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Biomedical subjects

K Takeuchi

Publications and source records attributed to K Takeuchi.

At least 1,261 records · Page 70Linked to original sources
PubMed1983

Effect of luminal pH and nutrient bicarbonate concentration on restitution after gastric surface cell injury.

Frog fundic mucosas whose surface layers were severely injured by exposure to 1 M NaCl for 10 minutes in an Ussing chamber uniformly recovered both physiologically and anatomically within 4 to 6 hours. The purpose of the present study was to examine the effects of luminal H+ and nutrient HCO-3 concentrations on this process of reconstitution. With 18 mM HCO-3, return of the transmucosal potential difference, tissue electrical resistance, and short-circuit current toward normal and anatomic recovery occurred at luminal pH of 7.4, 5.0, and 4.0 but not at 3.0. An inhibitor of pepsin did not favorably affect the outcome of luminal pH 3.0, but a nutrient HCO-3 concentration of 47.8 mM completely prevented the adverse effects of luminal pH 3.0. Reconstitution of epithelial integrity did not occur in the absence of HCO-3 at luminal pH 4.0. Thus, low luminal pH inhibits and high nutrient HCO-3 concentration supports the epithelial restitution after mucosal damage caused by hyperosmolar NaCl.

Animals↗
PubMed1983

[Immunological monitoring of brain tumors--prognosis and cellular immunity of patients with brain tumors].

The usefulness of in vivo skin tests for reaction to purified protein derivative (PPD) and phytohemagglutinin (PHA) for assessment of cell mediated immunity was investigated among 31 patients with brain tumors. These included 22 gliomas and 9 metastatic brain tumors. Each patient was administered intradermal injections of 0.05 micrograms PPD and 0.5 micrograms PHA, and erythema was observed in each case. A positive reaction (erythema diameter greater than 10 mm) to PPD was observed in 8 (74%) of 11 low grade gliomas, 3 (27%) of 11 malignant gliomas and 6 (67%) of 9 metastatic brain tumors. A positive reaction (erythema diameter greater than 25 mm) to PHA was observed in 8 (74%) of 11 low grade gliomas, 4 (36%) of 11 malignant gliomas, and 6 (67%) of 9 metastatic brain tumors. In repeated PHA skin reaction tests conducted at intervals of one month, the reaction of the patients depended on their clinical state. Thirteen of the patients died. The PHA skin reaction of 7 of the 13 patients who survived for more than 6 months was all negative 6 months prior to death, and continued and repeated reaction tests did not result in a positive finding except for one patient with malignant glioma. In 10 of the 13, the PHA skin reaction was negative one month prior to death, and the final test result was negative for 11 of the 13.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1983

[Evaluation of brain death by computed tomography].

The absence of cerebral circulation and electrocerebral silence have served as an accurate index of irreversible brain death. It is proposed that computed tomography (CT) findings be evaluated as confirmatory criteria of brain death. To this end, CT evaluation of 14 patients satisfying the conventional criteria of brain death was performed. A.CT finding of severe compression or disappearance of the ventricular system, or so-called "brain tamponade", was seen in 7 (50%) of the 14 patients. Enhanced contrast CT, especially dynamic CT, usually distinctly reveals the cerebral vessels whenever the cerebral blood flow is preserved; conversely, the lack of enhanced brain structures, even comparing attenuation values, indicates the absence of cerebral blood flow. In 7 (70%) of 10 patients, however, there was enhanced contrast of vascular brain structures, especially the circle of Willis, major cerebral arteries, choroid plexuses, and venous sinuses. It is suggested that this result is due to the improvement of demonstrability by CT. The usefulness of CT in the confirmation of brain death lies in visualization of the pathological changes associated with a dead brain, such as "brain tamponade", and the lack of enhanced contrast indicating the absence of cerebral blood flow. The latter point is still problematic as angiography revealed an extremely low cerebral blood flow in a few cases of "dead brain" patients. It is recommended that cerebral blood flow in brain death be evaluated by dynamic CT scanning and correlated with other methods of cerebral blood flow determination (e.g., intravenous digital subtraction angiography).

Adult↗
PubMed1983

[Significance of the fourth heart sound in patients with angina pectoris].

To determine the physiological significance of the fourth heart sound at rest in patients with angina pectoris without previous myocardial infarction, the tension time index (TTI) and the ratio of the diastolic pressure time index (DPTI) to (DPTI/TTI) were calculated from the recordings of the left ventricular and aortic pressure curves. Thirty patients were subjected to the study and they were classified into two groups: Group A consisted of 15 patients with the fourth heart sound and Group B of 15 patients without it. Nine cases of atypical chest pain without the fourth heart sound served as control group. TTI was significantly higher in Group A than in Group B (p less than 0.01) and control group (p less than 0.01) (2,552 +/- 489 mmHg X sec/min in Group A, 2,024 +/- 425 mmHg X sec/min in Group B, and 2,023 +/- 209 mmHg X sec/min in control group). DPTI/TTI was significantly lower in Group A than in Group B (p less than 0.01) and control group p less than 0.001) (1.16 +/- 0.19 in Group A, 1.55 +/- 0.39 in Group B, and 1.45 +/- 0.15 in control group). Left ventricular systolic pressure tended to be higher in Group A than in Group B and control group. There was no significant difference in left ventricular end-diastolic pressure, left ventricular ejection fraction and cardiac index among three groups and there was no difference in the prevalence of left ventricular asynergy on left ventriculography between Group A and Group B.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1983

[Intracranial pressure changes during sleep in man].

ICP being a very significant parameter of intracranial pathology, it needs to be recorded continuously. ICP of 7 cases of normal pressure hydrocephalus (NPH) and 6 postoperative patients, for whom relationship between REM sleep and ICP was under discussion, was monitored at night and recorded by Brock's method. Polygraphic records also were obtained. Increased ICP was related to REM sleep in 3 of 6 postoperative cases. In the remaining 3 cases, REM sleep could not be observed the first postoperative night, and ICP was lower and stable all night. This fact may be an effect of anesthetic drugs. NPH patients were divided into 2 groups by pressure profile during night recording of ICP. One group of 2 cases demonstrated irregular ICP during REM sleep while the other group of 5 cases did not. The former 2 cases showed neurological improvement after shunt operations. In NPH cases, ICP has significance in deciding whether surgery is necessary. It appears reasonable to suggest that the augumentation of ICP during REM sleep in cases of hydrocephalus and postoperative condition is related to an increase in cerebral blood flow and an exhaustion of the absorptive mechanisms of CSF.

Adult↗
PubMed1983

[CSF dynamics following shunt operation, with special reference to the diurnal changes of CSF circulation].

The purpose of this study is to study the pathophysiology of the cerebrospinal fluid (CSF) formation and circulation after a ventriculoperitoneal shunt operation. With the CSF flowmeter we developed, the CSF flow rate in the shunt tube has been measured non-traumatically over a 24-hour period in six patients. These include both communicating and noncommunicating hydrocephalus patients with ages ranging from 20 to 70. There were three cases of ruptured intracranial aneurysm, one cerebral contusion, one hypertensive brain stem hemorrhage and one occlusion of the aqueduct sylvius. Intraventricular pressure was continuously recorded for 24 hours prior to the shunt operation in each case, and the pressure changes were compared with the measured CSF flow rates in the shunt tube. The flow rate fluctuated between 0.05 ml/min and 1.2 ml/min with the supine position and high flow rates were detected in the early morning. Each case showed its own rhythm of CSF flow fluctuation during a 24-hour period, and the changes were compatible with the intraventricular pressure. It is suggested that there may be a relationship between these changes and an increased cerebral blood volume during the REM sleep stage.

Adult↗