCA occlusion contained 1101 +/- 48, and 1663 +/- 147, respectively. The 11-HETE content was significantly increased 72 hours after MCA occlusion (p less than 0.05). The MV fraction of rat brain contained 11-HETE (653 ng/mg protein) ten times as much as the other fraction. The identification of 11-HETE in the rat brain is a new finding.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1985

[Some practical problems and several methodological trials in continuous intracranial pressure monitoring].

The continuous intracranial pressure monitoring has been widely applied in intensive or critical care, but there are various kinds of methods for its monitoring at present. One hundred and forty-one cases mostly with severe head injury were subject to the intracranial pressure recordings in the critical care ward in Department of Emergency Medicine, University of Tokyo Hospital, from October, 1980 through May, 1983, and in Neurosurgical Unit, Showa General Hospital, in April and May, 1984. The authors made several methodological trials for the monitorings in them and compared with one another from the aspect of clinical practice. The subarachnoid catheter was inserted into the subarachnoid or sometimes into the subdural spaces by way of the burr hole in 112 cases and proved not to demonstrate in some cases the intracranial pressure waves clearly due to so called damping phenomenon but to indicate the reliable values, or trustworthy mean pressures in all the cases except for impending brain dead patients with swollen hemispheres and least cerebrospinal fluid remained in intracranial subarachnoid spaces. The ventricular fluid pressure was monitored in nine cases and was most dependable as well as the subarachnoid pressure. The ventricular cannulation and its maintenance were, however, difficult when the ventricles were compressed or deviated, which were often experienced in acute severe head injury and also in impending brain death just because of the same above mentioned reasons. These demerits were attempted to be conqured with epidural pressure monitorings such as the fiberoptic sensor (Ladd) in 17 cases, the intracranial catheter tip pressure transducer (Gaeltec) in nine cases and the sensor of bioimplantable polymer (Plastimed) in three cases.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1985

[A clinical study on the prognosis of infants born by breech delivery].

The influence of breech and vertex delivery on intrapartum fetal and neonatal mortality was studied in 8,863 infants delivered at Kurashiki Central Hospital Perinatal Center. The rate of mortality was studied in cases without fatal congenital anomalies. The frequency of congenital anomaly was also studied in 8,863 infants delivered by breech and vertex presentation. Infants were divided into five groups according to their birth weight: 99g or less, 1,000-1,499g, 1,500-1,999g, 2,000-2,499g and 2,500g or more. Infants were also grouped into four by gestational age: 24-27 weeks, 28-31 weeks, 32-36 weeks and 37 weeks or more. The total infant mortality rate was 4.9% in breech delivery, and 0.5% in vertex delivery, respectively. This difference was statistically significant. The rate of major congenital anomaly in breech delivery was significantly higher than in vertex delivery. The rate of premature deliveries in breech presentation was also significantly higher than in vertex delivery. The rate of mortality in the group weighing 1,000-1,499g was 50.0% in breech delivery, and 17.6% in vertex delivery, respectively. This difference was statistically significant. The rate of mortality in the group delivered at 28-31 weeks gestational age was 62.5% in breech delivery, and 15.4% in vertex delivery, respectively (statistically significant). The rate of severe neonatal asphyxia in infants delivered at 28-31 weeks of gestational age was significantly higher in breech delivery than in vertex delivery.

Birth Weight↗
PubMed1985

[Prognosis of metastatic brain tumor from lung cancer with special reference to its stages].

An overview of treatment of brain metastasis from lung cancer in National Cancer Center is presented with respect to T and N categories in TNM classification. To know the rate of brain metastasis, CT scan on brain was performed for all the patients with lung cancer hospitalized for surgical treatment and revealed that 3 of 87 patients had brain metastasis without any neurological signs and symptoms. On the other hand, 105 out of 320 (32.8%) lung cancer patients who had taken CT scan for some reason from 1975-1983 in this hospital had shown the brain metastasis. Therefore, it should be memorized that only 3.4% was detected to have brain metastasis from the patients without any neurological signs and symptoms. Two hundred sixty-one patients with metastatic brain tumor from lung cancer were treated in 1963-1983 at National Cancer Center in Japan. Of these, 205 patients were evaluated for the median survival and the average survival according to various therapeutic modalities. Of this 205 patients, 123 had no operation with or without other treatment--chemotherapy or radiotherapy showed median survival of 3-5 months (range 2-25 months). Eighty-two had operation on brain metastasis with or without chemotherapy showed median survival of 6-11 months (range 2-112 months). Correlation between survival time and T and N categories in TNM classification at the diagnosis of lung cancer was studied and no remarkable difference was noted either in T or N categories in the average survival time and percent number of cases survived equal or more than 6 months.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenocarcinoma↗
PubMed1984

Intensive chemotherapy with autologous bone marrow rescue for recurrent malignant gliomas.

Eight patients, four male and four female, were treated with high dose chemotherapy followed by bone marrow transplantation. In the first two patients, high dose ACNU was used for the treatment without combination with other drugs. This showed severe side effects such as intratumorous bleeding on the 18th day of treatment in the first case and pulmonary fibrosis on the 35th day of treatment in the second case. Considering these results, we considered another treatment schedule which consisted of high dose ADM (100 mg/m2), VCR (1.5 mg/m2), CDDP (80 mg/m2 X 4) and Ex (800 mg/m2) within seven days. Six patients were treated with this schedule and the results indicated that two patients had a partial response (more than 50% reduction of tumour size measured by CT scan), one had a complete remission (no tumour detected by CT scan), two showed no change and one, progression of the lesion. The patients recovered from the suppression of bone marrow function after the bone marrow transplantation as indicated. Granulocytes and platelets in blood began to increase from 10 to 14 days after the transplantation and became normal within three weeks after this. Serial measurements of S-GOT and alkaline phosphatase revealed reversible elevation, if any, within four weeks of the treatment. The number of our cases is still small, but results showed that autologous bone marrow transplantation made high dose chemotherapy possible. The necessity for consideration of the blood-brain barrier for this treatment is also discussed.

Adult↗
PubMed1984

Cellular immunity and complement levels in hosts with brain tumours.

As a major defence mechanism against cancer, host immunological surveillance is composed of a cellular immunity as well as humoral immunity including antibody and a complement system. In the course of the progress of brain tumours alone, serum complement level (CH 50) as a humoral immunological factor and the tuberculin skin reactivity as an index of cellular immune activity, were serially measured in brain tumour patients. One hundred and fifty-seven cases of brain tumours, including 75 cases of glioma, 25 benign tumours, and 42 metastatic tumours, were examined. Most cases of benign tumour belong to stage I oder II, in which both tuberculin reaction and complement are active. Many cases of glioblastoma and metastatic tumour belong to stage III; that is, they show negative tuberculin reaction and increased complement activity. The relation of immunological response to the tumour size and the clinical severity in patients with gliomas is revealed by the fact that complement titres rise in accordance with the degree of progress of the tumour and a negative tendency in the tuberculin reaction runs parallel to this. All cases of glioma, even in the terminal stages, remain in stage III. On the other hand, cases of metastatic tumour progress to stage IV and V, in which the tuberculin reaction is negative and complement titres decrease. The combined results of elevated complement level and depressed status of tuberculin reaction in patients with gliomas may be explained by the concept that complement activity rises to compensate for depressed cell-mediated immunity, in order to preserve the activity of the biophylaxis mechanism against cancer.

Adult↗
PubMed1984

Amelioration of ischaemic cerebral oedema by a free radical scavenger, AVS: 1,2-bis(nicotinamido)-propane. An experimental study using a regional ischaemia model in cats.

The effect of a free radical scavenger, AVS: 1,2-bis(nicotinamido)-propane, on the blood flow, oedema, and energy metabolites in the cortical area rendered ischaemic by the occlusion of the middle and the internal cerebral arteries was studied using cats. The development of cortical oedema was assessed by the changes in the specific gravity as well as the water and electrolyte contents of the cortical samples obtained 4 h after the arterial occlusion. Compared to the control group receiving saline, the AVS group exhibited a significant amelioration of cortical oedema, whereas no effect of AVS on the cortical blood flow was observed. The decrease of the energy charge and the increase of lactate in the ischaemic cortical area were less pronounced in the AVS groups. These data indicate that AVS possesses an action to mitigate the development of cortical oedema following regional ischaemia. The possible mechanism of action of AVS is discussed in reference to the free radical hypothesis.

Animals↗
PubMed1984

Nature of the vasoactive substance in CSF from patients with subarachnoid hemorrhage.

The purpose of this experiment was to study the nature of vasoactive substance in cerebrospinal fluid (CSF) from patients with aneurysmal subarachnoid hemorrhage. The authors have examined the effects of disulfide bond-reducing agents, a sulfhydryl group oxidizing agent, and specific antagonists of so-called "classical" neurotransmitters on the in vitro isometric contraction of canine basilar arterial strips induced by bloody human CSF. The disulfide bond-reducing agents dithiothreitol (10(-4) M) and dithioerythritol (10(-4) M) suppressed the contraction induced by bloody CSF by an average of 40.3% and 61.2%, respectively. This suppression was achieved under conditions that did not alter KCl-induced contraction. The sulfhydryl group oxidizing agent, 5,5'-dithiobis-(2-nitrobenzoic acid), 10(-4) M, reversed the inhibitory effect of dithioerythritol on the contractile response to bloody CSF. No significant suppression of any response in any preparation was observed with methysergide (10(-7) M), mepyramine (10(-7) M), phenoxybenzamine (10(-5) M), propranolol (10(-6) M), or atropine (10(-6) M). These results indicate that disulfide bonds in the arterial smooth-muscle cells are involved in the contractile responses of canine basilar artery to bloody CSF. Prostaglandins, hemoglobin, and lipid hydroperoxides may all be spasmogens in bloody CSF, while serotonin, histamine, norepinephrine, and acetylcholine are probably not involved.

Animals↗
PubMed1984

[The effect of high frequency jet ventilation on intracranial pressure in the patients with severe head injury].

The effect of high frequency jet ventilation (HFJV) on intracranial pressure (ICP) in the series of seven patients with severe head injury was studied. These patients received mechanical ventilation for respiratory failure accompanied with neural damage or circulatory shock and for ICP control by decreasing PaCO2. ICP was measured continuously by subarachnoid catheter method connected to Gould P-50 strain-gage transducer and controlled by hyperventilation and/or osmotic diuretics during acute phase. Arterial pressure, central venous pressure and intratracheal pressure were measured continuously in the same way. Arterial blood gases were analysed by BG-I of Technicon Co. Ltd. At the weaning from respirator, two methods were applied. One was conventional IMV (with PEEP) and/or CPAP by using IMV mode of Servo 900 respirator or T-piece together with PEEP valve and another was new-fashioned HFJV. Mean intratracheal pressure (mPit) was fixed at 0 mmHg (control value), 5, 10 and 15mmHg in both methods by adjusting PEEP valve or driving pressure of HFJV. The result is that in the same patients ICP was significantly lower during HFJV than IMV/CPAP when mPit was 5 and 10mmHg. Only three cases having been studied at 15mmHg of mPit because circulatory condition would not permit it, significant difference of ICP between HFJV and IMV/CPAP was not detected. PaCO2, being suspected to be the cause of lower ICP of HFJV group, was studied too. But blood gas analysis showed no significant difference neither PaCO2 nor PaO2. The fluctuation of CVP reflecting the change of intrathracic pressure was smaller in HFJV group than in IMV/CPAP group.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1984

[Brighton epistaxis balloon: application for cranio-facial injury].

Head injury patients often complicate facial and/or multiple injuries other than cranio-cerebral insults and perplex the emergency staffs. The authors used Brighton epistaxis balloon for such patients with massive nasal bleeding and reported the utility of the balloon not only in such state of emergency but also for a few days to control the hemorrhage mostly caused by craniobasal fractures or rupture of the adjacent vessels. One hundred and twenty-nine patients were transported and hospitalized in Department of Emergency Medicine, University of Tokyo Hospital, Tokyo, Japan during the period from October, 1981 to January, 1983. Nasal bleeding was noted in 29 cases of them and the balloon was used in 10 cases, who were from 19 to 76 years of age, all males and suffered from basal fractures or craniofacial injuries. Six cases of them were also accompanied with fractures in the extremities or pelvis, hemopneumothorax and/or intra-abdominal bleeding and could not but put on "Military anti-shock trousers" for the management of hypovolemic shock, hence the nasal bleeding should be managed immediately in the emergency room. In these situations the balloon was inserted into both nasal cavities in all the patients, to control successfully the nasal hemorrhages one of which contaminated cerebrospinal fluid and three of which were sure to be pulsatile due to arterial injury. The Brighton epistaxis balloon is to be removed within twelve or twenty-four hours, but in the authors' cases the mean duration for the hemostasis was 58.9 hours for 6 survivors and 49.6 hours for all 10 cases.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1984

[The effects of increased intracranial pressure on respiratory functions in clinical setting].

Respiratory insufficiency following acutely elevated intracranial pressure (ICP) may occur as a result of pulmonary edema which is supposed to be caused by increased sympathetic discharge from the central nervous system. Supporting experimental studies have been reported concerning this immediate respiratory consequence, while delayed respiratory consequences with an elevated ICP remain poorly characterized clinically. We studied delayed effects of an increased ICP on respiratory functions (pulmonary shunt ratio (Qs/Qt), respiratory index (A-aDO2/PaO2), oxygenation index (PaO2/FIO2) ), extravascular lung water (EVLW), and hemodynamics [cardiac index (CI), mean arterial pressure (MAP), mean pulmonary arterial pressure (MPAP), pulmonary capillary wedge pressure (PCWP), systemic vascular resistance (SVR), pulmonary vascular resistance (PVR)] in 15 cases with head injury, 4 with cerebrovascular diseases, and one with hypoxic brain damage. Ten cases had either aspiration, long bone fractures (the syndrome of fat embolism), or pneumonia, and the 10 cases without these pulmonary insults were defined as the cases without pulmonary complications and studied further. Pulmonary functions deteriorated as the ICP rose in the total cases, but in the cases without pulmonary complications, the correlations between the pulmonary functions and the ICP were not significant. None of the hemodynamic parameters correlated with the ICP in both the total cases and the cases without pulmonary complications.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1984

[Significance of hematoma irrigation with trephination therapy (HITT) in the management of acute subdural hematoma].

Decompressive craniectomy in the management of acute traumatic subdural hematoma (acute SDH) has been advocated as a treatment for the cerebral edema or swelling associated with it. The bony decompression with dural grafting seems successful in some patients, but surely enhances cerebral swelling and exacerbates edema in others. Whether the external or internal decompression could be justified is therefore a subject of controversy for the surgical treatment of choice. The authors, herein, proposed the new method with small craniectomy, 3 cm in diameter and irrigation with Nelaton's catheter for acute SDH with cerebral edema or swelling, that is the hematoma irrigation with trephination therapy (HITT) and performed it in 27 adult cases, 19 to 84 years of age (20 males and 7 females), who were transported within 24 hours after trauma and hospitalized in Department of Emergency Medicine, University of Tokyo Hospital during the period from January, 1982 to January, 1984, whose Glasgow coma scale points were 3 to 8 on admission, 16 cases (59%) of whom showed unilateral or bilateral absence of light reflex. The patients were all placed under the intensive care, using artificial ventilation (27 cases, 100%), hemodynamic management with Swan-Ganz catheter insertion (10 cases, 37%), continuous intracranial pressure monitoring (27 cases, 100%) and barbiturate therapy (13 cases, 48%). Ten cases (37%) recovered, 3 (11%) fell in vegetative state, 2 of whom died of medical complications afterwards and 14 (52%) could not avoid progressive deterioration to result in brain death.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1984

[Auditory evoked brain-stem responses (ABRs) in brain dead status].

Auditory evoked brain-stem responses (ABRs) were recorded in 19 out of 52 brain dead cases in Department of Emergency Medicine, University of Tokyo Hospital from May, 1981 to January, 1984. The causes of brain death were severe head injury (9 cases), cerebro-vascular disease (7 cases), anoxia (2 cases), hydrocephalus (1 case). Eleven cases of them fulfilled the clinical criteria which included absence of cortical and brain-stem functions excluding severe hypothermia and depressant drug intoxication. The remainders who were subjected to barbiturate therapy were diagnosed as brain death for non-filling phenomenon in cerebral angiography. Results were as follows; Fourteen cases (74%) had no identifiable ABR waves. One case (5%) had only 1st wave. Three cases (16%) had 1st and 2nd waves. One case (5%) had 1st, 2nd, and 3rd waves. In spite of definition of clinical brain death, 5 cases had at least 1st wave, and therefore these datum suggested that ABR might have less clinical utility in diagnosis of brain death. Each case did not necessarily demonstrate the total extinction of ABRs, as was shown in (2) to (4) mentioned above. The clinical status which met the criteria of brain death might therefore possibly imply any conditions in which brain death was impending gradually to result in the total brain death of cerebrum through medulla oblongata. Under these circumstances, how barbiturate might produce ABRs abnormality remained unsolved, though it has been said not to produce ABRs abnormality. Among 8 cases under barbiturate therapy, there were 5 cases with no identifiable waves and 3 cases with 1st and 2 nd waves.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗