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T Aiba

Publications and source records attributed to T Aiba.

At least 91 records · Page 5Linked to original sources
PubMed1987

[Trigeminal somatosensory evoked potentials: I. Recording technic and normal responses].

The general wave form and time course of somatosensory evoked potentials (SEP) to the stimulation of upper and lower extremities has been well known in recent years. However, only a little information has been published so far on SEP to the trigeminal nerve stimulation (TSEP), and at present there is not always common methodology available in clinical practice. These may be due to the technical problems from the close proximity of stimulating and recording electrodes. The purpose of this report is to attempt to solve some of the difficulties of the procedure, as well as to show the morphology and time course of TSEP in a group of normal healthy subjects. Twenty healthy volunteers were investigated. Their age ranged from 22 to 61 years old (mean 29.3). Clip shaped silver-balled stimulating electrodes with 2 mm contact surface and interelectrode distance of 10 mm were applied to the inner surface of the lips. They were held in place without any support, thus minimizing muscle activity of the subject. Each half of the upper and lower lip was then stimulated in turn by an electrical rectangular pulse of 3 or 4 times sensory threshold (usually 1.5-2.0 mA) and 0.2 msec duration, at a rate of 2.3 per second. TSEP was recorded contralaterally from C'5 or C'6 (midpoint between Cz and external auditory porus). Fz was used as a reference. Four hundred responses were averaged by a Nicolet Pathfinder II, which also generated stimulation pulses. Stimulus polarity was reversed after each 100 stimuli to eliminate stimulus artifact. Analysis time was set to 50 msec.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1986

Development of synthetic lung surfactants.

We have previously reported the development of a reconstituted lung surfactant consisting of an organic solvent extract of natural bovine lung surfactant supplemented with synthetic lipids. This "artificial" surfactant was used successfully to treat surfactant deficiency states both in animals and humans. We now report on the successful testing of a synthetic lung surfactant consisting of a lipid-bound protein isolated from natural lung surfactant and the lipids present in the "artificial" lung surfactant and now used in the same concentration but in a synthetic, commercially available form. The synthetic lung surfactant possessed the in vitro and in vivo surface properties characterizing the "artificial" lung surfactant. In order to identify the components of the synthetic lung surfactant that are responsible for the required surface properties, a series of 25 simple mixtures was prepared. Of these, three possessed surface properties very similar to those of the "artificial" lung surfactant and the synthetic lung surfactant, in vitro as well as in vivo. These three mixtures had four components in common. Besides dipalmitoyl phosphatidylcholine and the lipid-bound protein, they each had a saturated fatty acid, palmitic or stearic, and they each had an acidic phospholipid, phosphatidylglycerol or phosphatidylserine.

Animals↗
PubMed1985

Decrease in human growth hormone (HGH) levels during transsphenoidal surgery for acromegaly as a guide for prognosis.

To evaluate the clinical significance of human growth hormone (HGH) dynamics during transsphenoidal microsurgery for acromegaly, serial HGH levels during the surgery were compared with the post-operative basal HGH levels in 15 acromegalic patients, retrospectively. In all patients, in whom the HGH level immediately after tumor resection was reduced below 5 ng/ml or the decreasing rate which stood for the magnitude of decrease of HGH during resection procedure was above 80%, postoperative permanent HGH levels fell to below 5 ng/ml, namely, within the normal range. The rapid radioimmunoassay (RIA) of HGH was developed by the use of high affinity antibody in order to inform the surgeons of plasma HGH levels quickly during the surgery. It is now possible to know HGH levels about 1 hour after submitting the samples. It was verified that HGH levels measured in the rapid RIA correlated well with those obtained in the conventional way. The rapid RIA method was applied to 6 patients and the correlation between HGH levels during the surgery and post operative levels was also studied prospectively. The results were essentially identical to those in a retrospective study. It was suggested that the HGH level immediately after tumor resection and the extent of the decrease in HGH during the resection procedure were good indicators of the prognosis of surgical results in acromegaly and the rapid RIA method was useful in order to judge HGH levels quickly during the surgery.

Acromegaly↗
PubMed1985

[Anti-platelet therapy in ischemic cerebrovascular disorder--clinical and hematological study].

Anti-platelet therapy (Aspirin 250 mg/every other day approximately 1000 mg/day + Dipyridamole 150 mg/day) was performed on 51 patients with ischemic cerebrovascular disorders (ICVD). Among these patients, 41 cases showed no recurrence of ICVD attack, whereas the remaining 10 cases had re-attacks. These 2 groups were compared from the viewpoint of various risk factors and other clinical findings: e.g. CT scan and angiographic appearance. But there was no statistically significant difference between them. Platelet aggregability and platelet survival time were examined in twenty-eight patients out of cases. We used a simple nonradioisotope technic for the determination of platelet survival time. Platelet survival time was shortened in 22 of 28 (79%) patients. On the other hand, platelet aggregability was found to have no definite tendency. In 9 of 10 cases, platelet survival time was revealed to be prolonged several months after administration of anti-platelet drugs. There was no re-attack in 7 of these 9 patients. Some reports also showed that platelet survival time was shortened in various thromboembolism and recovered by anti-platelet drugs. Measurement of platelet survival time is thought to be an important method as to the indication and the monitoring of anti-platelet therapy.

Adult↗
PubMed1984

[The heterogeneity of serum hPRL in a patient with a giant prolactinoma].

The heterogeneity of hPRL in the serum of a patient with a giant prolactinoma (hPRL 27 micrograms/ml) was studied employing gel chromatography, RIA and lymphoma cell bioassay. After gel filtration of serum sample on Sephadex G-100 (superfine) column, a few hPRL peaks were detected by RIA. Rechromatography of the second peak, which eluted between the void volume and the small third peak, revealed four hPRL peaks designated big-big hPRL, medium-big hPRL, big hPRL and little hPRL, with BA/RIA ratio 1.3 approximately 2.6, 0.8 approximately 1.2, 0.3 approximately 0.7 and 0.7 approximately 1.5, respectively. The molecular weight of medium-big hPRL was estimated as 80K approximately 90K daltons. Most of big-big, medium-big and big hPRL were converted to little hPRL after mercaptoethanol treatment. These data suggest that most of big-big, medium-big and big hPRL are aggregates of little hPRL.

Adult↗
PubMed1984

Discrepancy between immunoactivity and bioactivity of big-big and big human growth hormones in acromegaly.

The heterogeneity of hGH in the sera, culture media of tumor cells and tumor extract from acromegalic patients was studied employing gel chromatography, RIA and lymphoma cell bioassay. The chromatographic profile of the sera on Sephadex G-100 (superfine) column showed three peaks: the major peak eluted with 125I-hGH (little hGH), the less retarded small peak (big hGH) and the peak at void volume (big-big hGH). Bioassay to radioimmunoassay ratio of big-big, big and little hGH were 1.07-5.75, 0.25-0.70 and 0.70-1.56, respectively. These ratios were not significantly different among the acromegalic sera obtained before and after TRH test. The longer duration sera were kept for, the higher percent of big-big hGH and the lower percent of little hGH the sera contained by RIA. The percentage of big-big hGH was less in the culture media of tumor cells than that in acromegalic sera, and the least in tumor extract by RIA. Rechromatography of big-big hGH fraction of tumor extract showed the conversion of big-big hGH to big and little hGHs. These data suggest that big-big hGH was artificially made from little and big hGH during storage. Rechromatography of fractions between big-big hGH and big hGH produced another peak (medium-big hGH) with approximately 80 K-90 K daltons of molecular weight. This peak was converted to almost a little hGH peak after mercaptoethanol treatment and was supposed to be a tetramer of little hGH.

Acromegaly↗
PubMed1984

[Primary intracranial hypotension associated with chronic subdural hematoma--report of 2 cases].

Low spinal fluid pressure syndrome is characterized by orthostatic headache aggravated in upright position. It is classified into two from etiological standpoint i.e. primary and secondary (most often seen after lumbar puncture). On the other hand, low spinal fluid pressure is one of the promoting factors of chronic subdural hematoma. We report 2 cases of primary low spinal fluid pressure syndrome (primary intracranial hypotension) associated with chronic subdural hematoma. Case 1 is a 47-year-old man who was admitted with disorientation following 2 week history of orthostatic headache. Spinal fluid pressure was 7mmH2O in the lateral recumbent position. CT scan revealed bilateral isodense chronic subdural hematoma. The subdural hematoma reaccumulated 17 days after the first operation. Case 2 is a 31-year-old woman who was admitted with 4 week history of progressive orthostatic headache accompanied by nausea and vomiting. Spinal fluid pressure was 0 mmH2O. CT scan and cerebral angiography showed bilateral chronic subdural hematoma. The hematoma reaccumulated 20 days after the first operation. Six cases including our two cases of primary intracranial hypotention associated with chronic subdural hematoma have been reported. When changes of characters of headache, especially mental symptoms and disturbances of consciousness occurred in patients with chronic orthostatic headache, association of chronic subdural hematoma should be suspected. In cases with chronic subdural hematoma associated with low spinal fluid pressure syndrome, the reaccumulation of hematoma tends to occur after burr hole opening and irrigation of hematoma.

Adult↗